From c02414a99796487a2124e4dbb17c3a88c8606404 Mon Sep 17 00:00:00 2001
From: Brian Lyles <brianmlyles@gmail.com>
Date: Fri, 6 Sep 2024 09:50:08 -0500
Subject: [PATCH 001/259] interpret-trailers: handle message without trailing
 newline

When git-interpret-trailers is used to add a trailer to a message that
does not end in a trailing newline, the new trailer is added on the line
immediately following the message instead of as a trailer block
separated from the message by a blank line.

For example, if a message's text was exactly "The subject" with no
trailing newline present, `git interpret-trailers --trailer
my-trailer=true` will result in the following malformed commit message:

    The subject
    my-trailer: true

While it is generally expected that a commit message should end with a
newline character, git-interpret-trailers should not be returning an
invalid message in this case.

Use `strbuf_complete_line` to ensure that the message ends with a
newline character when reading the input.

Signed-off-by: Brian Lyles <brianmlyles@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 builtin/interpret-trailers.c  |  1 +
 t/t7513-interpret-trailers.sh | 40 +++++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/builtin/interpret-trailers.c b/builtin/interpret-trailers.c
index 1d969494cf5471..e6f22459f15334 100644
--- a/builtin/interpret-trailers.c
+++ b/builtin/interpret-trailers.c
@@ -132,6 +132,7 @@ static void read_input_file(struct strbuf *sb, const char *file)
 		if (strbuf_read(sb, fileno(stdin), 0) < 0)
 			die_errno(_("could not read from stdin"));
 	}
+	strbuf_complete_line(sb);
 }
 
 static void interpret_trailers(const struct process_trailer_options *opts,
diff --git a/t/t7513-interpret-trailers.sh b/t/t7513-interpret-trailers.sh
index 3d3e13ccf87215..0f7d8938d984d9 100755
--- a/t/t7513-interpret-trailers.sh
+++ b/t/t7513-interpret-trailers.sh
@@ -175,6 +175,46 @@ test_expect_success 'with only a title in the message' '
 	test_cmp expected actual
 '
 
+test_expect_success 'with a bodiless message that lacks a trailing newline after the subject' '
+	cat >expected <<-\EOF &&
+		area: change
+
+		Reviewed-by: Peff
+		Acked-by: Johan
+	EOF
+	printf "area: change" |
+	git interpret-trailers --trailer "Reviewed-by: Peff" \
+		--trailer "Acked-by: Johan" >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'with a bodied message that lacks a trailing newline after the body' '
+	cat >expected <<-\EOF &&
+		area: change
+
+		details about the change.
+
+		Reviewed-by: Peff
+		Acked-by: Johan
+	EOF
+	printf "area: change\n\ndetails about the change." |
+	git interpret-trailers --trailer "Reviewed-by: Peff" \
+		--trailer "Acked-by: Johan" >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'with a message that lacks a trailing newline after the trailers' '
+	cat >expected <<-\EOF &&
+		area: change
+
+		Reviewed-by: Peff
+		Acked-by: Johan
+	EOF
+	printf "area: change\n\nReviewed-by: Peff" |
+	git interpret-trailers --trailer "Acked-by: Johan" >actual &&
+	test_cmp expected actual
+'
+
 test_expect_success 'with multiline title in the message' '
 	cat >expected <<-\EOF &&
 		place of

From 87cf96094a6b5ccc4a9a1d92b9958ad0869a5c90 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20Scharfe?= <l.s.r@web.de>
Date: Sun, 8 Sep 2024 09:05:44 +0200
Subject: [PATCH 002/259] diff: report copies and renames as changes in
 run_diff_cmd()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The diff machinery has two ways to detect changes to set the exit code:
Just comparing hashes and comparing blob contents.  The latter is needed
if certain changes have to be ignored, e.g. with --ignore-space-change
or --ignore-matching-lines.  It's enabled by the diff_options flag
diff_from_contents.

The slower mode has never considered copies and renames to be changes,
which is inconsistent with the quicker one.  Fix it.  Even if we ignore
the file contents (because it's empty or contains only ignored lines),
there's still the meta data change of adding or changing a filename, so
we need to report it in the exit code.

d7b97b7185 (diff: let external diffs report that changes are
uninteresting, 2024-06-09) set diff_from_contents if external diff
programs are allowed.  This is the default e.g. for git diff, and so
that change exposed the inconsistency much more widely.

Reported-by: Jorge Luis Martinez Gomez <jol@jol.dev>
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 diff.c                 |  3 +++
 t/t4017-diff-retval.sh | 16 ++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/diff.c b/diff.c
index ebb7538e040a71..53e41a8d6c66ad 100644
--- a/diff.c
+++ b/diff.c
@@ -4587,6 +4587,9 @@ static void run_diff_cmd(const struct external_diff *pgm,
 		builtin_diff(name, other ? other : name,
 			     one, two, xfrm_msg, must_show_header,
 			     o, complete_rewrite);
+		if (p->status == DIFF_STATUS_COPIED ||
+		    p->status == DIFF_STATUS_RENAMED)
+			o->found_changes = 1;
 	} else {
 		fprintf(o->file, "* Unmerged path %s\n", name);
 		o->found_changes = 1;
diff --git a/t/t4017-diff-retval.sh b/t/t4017-diff-retval.sh
index f439f469bd2bfd..9a4f5786140cfc 100755
--- a/t/t4017-diff-retval.sh
+++ b/t/t4017-diff-retval.sh
@@ -143,4 +143,20 @@ test_expect_success 'option errors are not confused by --exit-code' '
 	grep '^usage:' err
 '
 
+for option in --exit-code --quiet
+do
+	test_expect_success "git diff $option returns 1 for copied file" "
+		git reset --hard &&
+		cp a copy &&
+		git add copy &&
+		test_expect_code 1 git diff $option --cached --find-copies-harder
+	"
+
+	test_expect_success "git diff $option returns 1 for renamed file" "
+		git reset --hard &&
+		git mv a renamed &&
+		test_expect_code 1 git diff $option --cached
+	"
+done
+
 test_done

From 11591850ddd5e65d3d0aab22c0a7131b1eb1d6f0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20Scharfe?= <l.s.r@web.de>
Date: Sun, 8 Sep 2024 09:08:35 +0200
Subject: [PATCH 003/259] diff: report dirty submodules as changes in
 builtin_diff()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The diff machinery has two ways to detect changes to set the exit code:
Just comparing hashes and comparing blob contents.  The latter is needed
if certain changes have to be ignored, e.g. with --ignore-space-change
or --ignore-matching-lines.  It's enabled by the diff_options flag
diff_from_contents.

The slower mode as never considered submodules (and subrepos) as changes
with --submodule=diff or --submodule=log, which is inconsistent with
--submodule=short (the default).  Fix it.

d7b97b7185 (diff: let external diffs report that changes are
uninteresting, 2024-06-09) set diff_from_contents if external diff
programs are allowed.  This is the default e.g. for git diff, and so
that change exposed the inconsistency much more widely.

Reported-by: David Hull <david.hull@friendbuy.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 diff.c                 |  2 ++
 t/t4017-diff-retval.sh | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/diff.c b/diff.c
index 53e41a8d6c66ad..a83409944b0243 100644
--- a/diff.c
+++ b/diff.c
@@ -3565,6 +3565,7 @@ static void builtin_diff(const char *name_a,
 		show_submodule_diff_summary(o, one->path ? one->path : two->path,
 				&one->oid, &two->oid,
 				two->dirty_submodule);
+		o->found_changes = 1;
 		return;
 	} else if (o->submodule_format == DIFF_SUBMODULE_INLINE_DIFF &&
 		   (!one->mode || S_ISGITLINK(one->mode)) &&
@@ -3573,6 +3574,7 @@ static void builtin_diff(const char *name_a,
 		show_submodule_inline_diff(o, one->path ? one->path : two->path,
 				&one->oid, &two->oid,
 				two->dirty_submodule);
+		o->found_changes = 1;
 		return;
 	}
 
diff --git a/t/t4017-diff-retval.sh b/t/t4017-diff-retval.sh
index 9a4f5786140cfc..d644310e22a5d1 100755
--- a/t/t4017-diff-retval.sh
+++ b/t/t4017-diff-retval.sh
@@ -159,4 +159,25 @@ do
 	"
 done
 
+test_expect_success 'setup dirty subrepo' '
+	git reset --hard &&
+	test_create_repo subrepo &&
+	test_commit -C subrepo subrepo-file &&
+	test_tick &&
+	git add subrepo &&
+	git commit -m subrepo &&
+	test_commit -C subrepo another-subrepo-file
+'
+
+for option in --exit-code --quiet
+do
+	for submodule_format in diff log short
+	do
+		opts="$option --submodule=$submodule_format" &&
+		test_expect_success "git diff $opts returns 1 for dirty subrepo" "
+			test_expect_code 1 git diff $opts
+		"
+	done
+done
+
 test_done

From 39ba986b0ea772ba41710c2a545fd07026b1f677 Mon Sep 17 00:00:00 2001
From: Ramsay Jones <ramsay@ramsayjones.plus.com>
Date: Mon, 9 Sep 2024 02:23:48 +0100
Subject: [PATCH 004/259] config.mak.uname: add HAVE_DEV_TTY to cygwin config
 section

If neither HAVE_DEV_TTY nor GIT_WINDOWS_NATIVE is set, while compiling
the 'compat/terminal.c' code, then the fallback code calls the system
getpass() function. Unfortunately, this ignores the 'echo' parameter of
the git_terminal_prompt() function, since it has no way to implement that
functionality. This results in a less than optimal user experience on
cygwin, which does not define either of those build flags.

However, cygwin does have a functional '/dev/tty', so that it can build
with HAVE_DEV_TTY and benefit from the improved user experience.

The improved git_terminal_prompt() function that comes with HAVE_DEV_TTY
is used in the git_prompt() function, which in turn is used by the
'git credential', 'git bisect' and 'git help' commands. In addition to
git_terminal_prompt(), read_key_without_echo() is likewise improved and
used by the 'git add -p' command.

While using the 'git credential fill' command, for example:

  $ printf "%s\n" protocol=https host=example.com path=git | ./git credential fill
  Username for 'https://example.com': user
  Password for 'https://user@example.com':
  protocol=https
  host=example.com
  username=user
  password=pass
  $

The 'user' name is now echoed while typing (the password isn't), where this
wasn't the case before.

When using the auto-correct feature:

  $ ./git -c help.autocorrect=prompt fred
  WARNING: You called a Git command named 'fred', which does not exist.
  Run 'grep' instead [y/N]? n
  $ ./git -c help.autocorrect=prompt fred
  WARNING: You called a Git command named 'fred', which does not exist.
  Run 'grep' instead [y/N]? y
  fatal: no pattern given
  $

The user can actually see what they are typing at the prompt. Similar
comments apply to 'git bisect':

  $ ./git bisect bad master~1
  You need to start by "git bisect start"

  Do you want me to do it for you [Y/n]? y
  status: waiting for both good and bad commits
  status: waiting for good commit(s), bad commit known
  $ ./git bisect reset
  Already on 'master-tmp'
  $

  $ ./git bisect start
  status: waiting for both good and bad commits
  $ ./git bisect bad master~1
  status: waiting for good commit(s), bad commit known
  $ ./git bisect next
  warning: bisecting only with a bad commit
  Are you sure [Y/n]? n
  $ ./git bisect reset
  Already on 'master-tmp'
  $

The read_key_without_echo() function leads to a much improved 'git add -p'
command, when the 'interactive.singleKey' configuration is set:

  $ cd ..
  $ mkdir test-git
  $ cd test-git
  $ git init -q
  $ echo foo >file
  $ git add file
  $ echo bar >file
  $ ../git/git -c interactive.singleKey=true add -p
  diff --git a/file b/file
  index 257cc56..5716ca5 100644
  --- a/file
  +++ b/file
  @@ -1 +1 @@
  -foo
  +bar
  (1/1) Stage this hunk [y,n,q,a,d,e,p,?]? y

  $

Note that, not only is the user input echoed, but that it is immediately
accepted (without having to type <return>) and the program exits with the
hunk staged (in this case) or not.

In order to reap these benefits, set the HAVE_DEV_TTY build flag in the
cygwin configuration section of config.mak.uname.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 config.mak.uname | 1 +
 1 file changed, 1 insertion(+)

diff --git a/config.mak.uname b/config.mak.uname
index 64c44db8058e0c..96e2ea8ec1c6ab 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -235,6 +235,7 @@ ifeq ($(uname_O),Cygwin)
 	else
 		NO_REGEX = UnfortunatelyYes
 	endif
+	HAVE_DEV_TTY = YesPlease
 	HAVE_ALLOCA_H = YesPlease
 	NEEDS_LIBICONV = YesPlease
 	NO_FAST_WORKING_DIRECTORY = UnfortunatelyYes

From 9a36ea37aea99750dbe05c6ef36a9e02722f5a07 Mon Sep 17 00:00:00 2001
From: Junio C Hamano <gitster@pobox.com>
Date: Mon, 9 Sep 2024 08:53:11 -0700
Subject: [PATCH 005/259] doc: remote.*.skip{DefaultUpdate,FetchAll} stops
 prefetch

Back when 7cc91a2f (Add the configuration option skipFetchAll,
2009-11-09) added for the sole purpose of adding skipFetchAll as a
synonym to skipDefaultUpdate, there was no explanation about the
reason why it was needed., but these two configuration variables
mean exactly the same thing.

Also, when we taught the "prefetch" task to "git maintenance" later,
we did make it pay attention to the setting, but we forgot to
document it.

Document these variables as synonyms that collectively implements
the last-one-wins semantics, and also clarify that the prefetch task
is also controlled by this variable.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 Documentation/config/remote.txt   | 13 +++++++------
 Documentation/fetch-options.txt   |  5 +++--
 Documentation/git-maintenance.txt |  3 +++
 3 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/Documentation/config/remote.txt b/Documentation/config/remote.txt
index 8efc53e836d20b..36e771556c67aa 100644
--- a/Documentation/config/remote.txt
+++ b/Documentation/config/remote.txt
@@ -42,14 +42,15 @@ remote.<name>.mirror::
 	as if the `--mirror` option was given on the command line.
 
 remote.<name>.skipDefaultUpdate::
-	If true, this remote will be skipped by default when updating
-	using linkgit:git-fetch[1] or the `update` subcommand of
-	linkgit:git-remote[1].
+	A deprecated synonym to `remote.<name>.skipFetchAll` (if
+	both are set in the configuration files with different
+	values, the value of the last occurrence will be used).
 
 remote.<name>.skipFetchAll::
-	If true, this remote will be skipped by default when updating
-	using linkgit:git-fetch[1] or the `update` subcommand of
-	linkgit:git-remote[1].
+	If true, this remote will be skipped when updating
+	using linkgit:git-fetch[1], the `update` subcommand of
+	linkgit:git-remote[1], and ignored by the prefetch task
+	of `git maitenance`.
 
 remote.<name>.receivepack::
 	The default program to execute on the remote side when pushing.  See
diff --git a/Documentation/fetch-options.txt b/Documentation/fetch-options.txt
index e22b217fba9e2c..80838fe37ef30e 100644
--- a/Documentation/fetch-options.txt
+++ b/Documentation/fetch-options.txt
@@ -1,6 +1,7 @@
 --[no-]all::
-	Fetch all remotes. This overrides the configuration variable
-	`fetch.all`.
+	Fetch all remotes, except for the ones that has the
+	`remote.<name>.skipFetchAll` configuration variable set.
+	This overrides the configuration variable fetch.all`.
 
 -a::
 --append::
diff --git a/Documentation/git-maintenance.txt b/Documentation/git-maintenance.txt
index 51d0f7e94b6a01..9d968191331080 100644
--- a/Documentation/git-maintenance.txt
+++ b/Documentation/git-maintenance.txt
@@ -107,6 +107,9 @@ with the prefetch task, the objects necessary to complete a later real fetch
 would already be obtained, making the real fetch faster.  In the ideal case,
 it will just become an update to a bunch of remote-tracking branches without
 any object transfer.
++
+The `remote.<name>.skipFetchAll` configuration can be used to
+exclude a particular remote from getting prefetched.
 
 gc::
 	Clean up unnecessary files and optimize the local repository. "GC"

From 90f2c7240ccc7fb349199b4ded6b47702b40331f Mon Sep 17 00:00:00 2001
From: Junio C Hamano <gitster@pobox.com>
Date: Mon, 9 Sep 2024 16:00:20 -0700
Subject: [PATCH 006/259] ci: remove 'Upload failed tests' directories' step
 from linux32 jobs

Linux32 jobs seem to be getting:

    Error: This request has been automatically failed because it uses a
    deprecated version of `actions/upload-artifact: v1`. Learn more:
    https://github.blog/changelog/2024-02-13-deprecation-notice-v1-and-v2-of-the-artifact-actions/

before doing anything useful.  For now, disable the step.

Ever since actions/upload-artifact@v1 got disabled, mentioning the
offending version of it seems to stop anything from happening.  At
least this should run the same build and test.

See

    https://github.com/git/git/actions/runs/10780030750/job/29894867249

for example.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 .github/workflows/main.yml | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 1ee0433acc14a2..97f9b063109411 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -365,12 +365,6 @@ jobs:
       with:
         name: failed-tests-${{matrix.vector.jobname}}
         path: ${{env.FAILED_TEST_ARTIFACTS}}
-    - name: Upload failed tests' directories
-      if: failure() && env.FAILED_TEST_ARTIFACTS != '' && matrix.vector.jobname == 'linux32'
-      uses: actions/upload-artifact@v1 # cannot be upgraded because Node.js Actions aren't supported in this container
-      with:
-        name: failed-tests-${{matrix.vector.jobname}}
-        path: ${{env.FAILED_TEST_ARTIFACTS}}
   static-analysis:
     needs: ci-config
     if: needs.ci-config.outputs.enabled == 'yes'

From dc542fcd6bb0fb6a85ac52f62c3e2f0849001cc8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20=C3=85gren?= <martin.agren@gmail.com>
Date: Wed, 11 Sep 2024 12:30:59 +0200
Subject: [PATCH 007/259] t1517: add missing LIBCURL prereq
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

After building Git with NO_LIBCURL, there is no `git remote-http`, so
it's not meaningful to test that it can run outside of a repository.
Indeed, that test will fail. Add the LIBCURL prereq to it.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 t/t1517-outside-repo.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/t/t1517-outside-repo.sh b/t/t1517-outside-repo.sh
index 990a03658214a4..342defbb617628 100755
--- a/t/t1517-outside-repo.sh
+++ b/t/t1517-outside-repo.sh
@@ -98,7 +98,7 @@ test_expect_success 'stripspace outside repository' '
 	nongit git stripspace -s </dev/null
 '
 
-test_expect_success 'remote-http outside repository' '
+test_expect_success LIBCURL 'remote-http outside repository' '
 	test_must_fail git remote-http 2>actual &&
 	test_grep "^error: remote-curl" actual &&
 	(

From 86b93bddeb53390746d5b5bd2ad1f47a89bc910e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20=C3=85gren?= <martin.agren@gmail.com>
Date: Wed, 11 Sep 2024 12:31:00 +0200
Subject: [PATCH 008/259] t0211: add missing LIBCURL prereq
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

After building Git with NO_LIBCURL, we're lacking `git remote-http` and
`git http-fetch`, so when we test that they trace as they should, we're
bound to fail. Add the LIBCURL prereq to those tests.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 t/t0211-trace2-perf.sh | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/t/t0211-trace2-perf.sh b/t/t0211-trace2-perf.sh
index 070fe7a5da7c24..dddc130560ba61 100755
--- a/t/t0211-trace2-perf.sh
+++ b/t/t0211-trace2-perf.sh
@@ -337,7 +337,8 @@ test_expect_success 'expect def_params for query command' '
 # remote-curl.c rather than git.c.  Confirm that we get def_param
 # events from both layers.
 #
-test_expect_success 'expect def_params for remote-curl and _run_dashed_' '
+test_expect_success LIBCURL \
+		'expect def_params for remote-curl and _run_dashed_' '
 	test_when_finished "rm prop.perf actual" &&
 
 	test_config_global "trace2.configParams" "cfg.prop.*" &&
@@ -366,7 +367,8 @@ test_expect_success 'expect def_params for remote-curl and _run_dashed_' '
 # an executable built from http-fetch.c.  Confirm that we get
 # def_param events from both layers.
 #
-test_expect_success 'expect def_params for http-fetch and _run_dashed_' '
+test_expect_success LIBCURL \
+		'expect def_params for http-fetch and _run_dashed_' '
 	test_when_finished "rm prop.perf actual" &&
 
 	test_config_global "trace2.configParams" "cfg.prop.*" &&

From 48c55943c5c7d1ab35fe8af62f656f8e40fe18e5 Mon Sep 17 00:00:00 2001
From: Jeff King <peff@peff.net>
Date: Thu, 12 Sep 2024 05:43:36 -0400
Subject: [PATCH 009/259] ci: drop run-docker scripts

We haven't used these scripts since 4a6e4b9602 (CI: remove Travis CI
support, 2021-11-23), as the GitHub Actions config has support for
directly running jobs within docker containers.

It's possible we might want to resurrect something like this in order to
be more agnostic to the CI platform. But it's not clear exactly what it
would look like. And in the meantime, it's just a maintenance burden as
we make changes to CI config, and is subject to bitrot. In fact it's
already broken; it references ci/install-docker-dependencies.sh, which
went away in 9cdeb34b96 (ci: merge scripts which install dependencies,
2024-04-12).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 ci/run-docker-build.sh | 66 ------------------------------------------
 ci/run-docker.sh       | 47 ------------------------------
 2 files changed, 113 deletions(-)
 delete mode 100755 ci/run-docker-build.sh
 delete mode 100755 ci/run-docker.sh

diff --git a/ci/run-docker-build.sh b/ci/run-docker-build.sh
deleted file mode 100755
index 6cd832efb9cb59..00000000000000
--- a/ci/run-docker-build.sh
+++ /dev/null
@@ -1,66 +0,0 @@
-#!/bin/sh
-#
-# Build and test Git inside container
-#
-# Usage:
-#   run-docker-build.sh <host-user-id>
-#
-
-set -ex
-
-if test $# -ne 1 || test -z "$1"
-then
-	echo >&2 "usage: run-docker-build.sh <host-user-id>"
-	exit 1
-fi
-
-case "$jobname" in
-linux32)
-	switch_cmd="linux32 --32bit i386"
-	;;
-linux-musl)
-	switch_cmd=
-	useradd () { adduser -D "$@"; }
-	;;
-*)
-	exit 1
-	;;
-esac
-
-"${0%/*}/install-docker-dependencies.sh"
-
-# If this script runs inside a docker container, then all commands are
-# usually executed as root. Consequently, the host user might not be
-# able to access the test output files.
-# If a non 0 host user id is given, then create a user "ci" with that
-# user id to make everything accessible to the host user.
-HOST_UID=$1
-if test $HOST_UID -eq 0
-then
-	# Just in case someone does want to run the test suite as root.
-	CI_USER=root
-else
-	CI_USER=ci
-	if test "$(id -u $CI_USER 2>/dev/null)" = $HOST_UID
-	then
-		echo "user '$CI_USER' already exists with the requested ID $HOST_UID"
-	else
-		useradd -u $HOST_UID $CI_USER
-	fi
-fi
-
-# Build and test
-command $switch_cmd su -m -l $CI_USER -c "
-	set -ex
-	export DEVELOPER='$DEVELOPER'
-	export DEFAULT_TEST_TARGET='$DEFAULT_TEST_TARGET'
-	export GIT_PROVE_OPTS='$GIT_PROVE_OPTS'
-	export GIT_TEST_OPTS='$GIT_TEST_OPTS'
-	export GIT_TEST_CLONE_2GB='$GIT_TEST_CLONE_2GB'
-	export MAKEFLAGS='$MAKEFLAGS'
-	export cache_dir='$cache_dir'
-	cd /usr/src/git
-	test -n '$cache_dir' && ln -s '$cache_dir/.prove' t/.prove
-	make
-	make test
-"
diff --git a/ci/run-docker.sh b/ci/run-docker.sh
deleted file mode 100755
index af89d1624a41cb..00000000000000
--- a/ci/run-docker.sh
+++ /dev/null
@@ -1,47 +0,0 @@
-#!/bin/sh
-#
-# Download and run Docker image to build and test Git
-#
-
-. ${0%/*}/lib.sh
-
-case "$jobname" in
-linux32)
-	CI_CONTAINER="daald/ubuntu32:xenial"
-	;;
-linux-musl)
-	CI_CONTAINER=alpine
-	;;
-*)
-	exit 1
-	;;
-esac
-
-docker pull "$CI_CONTAINER"
-
-# Use the following command to debug the docker build locally:
-# <host-user-id> must be 0 if podman is used as drop-in replacement for docker
-# $ docker run -itv "${PWD}:/usr/src/git" --entrypoint /bin/sh "$CI_CONTAINER"
-# root@container:/# export jobname=<jobname>
-# root@container:/# /usr/src/git/ci/run-docker-build.sh <host-user-id>
-
-container_cache_dir=/tmp/container-cache
-
-docker run \
-	--interactive \
-	--env DEVELOPER \
-	--env DEFAULT_TEST_TARGET \
-	--env GIT_PROVE_OPTS \
-	--env GIT_TEST_OPTS \
-	--env GIT_TEST_CLONE_2GB \
-	--env MAKEFLAGS \
-	--env jobname \
-	--env cache_dir="$container_cache_dir" \
-	--volume "${PWD}:/usr/src/git" \
-	--volume "$cache_dir:$container_cache_dir" \
-	"$CI_CONTAINER" \
-	/usr/src/git/ci/run-docker-build.sh $(id -u $USER)
-
-check_unignored_build_artifacts
-
-save_good_tree

From e24a7bc7f028bc9b9a54167276c0f15bbc773631 Mon Sep 17 00:00:00 2001
From: Jeff King <peff@peff.net>
Date: Thu, 12 Sep 2024 05:45:37 -0400
Subject: [PATCH 010/259] ci: unify ubuntu and ubuntu32 dependencies

The script to install dependencies has two separate entries for 32-bit
and 64-bit Ubuntu systems. This increases the maintenance burden since
both should need roughly the same packages.

That hasn't been too bad so far because we've stayed on the same 32-bit
image since 2017. Trying to move to a newer image revealed several
problems with the linux32 job:

  - newer images complain about using "linux32 --32bit i386", due to
    seccomp restrictions. We can loosen these with a docker option, but
    I don't think running it is even doing anything. We use it only for
    pretending to "apt" that we're on a 32-bit machine, but inside the
    container image apt is already configured as a 32-bit system (even
    though the kernel outside the container is obviously 64-bit).  Using
    the same apt invocation for both architectures just gets rid of this
    call entirely.

  - we set DEBIAN_FRONTEND to avoid hanging on packages that ask the
    user questions. This wasn't a problem on the old image, but it is on
    newer ones. The 64-bit stanza handles this already.

    As a bonus, the 64-bit stanza uses "apt -q" instead of redirecting
    output to /dev/null. This would have saved me a lot of debugging
    time trying to figure out why it was hanging. :)

  - the old image seems to have zlib-dev installed by default, but newer
    ones do not.

In addition, there were probably many tests being skipped on the 32-bit
build because we didn't have support packages installed (e.g., gpg). Now
we'll run them.

We do need to keep some parts split off just for 64-bit systems: our p4
and lfs installs reference x86_64/amd64 binaries. The downloaded jgit
should work in theory, since it's just a jar file embedded in a shell
script that relies on the system java. But the system java in our image
is too old, so I've left it as 64-bit only for now.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 ci/install-dependencies.sh | 34 ++++++++++++++++------------------
 1 file changed, 16 insertions(+), 18 deletions(-)

diff --git a/ci/install-dependencies.sh b/ci/install-dependencies.sh
index b59fd7c1fd6af1..3b9b4208882681 100755
--- a/ci/install-dependencies.sh
+++ b/ci/install-dependencies.sh
@@ -33,7 +33,7 @@ fedora-*)
 	dnf -yq update >/dev/null &&
 	dnf -yq install make gcc findutils diffutils perl python3 gettext zlib-devel expat-devel openssl-devel curl-devel pcre2-devel >/dev/null
 	;;
-ubuntu-*)
+ubuntu-*|ubuntu32-*)
 	# Required so that apt doesn't wait for user input on certain packages.
 	export DEBIAN_FRONTEND=noninteractive
 
@@ -45,25 +45,23 @@ ubuntu-*)
 		libemail-valid-perl libio-pty-perl libio-socket-ssl-perl libnet-smtp-ssl-perl libdbd-sqlite3-perl libcgi-pm-perl \
 		${CC_PACKAGE:-${CC:-gcc}} $PYTHON_PACKAGE
 
-	mkdir --parents "$CUSTOM_PATH"
-	wget --quiet --directory-prefix="$CUSTOM_PATH" \
-		"$P4WHENCE/bin.linux26x86_64/p4d" "$P4WHENCE/bin.linux26x86_64/p4"
-	chmod a+x "$CUSTOM_PATH/p4d" "$CUSTOM_PATH/p4"
+	case "$distro" in
+	ubuntu-*)
+		mkdir --parents "$CUSTOM_PATH"
 
-	wget --quiet "$LFSWHENCE/git-lfs-linux-amd64-$LINUX_GIT_LFS_VERSION.tar.gz"
-	tar -xzf "git-lfs-linux-amd64-$LINUX_GIT_LFS_VERSION.tar.gz" \
-		-C "$CUSTOM_PATH" --strip-components=1 "git-lfs-$LINUX_GIT_LFS_VERSION/git-lfs"
-	rm "git-lfs-linux-amd64-$LINUX_GIT_LFS_VERSION.tar.gz"
+		wget --quiet --directory-prefix="$CUSTOM_PATH" \
+			"$P4WHENCE/bin.linux26x86_64/p4d" "$P4WHENCE/bin.linux26x86_64/p4"
+		chmod a+x "$CUSTOM_PATH/p4d" "$CUSTOM_PATH/p4"
 
-	wget --quiet "$JGITWHENCE" --output-document="$CUSTOM_PATH/jgit"
-	chmod a+x "$CUSTOM_PATH/jgit"
-	;;
-ubuntu32-*)
-	sudo linux32 --32bit i386 sh -c '
-		apt update >/dev/null &&
-		apt install -y build-essential libcurl4-openssl-dev \
-			libssl-dev libexpat-dev gettext python >/dev/null
-	'
+		wget --quiet "$LFSWHENCE/git-lfs-linux-amd64-$LINUX_GIT_LFS_VERSION.tar.gz"
+		tar -xzf "git-lfs-linux-amd64-$LINUX_GIT_LFS_VERSION.tar.gz" \
+			-C "$CUSTOM_PATH" --strip-components=1 "git-lfs-$LINUX_GIT_LFS_VERSION/git-lfs"
+		rm "git-lfs-linux-amd64-$LINUX_GIT_LFS_VERSION.tar.gz"
+
+		wget --quiet "$JGITWHENCE" --output-document="$CUSTOM_PATH/jgit"
+		chmod a+x "$CUSTOM_PATH/jgit"
+		;;
+	esac
 	;;
 macos-*)
 	export HOMEBREW_NO_AUTO_UPDATE=1 HOMEBREW_NO_INSTALL_CLEANUP=1

From 9ce2e99c7d5518b622c3017cd12aa254c853df4f Mon Sep 17 00:00:00 2001
From: Jeff King <peff@peff.net>
Date: Thu, 12 Sep 2024 05:47:30 -0400
Subject: [PATCH 011/259] ci: use more recent linux32 image

The Xenial image we're using was released more than 8 years ago. This is
a problem for using some recent GitHub Actions scripts, as they require
Node.js 20, and all of the binaries they ship need glibc 2.28 or later.
We're not using them yet, but moving forward prepares us for a future
patch which will.

Xenial was actually the last official 32-bit Ubuntu release, but you can
still find i386 images for more recent releases. This patch uses Focal,
which was released in 2020 (and is the oldest one with glibc 2.28).

There are two small downsides here:

  - while Xenial is pretty old, it is still in LTS support until April
    2026. So there's probably some value in testing with such an old
    system, and we're losing that.

  - there are no i386 subversion packages in the Focal repository. So we
    won't be able to test that (OTOH, we had never tested it until the
    previous patch which unified the 32/64-bit dependency code).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 .github/workflows/main.yml |  4 ++--
 ci/install-dependencies.sh | 11 ++++++++++-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 97f9b063109411..db8e8f75a43d01 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -339,8 +339,8 @@ jobs:
           image: alpine
           distro: alpine-latest
         - jobname: linux32
-          image: daald/ubuntu32:xenial
-          distro: ubuntu32-16.04
+          image: i386/ubuntu:focal
+          distro: ubuntu32-20.04
         - jobname: pedantic
           image: fedora
           distro: fedora-latest
diff --git a/ci/install-dependencies.sh b/ci/install-dependencies.sh
index 3b9b4208882681..d04f2a490beca8 100755
--- a/ci/install-dependencies.sh
+++ b/ci/install-dependencies.sh
@@ -37,9 +37,18 @@ ubuntu-*|ubuntu32-*)
 	# Required so that apt doesn't wait for user input on certain packages.
 	export DEBIAN_FRONTEND=noninteractive
 
+	case "$distro" in
+	ubuntu-*)
+		SVN='libsvn-perl subversion'
+		;;
+	*)
+		SVN=
+		;;
+	esac
+
 	sudo apt-get -q update
 	sudo apt-get -q -y install \
-		language-pack-is libsvn-perl apache2 cvs cvsps git gnupg subversion \
+		language-pack-is apache2 cvs cvsps git gnupg $SVN \
 		make libssl-dev libcurl4-openssl-dev libexpat-dev wget sudo default-jre \
 		tcl tk gettext zlib1g-dev perl-modules liberror-perl libauthen-sasl-perl \
 		libemail-valid-perl libio-pty-perl libio-socket-ssl-perl libnet-smtp-ssl-perl libdbd-sqlite3-perl libcgi-pm-perl \

From 9c261856c91f9312a285cdc6ff863997f0cdf98a Mon Sep 17 00:00:00 2001
From: Jeff King <peff@peff.net>
Date: Thu, 12 Sep 2024 05:48:41 -0400
Subject: [PATCH 012/259] ci: use regular action versions for linux32 job

The linux32 job runs inside a docker container with a 32-bit libc, etc.
This breaks any GitHub Actions scripts that are implemented in
javascript, because they ship with their own 64-bit version of Node.js
that's dynamically linked. They'll fail with a message like:

    exec /__e/node20/bin/node: no such file or directory

because they can't find the runtime linker.

This hasn't been a problem until recently because we special-case older,
non-javascript versions of these actions for the linux32 job. But it
recently became an issue when our old version of actions/upload-artifact
was deprecated, causing the job to fail. We worked around that in
90f2c7240c (ci: remove 'Upload failed tests' directories' step from
linux32 jobs, 2024-09-09), but it meant a loss of functionality for that
job. And we may eventually run into the same deprecation problem with
actions/checkout, which can't just be removed.

We can solve the linking issue by installing the 64-bit libc and stdc++
packages before doing anything else. Coupled with the switch to a more
recent image in the previous patch, that lets us remove the
special-casing of the action scripts entirely.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 .github/workflows/main.yml | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index db8e8f75a43d01..916a64b6736d1c 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -350,17 +350,17 @@ jobs:
     runs-on: ubuntu-latest
     container: ${{matrix.vector.image}}
     steps:
-    - uses: actions/checkout@v4
-      if: matrix.vector.jobname != 'linux32'
-    - uses: actions/checkout@v1 # cannot be upgraded because Node.js Actions aren't supported in this container
+    - name: prepare libc6 for actions
       if: matrix.vector.jobname == 'linux32'
+      run: apt -q update && apt -q -y install libc6-amd64 lib64stdc++6
+    - uses: actions/checkout@v4
     - run: ci/install-dependencies.sh
     - run: ci/run-build-and-tests.sh
     - name: print test failures
       if: failure() && env.FAILED_TEST_ARTIFACTS != ''
       run: ci/print-test-failures.sh
     - name: Upload failed tests' directories
-      if: failure() && env.FAILED_TEST_ARTIFACTS != '' && matrix.vector.jobname != 'linux32'
+      if: failure() && env.FAILED_TEST_ARTIFACTS != ''
       uses: actions/upload-artifact@v4
       with:
         name: failed-tests-${{matrix.vector.jobname}}

From 7cd8f1cc6e17af54fb78768c259a615b1ccc0205 Mon Sep 17 00:00:00 2001
From: Patrick Steinhardt <ps@pks.im>
Date: Fri, 13 Sep 2024 07:52:51 +0200
Subject: [PATCH 013/259] ci: add Ubuntu 16.04 job to GitLab CI

In the preceding commits we had to convert the linux32 job to be based
on Ubuntu 20.04 instead of Ubuntu 16.04 due to a limitation in GitHub
Workflows. This was the only job left that still tested against this old
but supported Ubuntu version, and we have no other jobs that test with a
comparatively old Linux distribution.

Add a new job to GitLab CI that tests with Ubuntu 16.04 to cover the
resulting test gap. GitLab doesn't modify Docker images in the same way
GitHub does and thus doesn't fall prey to the same issue. There are two
compatibility issues uncovered by this:

  - Ubuntu 16.04 does not support HTTP/2 in Apache. We thus cannot set
    `GIT_TEST_HTTPD=true`, which would otherwise cause us to fail when
    Apache fails to start.

  - Ubuntu 16.04 cannot use recent JGit versions as they depend on a
    more recent Java runtime than we have available. We thus disable
    installing any kind of optional dependencies that do not come from
    the package manager.

These two restrictions are fine though, as we only really care about
whether Git compiles and runs on such old distributions in the first
place.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 .gitlab-ci.yml             | 3 +++
 ci/install-dependencies.sh | 5 +++++
 ci/lib.sh                  | 9 ++++++++-
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 37b991e08079fc..c4c45dad2f956f 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -25,6 +25,9 @@ test:linux:
       fi
   parallel:
     matrix:
+      - jobname: linux-old
+        image: ubuntu:16.04
+        CC: gcc
       - jobname: linux-sha256
         image: ubuntu:latest
         CC: clang
diff --git a/ci/install-dependencies.sh b/ci/install-dependencies.sh
index d04f2a490beca8..e2c6ef0f662b9e 100755
--- a/ci/install-dependencies.sh
+++ b/ci/install-dependencies.sh
@@ -55,6 +55,11 @@ ubuntu-*|ubuntu32-*)
 		${CC_PACKAGE:-${CC:-gcc}} $PYTHON_PACKAGE
 
 	case "$distro" in
+	ubuntu-16.04)
+		# Does not support JGit, but we also don't really care about
+		# the others. We rather care whether Git still compiles and
+		# runs fine overall.
+		;;
 	ubuntu-*)
 		mkdir --parents "$CUSTOM_PATH"
 
diff --git a/ci/lib.sh b/ci/lib.sh
index 51f8f59a296132..74b430be2387ac 100755
--- a/ci/lib.sh
+++ b/ci/lib.sh
@@ -336,7 +336,14 @@ ubuntu-*)
 	fi
 	MAKEFLAGS="$MAKEFLAGS PYTHON_PATH=/usr/bin/$PYTHON_PACKAGE"
 
-	export GIT_TEST_HTTPD=true
+	case "$distro" in
+	ubuntu-16.04)
+		# Apache is too old for HTTP/2.
+		;;
+	*)
+		export GIT_TEST_HTTPD=true
+		;;
+	esac
 
 	# The Linux build installs the defined dependency versions below.
 	# The OS X build installs much more recent versions, whichever

From d6bf6527ebfab4899d52d5662f3c5054195e6415 Mon Sep 17 00:00:00 2001
From: Junio C Hamano <gitster@pobox.com>
Date: Mon, 16 Sep 2024 15:12:06 -0700
Subject: [PATCH 014/259] Revert "Merge branch 'jc/patch-id' into maint-2.46"

This reverts commit 41c952ebacf7e3369e7bee721f768114d65e50c4,
reversing changes made to 712d970c0145b95ce655773e7cd1676f09dfd215.
Keeping a known breakage for now is better than introducing new
regression(s).
---
 builtin/patch-id.c  | 93 ++++++++++-----------------------------------
 t/t4204-patch-id.sh | 40 -------------------
 2 files changed, 21 insertions(+), 112 deletions(-)

diff --git a/builtin/patch-id.c b/builtin/patch-id.c
index 35c1179f7e94ba..d790ae6354b415 100644
--- a/builtin/patch-id.c
+++ b/builtin/patch-id.c
@@ -7,9 +7,10 @@
 #include "parse-options.h"
 #include "setup.h"
 
-static void flush_current_id(struct object_id *id, struct object_id *result)
+static void flush_current_id(int patchlen, struct object_id *id, struct object_id *result)
 {
-	printf("%s %s\n", oid_to_hex(result), oid_to_hex(id));
+	if (patchlen)
+		printf("%s %s\n", oid_to_hex(result), oid_to_hex(id));
 }
 
 static int remove_space(char *line)
@@ -59,27 +60,9 @@ static int scan_hunk_header(const char *p, int *p_before, int *p_after)
 	return 1;
 }
 
-/*
- * flag bits to control get_one_patchid()'s behaviour.
- *
- * STABLE/VERBATIM are given from the command line option as
- * --stable/--verbatim.  FIND_HEADER conveys the internal state
- * maintained by the caller to allow the function to avoid mistaking
- * lines of log message before seeing the "diff" part as the beginning
- * of the next patch.
- */
-enum {
-	GOPID_STABLE = (1<<0),		/* --stable */
-	GOPID_VERBATIM = (1<<1),	/* --verbatim */
-	GOPID_FIND_HEADER = (1<<2),	/* stop at the beginning of patch message */
-};
-
 static int get_one_patchid(struct object_id *next_oid, struct object_id *result,
-			   struct strbuf *line_buf, unsigned flags)
+			   struct strbuf *line_buf, int stable, int verbatim)
 {
-	int stable = flags & GOPID_STABLE;
-	int verbatim = flags & GOPID_VERBATIM;
-	int find_header = flags & GOPID_FIND_HEADER;
 	int patchlen = 0, found_next = 0;
 	int before = -1, after = -1;
 	int diff_is_binary = 0;
@@ -94,40 +77,24 @@ static int get_one_patchid(struct object_id *next_oid, struct object_id *result,
 		const char *p = line;
 		int len;
 
-		/*
-		 * The caller hasn't seen us find a patch header and
-		 * return to it, or we have started processing patch
-		 * and may encounter the beginning of the next patch.
-		 */
-		if (find_header) {
-			/*
-			 * If we see a line that begins with "<object name>",
-			 * "commit <object name>" or "From <object name>", it is
-			 * the beginning of a patch.  Return to the caller, as
-			 * we are done with the one we have been processing.
-			 */
-			if (skip_prefix(line, "commit ", &p))
-				;
-			else if (skip_prefix(line, "From ", &p))
-				;
-			if (!get_oid_hex(p, next_oid)) {
-				if (verbatim)
-					the_hash_algo->update_fn(&ctx, line, strlen(line));
-				found_next = 1;
-				break;
-			}
+		/* Possibly skip over the prefix added by "log" or "format-patch" */
+		if (!skip_prefix(line, "commit ", &p) &&
+		    !skip_prefix(line, "From ", &p) &&
+		    starts_with(line, "\\ ") && 12 < strlen(line)) {
+			if (verbatim)
+				the_hash_algo->update_fn(&ctx, line, strlen(line));
+			continue;
+		}
+
+		if (!get_oid_hex(p, next_oid)) {
+			found_next = 1;
+			break;
 		}
 
 		/* Ignore commit comments */
 		if (!patchlen && !starts_with(line, "diff "))
 			continue;
 
-		/*
-		 * We are past the commit log message.  Prepare to
-		 * stop at the beginning of the next patch header.
-		 */
-		find_header = 1;
-
 		/* Parsing diff header?  */
 		if (before == -1) {
 			if (starts_with(line, "GIT binary patch") ||
@@ -160,16 +127,6 @@ static int get_one_patchid(struct object_id *next_oid, struct object_id *result,
 				break;
 		}
 
-		/*
-		 * A hunk about an incomplete line may have this
-		 * marker at the end, which should just be ignored.
-		 */
-		if (starts_with(line, "\\ ") && 12 < strlen(line)) {
-			if (verbatim)
-				the_hash_algo->update_fn(&ctx, line, strlen(line));
-			continue;
-		}
-
 		if (diff_is_binary) {
 			if (starts_with(line, "diff ")) {
 				diff_is_binary = 0;
@@ -216,20 +173,17 @@ static int get_one_patchid(struct object_id *next_oid, struct object_id *result,
 	return patchlen;
 }
 
-static void generate_id_list(unsigned flags)
+static void generate_id_list(int stable, int verbatim)
 {
 	struct object_id oid, n, result;
 	int patchlen;
 	struct strbuf line_buf = STRBUF_INIT;
 
 	oidclr(&oid, the_repository->hash_algo);
-	flags |= GOPID_FIND_HEADER;
 	while (!feof(stdin)) {
-		patchlen = get_one_patchid(&n, &result, &line_buf, flags);
-		if (patchlen)
-			flush_current_id(&oid, &result);
+		patchlen = get_one_patchid(&n, &result, &line_buf, stable, verbatim);
+		flush_current_id(patchlen, &oid, &result);
 		oidcpy(&oid, &n);
-		flags &= ~GOPID_FIND_HEADER;
 	}
 	strbuf_release(&line_buf);
 }
@@ -265,7 +219,6 @@ int cmd_patch_id(int argc, const char **argv, const char *prefix)
 	/* if nothing is set, default to unstable */
 	struct patch_id_opts config = {0, 0};
 	int opts = 0;
-	unsigned flags = 0;
 	struct option builtin_patch_id_options[] = {
 		OPT_CMDMODE(0, "unstable", &opts,
 		    N_("use the unstable patch-id algorithm"), 1),
@@ -297,11 +250,7 @@ int cmd_patch_id(int argc, const char **argv, const char *prefix)
 	if (!the_hash_algo)
 		repo_set_hash_algo(the_repository, GIT_HASH_SHA1);
 
-	if (opts ? opts > 1 : config.stable)
-		flags |= GOPID_STABLE;
-	if (opts ? opts == 3 : config.verbatim)
-		flags |= GOPID_VERBATIM;
-	generate_id_list(flags);
-
+	generate_id_list(opts ? opts > 1 : config.stable,
+			 opts ? opts == 3 : config.verbatim);
 	return 0;
 }
diff --git a/t/t4204-patch-id.sh b/t/t4204-patch-id.sh
index dc8ddb10affcea..605faea0c7baae 100755
--- a/t/t4204-patch-id.sh
+++ b/t/t4204-patch-id.sh
@@ -114,46 +114,6 @@ test_expect_success 'patch-id supports git-format-patch output' '
 	test "$2" = $(git rev-parse HEAD)
 '
 
-test_expect_success 'patch-id computes the same for various formats' '
-	# This test happens to consider "git log -p -1" output
-	# the canonical input format, so use it as the norm.
-	git log -1 -p same >log-p.output &&
-	git patch-id <log-p.output >expect &&
-
-	# format-patch begins with "From <commit object name>"
-	git format-patch -1 --stdout same >format-patch.output &&
-	git patch-id <format-patch.output >actual &&
-	test_cmp actual expect &&
-
-	# "diff-tree --stdin -p" begins with "<commit object name>"
-	same=$(git rev-parse same) &&
-	echo $same | git diff-tree --stdin -p >diff-tree.output &&
-	git patch-id <diff-tree.output >actual &&
-	test_cmp actual expect &&
-
-	# "diff-tree --stdin -v -p" begins with "commit <commit object name>"
-	echo $same | git diff-tree --stdin -p -v >diff-tree-v.output &&
-	git patch-id <diff-tree-v.output >actual &&
-	test_cmp actual expect
-'
-
-hash=$(git rev-parse same:)
-for cruft in "$hash" "commit $hash is bad" "From $hash status"
-do
-	test_expect_success "patch-id with <$cruft> in log message" '
-		git format-patch -1 --stdout same >patch-0 &&
-		git patch-id <patch-0 >expect &&
-
-		{
-			sed -e "/^$/q" patch-0 &&
-			printf "random message\n%s\n\n" "$cruft" &&
-			sed -e "1,/^$/d" patch-0
-		} >patch-cruft &&
-		git patch-id <patch-cruft >actual &&
-		test_cmp actual expect
-	'
-done
-
 test_expect_success 'whitespace is irrelevant in footer' '
 	get_patch_id main &&
 	git checkout same &&

From e29e5cf288141a51823bbd6d2da90105c42a10c1 Mon Sep 17 00:00:00 2001
From: Junio C Hamano <gitster@pobox.com>
Date: Mon, 16 Sep 2024 15:18:58 -0700
Subject: [PATCH 015/259] Start preparing for Git 2.46.2

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 Documentation/RelNotes/2.46.2.txt | 11 +++++++++++
 GIT-VERSION-GEN                   |  2 +-
 RelNotes                          |  2 +-
 3 files changed, 13 insertions(+), 2 deletions(-)
 create mode 100644 Documentation/RelNotes/2.46.2.txt

diff --git a/Documentation/RelNotes/2.46.2.txt b/Documentation/RelNotes/2.46.2.txt
new file mode 100644
index 00000000000000..51471e54005835
--- /dev/null
+++ b/Documentation/RelNotes/2.46.2.txt
@@ -0,0 +1,11 @@
+Git 2.46.2 Release Notes
+========================
+
+This release is primarily to merge changes to unbreak the 32-bit
+GitHub actions jobs we use for CI testing, so that we can release
+real fixes for the 2.46.x track after they pass CI.
+
+It also reverts the "git patch-id" change that went into 2.46.1,
+as it seems to have got a regression reported (I haven't verified,
+but it is better to keep a known breakage than adding an unintended
+regression).
diff --git a/GIT-VERSION-GEN b/GIT-VERSION-GEN
index 55850912d13034..efe61fd1f80127 100755
--- a/GIT-VERSION-GEN
+++ b/GIT-VERSION-GEN
@@ -1,7 +1,7 @@
 #!/bin/sh
 
 GVF=GIT-VERSION-FILE
-DEF_VER=v2.46.1
+DEF_VER=v2.46.2-pre
 
 LF='
 '
diff --git a/RelNotes b/RelNotes
index 89b65f22b19959..0dfe046c8855e5 120000
--- a/RelNotes
+++ b/RelNotes
@@ -1 +1 @@
-Documentation/RelNotes/2.46.1.txt
\ No newline at end of file
+Documentation/RelNotes/2.46.2.txt
\ No newline at end of file

From 4f71522dfb7fc53eff569023303980c66114b1bc Mon Sep 17 00:00:00 2001
From: Junio C Hamano <gitster@pobox.com>
Date: Fri, 20 Sep 2024 09:10:24 -0700
Subject: [PATCH 016/259] Git 2.46.2

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 Documentation/RelNotes/2.46.2.txt | 12 ++++++++++++
 GIT-VERSION-GEN                   |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/Documentation/RelNotes/2.46.2.txt b/Documentation/RelNotes/2.46.2.txt
index 51471e54005835..613386878d44c9 100644
--- a/Documentation/RelNotes/2.46.2.txt
+++ b/Documentation/RelNotes/2.46.2.txt
@@ -9,3 +9,15 @@ It also reverts the "git patch-id" change that went into 2.46.1,
 as it seems to have got a regression reported (I haven't verified,
 but it is better to keep a known breakage than adding an unintended
 regression).
+
+Other than that, a handful of minor bugfixes are included.
+
+ * In a few corner cases "git diff --exit-code" failed to report
+   "changes" (e.g., renamed without any content change), which has
+   been corrected.
+
+ * Cygwin does have /dev/tty support that is needed by things like
+   single-key input mode.
+
+ * The interpret-trailers command failed to recognise the end of the
+   message when the commit log ends in an incomplete line.
diff --git a/GIT-VERSION-GEN b/GIT-VERSION-GEN
index efe61fd1f80127..05fa12fec794eb 100755
--- a/GIT-VERSION-GEN
+++ b/GIT-VERSION-GEN
@@ -1,7 +1,7 @@
 #!/bin/sh
 
 GVF=GIT-VERSION-FILE
-DEF_VER=v2.46.2-pre
+DEF_VER=v2.46.2
 
 LF='
 '

From f09bdca352a059162515b93b17b4d51b39819bde Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 19 Jan 2023 13:40:31 +0100
Subject: [PATCH 017/259] gitk(Windows): avoid inadvertently calling
 executables in the worktree

Just like CVE-2022-41953 for Git GUI, there exists a vulnerability of
`gitk` where it looks for `taskkill.exe` in the current directory before
searching `PATH`.

Note that the many `exec git` calls are unaffected, due to an obscure
quirk in Tcl's `exec` function. Typically, `git.exe` lives next to
`wish.exe` (i.e. the program that is run to execute `gitk` or Git GUI)
in Git for Windows, and that is the saving grace for `git.exe because
`exec` searches the directory where `wish.exe` lives even before the
current directory, according to
https://www.tcl-lang.org/man/tcl/TclCmd/exec.htm#M24:

	If a directory name was not specified as part of the application
	name, the following directories are automatically searched in
	order when attempting to locate the application:

	    The directory from which the Tcl executable was loaded.

	    The current directory.

	    The Windows 32-bit system directory.

	    The Windows home directory.

	    The directories listed in the path.

The same is not true, however, for `taskkill.exe`: it lives in the
Windows system directory (never mind the 32-bit, Tcl's documentation is
outdated on that point, it really means `C:\Windows\system32`).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 gitk-git/gitk | 135 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 135 insertions(+)

diff --git a/gitk-git/gitk b/gitk-git/gitk
index 7a087f123d7563..076ca3687d7653 100755
--- a/gitk-git/gitk
+++ b/gitk-git/gitk
@@ -9,6 +9,141 @@ exec wish "$0" -- "$@"
 
 package require Tk
 
+######################################################################
+##
+## Enabling platform-specific code paths
+
+proc is_MacOSX {} {
+	if {[tk windowingsystem] eq {aqua}} {
+		return 1
+	}
+	return 0
+}
+
+proc is_Windows {} {
+	if {$::tcl_platform(platform) eq {windows}} {
+		return 1
+	}
+	return 0
+}
+
+set _iscygwin {}
+proc is_Cygwin {} {
+	global _iscygwin
+	if {$_iscygwin eq {}} {
+		if {[string match "CYGWIN_*" $::tcl_platform(os)]} {
+			set _iscygwin 1
+		} else {
+			set _iscygwin 0
+		}
+	}
+	return $_iscygwin
+}
+
+######################################################################
+##
+## PATH lookup
+
+set _search_path {}
+proc _which {what args} {
+	global env _search_exe _search_path
+
+	if {$_search_path eq {}} {
+		if {[is_Cygwin] && [regexp {^(/|\.:)} $env(PATH)]} {
+			set _search_path [split [exec cygpath \
+				--windows \
+				--path \
+				--absolute \
+				$env(PATH)] {;}]
+			set _search_exe .exe
+		} elseif {[is_Windows]} {
+			set gitguidir [file dirname [info script]]
+			regsub -all ";" $gitguidir "\\;" gitguidir
+			set env(PATH) "$gitguidir;$env(PATH)"
+			set _search_path [split $env(PATH) {;}]
+			# Skip empty `PATH` elements
+			set _search_path [lsearch -all -inline -not -exact \
+				$_search_path ""]
+			set _search_exe .exe
+		} else {
+			set _search_path [split $env(PATH) :]
+			set _search_exe {}
+		}
+	}
+
+	if {[is_Windows] && [lsearch -exact $args -script] >= 0} {
+		set suffix {}
+	} else {
+		set suffix $_search_exe
+	}
+
+	foreach p $_search_path {
+		set p [file join $p $what$suffix]
+		if {[file exists $p]} {
+			return [file normalize $p]
+		}
+	}
+	return {}
+}
+
+proc sanitize_command_line {command_line from_index} {
+	set i $from_index
+	while {$i < [llength $command_line]} {
+		set cmd [lindex $command_line $i]
+		if {[file pathtype $cmd] ne "absolute"} {
+			set fullpath [_which $cmd]
+			if {$fullpath eq ""} {
+				throw {NOT-FOUND} "$cmd not found in PATH"
+			}
+			lset command_line $i $fullpath
+		}
+
+		# handle piped commands, e.g. `exec A | B`
+		for {incr i} {$i < [llength $command_line]} {incr i} {
+			if {[lindex $command_line $i] eq "|"} {
+				incr i
+				break
+			}
+		}
+	}
+	return $command_line
+}
+
+# Override `exec` to avoid unsafe PATH lookup
+
+rename exec real_exec
+
+proc exec {args} {
+	# skip options
+	for {set i 0} {$i < [llength $args]} {incr i} {
+		set arg [lindex $args $i]
+		if {$arg eq "--"} {
+			incr i
+			break
+		}
+		if {[string range $arg 0 0] ne "-"} {
+			break
+		}
+	}
+	set args [sanitize_command_line $args $i]
+	uplevel 1 real_exec $args
+}
+
+# Override `open` to avoid unsafe PATH lookup
+
+rename open real_open
+
+proc open {args} {
+	set arg0 [lindex $args 0]
+	if {[string range $arg0 0 0] eq "|"} {
+		set command_line [string trim [string range $arg0 1 end]]
+		lset args 0 "| [sanitize_command_line $command_line 0]"
+	}
+	uplevel 1 real_open $args
+}
+
+# End of safe PATH lookup stuff
+
 proc hasworktree {} {
     return [expr {[exec git rev-parse --is-bare-repository] == "false" &&
                   [exec git rev-parse --is-inside-git-dir] == "false"}]

From f35db516d6a537194f1a32b9efe9ccb9d3055a38 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 24 Sep 2024 08:47:39 +0200
Subject: [PATCH 018/259] ci: work around a problem with HTTP/2 vs libcurl
 v8.10.0

As reported in https://lore.kernel.org/git/ZuPKvYP9ZZ2mhb4m@pks.im/,
libcurl v8.10.0 had a regression that was picked up by Git's t5559.30
"large fetch-pack requests can be sent using chunked encoding".

This bug was fixed in libcurl v8.10.1.

Sadly, the macos-13 runner image was updated in the brief window between
these two libcurl versions, breaking each and every CI build, as
reported at https://github.com/git-for-windows/git/issues/5159.

This would usually not matter, we would just ignore the failing CI
builds until the macos-13 runner image is rebuilt in a couple of days,
and then the CI builds would succeed again.

However.

As has become the custom, a surprise Git version was released, and now
that Git for Windows wants to follow suit, since Git for Windows has
this custom of trying to never release a version with a failing CI
build, we _must_ work around it.

This patch implements this work-around, basically for the sake of Git
for Windows v2.46.2's CI build.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t5551-http-fetch-smart.sh | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/t/t5551-http-fetch-smart.sh b/t/t5551-http-fetch-smart.sh
index 7b5ab0eae16012..85fd0a197d0356 100755
--- a/t/t5551-http-fetch-smart.sh
+++ b/t/t5551-http-fetch-smart.sh
@@ -381,7 +381,15 @@ test_expect_success CMDLINE_LIMIT \
 	)
 '
 
-test_expect_success 'large fetch-pack requests can be sent using chunked encoding' '
+# This is a temporary work-around for libcurl v8.10.0 on the macos-* runners;
+# see https://github.com/git-for-windows/git/issues/5159 for full details
+test_lazy_prereq UNBROKEN_HTTP2 '
+	test "$HTTP_PROTO" = HTTP/2 &&
+	test -z "$(brew info -q curl 2>/dev/null |
+		sed -n "/^Installed/{N;s/.*8\\.10\\.0.*/BROKEN HTTP2/p;}")"
+'
+
+test_expect_success UNBROKEN_HTTP2 'large fetch-pack requests can be sent using chunked encoding' '
 	GIT_TRACE_CURL=true git -c http.postbuffer=65536 \
 		clone --bare "$HTTPD_URL/smart/repo.git" split.git 2>err &&
 	{

From e346cc029c847a9c4d4aedba324caf1efbf3b8d3 Mon Sep 17 00:00:00 2001
From: Junio C Hamano <gitster@pobox.com>
Date: Fri, 13 Sep 2024 12:26:41 -0700
Subject: [PATCH 019/259] t5512.40 sometimes dies by SIGPIPE

The last test in t5512 we recently added seems to be flaky.
Running

    $ make && cd t && sh ./t5512-ls-remote.sh --stress

shows that "git ls-remote foo::bar" exited with status 141, which
means we got a SIGPIPE.  This test piece was introduced by 9e89dcb6
(builtin/ls-remote: fall back to SHA1 outside of a repo, 2024-08-02)
and is pretty much independent from all other tests in the script
(it can even run standalone with everything before it removed).

The transport-helper.c:get_helper() function tries to write to the
helper.  As we can see the helper script is very short and can exit
even before it reads anything, when get_helper() tries to give the
first command, "capabilities", the helper may already be gone.

A trivial fix, presented here, is to make sure that the helper reads
the first command it is given, as what it writes later is a response
to that command.

I however would wonder if the interactions with the helper initiated
by get_helper() should be done on a non-blocking I/O (we do check
the return value from our write(2) system calls, do we?).

Backported-from: e1e0d305c41 (t5512.40 sometimes dies by SIGPIPE, 2024-09-13)
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t5512-ls-remote.sh | 1 +
 1 file changed, 1 insertion(+)

diff --git a/t/t5512-ls-remote.sh b/t/t5512-ls-remote.sh
index bc442ec221da93..3a67992a7dc086 100755
--- a/t/t5512-ls-remote.sh
+++ b/t/t5512-ls-remote.sh
@@ -405,6 +405,7 @@ test_expect_success 'v0 clients can handle multiple symrefs' '
 test_expect_success 'helper with refspec capability fails gracefully' '
 	mkdir test-bin &&
 	write_script test-bin/git-remote-foo <<-EOF &&
+	read capabilities
 	echo import
 	echo refspec ${SQ}*:*${SQ}
 	EOF

From 0d5ed899b245f9190290969ea0ef863917cde932 Mon Sep 17 00:00:00 2001
From: Sverre Rabbelier <srabbelier@gmail.com>
Date: Sun, 24 Jul 2011 15:54:04 +0200
Subject: [PATCH 020/259] t9350: point out that refs are not updated correctly

This happens only when the corresponding commits are not exported in
the current fast-export run. This can happen either when the relevant
commit is already marked, or when the commit is explicitly marked
as UNINTERESTING with a negative ref by another argument.

This breaks fast-export basec remote helpers.

Signed-off-by: Sverre Rabbelier <srabbelier@gmail.com>
---
 t/t9350-fast-export.sh | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/t/t9350-fast-export.sh b/t/t9350-fast-export.sh
index 1eb035ee4ce547..f63094d2da280e 100755
--- a/t/t9350-fast-export.sh
+++ b/t/t9350-fast-export.sh
@@ -801,4 +801,15 @@ test_expect_success 'fast-export handles --end-of-options' '
 	test_cmp expect actual
 '
 
+cat > expected << EOF
+reset refs/heads/master
+from $(git rev-parse master)
+
+EOF
+
+test_expect_failure 'refs are updated even if no commits need to be exported' '
+	git fast-export master..master > actual &&
+	test_cmp expected actual
+'
+
 test_done

From fc564e360ec256a23c54c42fd66b197b5e4a4683 Mon Sep 17 00:00:00 2001
From: Sverre Rabbelier <srabbelier@gmail.com>
Date: Sat, 28 Aug 2010 20:49:01 -0500
Subject: [PATCH 021/259] transport-helper: add trailing --

[PT: ensure we add an additional element to the argv array]

Signed-off-by: Sverre Rabbelier <srabbelier@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 transport-helper.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/transport-helper.c b/transport-helper.c
index 09b3560ffdc41e..dbff8362a6123c 100644
--- a/transport-helper.c
+++ b/transport-helper.c
@@ -488,6 +488,8 @@ static int get_exporter(struct transport *transport,
 	for (i = 0; i < revlist_args->nr; i++)
 		strvec_push(&fastexport->args, revlist_args->items[i].string);
 
+	strvec_push(&fastexport->args, "--");
+
 	fastexport->git_cmd = 1;
 	return start_command(fastexport);
 }

From 0a8e3f565aec468d60fe229206e28f9d3bdd2469 Mon Sep 17 00:00:00 2001
From: Sverre Rabbelier <srabbelier@gmail.com>
Date: Sun, 24 Jul 2011 00:06:00 +0200
Subject: [PATCH 022/259] remote-helper: check helper status after
 import/export

Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Sverre Rabbelier <srabbelier@gmail.com>
---
 t/t5801-remote-helpers.sh |  2 +-
 transport-helper.c        | 15 +++++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/t/t5801-remote-helpers.sh b/t/t5801-remote-helpers.sh
index 20f43f7b7d3e21..0ba5d0036552c3 100755
--- a/t/t5801-remote-helpers.sh
+++ b/t/t5801-remote-helpers.sh
@@ -262,7 +262,7 @@ test_expect_success 'push update refs failure' '
 	echo "update fail" >>file &&
 	git commit -a -m "update fail" &&
 	git rev-parse --verify testgit/origin/heads/update >expect &&
-	test_expect_code 1 env GIT_REMOTE_TESTGIT_FAILURE="non-fast forward" \
+	test_must_fail env GIT_REMOTE_TESTGIT_FAILURE="non-fast forward" \
 		git push origin update &&
 	git rev-parse --verify testgit/origin/heads/update >actual &&
 	test_cmp expect actual
diff --git a/transport-helper.c b/transport-helper.c
index dbff8362a6123c..8bc913c8770288 100644
--- a/transport-helper.c
+++ b/transport-helper.c
@@ -494,6 +494,19 @@ static int get_exporter(struct transport *transport,
 	return start_command(fastexport);
 }
 
+static void check_helper_status(struct helper_data *data)
+{
+	int pid, status;
+
+	pid = waitpid(data->helper->pid, &status, WNOHANG);
+	if (pid < 0)
+		die("Could not retrieve status of remote helper '%s'",
+		    data->name);
+	if (pid > 0 && WIFEXITED(status))
+		die("Remote helper '%s' died with %d",
+		    data->name, WEXITSTATUS(status));
+}
+
 static int fetch_with_import(struct transport *transport,
 			     int nr_heads, struct ref **to_fetch)
 {
@@ -530,6 +543,7 @@ static int fetch_with_import(struct transport *transport,
 
 	if (finish_command(&fastimport))
 		die(_("error while running fast-import"));
+	check_helper_status(data);
 
 	/*
 	 * The fast-import stream of a remote helper that advertises
@@ -1142,6 +1156,7 @@ static int push_refs_with_export(struct transport *transport,
 
 	if (finish_command(&exporter))
 		die(_("error while running fast-export"));
+	check_helper_status(data);
 	if (push_update_refs_status(data, remote_refs, flags))
 		return 1;
 

From 17bba8e61f2b21653211b37a63aa5713f4b327c1 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 18 Apr 2017 12:09:08 +0200
Subject: [PATCH 023/259] mingw: demonstrate a problem with certain absolute
 paths

On Windows, there are several categories of absolute paths. One such
category starts with a backslash and is implicitly relative to the
drive associated with the current working directory. Example:

	c:
	git clone https://github.com/git-for-windows/git \G4W

should clone into C:\G4W.

There is currently a problem with that, in that mingw_mktemp() does not
expect the _wmktemp() function to prefix the absolute path with the
drive prefix, and as a consequence, the resulting path does not fit into
the originally-passed string buffer. The symptom is a "Result too large"
error.

Reported by Juan Carlos Arevalo Baeza.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t5580-unc-paths.sh | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/t/t5580-unc-paths.sh b/t/t5580-unc-paths.sh
index d7537a162b21fe..dc0788cdbb1552 100755
--- a/t/t5580-unc-paths.sh
+++ b/t/t5580-unc-paths.sh
@@ -21,14 +21,11 @@ fi
 UNCPATH="$(winpwd)"
 case "$UNCPATH" in
 [A-Z]:*)
+	WITHOUTDRIVE="${UNCPATH#?:}"
 	# Use administrative share e.g. \\localhost\C$\git-sdk-64\usr\src\git
 	# (we use forward slashes here because MSYS2 and Git accept them, and
 	# they are easier on the eyes)
-	UNCPATH="//localhost/${UNCPATH%%:*}\$/${UNCPATH#?:}"
-	test -d "$UNCPATH" || {
-		skip_all='could not access administrative share; skipping'
-		test_done
-	}
+	UNCPATH="//localhost/${UNCPATH%%:*}\$$WITHOUTDRIVE"
 	;;
 *)
 	skip_all='skipping UNC path tests, cannot determine current path as UNC'
@@ -36,6 +33,18 @@ case "$UNCPATH" in
 	;;
 esac
 
+test_expect_failure 'clone into absolute path lacking a drive prefix' '
+	USINGBACKSLASHES="$(echo "$WITHOUTDRIVE"/without-drive-prefix |
+		tr / \\\\)" &&
+	git clone . "$USINGBACKSLASHES" &&
+	test -f without-drive-prefix/.git/HEAD
+'
+
+test -d "$UNCPATH" || {
+	skip_all='could not access administrative share; skipping'
+	test_done
+}
+
 test_expect_success setup '
 	test_commit initial
 '

From d80622152ab20c31c51b3453b78c648f4c24c8c3 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 7 Dec 2018 13:39:30 +0100
Subject: [PATCH 024/259] clean: do not traverse mount points

It seems to be not exactly rare on Windows to install NTFS junction
points (the equivalent of "bind mounts" on Linux/Unix) in worktrees,
e.g. to map some development tools into a subdirectory.

In such a scenario, it is pretty horrible if `git clean -dfx` traverses
into the mapped directory and starts to "clean up".

Let's just not do that. Let's make sure before we traverse into a
directory that it is not a mount point (or junction).

This addresses https://github.com/git-for-windows/git/issues/607

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 builtin/clean.c   | 14 ++++++++++++++
 compat/mingw.c    | 22 ++++++++++++++++++++++
 compat/mingw.h    |  3 +++
 git-compat-util.h |  4 ++++
 path.c            | 39 +++++++++++++++++++++++++++++++++++++++
 path.h            |  1 +
 t/t7300-clean.sh  |  9 +++++++++
 7 files changed, 92 insertions(+)

diff --git a/builtin/clean.c b/builtin/clean.c
index ded5a91534c494..e700df6ca66acf 100644
--- a/builtin/clean.c
+++ b/builtin/clean.c
@@ -38,6 +38,8 @@ static const char *msg_remove = N_("Removing %s\n");
 static const char *msg_would_remove = N_("Would remove %s\n");
 static const char *msg_skip_git_dir = N_("Skipping repository %s\n");
 static const char *msg_would_skip_git_dir = N_("Would skip repository %s\n");
+static const char *msg_skip_mount_point = N_("Skipping mount point %s\n");
+static const char *msg_would_skip_mount_point = N_("Would skip mount point %s\n");
 static const char *msg_warn_remove_failed = N_("failed to remove %s");
 static const char *msg_warn_lstat_failed = N_("could not lstat %s\n");
 static const char *msg_skip_cwd = N_("Refusing to remove current working directory\n");
@@ -182,6 +184,18 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 		goto out;
 	}
 
+	if (is_mount_point(path)) {
+		if (!quiet) {
+			quote_path(path->buf, prefix, &quoted, 0);
+			printf(dry_run ?
+			       _(msg_would_skip_mount_point) :
+			       _(msg_skip_mount_point), quoted.buf);
+		}
+		*dir_gone = 0;
+
+		goto out;
+	}
+
 	dir = opendir(path->buf);
 	if (!dir) {
 		/* an empty dir could be removed even if it is unreadble */
diff --git a/compat/mingw.c b/compat/mingw.c
index 29d3f09768c29a..b89d7660ed3381 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2533,6 +2533,28 @@ pid_t waitpid(pid_t pid, int *status, int options)
 	return -1;
 }
 
+int mingw_is_mount_point(struct strbuf *path)
+{
+	WIN32_FIND_DATAW findbuf = { 0 };
+	HANDLE handle;
+	wchar_t wfilename[MAX_PATH];
+	int wlen = xutftowcs_path(wfilename, path->buf);
+	if (wlen < 0)
+		die(_("could not get long path for '%s'"), path->buf);
+
+	/* remove trailing slash, if any */
+	if (wlen > 0 && wfilename[wlen - 1] == L'/')
+		wfilename[--wlen] = L'\0';
+
+	handle = FindFirstFileW(wfilename, &findbuf);
+	if (handle == INVALID_HANDLE_VALUE)
+		return 0;
+	FindClose(handle);
+
+	return (findbuf.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) &&
+		(findbuf.dwReserved0 == IO_REPARSE_TAG_MOUNT_POINT);
+}
+
 int xutftowcsn(wchar_t *wcs, const char *utfs, size_t wcslen, int utflen)
 {
 	int upos = 0, wpos = 0;
diff --git a/compat/mingw.h b/compat/mingw.h
index 27b61284f46be6..a1075cd032d294 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -454,6 +454,9 @@ static inline void convert_slashes(char *path)
 		if (*path == '\\')
 			*path = '/';
 }
+struct strbuf;
+int mingw_is_mount_point(struct strbuf *path);
+#define is_mount_point mingw_is_mount_point
 #define PATH_SEP ';'
 char *mingw_query_user_email(void);
 #define query_user_email mingw_query_user_email
diff --git a/git-compat-util.h b/git-compat-util.h
index 71b4d23f0386b2..a61ad81de31cb2 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -603,6 +603,10 @@ static inline int git_has_dir_sep(const char *path)
 #define has_dir_sep(path) git_has_dir_sep(path)
 #endif
 
+#ifndef is_mount_point
+#define is_mount_point is_mount_point_via_stat
+#endif
+
 #ifndef query_user_email
 #define query_user_email() NULL
 #endif
diff --git a/path.c b/path.c
index 19f7684f3876bd..53b713a094710c 100644
--- a/path.c
+++ b/path.c
@@ -1267,6 +1267,45 @@ char *strip_path_suffix(const char *path, const char *suffix)
 	return offset == -1 ? NULL : xstrndup(path, offset);
 }
 
+int is_mount_point_via_stat(struct strbuf *path)
+{
+	size_t len = path->len;
+	unsigned int current_dev;
+	struct stat st;
+
+	if (!strcmp("/", path->buf))
+		return 1;
+
+	strbuf_addstr(path, "/.");
+	if (lstat(path->buf, &st)) {
+		/*
+		 * If we cannot access the current directory, we cannot say
+		 * that it is a bind mount.
+		 */
+		strbuf_setlen(path, len);
+		return 0;
+	}
+	current_dev = st.st_dev;
+
+	/* Now look at the parent directory */
+	strbuf_addch(path, '.');
+	if (lstat(path->buf, &st)) {
+		/*
+		 * If we cannot access the parent directory, we cannot say
+		 * that it is a bind mount.
+		 */
+		strbuf_setlen(path, len);
+		return 0;
+	}
+	strbuf_setlen(path, len);
+
+	/*
+	 * If the device ID differs between current and parent directory,
+	 * then it is a bind mount.
+	 */
+	return current_dev != st.st_dev;
+}
+
 int daemon_avoid_alias(const char *p)
 {
 	int sl, ndot;
diff --git a/path.h b/path.h
index a6f0b70692a5c0..e96df1f640d649 100644
--- a/path.h
+++ b/path.h
@@ -199,6 +199,7 @@ int normalize_path_copy(char *dst, const char *src);
 int strbuf_normalize_path(struct strbuf *src);
 int longest_ancestor_length(const char *path, struct string_list *prefixes);
 char *strip_path_suffix(const char *path, const char *suffix);
+int is_mount_point_via_stat(struct strbuf *path);
 int daemon_avoid_alias(const char *path);
 
 /*
diff --git a/t/t7300-clean.sh b/t/t7300-clean.sh
index 0aae0dee67078b..ad9336489c234c 100755
--- a/t/t7300-clean.sh
+++ b/t/t7300-clean.sh
@@ -801,4 +801,13 @@ test_expect_success 'traverse into directories that may have ignored entries' '
 	)
 '
 
+test_expect_success MINGW 'clean does not traverse mount points' '
+	mkdir target &&
+	>target/dont-clean-me &&
+	git init with-mountpoint &&
+	cmd //c "mklink /j with-mountpoint\\mountpoint target" &&
+	git -C with-mountpoint clean -dfx &&
+	test_path_is_file target/dont-clean-me
+'
+
 test_done

From e6653f98ad33e48ab8ddd59aa5a553732f8b8a7a Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 9 Apr 2012 13:04:35 -0500
Subject: [PATCH 025/259] Always auto-gc after calling a fast-import transport

After importing anything with fast-import, we should always let the
garbage collector do its job, since the objects are written to disk
inefficiently.

This brings down an initial import of http://selenic.com/hg from about
230 megabytes to about 14.

In the future, we may want to make this configurable on a per-remote
basis, or maybe teach fast-import about it in the first place.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 transport-helper.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/transport-helper.c b/transport-helper.c
index 8bc913c8770288..d4b09c1e84d14a 100644
--- a/transport-helper.c
+++ b/transport-helper.c
@@ -22,6 +22,8 @@
 #include "packfile.h"
 
 static int debug;
+/* TODO: put somewhere sensible, e.g. git_transport_options? */
+static int auto_gc = 1;
 
 struct helper_data {
 	char *name;
@@ -577,6 +579,13 @@ static int fetch_with_import(struct transport *transport,
 		}
 	}
 	strbuf_release(&buf);
+	if (auto_gc) {
+		struct child_process cmd = CHILD_PROCESS_INIT;
+
+		cmd.git_cmd = 1;
+		strvec_pushl(&cmd.args, "gc", "--auto", "--quiet", NULL);
+		run_command(&cmd);
+	}
 	return 0;
 }
 

From 9ff3a3dec254ea7081acee49c99d90fd47d03a92 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 18 Apr 2017 12:38:30 +0200
Subject: [PATCH 026/259] mingw: allow absolute paths without drive prefix

When specifying an absolute path without a drive prefix, we convert that
path internally. Let's make sure that we handle that case properly, too
;-)

This fixes the command

	git clone https://github.com/git-for-windows/git \G4W

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c       | 10 +++++++++-
 t/t5580-unc-paths.sh |  2 +-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 29d3f09768c29a..6d5dc618808384 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1071,11 +1071,19 @@ unsigned int sleep (unsigned int seconds)
 char *mingw_mktemp(char *template)
 {
 	wchar_t wtemplate[MAX_PATH];
+	int offset = 0;
+
 	if (xutftowcs_path(wtemplate, template) < 0)
 		return NULL;
+
+	if (is_dir_sep(template[0]) && !is_dir_sep(template[1]) &&
+	    iswalpha(wtemplate[0]) && wtemplate[1] == L':') {
+		/* We have an absolute path missing the drive prefix */
+		offset = 2;
+	}
 	if (!_wmktemp(wtemplate))
 		return NULL;
-	if (xwcstoutf(template, wtemplate, strlen(template) + 1) < 0)
+	if (xwcstoutf(template, wtemplate + offset, strlen(template) + 1) < 0)
 		return NULL;
 	return template;
 }
diff --git a/t/t5580-unc-paths.sh b/t/t5580-unc-paths.sh
index dc0788cdbb1552..a513dede7e9e88 100755
--- a/t/t5580-unc-paths.sh
+++ b/t/t5580-unc-paths.sh
@@ -33,7 +33,7 @@ case "$UNCPATH" in
 	;;
 esac
 
-test_expect_failure 'clone into absolute path lacking a drive prefix' '
+test_expect_success 'clone into absolute path lacking a drive prefix' '
 	USINGBACKSLASHES="$(echo "$WITHOUTDRIVE"/without-drive-prefix |
 		tr / \\\\)" &&
 	git clone . "$USINGBACKSLASHES" &&

From 8bb6c1e73628492e3aa2d68c3ad8703bb5cce5ee Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 11 Dec 2018 12:55:26 +0100
Subject: [PATCH 027/259] clean: remove mount points when possible

Windows' equivalent to "bind mounts", NTFS junction points, can be
unlinked without affecting the mount target. This is clearly what users
expect to happen when they call `git clean -dfx` in a worktree that
contains NTFS junction points: the junction should be removed, and the
target directory of said junction should be left alone (unless it is
inside the worktree).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 builtin/clean.c  | 13 +++++++++++++
 compat/mingw.h   |  1 +
 t/t7300-clean.sh |  1 +
 3 files changed, 15 insertions(+)

diff --git a/builtin/clean.c b/builtin/clean.c
index e700df6ca66acf..9b416b42a96dfe 100644
--- a/builtin/clean.c
+++ b/builtin/clean.c
@@ -38,8 +38,10 @@ static const char *msg_remove = N_("Removing %s\n");
 static const char *msg_would_remove = N_("Would remove %s\n");
 static const char *msg_skip_git_dir = N_("Skipping repository %s\n");
 static const char *msg_would_skip_git_dir = N_("Would skip repository %s\n");
+#ifndef CAN_UNLINK_MOUNT_POINTS
 static const char *msg_skip_mount_point = N_("Skipping mount point %s\n");
 static const char *msg_would_skip_mount_point = N_("Would skip mount point %s\n");
+#endif
 static const char *msg_warn_remove_failed = N_("failed to remove %s");
 static const char *msg_warn_lstat_failed = N_("could not lstat %s\n");
 static const char *msg_skip_cwd = N_("Refusing to remove current working directory\n");
@@ -185,6 +187,7 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 	}
 
 	if (is_mount_point(path)) {
+#ifndef CAN_UNLINK_MOUNT_POINTS
 		if (!quiet) {
 			quote_path(path->buf, prefix, &quoted, 0);
 			printf(dry_run ?
@@ -192,6 +195,16 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 			       _(msg_skip_mount_point), quoted.buf);
 		}
 		*dir_gone = 0;
+#else
+		if (!dry_run && unlink(path->buf)) {
+			int saved_errno = errno;
+			quote_path(path->buf, prefix, &quoted, 0);
+			errno = saved_errno;
+			warning_errno(_(msg_warn_remove_failed), quoted.buf);
+			*dir_gone = 0;
+			ret = -1;
+		}
+#endif
 
 		goto out;
 	}
diff --git a/compat/mingw.h b/compat/mingw.h
index a1075cd032d294..344586d1c28b7e 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -457,6 +457,7 @@ static inline void convert_slashes(char *path)
 struct strbuf;
 int mingw_is_mount_point(struct strbuf *path);
 #define is_mount_point mingw_is_mount_point
+#define CAN_UNLINK_MOUNT_POINTS 1
 #define PATH_SEP ';'
 char *mingw_query_user_email(void);
 #define query_user_email mingw_query_user_email
diff --git a/t/t7300-clean.sh b/t/t7300-clean.sh
index ad9336489c234c..63e32961709e54 100755
--- a/t/t7300-clean.sh
+++ b/t/t7300-clean.sh
@@ -807,6 +807,7 @@ test_expect_success MINGW 'clean does not traverse mount points' '
 	git init with-mountpoint &&
 	cmd //c "mklink /j with-mountpoint\\mountpoint target" &&
 	git -C with-mountpoint clean -dfx &&
+	test_path_is_missing with-mountpoint/mountpoint &&
 	test_path_is_file target/dont-clean-me
 '
 

From 56860291dbaa6efa57ff163846c68fba67afc1b2 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 16 Feb 2015 14:06:59 +0100
Subject: [PATCH 028/259] mingw: include the Python parts in the build

While Git for Windows does not _ship_ Python (in order to save on
bandwidth), MSYS2 provides very fine Python interpreters that users can
easily take advantage of, by using Git for Windows within its SDK.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 config.mak.uname | 1 +
 1 file changed, 1 insertion(+)

diff --git a/config.mak.uname b/config.mak.uname
index bbf7744ddd5d0f..d59f01a562ed36 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -739,6 +739,7 @@ ifeq ($(uname_S),MINGW)
 	USE_GETTEXT_SCHEME = fallthrough
 	USE_LIBPCRE = YesPlease
 	USE_NED_ALLOCATOR = YesPlease
+	NO_PYTHON =
         ifeq (/mingw64,$(subst 32,64,$(prefix)))
 		# Move system config into top-level /etc/
 		ETC_GITCONFIG = ../etc/gitconfig

From 672e4f23282cd9c6e599a3a3f2584c879ce19881 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sun, 20 Oct 2019 22:08:58 +0200
Subject: [PATCH 029/259] win32/pthread: avoid name clashes with winpthread

The mingw-w64 GCC seems to link implicitly to libwinpthread, which does
implement a pthread emulation (that is more complete than Git's). Let's
keep preferring Git's.

To avoid linker errors where it thinks that the `pthread_self` and the
`pthread_create` symbols are defined twice, let's give our version a
`win32_` prefix, just like we already do for `pthread_join()`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/win32/pthread.c | 6 +++---
 compat/win32/pthread.h | 8 +++++---
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/compat/win32/pthread.c b/compat/win32/pthread.c
index 85f8f7920ce48d..2f35b603248856 100644
--- a/compat/win32/pthread.c
+++ b/compat/win32/pthread.c
@@ -21,8 +21,8 @@ static unsigned __stdcall win32_start_routine(void *arg)
 	return 0;
 }
 
-int pthread_create(pthread_t *thread, const void *unused,
-		   void *(*start_routine)(void *), void *arg)
+int win32_pthread_create(pthread_t *thread, const void *unused,
+			 void *(*start_routine)(void *), void *arg)
 {
 	thread->arg = arg;
 	thread->start_routine = start_routine;
@@ -53,7 +53,7 @@ int win32_pthread_join(pthread_t *thread, void **value_ptr)
 	}
 }
 
-pthread_t pthread_self(void)
+pthread_t win32_pthread_self(void)
 {
 	pthread_t t = { NULL };
 	t.tid = GetCurrentThreadId();
diff --git a/compat/win32/pthread.h b/compat/win32/pthread.h
index cc3221cb2c8a84..d0061ecf33c190 100644
--- a/compat/win32/pthread.h
+++ b/compat/win32/pthread.h
@@ -50,8 +50,9 @@ typedef struct {
 	DWORD tid;
 } pthread_t;
 
-int pthread_create(pthread_t *thread, const void *unused,
-		   void *(*start_routine)(void*), void *arg);
+int win32_pthread_create(pthread_t *thread, const void *unused,
+			 void *(*start_routine)(void*), void *arg);
+#define pthread_create win32_pthread_create
 
 /*
  * To avoid the need of copying a struct, we use small macro wrapper to pass
@@ -62,7 +63,8 @@ int pthread_create(pthread_t *thread, const void *unused,
 int win32_pthread_join(pthread_t *thread, void **value_ptr);
 
 #define pthread_equal(t1, t2) ((t1).tid == (t2).tid)
-pthread_t pthread_self(void);
+pthread_t win32_pthread_self(void);
+#define pthread_self win32_pthread_self
 
 static inline void NORETURN pthread_exit(void *ret)
 {

From 09876ddc7d2b36baf6e838b3a4478244996f4145 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 12 Aug 2022 12:44:15 +0200
Subject: [PATCH 030/259] git-compat-util: avoid redeclaring _DEFAULT_SOURCE

We are about to vendor in `mimalloc`'s source code which we will want to
include `git-compat-util.h` after defining that constant.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 git-compat-util.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/git-compat-util.h b/git-compat-util.h
index 71b4d23f0386b2..468d40498fd35a 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -191,7 +191,9 @@ struct strbuf;
 #define _ALL_SOURCE 1
 #define _GNU_SOURCE 1
 #define _BSD_SOURCE 1
+#ifndef _DEFAULT_SOURCE
 #define _DEFAULT_SOURCE 1
+#endif
 #define _NETBSD_SOURCE 1
 #define _SGI_SOURCE 1
 

From d68cf6d4dbfcec4fd15d0be9757e5479b34a7687 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 24 Jun 2019 21:31:30 +0200
Subject: [PATCH 031/259] Import the source code of mimalloc v2.1.2

This commit imports mimalloc's source code as per v2.1.2, fetched from
the tag at https://github.com/microsoft/mimalloc.

The .c files are from the src/ subdirectory, and the .h files from the
include/ and include/mimalloc/ subdirectories. We will subsequently
modify the source code to accommodate building within Git's context.

Since we plan on using the `mi_*()` family of functions, we skip the
C++-specific source code, some POSIX compliant functions to interact
with mimalloc, and the code that wants to support auto-magic overriding
of the `malloc()` function (mimalloc-new-delete.h, alloc-posix.c,
mimalloc-override.h, alloc-override.c, alloc-override-osx.c,
alloc-override-win.c and static.c).

To appease the `check-whitespace` job of Git's Continuous Integration,
this commit was washed one time via `git rebase --whitespace=fix`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 Makefile                            |    1 +
 compat/mimalloc/LICENSE             |   21 +
 compat/mimalloc/alloc-aligned.c     |  298 +++++
 compat/mimalloc/alloc.c             | 1060 ++++++++++++++++++
 compat/mimalloc/arena.c             |  935 ++++++++++++++++
 compat/mimalloc/bitmap.c            |  432 +++++++
 compat/mimalloc/bitmap.h            |  115 ++
 compat/mimalloc/heap.c              |  626 +++++++++++
 compat/mimalloc/init.c              |  709 ++++++++++++
 compat/mimalloc/mimalloc.h          |  565 ++++++++++
 compat/mimalloc/mimalloc/atomic.h   |  385 +++++++
 compat/mimalloc/mimalloc/internal.h |  979 ++++++++++++++++
 compat/mimalloc/mimalloc/prim.h     |  323 ++++++
 compat/mimalloc/mimalloc/track.h    |  147 +++
 compat/mimalloc/mimalloc/types.h    |  670 +++++++++++
 compat/mimalloc/options.c           |  571 ++++++++++
 compat/mimalloc/os.c                |  689 ++++++++++++
 compat/mimalloc/page-queue.c        |  332 ++++++
 compat/mimalloc/page.c              |  939 ++++++++++++++++
 compat/mimalloc/prim/windows/prim.c |  622 +++++++++++
 compat/mimalloc/random.c            |  254 +++++
 compat/mimalloc/segment-cache.c     |    0
 compat/mimalloc/segment-map.c       |  153 +++
 compat/mimalloc/segment.c           | 1617 +++++++++++++++++++++++++++
 compat/mimalloc/stats.c             |  467 ++++++++
 25 files changed, 12910 insertions(+)
 create mode 100644 compat/mimalloc/LICENSE
 create mode 100644 compat/mimalloc/alloc-aligned.c
 create mode 100644 compat/mimalloc/alloc.c
 create mode 100644 compat/mimalloc/arena.c
 create mode 100644 compat/mimalloc/bitmap.c
 create mode 100644 compat/mimalloc/bitmap.h
 create mode 100644 compat/mimalloc/heap.c
 create mode 100644 compat/mimalloc/init.c
 create mode 100644 compat/mimalloc/mimalloc.h
 create mode 100644 compat/mimalloc/mimalloc/atomic.h
 create mode 100644 compat/mimalloc/mimalloc/internal.h
 create mode 100644 compat/mimalloc/mimalloc/prim.h
 create mode 100644 compat/mimalloc/mimalloc/track.h
 create mode 100644 compat/mimalloc/mimalloc/types.h
 create mode 100644 compat/mimalloc/options.c
 create mode 100644 compat/mimalloc/os.c
 create mode 100644 compat/mimalloc/page-queue.c
 create mode 100644 compat/mimalloc/page.c
 create mode 100644 compat/mimalloc/prim/windows/prim.c
 create mode 100644 compat/mimalloc/random.c
 create mode 100644 compat/mimalloc/segment-cache.c
 create mode 100644 compat/mimalloc/segment-map.c
 create mode 100644 compat/mimalloc/segment.c
 create mode 100644 compat/mimalloc/stats.c

diff --git a/Makefile b/Makefile
index d6479092a0b8df..db48c72620c78d 100644
--- a/Makefile
+++ b/Makefile
@@ -1325,6 +1325,7 @@ BUILTIN_OBJS += builtin/write-tree.o
 # upstream unnecessarily (making merging in future changes easier).
 THIRD_PARTY_SOURCES += compat/inet_ntop.c
 THIRD_PARTY_SOURCES += compat/inet_pton.c
+THIRD_PARTY_SOURCES += compat/mimalloc/%
 THIRD_PARTY_SOURCES += compat/nedmalloc/%
 THIRD_PARTY_SOURCES += compat/obstack.%
 THIRD_PARTY_SOURCES += compat/poll/%
diff --git a/compat/mimalloc/LICENSE b/compat/mimalloc/LICENSE
new file mode 100644
index 00000000000000..670b668a0c928e
--- /dev/null
+++ b/compat/mimalloc/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2018-2021 Microsoft Corporation, Daan Leijen
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/compat/mimalloc/alloc-aligned.c b/compat/mimalloc/alloc-aligned.c
new file mode 100644
index 00000000000000..e975af5f7c2ad4
--- /dev/null
+++ b/compat/mimalloc/alloc-aligned.c
@@ -0,0 +1,298 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2021, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "mimalloc/prim.h"  // mi_prim_get_default_heap
+
+#include <string.h>     // memset
+
+// ------------------------------------------------------
+// Aligned Allocation
+// ------------------------------------------------------
+
+// Fallback primitive aligned allocation -- split out for better codegen
+static mi_decl_noinline void* mi_heap_malloc_zero_aligned_at_fallback(mi_heap_t* const heap, const size_t size, const size_t alignment, const size_t offset, const bool zero) mi_attr_noexcept
+{
+  mi_assert_internal(size <= PTRDIFF_MAX);
+  mi_assert_internal(alignment != 0 && _mi_is_power_of_two(alignment));
+
+  const uintptr_t align_mask = alignment - 1;  // for any x, `(x & align_mask) == (x % alignment)`
+  const size_t padsize = size + MI_PADDING_SIZE;
+
+  // use regular allocation if it is guaranteed to fit the alignment constraints
+  if (offset==0 && alignment<=padsize && padsize<=MI_MAX_ALIGN_GUARANTEE && (padsize&align_mask)==0) {
+    void* p = _mi_heap_malloc_zero(heap, size, zero);
+    mi_assert_internal(p == NULL || ((uintptr_t)p % alignment) == 0);
+    return p;
+  }
+
+  void* p;
+  size_t oversize;
+  if mi_unlikely(alignment > MI_ALIGNMENT_MAX) {
+    // use OS allocation for very large alignment and allocate inside a huge page (dedicated segment with 1 page)
+    // This can support alignments >= MI_SEGMENT_SIZE by ensuring the object can be aligned at a point in the
+    // first (and single) page such that the segment info is `MI_SEGMENT_SIZE` bytes before it (so it can be found by aligning the pointer down)
+    if mi_unlikely(offset != 0) {
+      // todo: cannot support offset alignment for very large alignments yet
+      #if MI_DEBUG > 0
+      _mi_error_message(EOVERFLOW, "aligned allocation with a very large alignment cannot be used with an alignment offset (size %zu, alignment %zu, offset %zu)\n", size, alignment, offset);
+      #endif
+      return NULL;
+    }
+    oversize = (size <= MI_SMALL_SIZE_MAX ? MI_SMALL_SIZE_MAX + 1 /* ensure we use generic malloc path */ : size);
+    p = _mi_heap_malloc_zero_ex(heap, oversize, false, alignment); // the page block size should be large enough to align in the single huge page block
+    // zero afterwards as only the area from the aligned_p may be committed!
+    if (p == NULL) return NULL;
+  }
+  else {
+    // otherwise over-allocate
+    oversize = size + alignment - 1;
+    p = _mi_heap_malloc_zero(heap, oversize, zero);
+    if (p == NULL) return NULL;
+  }
+
+  // .. and align within the allocation
+  const uintptr_t poffset = ((uintptr_t)p + offset) & align_mask;
+  const uintptr_t adjust  = (poffset == 0 ? 0 : alignment - poffset);
+  mi_assert_internal(adjust < alignment);
+  void* aligned_p = (void*)((uintptr_t)p + adjust);
+  if (aligned_p != p) {
+    mi_page_t* page = _mi_ptr_page(p);
+    mi_page_set_has_aligned(page, true);
+    _mi_padding_shrink(page, (mi_block_t*)p, adjust + size);
+  }
+  // todo: expand padding if overallocated ?
+
+  mi_assert_internal(mi_page_usable_block_size(_mi_ptr_page(p)) >= adjust + size);
+  mi_assert_internal(p == _mi_page_ptr_unalign(_mi_ptr_segment(aligned_p), _mi_ptr_page(aligned_p), aligned_p));
+  mi_assert_internal(((uintptr_t)aligned_p + offset) % alignment == 0);
+  mi_assert_internal(mi_usable_size(aligned_p)>=size);
+  mi_assert_internal(mi_usable_size(p) == mi_usable_size(aligned_p)+adjust);
+
+  // now zero the block if needed
+  if (alignment > MI_ALIGNMENT_MAX) {
+    // for the tracker, on huge aligned allocations only from the start of the large block is defined
+    mi_track_mem_undefined(aligned_p, size);
+    if (zero) {
+      _mi_memzero_aligned(aligned_p, mi_usable_size(aligned_p));
+    }
+  }
+
+  if (p != aligned_p) {
+    mi_track_align(p,aligned_p,adjust,mi_usable_size(aligned_p));
+  }
+  return aligned_p;
+}
+
+// Primitive aligned allocation
+static void* mi_heap_malloc_zero_aligned_at(mi_heap_t* const heap, const size_t size, const size_t alignment, const size_t offset, const bool zero) mi_attr_noexcept
+{
+  // note: we don't require `size > offset`, we just guarantee that the address at offset is aligned regardless of the allocated size.
+  if mi_unlikely(alignment == 0 || !_mi_is_power_of_two(alignment)) { // require power-of-two (see <https://en.cppreference.com/w/c/memory/aligned_alloc>)
+    #if MI_DEBUG > 0
+    _mi_error_message(EOVERFLOW, "aligned allocation requires the alignment to be a power-of-two (size %zu, alignment %zu)\n", size, alignment);
+    #endif
+    return NULL;
+  }
+
+  if mi_unlikely(size > PTRDIFF_MAX) {          // we don't allocate more than PTRDIFF_MAX (see <https://sourceware.org/ml/libc-announce/2019/msg00001.html>)
+    #if MI_DEBUG > 0
+    _mi_error_message(EOVERFLOW, "aligned allocation request is too large (size %zu, alignment %zu)\n", size, alignment);
+    #endif
+    return NULL;
+  }
+  const uintptr_t align_mask = alignment-1;       // for any x, `(x & align_mask) == (x % alignment)`
+  const size_t padsize = size + MI_PADDING_SIZE;  // note: cannot overflow due to earlier size > PTRDIFF_MAX check
+
+  // try first if there happens to be a small block available with just the right alignment
+  if mi_likely(padsize <= MI_SMALL_SIZE_MAX && alignment <= padsize) {
+    mi_page_t* page = _mi_heap_get_free_small_page(heap, padsize);
+    const bool is_aligned = (((uintptr_t)page->free+offset) & align_mask)==0;
+    if mi_likely(page->free != NULL && is_aligned)
+    {
+      #if MI_STAT>1
+      mi_heap_stat_increase(heap, malloc, size);
+      #endif
+      void* p = _mi_page_malloc(heap, page, padsize, zero); // TODO: inline _mi_page_malloc
+      mi_assert_internal(p != NULL);
+      mi_assert_internal(((uintptr_t)p + offset) % alignment == 0);
+      mi_track_malloc(p,size,zero);
+      return p;
+    }
+  }
+  // fallback
+  return mi_heap_malloc_zero_aligned_at_fallback(heap, size, alignment, offset, zero);
+}
+
+
+// ------------------------------------------------------
+// Optimized mi_heap_malloc_aligned / mi_malloc_aligned
+// ------------------------------------------------------
+
+mi_decl_nodiscard mi_decl_restrict void* mi_heap_malloc_aligned_at(mi_heap_t* heap, size_t size, size_t alignment, size_t offset) mi_attr_noexcept {
+  return mi_heap_malloc_zero_aligned_at(heap, size, alignment, offset, false);
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_heap_malloc_aligned(mi_heap_t* heap, size_t size, size_t alignment) mi_attr_noexcept {
+  if mi_unlikely(alignment == 0 || !_mi_is_power_of_two(alignment)) return NULL;
+  #if !MI_PADDING
+  // without padding, any small sized allocation is naturally aligned (see also `_mi_segment_page_start`)
+  if mi_likely(_mi_is_power_of_two(size) && size >= alignment && size <= MI_SMALL_SIZE_MAX)
+  #else
+  // with padding, we can only guarantee this for fixed alignments
+  if mi_likely((alignment == sizeof(void*) || (alignment == MI_MAX_ALIGN_SIZE && size > (MI_MAX_ALIGN_SIZE/2)))
+		&& size <= MI_SMALL_SIZE_MAX)
+  #endif
+  {
+    // fast path for common alignment and size
+    return mi_heap_malloc_small(heap, size);
+  }
+  else {
+    return mi_heap_malloc_aligned_at(heap, size, alignment, 0);
+  }
+}
+
+// ensure a definition is emitted
+#if defined(__cplusplus)
+static void* _mi_heap_malloc_aligned = (void*)&mi_heap_malloc_aligned;
+#endif
+
+// ------------------------------------------------------
+// Aligned Allocation
+// ------------------------------------------------------
+
+mi_decl_nodiscard mi_decl_restrict void* mi_heap_zalloc_aligned_at(mi_heap_t* heap, size_t size, size_t alignment, size_t offset) mi_attr_noexcept {
+  return mi_heap_malloc_zero_aligned_at(heap, size, alignment, offset, true);
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_heap_zalloc_aligned(mi_heap_t* heap, size_t size, size_t alignment) mi_attr_noexcept {
+  return mi_heap_zalloc_aligned_at(heap, size, alignment, 0);
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_heap_calloc_aligned_at(mi_heap_t* heap, size_t count, size_t size, size_t alignment, size_t offset) mi_attr_noexcept {
+  size_t total;
+  if (mi_count_size_overflow(count, size, &total)) return NULL;
+  return mi_heap_zalloc_aligned_at(heap, total, alignment, offset);
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_heap_calloc_aligned(mi_heap_t* heap, size_t count, size_t size, size_t alignment) mi_attr_noexcept {
+  return mi_heap_calloc_aligned_at(heap,count,size,alignment,0);
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_malloc_aligned_at(size_t size, size_t alignment, size_t offset) mi_attr_noexcept {
+  return mi_heap_malloc_aligned_at(mi_prim_get_default_heap(), size, alignment, offset);
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_malloc_aligned(size_t size, size_t alignment) mi_attr_noexcept {
+  return mi_heap_malloc_aligned(mi_prim_get_default_heap(), size, alignment);
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_zalloc_aligned_at(size_t size, size_t alignment, size_t offset) mi_attr_noexcept {
+  return mi_heap_zalloc_aligned_at(mi_prim_get_default_heap(), size, alignment, offset);
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_zalloc_aligned(size_t size, size_t alignment) mi_attr_noexcept {
+  return mi_heap_zalloc_aligned(mi_prim_get_default_heap(), size, alignment);
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_calloc_aligned_at(size_t count, size_t size, size_t alignment, size_t offset) mi_attr_noexcept {
+  return mi_heap_calloc_aligned_at(mi_prim_get_default_heap(), count, size, alignment, offset);
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_calloc_aligned(size_t count, size_t size, size_t alignment) mi_attr_noexcept {
+  return mi_heap_calloc_aligned(mi_prim_get_default_heap(), count, size, alignment);
+}
+
+
+// ------------------------------------------------------
+// Aligned re-allocation
+// ------------------------------------------------------
+
+static void* mi_heap_realloc_zero_aligned_at(mi_heap_t* heap, void* p, size_t newsize, size_t alignment, size_t offset, bool zero) mi_attr_noexcept {
+  mi_assert(alignment > 0);
+  if (alignment <= sizeof(uintptr_t)) return _mi_heap_realloc_zero(heap,p,newsize,zero);
+  if (p == NULL) return mi_heap_malloc_zero_aligned_at(heap,newsize,alignment,offset,zero);
+  size_t size = mi_usable_size(p);
+  if (newsize <= size && newsize >= (size - (size / 2))
+      && (((uintptr_t)p + offset) % alignment) == 0) {
+    return p;  // reallocation still fits, is aligned and not more than 50% waste
+  }
+  else {
+    // note: we don't zero allocate upfront so we only zero initialize the expanded part
+    void* newp = mi_heap_malloc_aligned_at(heap,newsize,alignment,offset);
+    if (newp != NULL) {
+      if (zero && newsize > size) {
+	// also set last word in the previous allocation to zero to ensure any padding is zero-initialized
+	size_t start = (size >= sizeof(intptr_t) ? size - sizeof(intptr_t) : 0);
+	_mi_memzero((uint8_t*)newp + start, newsize - start);
+      }
+      _mi_memcpy_aligned(newp, p, (newsize > size ? size : newsize));
+      mi_free(p); // only free if successful
+    }
+    return newp;
+  }
+}
+
+static void* mi_heap_realloc_zero_aligned(mi_heap_t* heap, void* p, size_t newsize, size_t alignment, bool zero) mi_attr_noexcept {
+  mi_assert(alignment > 0);
+  if (alignment <= sizeof(uintptr_t)) return _mi_heap_realloc_zero(heap,p,newsize,zero);
+  size_t offset = ((uintptr_t)p % alignment); // use offset of previous allocation (p can be NULL)
+  return mi_heap_realloc_zero_aligned_at(heap,p,newsize,alignment,offset,zero);
+}
+
+mi_decl_nodiscard void* mi_heap_realloc_aligned_at(mi_heap_t* heap, void* p, size_t newsize, size_t alignment, size_t offset) mi_attr_noexcept {
+  return mi_heap_realloc_zero_aligned_at(heap,p,newsize,alignment,offset,false);
+}
+
+mi_decl_nodiscard void* mi_heap_realloc_aligned(mi_heap_t* heap, void* p, size_t newsize, size_t alignment) mi_attr_noexcept {
+  return mi_heap_realloc_zero_aligned(heap,p,newsize,alignment,false);
+}
+
+mi_decl_nodiscard void* mi_heap_rezalloc_aligned_at(mi_heap_t* heap, void* p, size_t newsize, size_t alignment, size_t offset) mi_attr_noexcept {
+  return mi_heap_realloc_zero_aligned_at(heap, p, newsize, alignment, offset, true);
+}
+
+mi_decl_nodiscard void* mi_heap_rezalloc_aligned(mi_heap_t* heap, void* p, size_t newsize, size_t alignment) mi_attr_noexcept {
+  return mi_heap_realloc_zero_aligned(heap, p, newsize, alignment, true);
+}
+
+mi_decl_nodiscard void* mi_heap_recalloc_aligned_at(mi_heap_t* heap, void* p, size_t newcount, size_t size, size_t alignment, size_t offset) mi_attr_noexcept {
+  size_t total;
+  if (mi_count_size_overflow(newcount, size, &total)) return NULL;
+  return mi_heap_rezalloc_aligned_at(heap, p, total, alignment, offset);
+}
+
+mi_decl_nodiscard void* mi_heap_recalloc_aligned(mi_heap_t* heap, void* p, size_t newcount, size_t size, size_t alignment) mi_attr_noexcept {
+  size_t total;
+  if (mi_count_size_overflow(newcount, size, &total)) return NULL;
+  return mi_heap_rezalloc_aligned(heap, p, total, alignment);
+}
+
+mi_decl_nodiscard void* mi_realloc_aligned_at(void* p, size_t newsize, size_t alignment, size_t offset) mi_attr_noexcept {
+  return mi_heap_realloc_aligned_at(mi_prim_get_default_heap(), p, newsize, alignment, offset);
+}
+
+mi_decl_nodiscard void* mi_realloc_aligned(void* p, size_t newsize, size_t alignment) mi_attr_noexcept {
+  return mi_heap_realloc_aligned(mi_prim_get_default_heap(), p, newsize, alignment);
+}
+
+mi_decl_nodiscard void* mi_rezalloc_aligned_at(void* p, size_t newsize, size_t alignment, size_t offset) mi_attr_noexcept {
+  return mi_heap_rezalloc_aligned_at(mi_prim_get_default_heap(), p, newsize, alignment, offset);
+}
+
+mi_decl_nodiscard void* mi_rezalloc_aligned(void* p, size_t newsize, size_t alignment) mi_attr_noexcept {
+  return mi_heap_rezalloc_aligned(mi_prim_get_default_heap(), p, newsize, alignment);
+}
+
+mi_decl_nodiscard void* mi_recalloc_aligned_at(void* p, size_t newcount, size_t size, size_t alignment, size_t offset) mi_attr_noexcept {
+  return mi_heap_recalloc_aligned_at(mi_prim_get_default_heap(), p, newcount, size, alignment, offset);
+}
+
+mi_decl_nodiscard void* mi_recalloc_aligned(void* p, size_t newcount, size_t size, size_t alignment) mi_attr_noexcept {
+  return mi_heap_recalloc_aligned(mi_prim_get_default_heap(), p, newcount, size, alignment);
+}
diff --git a/compat/mimalloc/alloc.c b/compat/mimalloc/alloc.c
new file mode 100644
index 00000000000000..961f6d53d0f2c7
--- /dev/null
+++ b/compat/mimalloc/alloc.c
@@ -0,0 +1,1060 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2022, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+#ifndef _DEFAULT_SOURCE
+#define _DEFAULT_SOURCE   // for realpath() on Linux
+#endif
+
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "mimalloc/atomic.h"
+#include "mimalloc/prim.h"   // _mi_prim_thread_id()
+
+#include <string.h>      // memset, strlen (for mi_strdup)
+#include <stdlib.h>      // malloc, abort
+
+#define MI_IN_ALLOC_C
+#include "alloc-override.c"
+#undef MI_IN_ALLOC_C
+
+// ------------------------------------------------------
+// Allocation
+// ------------------------------------------------------
+
+// Fast allocation in a page: just pop from the free list.
+// Fall back to generic allocation only if the list is empty.
+extern inline void* _mi_page_malloc(mi_heap_t* heap, mi_page_t* page, size_t size, bool zero) mi_attr_noexcept {
+  mi_assert_internal(page->xblock_size==0||mi_page_block_size(page) >= size);
+  mi_block_t* const block = page->free;
+  if mi_unlikely(block == NULL) {
+    return _mi_malloc_generic(heap, size, zero, 0);
+  }
+  mi_assert_internal(block != NULL && _mi_ptr_page(block) == page);
+  // pop from the free list
+  page->used++;
+  page->free = mi_block_next(page, block);
+  mi_assert_internal(page->free == NULL || _mi_ptr_page(page->free) == page);
+  #if MI_DEBUG>3
+  if (page->free_is_zero) {
+    mi_assert_expensive(mi_mem_is_zero(block+1,size - sizeof(*block)));
+  }
+  #endif
+
+  // allow use of the block internally
+  // note: when tracking we need to avoid ever touching the MI_PADDING since
+  // that is tracked by valgrind etc. as non-accessible (through the red-zone, see `mimalloc/track.h`)
+  mi_track_mem_undefined(block, mi_page_usable_block_size(page));
+
+  // zero the block? note: we need to zero the full block size (issue #63)
+  if mi_unlikely(zero) {
+    mi_assert_internal(page->xblock_size != 0); // do not call with zero'ing for huge blocks (see _mi_malloc_generic)
+    mi_assert_internal(page->xblock_size >= MI_PADDING_SIZE);
+    if (page->free_is_zero) {
+      block->next = 0;
+      mi_track_mem_defined(block, page->xblock_size - MI_PADDING_SIZE);
+    }
+    else {
+      _mi_memzero_aligned(block, page->xblock_size - MI_PADDING_SIZE);
+    }
+  }
+
+#if (MI_DEBUG>0) && !MI_TRACK_ENABLED && !MI_TSAN
+  if (!zero && !mi_page_is_huge(page)) {
+    memset(block, MI_DEBUG_UNINIT, mi_page_usable_block_size(page));
+  }
+#elif (MI_SECURE!=0)
+  if (!zero) { block->next = 0; } // don't leak internal data
+#endif
+
+#if (MI_STAT>0)
+  const size_t bsize = mi_page_usable_block_size(page);
+  if (bsize <= MI_MEDIUM_OBJ_SIZE_MAX) {
+    mi_heap_stat_increase(heap, normal, bsize);
+    mi_heap_stat_counter_increase(heap, normal_count, 1);
+#if (MI_STAT>1)
+    const size_t bin = _mi_bin(bsize);
+    mi_heap_stat_increase(heap, normal_bins[bin], 1);
+#endif
+  }
+#endif
+
+#if MI_PADDING // && !MI_TRACK_ENABLED
+  mi_padding_t* const padding = (mi_padding_t*)((uint8_t*)block + mi_page_usable_block_size(page));
+  ptrdiff_t delta = ((uint8_t*)padding - (uint8_t*)block - (size - MI_PADDING_SIZE));
+  #if (MI_DEBUG>=2)
+  mi_assert_internal(delta >= 0 && mi_page_usable_block_size(page) >= (size - MI_PADDING_SIZE + delta));
+  #endif
+  mi_track_mem_defined(padding,sizeof(mi_padding_t));  // note: re-enable since mi_page_usable_block_size may set noaccess
+  padding->canary = (uint32_t)(mi_ptr_encode(page,block,page->keys));
+  padding->delta  = (uint32_t)(delta);
+  #if MI_PADDING_CHECK
+  if (!mi_page_is_huge(page)) {
+    uint8_t* fill = (uint8_t*)padding - delta;
+    const size_t maxpad = (delta > MI_MAX_ALIGN_SIZE ? MI_MAX_ALIGN_SIZE : delta); // set at most N initial padding bytes
+    for (size_t i = 0; i < maxpad; i++) { fill[i] = MI_DEBUG_PADDING; }
+  }
+  #endif
+#endif
+
+  return block;
+}
+
+static inline mi_decl_restrict void* mi_heap_malloc_small_zero(mi_heap_t* heap, size_t size, bool zero) mi_attr_noexcept {
+  mi_assert(heap != NULL);
+  #if MI_DEBUG
+  const uintptr_t tid = _mi_thread_id();
+  mi_assert(heap->thread_id == 0 || heap->thread_id == tid); // heaps are thread local
+  #endif
+  mi_assert(size <= MI_SMALL_SIZE_MAX);
+  #if (MI_PADDING)
+  if (size == 0) { size = sizeof(void*); }
+  #endif
+  mi_page_t* page = _mi_heap_get_free_small_page(heap, size + MI_PADDING_SIZE);
+  void* const p = _mi_page_malloc(heap, page, size + MI_PADDING_SIZE, zero);
+  mi_track_malloc(p,size,zero);
+  #if MI_STAT>1
+  if (p != NULL) {
+    if (!mi_heap_is_initialized(heap)) { heap = mi_prim_get_default_heap(); }
+    mi_heap_stat_increase(heap, malloc, mi_usable_size(p));
+  }
+  #endif
+  #if MI_DEBUG>3
+  if (p != NULL && zero) {
+    mi_assert_expensive(mi_mem_is_zero(p, size));
+  }
+  #endif
+  return p;
+}
+
+// allocate a small block
+mi_decl_nodiscard extern inline mi_decl_restrict void* mi_heap_malloc_small(mi_heap_t* heap, size_t size) mi_attr_noexcept {
+  return mi_heap_malloc_small_zero(heap, size, false);
+}
+
+mi_decl_nodiscard extern inline mi_decl_restrict void* mi_malloc_small(size_t size) mi_attr_noexcept {
+  return mi_heap_malloc_small(mi_prim_get_default_heap(), size);
+}
+
+// The main allocation function
+extern inline void* _mi_heap_malloc_zero_ex(mi_heap_t* heap, size_t size, bool zero, size_t huge_alignment) mi_attr_noexcept {
+  if mi_likely(size <= MI_SMALL_SIZE_MAX) {
+    mi_assert_internal(huge_alignment == 0);
+    return mi_heap_malloc_small_zero(heap, size, zero);
+  }
+  else {
+    mi_assert(heap!=NULL);
+    mi_assert(heap->thread_id == 0 || heap->thread_id == _mi_thread_id());   // heaps are thread local
+    void* const p = _mi_malloc_generic(heap, size + MI_PADDING_SIZE, zero, huge_alignment);  // note: size can overflow but it is detected in malloc_generic
+    mi_track_malloc(p,size,zero);
+    #if MI_STAT>1
+    if (p != NULL) {
+      if (!mi_heap_is_initialized(heap)) { heap = mi_prim_get_default_heap(); }
+      mi_heap_stat_increase(heap, malloc, mi_usable_size(p));
+    }
+    #endif
+    #if MI_DEBUG>3
+    if (p != NULL && zero) {
+      mi_assert_expensive(mi_mem_is_zero(p, size));
+    }
+    #endif
+    return p;
+  }
+}
+
+extern inline void* _mi_heap_malloc_zero(mi_heap_t* heap, size_t size, bool zero) mi_attr_noexcept {
+  return _mi_heap_malloc_zero_ex(heap, size, zero, 0);
+}
+
+mi_decl_nodiscard extern inline mi_decl_restrict void* mi_heap_malloc(mi_heap_t* heap, size_t size) mi_attr_noexcept {
+  return _mi_heap_malloc_zero(heap, size, false);
+}
+
+mi_decl_nodiscard extern inline mi_decl_restrict void* mi_malloc(size_t size) mi_attr_noexcept {
+  return mi_heap_malloc(mi_prim_get_default_heap(), size);
+}
+
+// zero initialized small block
+mi_decl_nodiscard mi_decl_restrict void* mi_zalloc_small(size_t size) mi_attr_noexcept {
+  return mi_heap_malloc_small_zero(mi_prim_get_default_heap(), size, true);
+}
+
+mi_decl_nodiscard extern inline mi_decl_restrict void* mi_heap_zalloc(mi_heap_t* heap, size_t size) mi_attr_noexcept {
+  return _mi_heap_malloc_zero(heap, size, true);
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_zalloc(size_t size) mi_attr_noexcept {
+  return mi_heap_zalloc(mi_prim_get_default_heap(),size);
+}
+
+
+// ------------------------------------------------------
+// Check for double free in secure and debug mode
+// This is somewhat expensive so only enabled for secure mode 4
+// ------------------------------------------------------
+
+#if (MI_ENCODE_FREELIST && (MI_SECURE>=4 || MI_DEBUG!=0))
+// linear check if the free list contains a specific element
+static bool mi_list_contains(const mi_page_t* page, const mi_block_t* list, const mi_block_t* elem) {
+  while (list != NULL) {
+    if (elem==list) return true;
+    list = mi_block_next(page, list);
+  }
+  return false;
+}
+
+static mi_decl_noinline bool mi_check_is_double_freex(const mi_page_t* page, const mi_block_t* block) {
+  // The decoded value is in the same page (or NULL).
+  // Walk the free lists to verify positively if it is already freed
+  if (mi_list_contains(page, page->free, block) ||
+      mi_list_contains(page, page->local_free, block) ||
+      mi_list_contains(page, mi_page_thread_free(page), block))
+  {
+    _mi_error_message(EAGAIN, "double free detected of block %p with size %zu\n", block, mi_page_block_size(page));
+    return true;
+  }
+  return false;
+}
+
+#define mi_track_page(page,access)  { size_t psize; void* pstart = _mi_page_start(_mi_page_segment(page),page,&psize); mi_track_mem_##access( pstart, psize); }
+
+static inline bool mi_check_is_double_free(const mi_page_t* page, const mi_block_t* block) {
+  bool is_double_free = false;
+  mi_block_t* n = mi_block_nextx(page, block, page->keys); // pretend it is freed, and get the decoded first field
+  if (((uintptr_t)n & (MI_INTPTR_SIZE-1))==0 &&  // quick check: aligned pointer?
+      (n==NULL || mi_is_in_same_page(block, n))) // quick check: in same page or NULL?
+  {
+    // Suspicous: decoded value a in block is in the same page (or NULL) -- maybe a double free?
+    // (continue in separate function to improve code generation)
+    is_double_free = mi_check_is_double_freex(page, block);
+  }
+  return is_double_free;
+}
+#else
+static inline bool mi_check_is_double_free(const mi_page_t* page, const mi_block_t* block) {
+  MI_UNUSED(page);
+  MI_UNUSED(block);
+  return false;
+}
+#endif
+
+// ---------------------------------------------------------------------------
+// Check for heap block overflow by setting up padding at the end of the block
+// ---------------------------------------------------------------------------
+
+#if MI_PADDING // && !MI_TRACK_ENABLED
+static bool mi_page_decode_padding(const mi_page_t* page, const mi_block_t* block, size_t* delta, size_t* bsize) {
+  *bsize = mi_page_usable_block_size(page);
+  const mi_padding_t* const padding = (mi_padding_t*)((uint8_t*)block + *bsize);
+  mi_track_mem_defined(padding,sizeof(mi_padding_t));
+  *delta = padding->delta;
+  uint32_t canary = padding->canary;
+  uintptr_t keys[2];
+  keys[0] = page->keys[0];
+  keys[1] = page->keys[1];
+  bool ok = ((uint32_t)mi_ptr_encode(page,block,keys) == canary && *delta <= *bsize);
+  mi_track_mem_noaccess(padding,sizeof(mi_padding_t));
+  return ok;
+}
+
+// Return the exact usable size of a block.
+static size_t mi_page_usable_size_of(const mi_page_t* page, const mi_block_t* block) {
+  size_t bsize;
+  size_t delta;
+  bool ok = mi_page_decode_padding(page, block, &delta, &bsize);
+  mi_assert_internal(ok); mi_assert_internal(delta <= bsize);
+  return (ok ? bsize - delta : 0);
+}
+
+// When a non-thread-local block is freed, it becomes part of the thread delayed free
+// list that is freed later by the owning heap. If the exact usable size is too small to
+// contain the pointer for the delayed list, then shrink the padding (by decreasing delta)
+// so it will later not trigger an overflow error in `mi_free_block`.
+void _mi_padding_shrink(const mi_page_t* page, const mi_block_t* block, const size_t min_size) {
+  size_t bsize;
+  size_t delta;
+  bool ok = mi_page_decode_padding(page, block, &delta, &bsize);
+  mi_assert_internal(ok);
+  if (!ok || (bsize - delta) >= min_size) return;  // usually already enough space
+  mi_assert_internal(bsize >= min_size);
+  if (bsize < min_size) return;  // should never happen
+  size_t new_delta = (bsize - min_size);
+  mi_assert_internal(new_delta < bsize);
+  mi_padding_t* padding = (mi_padding_t*)((uint8_t*)block + bsize);
+  mi_track_mem_defined(padding,sizeof(mi_padding_t));
+  padding->delta = (uint32_t)new_delta;
+  mi_track_mem_noaccess(padding,sizeof(mi_padding_t));
+}
+#else
+static size_t mi_page_usable_size_of(const mi_page_t* page, const mi_block_t* block) {
+  MI_UNUSED(block);
+  return mi_page_usable_block_size(page);
+}
+
+void _mi_padding_shrink(const mi_page_t* page, const mi_block_t* block, const size_t min_size) {
+  MI_UNUSED(page);
+  MI_UNUSED(block);
+  MI_UNUSED(min_size);
+}
+#endif
+
+#if MI_PADDING && MI_PADDING_CHECK
+
+static bool mi_verify_padding(const mi_page_t* page, const mi_block_t* block, size_t* size, size_t* wrong) {
+  size_t bsize;
+  size_t delta;
+  bool ok = mi_page_decode_padding(page, block, &delta, &bsize);
+  *size = *wrong = bsize;
+  if (!ok) return false;
+  mi_assert_internal(bsize >= delta);
+  *size = bsize - delta;
+  if (!mi_page_is_huge(page)) {
+    uint8_t* fill = (uint8_t*)block + bsize - delta;
+    const size_t maxpad = (delta > MI_MAX_ALIGN_SIZE ? MI_MAX_ALIGN_SIZE : delta); // check at most the first N padding bytes
+    mi_track_mem_defined(fill, maxpad);
+    for (size_t i = 0; i < maxpad; i++) {
+      if (fill[i] != MI_DEBUG_PADDING) {
+	*wrong = bsize - delta + i;
+	ok = false;
+	break;
+      }
+    }
+    mi_track_mem_noaccess(fill, maxpad);
+  }
+  return ok;
+}
+
+static void mi_check_padding(const mi_page_t* page, const mi_block_t* block) {
+  size_t size;
+  size_t wrong;
+  if (!mi_verify_padding(page,block,&size,&wrong)) {
+    _mi_error_message(EFAULT, "buffer overflow in heap block %p of size %zu: write after %zu bytes\n", block, size, wrong );
+  }
+}
+
+#else
+
+static void mi_check_padding(const mi_page_t* page, const mi_block_t* block) {
+  MI_UNUSED(page);
+  MI_UNUSED(block);
+}
+
+#endif
+
+// only maintain stats for smaller objects if requested
+#if (MI_STAT>0)
+static void mi_stat_free(const mi_page_t* page, const mi_block_t* block) {
+  #if (MI_STAT < 2)
+  MI_UNUSED(block);
+  #endif
+  mi_heap_t* const heap = mi_heap_get_default();
+  const size_t bsize = mi_page_usable_block_size(page);
+  #if (MI_STAT>1)
+  const size_t usize = mi_page_usable_size_of(page, block);
+  mi_heap_stat_decrease(heap, malloc, usize);
+  #endif
+  if (bsize <= MI_MEDIUM_OBJ_SIZE_MAX) {
+    mi_heap_stat_decrease(heap, normal, bsize);
+    #if (MI_STAT > 1)
+    mi_heap_stat_decrease(heap, normal_bins[_mi_bin(bsize)], 1);
+    #endif
+  }
+  else if (bsize <= MI_LARGE_OBJ_SIZE_MAX) {
+    mi_heap_stat_decrease(heap, large, bsize);
+  }
+  else {
+    mi_heap_stat_decrease(heap, huge, bsize);
+  }
+}
+#else
+static void mi_stat_free(const mi_page_t* page, const mi_block_t* block) {
+  MI_UNUSED(page); MI_UNUSED(block);
+}
+#endif
+
+#if MI_HUGE_PAGE_ABANDON
+#if (MI_STAT>0)
+// maintain stats for huge objects
+static void mi_stat_huge_free(const mi_page_t* page) {
+  mi_heap_t* const heap = mi_heap_get_default();
+  const size_t bsize = mi_page_block_size(page); // to match stats in `page.c:mi_page_huge_alloc`
+  if (bsize <= MI_LARGE_OBJ_SIZE_MAX) {
+    mi_heap_stat_decrease(heap, large, bsize);
+  }
+  else {
+    mi_heap_stat_decrease(heap, huge, bsize);
+  }
+}
+#else
+static void mi_stat_huge_free(const mi_page_t* page) {
+  MI_UNUSED(page);
+}
+#endif
+#endif
+
+// ------------------------------------------------------
+// Free
+// ------------------------------------------------------
+
+// multi-threaded free (or free in huge block if compiled with MI_HUGE_PAGE_ABANDON)
+static mi_decl_noinline void _mi_free_block_mt(mi_page_t* page, mi_block_t* block)
+{
+  // The padding check may access the non-thread-owned page for the key values.
+  // that is safe as these are constant and the page won't be freed (as the block is not freed yet).
+  mi_check_padding(page, block);
+  _mi_padding_shrink(page, block, sizeof(mi_block_t));       // for small size, ensure we can fit the delayed thread pointers without triggering overflow detection
+
+  // huge page segments are always abandoned and can be freed immediately
+  mi_segment_t* segment = _mi_page_segment(page);
+  if (segment->kind == MI_SEGMENT_HUGE) {
+    #if MI_HUGE_PAGE_ABANDON
+    // huge page segments are always abandoned and can be freed immediately
+    mi_stat_huge_free(page);
+    _mi_segment_huge_page_free(segment, page, block);
+    return;
+    #else
+    // huge pages are special as they occupy the entire segment
+    // as these are large we reset the memory occupied by the page so it is available to other threads
+    // (as the owning thread needs to actually free the memory later).
+    _mi_segment_huge_page_reset(segment, page, block);
+    #endif
+  }
+
+  #if (MI_DEBUG>0) && !MI_TRACK_ENABLED && !MI_TSAN        // note: when tracking, cannot use mi_usable_size with multi-threading
+  if (segment->kind != MI_SEGMENT_HUGE) {                  // not for huge segments as we just reset the content
+    memset(block, MI_DEBUG_FREED, mi_usable_size(block));
+  }
+  #endif
+
+  // Try to put the block on either the page-local thread free list, or the heap delayed free list.
+  mi_thread_free_t tfreex;
+  bool use_delayed;
+  mi_thread_free_t tfree = mi_atomic_load_relaxed(&page->xthread_free);
+  do {
+    use_delayed = (mi_tf_delayed(tfree) == MI_USE_DELAYED_FREE);
+    if mi_unlikely(use_delayed) {
+      // unlikely: this only happens on the first concurrent free in a page that is in the full list
+      tfreex = mi_tf_set_delayed(tfree,MI_DELAYED_FREEING);
+    }
+    else {
+      // usual: directly add to page thread_free list
+      mi_block_set_next(page, block, mi_tf_block(tfree));
+      tfreex = mi_tf_set_block(tfree,block);
+    }
+  } while (!mi_atomic_cas_weak_release(&page->xthread_free, &tfree, tfreex));
+
+  if mi_unlikely(use_delayed) {
+    // racy read on `heap`, but ok because MI_DELAYED_FREEING is set (see `mi_heap_delete` and `mi_heap_collect_abandon`)
+    mi_heap_t* const heap = (mi_heap_t*)(mi_atomic_load_acquire(&page->xheap)); //mi_page_heap(page);
+    mi_assert_internal(heap != NULL);
+    if (heap != NULL) {
+      // add to the delayed free list of this heap. (do this atomically as the lock only protects heap memory validity)
+      mi_block_t* dfree = mi_atomic_load_ptr_relaxed(mi_block_t, &heap->thread_delayed_free);
+      do {
+	mi_block_set_nextx(heap,block,dfree, heap->keys);
+      } while (!mi_atomic_cas_ptr_weak_release(mi_block_t,&heap->thread_delayed_free, &dfree, block));
+    }
+
+    // and reset the MI_DELAYED_FREEING flag
+    tfree = mi_atomic_load_relaxed(&page->xthread_free);
+    do {
+      tfreex = tfree;
+      mi_assert_internal(mi_tf_delayed(tfree) == MI_DELAYED_FREEING);
+      tfreex = mi_tf_set_delayed(tfree,MI_NO_DELAYED_FREE);
+    } while (!mi_atomic_cas_weak_release(&page->xthread_free, &tfree, tfreex));
+  }
+}
+
+// regular free
+static inline void _mi_free_block(mi_page_t* page, bool local, mi_block_t* block)
+{
+  // and push it on the free list
+  //const size_t bsize = mi_page_block_size(page);
+  if mi_likely(local) {
+    // owning thread can free a block directly
+    if mi_unlikely(mi_check_is_double_free(page, block)) return;
+    mi_check_padding(page, block);
+    #if (MI_DEBUG>0) && !MI_TRACK_ENABLED && !MI_TSAN
+    if (!mi_page_is_huge(page)) {   // huge page content may be already decommitted
+      memset(block, MI_DEBUG_FREED, mi_page_block_size(page));
+    }
+    #endif
+    mi_block_set_next(page, block, page->local_free);
+    page->local_free = block;
+    page->used--;
+    if mi_unlikely(mi_page_all_free(page)) {
+      _mi_page_retire(page);
+    }
+    else if mi_unlikely(mi_page_is_in_full(page)) {
+      _mi_page_unfull(page);
+    }
+  }
+  else {
+    _mi_free_block_mt(page,block);
+  }
+}
+
+
+// Adjust a block that was allocated aligned, to the actual start of the block in the page.
+mi_block_t* _mi_page_ptr_unalign(const mi_segment_t* segment, const mi_page_t* page, const void* p) {
+  mi_assert_internal(page!=NULL && p!=NULL);
+  const size_t diff   = (uint8_t*)p - _mi_page_start(segment, page, NULL);
+  const size_t adjust = (diff % mi_page_block_size(page));
+  return (mi_block_t*)((uintptr_t)p - adjust);
+}
+
+
+void mi_decl_noinline _mi_free_generic(const mi_segment_t* segment, mi_page_t* page, bool is_local, void* p) mi_attr_noexcept {
+  mi_block_t* const block = (mi_page_has_aligned(page) ? _mi_page_ptr_unalign(segment, page, p) : (mi_block_t*)p);
+  mi_stat_free(page, block);    // stat_free may access the padding
+  mi_track_free_size(block, mi_page_usable_size_of(page,block));
+  _mi_free_block(page, is_local, block);
+}
+
+// Get the segment data belonging to a pointer
+// This is just a single `and` in assembly but does further checks in debug mode
+// (and secure mode) if this was a valid pointer.
+static inline mi_segment_t* mi_checked_ptr_segment(const void* p, const char* msg)
+{
+  MI_UNUSED(msg);
+  mi_assert(p != NULL);
+
+#if (MI_DEBUG>0)
+  if mi_unlikely(((uintptr_t)p & (MI_INTPTR_SIZE - 1)) != 0) {
+    _mi_error_message(EINVAL, "%s: invalid (unaligned) pointer: %p\n", msg, p);
+    return NULL;
+  }
+#endif
+
+  mi_segment_t* const segment = _mi_ptr_segment(p);
+  mi_assert_internal(segment != NULL);
+
+#if (MI_DEBUG>0)
+  if mi_unlikely(!mi_is_in_heap_region(p)) {
+  #if (MI_INTPTR_SIZE == 8 && defined(__linux__))
+    if (((uintptr_t)p >> 40) != 0x7F) { // linux tends to align large blocks above 0x7F000000000 (issue #640)
+  #else
+    {
+  #endif
+      _mi_warning_message("%s: pointer might not point to a valid heap region: %p\n"
+	"(this may still be a valid very large allocation (over 64MiB))\n", msg, p);
+      if mi_likely(_mi_ptr_cookie(segment) == segment->cookie) {
+	_mi_warning_message("(yes, the previous pointer %p was valid after all)\n", p);
+      }
+    }
+  }
+#endif
+#if (MI_DEBUG>0 || MI_SECURE>=4)
+  if mi_unlikely(_mi_ptr_cookie(segment) != segment->cookie) {
+    _mi_error_message(EINVAL, "%s: pointer does not point to a valid heap space: %p\n", msg, p);
+    return NULL;
+  }
+#endif
+
+  return segment;
+}
+
+// Free a block
+// fast path written carefully to prevent spilling on the stack
+void mi_free(void* p) mi_attr_noexcept
+{
+  if mi_unlikely(p == NULL) return;
+  mi_segment_t* const segment = mi_checked_ptr_segment(p,"mi_free");
+  const bool          is_local= (_mi_prim_thread_id() == mi_atomic_load_relaxed(&segment->thread_id));
+  mi_page_t* const    page    = _mi_segment_page_of(segment, p);
+
+  if mi_likely(is_local) {                       // thread-local free?
+    if mi_likely(page->flags.full_aligned == 0)  // and it is not a full page (full pages need to move from the full bin), nor has aligned blocks (aligned blocks need to be unaligned)
+    {
+      mi_block_t* const block = (mi_block_t*)p;
+      if mi_unlikely(mi_check_is_double_free(page, block)) return;
+      mi_check_padding(page, block);
+      mi_stat_free(page, block);
+      #if (MI_DEBUG>0) && !MI_TRACK_ENABLED  && !MI_TSAN
+      memset(block, MI_DEBUG_FREED, mi_page_block_size(page));
+      #endif
+      mi_track_free_size(p, mi_page_usable_size_of(page,block)); // faster then mi_usable_size as we already know the page and that p is unaligned
+      mi_block_set_next(page, block, page->local_free);
+      page->local_free = block;
+      if mi_unlikely(--page->used == 0) {   // using this expression generates better code than: page->used--; if (mi_page_all_free(page))
+	_mi_page_retire(page);
+      }
+    }
+    else {
+      // page is full or contains (inner) aligned blocks; use generic path
+      _mi_free_generic(segment, page, true, p);
+    }
+  }
+  else {
+    // not thread-local; use generic path
+    _mi_free_generic(segment, page, false, p);
+  }
+}
+
+// return true if successful
+bool _mi_free_delayed_block(mi_block_t* block) {
+  // get segment and page
+  const mi_segment_t* const segment = _mi_ptr_segment(block);
+  mi_assert_internal(_mi_ptr_cookie(segment) == segment->cookie);
+  mi_assert_internal(_mi_thread_id() == segment->thread_id);
+  mi_page_t* const page = _mi_segment_page_of(segment, block);
+
+  // Clear the no-delayed flag so delayed freeing is used again for this page.
+  // This must be done before collecting the free lists on this page -- otherwise
+  // some blocks may end up in the page `thread_free` list with no blocks in the
+  // heap `thread_delayed_free` list which may cause the page to be never freed!
+  // (it would only be freed if we happen to scan it in `mi_page_queue_find_free_ex`)
+  if (!_mi_page_try_use_delayed_free(page, MI_USE_DELAYED_FREE, false /* dont overwrite never delayed */)) {
+    return false;
+  }
+
+  // collect all other non-local frees to ensure up-to-date `used` count
+  _mi_page_free_collect(page, false);
+
+  // and free the block (possibly freeing the page as well since used is updated)
+  _mi_free_block(page, true, block);
+  return true;
+}
+
+// Bytes available in a block
+mi_decl_noinline static size_t mi_page_usable_aligned_size_of(const mi_segment_t* segment, const mi_page_t* page, const void* p) mi_attr_noexcept {
+  const mi_block_t* block = _mi_page_ptr_unalign(segment, page, p);
+  const size_t size = mi_page_usable_size_of(page, block);
+  const ptrdiff_t adjust = (uint8_t*)p - (uint8_t*)block;
+  mi_assert_internal(adjust >= 0 && (size_t)adjust <= size);
+  return (size - adjust);
+}
+
+static inline size_t _mi_usable_size(const void* p, const char* msg) mi_attr_noexcept {
+  if (p == NULL) return 0;
+  const mi_segment_t* const segment = mi_checked_ptr_segment(p, msg);
+  const mi_page_t* const page = _mi_segment_page_of(segment, p);
+  if mi_likely(!mi_page_has_aligned(page)) {
+    const mi_block_t* block = (const mi_block_t*)p;
+    return mi_page_usable_size_of(page, block);
+  }
+  else {
+    // split out to separate routine for improved code generation
+    return mi_page_usable_aligned_size_of(segment, page, p);
+  }
+}
+
+mi_decl_nodiscard size_t mi_usable_size(const void* p) mi_attr_noexcept {
+  return _mi_usable_size(p, "mi_usable_size");
+}
+
+
+// ------------------------------------------------------
+// Allocation extensions
+// ------------------------------------------------------
+
+void mi_free_size(void* p, size_t size) mi_attr_noexcept {
+  MI_UNUSED_RELEASE(size);
+  mi_assert(p == NULL || size <= _mi_usable_size(p,"mi_free_size"));
+  mi_free(p);
+}
+
+void mi_free_size_aligned(void* p, size_t size, size_t alignment) mi_attr_noexcept {
+  MI_UNUSED_RELEASE(alignment);
+  mi_assert(((uintptr_t)p % alignment) == 0);
+  mi_free_size(p,size);
+}
+
+void mi_free_aligned(void* p, size_t alignment) mi_attr_noexcept {
+  MI_UNUSED_RELEASE(alignment);
+  mi_assert(((uintptr_t)p % alignment) == 0);
+  mi_free(p);
+}
+
+mi_decl_nodiscard extern inline mi_decl_restrict void* mi_heap_calloc(mi_heap_t* heap, size_t count, size_t size) mi_attr_noexcept {
+  size_t total;
+  if (mi_count_size_overflow(count,size,&total)) return NULL;
+  return mi_heap_zalloc(heap,total);
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_calloc(size_t count, size_t size) mi_attr_noexcept {
+  return mi_heap_calloc(mi_prim_get_default_heap(),count,size);
+}
+
+// Uninitialized `calloc`
+mi_decl_nodiscard extern mi_decl_restrict void* mi_heap_mallocn(mi_heap_t* heap, size_t count, size_t size) mi_attr_noexcept {
+  size_t total;
+  if (mi_count_size_overflow(count, size, &total)) return NULL;
+  return mi_heap_malloc(heap, total);
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_mallocn(size_t count, size_t size) mi_attr_noexcept {
+  return mi_heap_mallocn(mi_prim_get_default_heap(),count,size);
+}
+
+// Expand (or shrink) in place (or fail)
+void* mi_expand(void* p, size_t newsize) mi_attr_noexcept {
+  #if MI_PADDING
+  // we do not shrink/expand with padding enabled
+  MI_UNUSED(p); MI_UNUSED(newsize);
+  return NULL;
+  #else
+  if (p == NULL) return NULL;
+  const size_t size = _mi_usable_size(p,"mi_expand");
+  if (newsize > size) return NULL;
+  return p; // it fits
+  #endif
+}
+
+void* _mi_heap_realloc_zero(mi_heap_t* heap, void* p, size_t newsize, bool zero) mi_attr_noexcept {
+  // if p == NULL then behave as malloc.
+  // else if size == 0 then reallocate to a zero-sized block (and don't return NULL, just as mi_malloc(0)).
+  // (this means that returning NULL always indicates an error, and `p` will not have been freed in that case.)
+  const size_t size = _mi_usable_size(p,"mi_realloc"); // also works if p == NULL (with size 0)
+  if mi_unlikely(newsize <= size && newsize >= (size / 2) && newsize > 0) {  // note: newsize must be > 0 or otherwise we return NULL for realloc(NULL,0)
+    mi_assert_internal(p!=NULL);
+    // todo: do not track as the usable size is still the same in the free; adjust potential padding?
+    // mi_track_resize(p,size,newsize)
+    // if (newsize < size) { mi_track_mem_noaccess((uint8_t*)p + newsize, size - newsize); }
+    return p;  // reallocation still fits and not more than 50% waste
+  }
+  void* newp = mi_heap_malloc(heap,newsize);
+  if mi_likely(newp != NULL) {
+    if (zero && newsize > size) {
+      // also set last word in the previous allocation to zero to ensure any padding is zero-initialized
+      const size_t start = (size >= sizeof(intptr_t) ? size - sizeof(intptr_t) : 0);
+      _mi_memzero((uint8_t*)newp + start, newsize - start);
+    }
+    else if (newsize == 0) {
+      ((uint8_t*)newp)[0] = 0; // work around for applications that expect zero-reallocation to be zero initialized (issue #725)
+    }
+    if mi_likely(p != NULL) {
+      const size_t copysize = (newsize > size ? size : newsize);
+      mi_track_mem_defined(p,copysize);  // _mi_useable_size may be too large for byte precise memory tracking..
+      _mi_memcpy(newp, p, copysize);
+      mi_free(p); // only free the original pointer if successful
+    }
+  }
+  return newp;
+}
+
+mi_decl_nodiscard void* mi_heap_realloc(mi_heap_t* heap, void* p, size_t newsize) mi_attr_noexcept {
+  return _mi_heap_realloc_zero(heap, p, newsize, false);
+}
+
+mi_decl_nodiscard void* mi_heap_reallocn(mi_heap_t* heap, void* p, size_t count, size_t size) mi_attr_noexcept {
+  size_t total;
+  if (mi_count_size_overflow(count, size, &total)) return NULL;
+  return mi_heap_realloc(heap, p, total);
+}
+
+
+// Reallocate but free `p` on errors
+mi_decl_nodiscard void* mi_heap_reallocf(mi_heap_t* heap, void* p, size_t newsize) mi_attr_noexcept {
+  void* newp = mi_heap_realloc(heap, p, newsize);
+  if (newp==NULL && p!=NULL) mi_free(p);
+  return newp;
+}
+
+mi_decl_nodiscard void* mi_heap_rezalloc(mi_heap_t* heap, void* p, size_t newsize) mi_attr_noexcept {
+  return _mi_heap_realloc_zero(heap, p, newsize, true);
+}
+
+mi_decl_nodiscard void* mi_heap_recalloc(mi_heap_t* heap, void* p, size_t count, size_t size) mi_attr_noexcept {
+  size_t total;
+  if (mi_count_size_overflow(count, size, &total)) return NULL;
+  return mi_heap_rezalloc(heap, p, total);
+}
+
+
+mi_decl_nodiscard void* mi_realloc(void* p, size_t newsize) mi_attr_noexcept {
+  return mi_heap_realloc(mi_prim_get_default_heap(),p,newsize);
+}
+
+mi_decl_nodiscard void* mi_reallocn(void* p, size_t count, size_t size) mi_attr_noexcept {
+  return mi_heap_reallocn(mi_prim_get_default_heap(),p,count,size);
+}
+
+// Reallocate but free `p` on errors
+mi_decl_nodiscard void* mi_reallocf(void* p, size_t newsize) mi_attr_noexcept {
+  return mi_heap_reallocf(mi_prim_get_default_heap(),p,newsize);
+}
+
+mi_decl_nodiscard void* mi_rezalloc(void* p, size_t newsize) mi_attr_noexcept {
+  return mi_heap_rezalloc(mi_prim_get_default_heap(), p, newsize);
+}
+
+mi_decl_nodiscard void* mi_recalloc(void* p, size_t count, size_t size) mi_attr_noexcept {
+  return mi_heap_recalloc(mi_prim_get_default_heap(), p, count, size);
+}
+
+
+
+// ------------------------------------------------------
+// strdup, strndup, and realpath
+// ------------------------------------------------------
+
+// `strdup` using mi_malloc
+mi_decl_nodiscard mi_decl_restrict char* mi_heap_strdup(mi_heap_t* heap, const char* s) mi_attr_noexcept {
+  if (s == NULL) return NULL;
+  size_t n = strlen(s);
+  char* t = (char*)mi_heap_malloc(heap,n+1);
+  if (t == NULL) return NULL;
+  _mi_memcpy(t, s, n);
+  t[n] = 0;
+  return t;
+}
+
+mi_decl_nodiscard mi_decl_restrict char* mi_strdup(const char* s) mi_attr_noexcept {
+  return mi_heap_strdup(mi_prim_get_default_heap(), s);
+}
+
+// `strndup` using mi_malloc
+mi_decl_nodiscard mi_decl_restrict char* mi_heap_strndup(mi_heap_t* heap, const char* s, size_t n) mi_attr_noexcept {
+  if (s == NULL) return NULL;
+  const char* end = (const char*)memchr(s, 0, n);  // find end of string in the first `n` characters (returns NULL if not found)
+  const size_t m = (end != NULL ? (size_t)(end - s) : n);  // `m` is the minimum of `n` or the end-of-string
+  mi_assert_internal(m <= n);
+  char* t = (char*)mi_heap_malloc(heap, m+1);
+  if (t == NULL) return NULL;
+  _mi_memcpy(t, s, m);
+  t[m] = 0;
+  return t;
+}
+
+mi_decl_nodiscard mi_decl_restrict char* mi_strndup(const char* s, size_t n) mi_attr_noexcept {
+  return mi_heap_strndup(mi_prim_get_default_heap(),s,n);
+}
+
+#ifndef __wasi__
+// `realpath` using mi_malloc
+#ifdef _WIN32
+#ifndef PATH_MAX
+#define PATH_MAX MAX_PATH
+#endif
+#include <windows.h>
+mi_decl_nodiscard mi_decl_restrict char* mi_heap_realpath(mi_heap_t* heap, const char* fname, char* resolved_name) mi_attr_noexcept {
+  // todo: use GetFullPathNameW to allow longer file names
+  char buf[PATH_MAX];
+  DWORD res = GetFullPathNameA(fname, PATH_MAX, (resolved_name == NULL ? buf : resolved_name), NULL);
+  if (res == 0) {
+    errno = GetLastError(); return NULL;
+  }
+  else if (res > PATH_MAX) {
+    errno = EINVAL; return NULL;
+  }
+  else if (resolved_name != NULL) {
+    return resolved_name;
+  }
+  else {
+    return mi_heap_strndup(heap, buf, PATH_MAX);
+  }
+}
+#else
+/*
+#include <unistd.h>  // pathconf
+static size_t mi_path_max(void) {
+  static size_t path_max = 0;
+  if (path_max <= 0) {
+    long m = pathconf("/",_PC_PATH_MAX);
+    if (m <= 0) path_max = 4096;      // guess
+    else if (m < 256) path_max = 256; // at least 256
+    else path_max = m;
+  }
+  return path_max;
+}
+*/
+char* mi_heap_realpath(mi_heap_t* heap, const char* fname, char* resolved_name) mi_attr_noexcept {
+  if (resolved_name != NULL) {
+    return realpath(fname,resolved_name);
+  }
+  else {
+    char* rname = realpath(fname, NULL);
+    if (rname == NULL) return NULL;
+    char* result = mi_heap_strdup(heap, rname);
+    free(rname);  // use regular free! (which may be redirected to our free but that's ok)
+    return result;
+  }
+  /*
+    const size_t n  = mi_path_max();
+    char* buf = (char*)mi_malloc(n+1);
+    if (buf == NULL) {
+      errno = ENOMEM;
+      return NULL;
+    }
+    char* rname  = realpath(fname,buf);
+    char* result = mi_heap_strndup(heap,rname,n); // ok if `rname==NULL`
+    mi_free(buf);
+    return result;
+  }
+  */
+}
+#endif
+
+mi_decl_nodiscard mi_decl_restrict char* mi_realpath(const char* fname, char* resolved_name) mi_attr_noexcept {
+  return mi_heap_realpath(mi_prim_get_default_heap(),fname,resolved_name);
+}
+#endif
+
+/*-------------------------------------------------------
+C++ new and new_aligned
+The standard requires calling into `get_new_handler` and
+throwing the bad_alloc exception on failure. If we compile
+with a C++ compiler we can implement this precisely. If we
+use a C compiler we cannot throw a `bad_alloc` exception
+but we call `exit` instead (i.e. not returning).
+-------------------------------------------------------*/
+
+#ifdef __cplusplus
+#include <new>
+static bool mi_try_new_handler(bool nothrow) {
+  #if defined(_MSC_VER) || (__cplusplus >= 201103L)
+    std::new_handler h = std::get_new_handler();
+  #else
+    std::new_handler h = std::set_new_handler();
+    std::set_new_handler(h);
+  #endif
+  if (h==NULL) {
+    _mi_error_message(ENOMEM, "out of memory in 'new'");
+    if (!nothrow) {
+      throw std::bad_alloc();
+    }
+    return false;
+  }
+  else {
+    h();
+    return true;
+  }
+}
+#else
+typedef void (*std_new_handler_t)(void);
+
+#if (defined(__GNUC__) || (defined(__clang__) && !defined(_MSC_VER)))  // exclude clang-cl, see issue #631
+std_new_handler_t __attribute__((weak)) _ZSt15get_new_handlerv(void) {
+  return NULL;
+}
+static std_new_handler_t mi_get_new_handler(void) {
+  return _ZSt15get_new_handlerv();
+}
+#else
+// note: on windows we could dynamically link to `?get_new_handler@std@@YAP6AXXZXZ`.
+static std_new_handler_t mi_get_new_handler() {
+  return NULL;
+}
+#endif
+
+static bool mi_try_new_handler(bool nothrow) {
+  std_new_handler_t h = mi_get_new_handler();
+  if (h==NULL) {
+    _mi_error_message(ENOMEM, "out of memory in 'new'");
+    if (!nothrow) {
+      abort();  // cannot throw in plain C, use abort
+    }
+    return false;
+  }
+  else {
+    h();
+    return true;
+  }
+}
+#endif
+
+mi_decl_export mi_decl_noinline void* mi_heap_try_new(mi_heap_t* heap, size_t size, bool nothrow ) {
+  void* p = NULL;
+  while(p == NULL && mi_try_new_handler(nothrow)) {
+    p = mi_heap_malloc(heap,size);
+  }
+  return p;
+}
+
+static mi_decl_noinline void* mi_try_new(size_t size, bool nothrow) {
+  return mi_heap_try_new(mi_prim_get_default_heap(), size, nothrow);
+}
+
+
+mi_decl_nodiscard mi_decl_restrict void* mi_heap_alloc_new(mi_heap_t* heap, size_t size) {
+  void* p = mi_heap_malloc(heap,size);
+  if mi_unlikely(p == NULL) return mi_heap_try_new(heap, size, false);
+  return p;
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_new(size_t size) {
+  return mi_heap_alloc_new(mi_prim_get_default_heap(), size);
+}
+
+
+mi_decl_nodiscard mi_decl_restrict void* mi_heap_alloc_new_n(mi_heap_t* heap, size_t count, size_t size) {
+  size_t total;
+  if mi_unlikely(mi_count_size_overflow(count, size, &total)) {
+    mi_try_new_handler(false);  // on overflow we invoke the try_new_handler once to potentially throw std::bad_alloc
+    return NULL;
+  }
+  else {
+    return mi_heap_alloc_new(heap,total);
+  }
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_new_n(size_t count, size_t size) {
+  return mi_heap_alloc_new_n(mi_prim_get_default_heap(), size, count);
+}
+
+
+mi_decl_nodiscard mi_decl_restrict void* mi_new_nothrow(size_t size) mi_attr_noexcept {
+  void* p = mi_malloc(size);
+  if mi_unlikely(p == NULL) return mi_try_new(size, true);
+  return p;
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_new_aligned(size_t size, size_t alignment) {
+  void* p;
+  do {
+    p = mi_malloc_aligned(size, alignment);
+  }
+  while(p == NULL && mi_try_new_handler(false));
+  return p;
+}
+
+mi_decl_nodiscard mi_decl_restrict void* mi_new_aligned_nothrow(size_t size, size_t alignment) mi_attr_noexcept {
+  void* p;
+  do {
+    p = mi_malloc_aligned(size, alignment);
+  }
+  while(p == NULL && mi_try_new_handler(true));
+  return p;
+}
+
+mi_decl_nodiscard void* mi_new_realloc(void* p, size_t newsize) {
+  void* q;
+  do {
+    q = mi_realloc(p, newsize);
+  } while (q == NULL && mi_try_new_handler(false));
+  return q;
+}
+
+mi_decl_nodiscard void* mi_new_reallocn(void* p, size_t newcount, size_t size) {
+  size_t total;
+  if mi_unlikely(mi_count_size_overflow(newcount, size, &total)) {
+    mi_try_new_handler(false);  // on overflow we invoke the try_new_handler once to potentially throw std::bad_alloc
+    return NULL;
+  }
+  else {
+    return mi_new_realloc(p, total);
+  }
+}
+
+// ------------------------------------------------------
+// ensure explicit external inline definitions are emitted!
+// ------------------------------------------------------
+
+#ifdef __cplusplus
+void* _mi_externs[] = {
+  (void*)&_mi_page_malloc,
+  (void*)&_mi_heap_malloc_zero,
+  (void*)&_mi_heap_malloc_zero_ex,
+  (void*)&mi_malloc,
+  (void*)&mi_malloc_small,
+  (void*)&mi_zalloc_small,
+  (void*)&mi_heap_malloc,
+  (void*)&mi_heap_zalloc,
+  (void*)&mi_heap_malloc_small,
+  // (void*)&mi_heap_alloc_new,
+  // (void*)&mi_heap_alloc_new_n
+};
+#endif
diff --git a/compat/mimalloc/arena.c b/compat/mimalloc/arena.c
new file mode 100644
index 00000000000000..879ee9e7e773d4
--- /dev/null
+++ b/compat/mimalloc/arena.c
@@ -0,0 +1,935 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2019-2023, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+
+/* ----------------------------------------------------------------------------
+"Arenas" are fixed area's of OS memory from which we can allocate
+large blocks (>= MI_ARENA_MIN_BLOCK_SIZE, 4MiB).
+In contrast to the rest of mimalloc, the arenas are shared between
+threads and need to be accessed using atomic operations.
+
+Arenas are used to for huge OS page (1GiB) reservations or for reserving
+OS memory upfront which can be improve performance or is sometimes needed
+on embedded devices. We can also employ this with WASI or `sbrk` systems
+to reserve large arenas upfront and be able to reuse the memory more effectively.
+
+The arena allocation needs to be thread safe and we use an atomic bitmap to allocate.
+-----------------------------------------------------------------------------*/
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "mimalloc/atomic.h"
+
+#include <string.h>  // memset
+#include <errno.h>   // ENOMEM
+
+#include "bitmap.h"  // atomic bitmap
+
+/* -----------------------------------------------------------
+  Arena allocation
+----------------------------------------------------------- */
+
+// Block info: bit 0 contains the `in_use` bit, the upper bits the
+// size in count of arena blocks.
+typedef uintptr_t mi_block_info_t;
+#define MI_ARENA_BLOCK_SIZE   (MI_SEGMENT_SIZE)        // 64MiB  (must be at least MI_SEGMENT_ALIGN)
+#define MI_ARENA_MIN_OBJ_SIZE (MI_ARENA_BLOCK_SIZE/2)  // 32MiB
+#define MI_MAX_ARENAS         (112)                    // not more than 126 (since we use 7 bits in the memid and an arena index + 1)
+
+// A memory arena descriptor
+typedef struct mi_arena_s {
+  mi_arena_id_t id;                       // arena id; 0 for non-specific
+  mi_memid_t memid;                       // memid of the memory area
+  _Atomic(uint8_t*) start;                // the start of the memory area
+  size_t   block_count;                   // size of the area in arena blocks (of `MI_ARENA_BLOCK_SIZE`)
+  size_t   field_count;                   // number of bitmap fields (where `field_count * MI_BITMAP_FIELD_BITS >= block_count`)
+  size_t   meta_size;                     // size of the arena structure itself (including its bitmaps)
+  mi_memid_t meta_memid;                  // memid of the arena structure itself (OS or static allocation)
+  int      numa_node;                     // associated NUMA node
+  bool     exclusive;                     // only allow allocations if specifically for this arena
+  bool     is_large;                      // memory area consists of large- or huge OS pages (always committed)
+  _Atomic(size_t) search_idx;             // optimization to start the search for free blocks
+  _Atomic(mi_msecs_t) purge_expire;       // expiration time when blocks should be decommitted from `blocks_decommit`.
+  mi_bitmap_field_t* blocks_dirty;        // are the blocks potentially non-zero?
+  mi_bitmap_field_t* blocks_committed;    // are the blocks committed? (can be NULL for memory that cannot be decommitted)
+  mi_bitmap_field_t* blocks_purge;        // blocks that can be (reset) decommitted. (can be NULL for memory that cannot be (reset) decommitted)
+  mi_bitmap_field_t  blocks_inuse[1];     // in-place bitmap of in-use blocks (of size `field_count`)
+} mi_arena_t;
+
+
+// The available arenas
+static mi_decl_cache_align _Atomic(mi_arena_t*) mi_arenas[MI_MAX_ARENAS];
+static mi_decl_cache_align _Atomic(size_t)      mi_arena_count; // = 0
+
+
+//static bool mi_manage_os_memory_ex2(void* start, size_t size, bool is_large, int numa_node, bool exclusive, mi_memid_t memid, mi_arena_id_t* arena_id) mi_attr_noexcept;
+
+/* -----------------------------------------------------------
+  Arena id's
+  id = arena_index + 1
+----------------------------------------------------------- */
+
+static size_t mi_arena_id_index(mi_arena_id_t id) {
+  return (size_t)(id <= 0 ? MI_MAX_ARENAS : id - 1);
+}
+
+static mi_arena_id_t mi_arena_id_create(size_t arena_index) {
+  mi_assert_internal(arena_index < MI_MAX_ARENAS);
+  return (int)arena_index + 1;
+}
+
+mi_arena_id_t _mi_arena_id_none(void) {
+  return 0;
+}
+
+static bool mi_arena_id_is_suitable(mi_arena_id_t arena_id, bool arena_is_exclusive, mi_arena_id_t req_arena_id) {
+  return ((!arena_is_exclusive && req_arena_id == _mi_arena_id_none()) ||
+	  (arena_id == req_arena_id));
+}
+
+bool _mi_arena_memid_is_suitable(mi_memid_t memid, mi_arena_id_t request_arena_id) {
+  if (memid.memkind == MI_MEM_ARENA) {
+    return mi_arena_id_is_suitable(memid.mem.arena.id, memid.mem.arena.is_exclusive, request_arena_id);
+  }
+  else {
+    return mi_arena_id_is_suitable(0, false, request_arena_id);
+  }
+}
+
+bool _mi_arena_memid_is_os_allocated(mi_memid_t memid) {
+  return (memid.memkind == MI_MEM_OS);
+}
+
+/* -----------------------------------------------------------
+  Arena allocations get a (currently) 16-bit memory id where the
+  lower 8 bits are the arena id, and the upper bits the block index.
+----------------------------------------------------------- */
+
+static size_t mi_block_count_of_size(size_t size) {
+  return _mi_divide_up(size, MI_ARENA_BLOCK_SIZE);
+}
+
+static size_t mi_arena_block_size(size_t bcount) {
+  return (bcount * MI_ARENA_BLOCK_SIZE);
+}
+
+static size_t mi_arena_size(mi_arena_t* arena) {
+  return mi_arena_block_size(arena->block_count);
+}
+
+static mi_memid_t mi_memid_create_arena(mi_arena_id_t id, bool is_exclusive, mi_bitmap_index_t bitmap_index) {
+  mi_memid_t memid = _mi_memid_create(MI_MEM_ARENA);
+  memid.mem.arena.id = id;
+  memid.mem.arena.block_index = bitmap_index;
+  memid.mem.arena.is_exclusive = is_exclusive;
+  return memid;
+}
+
+static bool mi_arena_memid_indices(mi_memid_t memid, size_t* arena_index, mi_bitmap_index_t* bitmap_index) {
+  mi_assert_internal(memid.memkind == MI_MEM_ARENA);
+  *arena_index = mi_arena_id_index(memid.mem.arena.id);
+  *bitmap_index = memid.mem.arena.block_index;
+  return memid.mem.arena.is_exclusive;
+}
+
+
+
+/* -----------------------------------------------------------
+  Special static area for mimalloc internal structures
+  to avoid OS calls (for example, for the arena metadata)
+----------------------------------------------------------- */
+
+#define MI_ARENA_STATIC_MAX  (MI_INTPTR_SIZE*MI_KiB)  // 8 KiB on 64-bit
+
+static uint8_t mi_arena_static[MI_ARENA_STATIC_MAX];
+static _Atomic(size_t) mi_arena_static_top;
+
+static void* mi_arena_static_zalloc(size_t size, size_t alignment, mi_memid_t* memid) {
+  *memid = _mi_memid_none();
+  if (size == 0 || size > MI_ARENA_STATIC_MAX) return NULL;
+  if ((mi_atomic_load_relaxed(&mi_arena_static_top) + size) > MI_ARENA_STATIC_MAX) return NULL;
+
+  // try to claim space
+  if (alignment == 0) { alignment = 1; }
+  const size_t oversize = size + alignment - 1;
+  if (oversize > MI_ARENA_STATIC_MAX) return NULL;
+  const size_t oldtop = mi_atomic_add_acq_rel(&mi_arena_static_top, oversize);
+  size_t top = oldtop + oversize;
+  if (top > MI_ARENA_STATIC_MAX) {
+    // try to roll back, ok if this fails
+    mi_atomic_cas_strong_acq_rel(&mi_arena_static_top, &top, oldtop);
+    return NULL;
+  }
+
+  // success
+  *memid = _mi_memid_create(MI_MEM_STATIC);
+  const size_t start = _mi_align_up(oldtop, alignment);
+  uint8_t* const p = &mi_arena_static[start];
+  _mi_memzero(p, size);
+  return p;
+}
+
+static void* mi_arena_meta_zalloc(size_t size, mi_memid_t* memid, mi_stats_t* stats) {
+  *memid = _mi_memid_none();
+
+  // try static
+  void* p = mi_arena_static_zalloc(size, MI_ALIGNMENT_MAX, memid);
+  if (p != NULL) return p;
+
+  // or fall back to the OS
+  return _mi_os_alloc(size, memid, stats);
+}
+
+static void mi_arena_meta_free(void* p, mi_memid_t memid, size_t size, mi_stats_t* stats) {
+  if (mi_memkind_is_os(memid.memkind)) {
+    _mi_os_free(p, size, memid, stats);
+  }
+  else {
+    mi_assert(memid.memkind == MI_MEM_STATIC);
+  }
+}
+
+static void* mi_arena_block_start(mi_arena_t* arena, mi_bitmap_index_t bindex) {
+  return (arena->start + mi_arena_block_size(mi_bitmap_index_bit(bindex)));
+}
+
+
+/* -----------------------------------------------------------
+  Thread safe allocation in an arena
+----------------------------------------------------------- */
+
+// claim the `blocks_inuse` bits
+static bool mi_arena_try_claim(mi_arena_t* arena, size_t blocks, mi_bitmap_index_t* bitmap_idx)
+{
+  size_t idx = 0; // mi_atomic_load_relaxed(&arena->search_idx);  // start from last search; ok to be relaxed as the exact start does not matter
+  if (_mi_bitmap_try_find_from_claim_across(arena->blocks_inuse, arena->field_count, idx, blocks, bitmap_idx)) {
+    mi_atomic_store_relaxed(&arena->search_idx, mi_bitmap_index_field(*bitmap_idx));  // start search from found location next time around
+    return true;
+  };
+  return false;
+}
+
+
+/* -----------------------------------------------------------
+  Arena Allocation
+----------------------------------------------------------- */
+
+static mi_decl_noinline void* mi_arena_try_alloc_at(mi_arena_t* arena, size_t arena_index, size_t needed_bcount,
+						    bool commit, mi_memid_t* memid, mi_os_tld_t* tld)
+{
+  MI_UNUSED(arena_index);
+  mi_assert_internal(mi_arena_id_index(arena->id) == arena_index);
+
+  mi_bitmap_index_t bitmap_index;
+  if (!mi_arena_try_claim(arena, needed_bcount, &bitmap_index)) return NULL;
+
+  // claimed it!
+  void* p = mi_arena_block_start(arena, bitmap_index);
+  *memid = mi_memid_create_arena(arena->id, arena->exclusive, bitmap_index);
+  memid->is_pinned = arena->memid.is_pinned;
+
+  // none of the claimed blocks should be scheduled for a decommit
+  if (arena->blocks_purge != NULL) {
+    // this is thread safe as a potential purge only decommits parts that are not yet claimed as used (in `blocks_inuse`).
+    _mi_bitmap_unclaim_across(arena->blocks_purge, arena->field_count, needed_bcount, bitmap_index);
+  }
+
+  // set the dirty bits (todo: no need for an atomic op here?)
+  if (arena->memid.initially_zero && arena->blocks_dirty != NULL) {
+    memid->initially_zero = _mi_bitmap_claim_across(arena->blocks_dirty, arena->field_count, needed_bcount, bitmap_index, NULL);
+  }
+
+  // set commit state
+  if (arena->blocks_committed == NULL) {
+    // always committed
+    memid->initially_committed = true;
+  }
+  else if (commit) {
+    // commit requested, but the range may not be committed as a whole: ensure it is committed now
+    memid->initially_committed = true;
+    bool any_uncommitted;
+    _mi_bitmap_claim_across(arena->blocks_committed, arena->field_count, needed_bcount, bitmap_index, &any_uncommitted);
+    if (any_uncommitted) {
+      bool commit_zero = false;
+      if (!_mi_os_commit(p, mi_arena_block_size(needed_bcount), &commit_zero, tld->stats)) {
+	memid->initially_committed = false;
+      }
+      else {
+	if (commit_zero) { memid->initially_zero = true; }
+      }
+    }
+  }
+  else {
+    // no need to commit, but check if already fully committed
+    memid->initially_committed = _mi_bitmap_is_claimed_across(arena->blocks_committed, arena->field_count, needed_bcount, bitmap_index);
+  }
+
+  return p;
+}
+
+// allocate in a speficic arena
+static void* mi_arena_try_alloc_at_id(mi_arena_id_t arena_id, bool match_numa_node, int numa_node, size_t size, size_t alignment,
+				       bool commit, bool allow_large, mi_arena_id_t req_arena_id, mi_memid_t* memid, mi_os_tld_t* tld )
+{
+  MI_UNUSED_RELEASE(alignment);
+  mi_assert_internal(alignment <= MI_SEGMENT_ALIGN);
+  const size_t bcount = mi_block_count_of_size(size);
+  const size_t arena_index = mi_arena_id_index(arena_id);
+  mi_assert_internal(arena_index < mi_atomic_load_relaxed(&mi_arena_count));
+  mi_assert_internal(size <= mi_arena_block_size(bcount));
+
+  // Check arena suitability
+  mi_arena_t* arena = mi_atomic_load_ptr_acquire(mi_arena_t, &mi_arenas[arena_index]);
+  if (arena == NULL) return NULL;
+  if (!allow_large && arena->is_large) return NULL;
+  if (!mi_arena_id_is_suitable(arena->id, arena->exclusive, req_arena_id)) return NULL;
+  if (req_arena_id == _mi_arena_id_none()) { // in not specific, check numa affinity
+    const bool numa_suitable = (numa_node < 0 || arena->numa_node < 0 || arena->numa_node == numa_node);
+    if (match_numa_node) { if (!numa_suitable) return NULL; }
+		    else { if (numa_suitable) return NULL; }
+  }
+
+  // try to allocate
+  void* p = mi_arena_try_alloc_at(arena, arena_index, bcount, commit, memid, tld);
+  mi_assert_internal(p == NULL || _mi_is_aligned(p, alignment));
+  return p;
+}
+
+
+// allocate from an arena with fallback to the OS
+static mi_decl_noinline void* mi_arena_try_alloc(int numa_node, size_t size, size_t alignment,
+						  bool commit, bool allow_large,
+						  mi_arena_id_t req_arena_id, mi_memid_t* memid, mi_os_tld_t* tld )
+{
+  MI_UNUSED(alignment);
+  mi_assert_internal(alignment <= MI_SEGMENT_ALIGN);
+  const size_t max_arena = mi_atomic_load_relaxed(&mi_arena_count);
+  if mi_likely(max_arena == 0) return NULL;
+
+  if (req_arena_id != _mi_arena_id_none()) {
+    // try a specific arena if requested
+    if (mi_arena_id_index(req_arena_id) < max_arena) {
+      void* p = mi_arena_try_alloc_at_id(req_arena_id, true, numa_node, size, alignment, commit, allow_large, req_arena_id, memid, tld);
+      if (p != NULL) return p;
+    }
+  }
+  else {
+    // try numa affine allocation
+    for (size_t i = 0; i < max_arena; i++) {
+      void* p = mi_arena_try_alloc_at_id(mi_arena_id_create(i), true, numa_node, size, alignment, commit, allow_large, req_arena_id, memid, tld);
+      if (p != NULL) return p;
+    }
+
+    // try from another numa node instead..
+    if (numa_node >= 0) {  // if numa_node was < 0 (no specific affinity requested), all arena's have been tried already
+      for (size_t i = 0; i < max_arena; i++) {
+	void* p = mi_arena_try_alloc_at_id(mi_arena_id_create(i), false /* only proceed if not numa local */, numa_node, size, alignment, commit, allow_large, req_arena_id, memid, tld);
+	if (p != NULL) return p;
+      }
+    }
+  }
+  return NULL;
+}
+
+// try to reserve a fresh arena space
+static bool mi_arena_reserve(size_t req_size, bool allow_large, mi_arena_id_t req_arena_id, mi_arena_id_t *arena_id)
+{
+  if (_mi_preloading()) return false;  // use OS only while pre loading
+  if (req_arena_id != _mi_arena_id_none()) return false;
+
+  const size_t arena_count = mi_atomic_load_acquire(&mi_arena_count);
+  if (arena_count > (MI_MAX_ARENAS - 4)) return false;
+
+  size_t arena_reserve = mi_option_get_size(mi_option_arena_reserve);
+  if (arena_reserve == 0) return false;
+
+  if (!_mi_os_has_virtual_reserve()) {
+    arena_reserve = arena_reserve/4;  // be conservative if virtual reserve is not supported (for some embedded systems for example)
+  }
+  arena_reserve = _mi_align_up(arena_reserve, MI_ARENA_BLOCK_SIZE);
+  if (arena_count >= 8 && arena_count <= 128) {
+    arena_reserve = ((size_t)1<<(arena_count/8)) * arena_reserve;  // scale up the arena sizes exponentially
+  }
+  if (arena_reserve < req_size) return false;  // should be able to at least handle the current allocation size
+
+  // commit eagerly?
+  bool arena_commit = false;
+  if (mi_option_get(mi_option_arena_eager_commit) == 2)      { arena_commit = _mi_os_has_overcommit(); }
+  else if (mi_option_get(mi_option_arena_eager_commit) == 1) { arena_commit = true; }
+
+  return (mi_reserve_os_memory_ex(arena_reserve, arena_commit, allow_large, false /* exclusive */, arena_id) == 0);
+}
+
+
+void* _mi_arena_alloc_aligned(size_t size, size_t alignment, size_t align_offset, bool commit, bool allow_large,
+			      mi_arena_id_t req_arena_id, mi_memid_t* memid, mi_os_tld_t* tld)
+{
+  mi_assert_internal(memid != NULL && tld != NULL);
+  mi_assert_internal(size > 0);
+  *memid = _mi_memid_none();
+
+  const int numa_node = _mi_os_numa_node(tld); // current numa node
+
+  // try to allocate in an arena if the alignment is small enough and the object is not too small (as for heap meta data)
+  if (size >= MI_ARENA_MIN_OBJ_SIZE && alignment <= MI_SEGMENT_ALIGN && align_offset == 0) {
+    void* p = mi_arena_try_alloc(numa_node, size, alignment, commit, allow_large, req_arena_id, memid, tld);
+    if (p != NULL) return p;
+
+    // otherwise, try to first eagerly reserve a new arena
+    if (req_arena_id == _mi_arena_id_none()) {
+      mi_arena_id_t arena_id = 0;
+      if (mi_arena_reserve(size, allow_large, req_arena_id, &arena_id)) {
+	// and try allocate in there
+	mi_assert_internal(req_arena_id == _mi_arena_id_none());
+	p = mi_arena_try_alloc_at_id(arena_id, true, numa_node, size, alignment, commit, allow_large, req_arena_id, memid, tld);
+	if (p != NULL) return p;
+      }
+    }
+  }
+
+  // if we cannot use OS allocation, return NULL
+  if (mi_option_is_enabled(mi_option_limit_os_alloc) || req_arena_id != _mi_arena_id_none()) {
+    errno = ENOMEM;
+    return NULL;
+  }
+
+  // finally, fall back to the OS
+  if (align_offset > 0) {
+    return _mi_os_alloc_aligned_at_offset(size, alignment, align_offset, commit, allow_large, memid, tld->stats);
+  }
+  else {
+    return _mi_os_alloc_aligned(size, alignment, commit, allow_large, memid, tld->stats);
+  }
+}
+
+void* _mi_arena_alloc(size_t size, bool commit, bool allow_large, mi_arena_id_t req_arena_id, mi_memid_t* memid, mi_os_tld_t* tld)
+{
+  return _mi_arena_alloc_aligned(size, MI_ARENA_BLOCK_SIZE, 0, commit, allow_large, req_arena_id, memid, tld);
+}
+
+
+void* mi_arena_area(mi_arena_id_t arena_id, size_t* size) {
+  if (size != NULL) *size = 0;
+  size_t arena_index = mi_arena_id_index(arena_id);
+  if (arena_index >= MI_MAX_ARENAS) return NULL;
+  mi_arena_t* arena = mi_atomic_load_ptr_acquire(mi_arena_t, &mi_arenas[arena_index]);
+  if (arena == NULL) return NULL;
+  if (size != NULL) { *size = mi_arena_block_size(arena->block_count); }
+  return arena->start;
+}
+
+
+/* -----------------------------------------------------------
+  Arena purge
+----------------------------------------------------------- */
+
+static long mi_arena_purge_delay(void) {
+  // <0 = no purging allowed, 0=immediate purging, >0=milli-second delay
+  return (mi_option_get(mi_option_purge_delay) * mi_option_get(mi_option_arena_purge_mult));
+}
+
+// reset or decommit in an arena and update the committed/decommit bitmaps
+// assumes we own the area (i.e. blocks_in_use is claimed by us)
+static void mi_arena_purge(mi_arena_t* arena, size_t bitmap_idx, size_t blocks, mi_stats_t* stats) {
+  mi_assert_internal(arena->blocks_committed != NULL);
+  mi_assert_internal(arena->blocks_purge != NULL);
+  mi_assert_internal(!arena->memid.is_pinned);
+  const size_t size = mi_arena_block_size(blocks);
+  void* const p = mi_arena_block_start(arena, bitmap_idx);
+  bool needs_recommit;
+  if (_mi_bitmap_is_claimed_across(arena->blocks_committed, arena->field_count, blocks, bitmap_idx)) {
+    // all blocks are committed, we can purge freely
+    needs_recommit = _mi_os_purge(p, size, stats);
+  }
+  else {
+    // some blocks are not committed -- this can happen when a partially committed block is freed
+    // in `_mi_arena_free` and it is conservatively marked as uncommitted but still scheduled for a purge
+    // we need to ensure we do not try to reset (as that may be invalid for uncommitted memory),
+    // and also undo the decommit stats (as it was already adjusted)
+    mi_assert_internal(mi_option_is_enabled(mi_option_purge_decommits));
+    needs_recommit = _mi_os_purge_ex(p, size, false /* allow reset? */, stats);
+    _mi_stat_increase(&stats->committed, size);
+  }
+
+  // clear the purged blocks
+  _mi_bitmap_unclaim_across(arena->blocks_purge, arena->field_count, blocks, bitmap_idx);
+  // update committed bitmap
+  if (needs_recommit) {
+    _mi_bitmap_unclaim_across(arena->blocks_committed, arena->field_count, blocks, bitmap_idx);
+  }
+}
+
+// Schedule a purge. This is usually delayed to avoid repeated decommit/commit calls.
+// Note: assumes we (still) own the area as we may purge immediately
+static void mi_arena_schedule_purge(mi_arena_t* arena, size_t bitmap_idx, size_t blocks, mi_stats_t* stats) {
+  mi_assert_internal(arena->blocks_purge != NULL);
+  const long delay = mi_arena_purge_delay();
+  if (delay < 0) return;  // is purging allowed at all?
+
+  if (_mi_preloading() || delay == 0) {
+    // decommit directly
+    mi_arena_purge(arena, bitmap_idx, blocks, stats);
+  }
+  else {
+    // schedule decommit
+    mi_msecs_t expire = mi_atomic_loadi64_relaxed(&arena->purge_expire);
+    if (expire != 0) {
+      mi_atomic_addi64_acq_rel(&arena->purge_expire, delay/10);  // add smallish extra delay
+    }
+    else {
+      mi_atomic_storei64_release(&arena->purge_expire, _mi_clock_now() + delay);
+    }
+    _mi_bitmap_claim_across(arena->blocks_purge, arena->field_count, blocks, bitmap_idx, NULL);
+  }
+}
+
+// purge a range of blocks
+// return true if the full range was purged.
+// assumes we own the area (i.e. blocks_in_use is claimed by us)
+static bool mi_arena_purge_range(mi_arena_t* arena, size_t idx, size_t startidx, size_t bitlen, size_t purge, mi_stats_t* stats) {
+  const size_t endidx = startidx + bitlen;
+  size_t bitidx = startidx;
+  bool all_purged = false;
+  while (bitidx < endidx) {
+    // count consequetive ones in the purge mask
+    size_t count = 0;
+    while (bitidx + count < endidx && (purge & ((size_t)1 << (bitidx + count))) != 0) {
+      count++;
+    }
+    if (count > 0) {
+      // found range to be purged
+      const mi_bitmap_index_t range_idx = mi_bitmap_index_create(idx, bitidx);
+      mi_arena_purge(arena, range_idx, count, stats);
+      if (count == bitlen) {
+	all_purged = true;
+      }
+    }
+    bitidx += (count+1); // +1 to skip the zero bit (or end)
+  }
+  return all_purged;
+}
+
+// returns true if anything was purged
+static bool mi_arena_try_purge(mi_arena_t* arena, mi_msecs_t now, bool force, mi_stats_t* stats)
+{
+  if (arena->memid.is_pinned || arena->blocks_purge == NULL) return false;
+  mi_msecs_t expire = mi_atomic_loadi64_relaxed(&arena->purge_expire);
+  if (expire == 0) return false;
+  if (!force && expire > now) return false;
+
+  // reset expire (if not already set concurrently)
+  mi_atomic_casi64_strong_acq_rel(&arena->purge_expire, &expire, 0);
+
+  // potential purges scheduled, walk through the bitmap
+  bool any_purged = false;
+  bool full_purge = true;
+  for (size_t i = 0; i < arena->field_count; i++) {
+    size_t purge = mi_atomic_load_relaxed(&arena->blocks_purge[i]);
+    if (purge != 0) {
+      size_t bitidx = 0;
+      while (bitidx < MI_BITMAP_FIELD_BITS) {
+	// find consequetive range of ones in the purge mask
+	size_t bitlen = 0;
+	while (bitidx + bitlen < MI_BITMAP_FIELD_BITS && (purge & ((size_t)1 << (bitidx + bitlen))) != 0) {
+	  bitlen++;
+	}
+	// try to claim the longest range of corresponding in_use bits
+	const mi_bitmap_index_t bitmap_index = mi_bitmap_index_create(i, bitidx);
+	while( bitlen > 0 ) {
+	  if (_mi_bitmap_try_claim(arena->blocks_inuse, arena->field_count, bitlen, bitmap_index)) {
+	    break;
+	  }
+	  bitlen--;
+	}
+	// actual claimed bits at `in_use`
+	if (bitlen > 0) {
+	  // read purge again now that we have the in_use bits
+	  purge = mi_atomic_load_acquire(&arena->blocks_purge[i]);
+	  if (!mi_arena_purge_range(arena, i, bitidx, bitlen, purge, stats)) {
+	    full_purge = false;
+	  }
+	  any_purged = true;
+	  // release the claimed `in_use` bits again
+	  _mi_bitmap_unclaim(arena->blocks_inuse, arena->field_count, bitlen, bitmap_index);
+	}
+	bitidx += (bitlen+1);  // +1 to skip the zero (or end)
+      } // while bitidx
+    } // purge != 0
+  }
+  // if not fully purged, make sure to purge again in the future
+  if (!full_purge) {
+    const long delay = mi_arena_purge_delay();
+    mi_msecs_t expected = 0;
+    mi_atomic_casi64_strong_acq_rel(&arena->purge_expire,&expected,_mi_clock_now() + delay);
+  }
+  return any_purged;
+}
+
+static void mi_arenas_try_purge( bool force, bool visit_all, mi_stats_t* stats ) {
+  if (_mi_preloading() || mi_arena_purge_delay() <= 0) return;  // nothing will be scheduled
+
+  const size_t max_arena = mi_atomic_load_acquire(&mi_arena_count);
+  if (max_arena == 0) return;
+
+  // allow only one thread to purge at a time
+  static mi_atomic_guard_t purge_guard;
+  mi_atomic_guard(&purge_guard)
+  {
+    mi_msecs_t now = _mi_clock_now();
+    size_t max_purge_count = (visit_all ? max_arena : 1);
+    for (size_t i = 0; i < max_arena; i++) {
+      mi_arena_t* arena = mi_atomic_load_ptr_acquire(mi_arena_t, &mi_arenas[i]);
+      if (arena != NULL) {
+	if (mi_arena_try_purge(arena, now, force, stats)) {
+	  if (max_purge_count <= 1) break;
+	  max_purge_count--;
+	}
+      }
+    }
+  }
+}
+
+
+/* -----------------------------------------------------------
+  Arena free
+----------------------------------------------------------- */
+
+void _mi_arena_free(void* p, size_t size, size_t committed_size, mi_memid_t memid, mi_stats_t* stats) {
+  mi_assert_internal(size > 0 && stats != NULL);
+  mi_assert_internal(committed_size <= size);
+  if (p==NULL) return;
+  if (size==0) return;
+  const bool all_committed = (committed_size == size);
+
+  if (mi_memkind_is_os(memid.memkind)) {
+    // was a direct OS allocation, pass through
+    if (!all_committed && committed_size > 0) {
+      // if partially committed, adjust the committed stats (as `_mi_os_free` will increase decommit by the full size)
+      _mi_stat_decrease(&stats->committed, committed_size);
+    }
+    _mi_os_free(p, size, memid, stats);
+  }
+  else if (memid.memkind == MI_MEM_ARENA) {
+    // allocated in an arena
+    size_t arena_idx;
+    size_t bitmap_idx;
+    mi_arena_memid_indices(memid, &arena_idx, &bitmap_idx);
+    mi_assert_internal(arena_idx < MI_MAX_ARENAS);
+    mi_arena_t* arena = mi_atomic_load_ptr_acquire(mi_arena_t,&mi_arenas[arena_idx]);
+    mi_assert_internal(arena != NULL);
+    const size_t blocks = mi_block_count_of_size(size);
+
+    // checks
+    if (arena == NULL) {
+      _mi_error_message(EINVAL, "trying to free from non-existent arena: %p, size %zu, memid: 0x%zx\n", p, size, memid);
+      return;
+    }
+    mi_assert_internal(arena->field_count > mi_bitmap_index_field(bitmap_idx));
+    if (arena->field_count <= mi_bitmap_index_field(bitmap_idx)) {
+      _mi_error_message(EINVAL, "trying to free from non-existent arena block: %p, size %zu, memid: 0x%zx\n", p, size, memid);
+      return;
+    }
+
+    // need to set all memory to undefined as some parts may still be marked as no_access (like padding etc.)
+    mi_track_mem_undefined(p,size);
+
+    // potentially decommit
+    if (arena->memid.is_pinned || arena->blocks_committed == NULL) {
+      mi_assert_internal(all_committed);
+    }
+    else {
+      mi_assert_internal(arena->blocks_committed != NULL);
+      mi_assert_internal(arena->blocks_purge != NULL);
+
+      if (!all_committed) {
+	// mark the entire range as no longer committed (so we recommit the full range when re-using)
+	_mi_bitmap_unclaim_across(arena->blocks_committed, arena->field_count, blocks, bitmap_idx);
+	mi_track_mem_noaccess(p,size);
+	if (committed_size > 0) {
+	  // if partially committed, adjust the committed stats (is it will be recommitted when re-using)
+	  // in the delayed purge, we now need to not count a decommit if the range is not marked as committed.
+	  _mi_stat_decrease(&stats->committed, committed_size);
+	}
+	// note: if not all committed, it may be that the purge will reset/decommit the entire range
+	// that contains already decommitted parts. Since purge consistently uses reset or decommit that
+	// works (as we should never reset decommitted parts).
+      }
+      // (delay) purge the entire range
+      mi_arena_schedule_purge(arena, bitmap_idx, blocks, stats);
+    }
+
+    // and make it available to others again
+    bool all_inuse = _mi_bitmap_unclaim_across(arena->blocks_inuse, arena->field_count, blocks, bitmap_idx);
+    if (!all_inuse) {
+      _mi_error_message(EAGAIN, "trying to free an already freed arena block: %p, size %zu\n", p, size);
+      return;
+    };
+  }
+  else {
+    // arena was none, external, or static; nothing to do
+    mi_assert_internal(memid.memkind < MI_MEM_OS);
+  }
+
+  // purge expired decommits
+  mi_arenas_try_purge(false, false, stats);
+}
+
+// destroy owned arenas; this is unsafe and should only be done using `mi_option_destroy_on_exit`
+// for dynamic libraries that are unloaded and need to release all their allocated memory.
+static void mi_arenas_unsafe_destroy(void) {
+  const size_t max_arena = mi_atomic_load_relaxed(&mi_arena_count);
+  size_t new_max_arena = 0;
+  for (size_t i = 0; i < max_arena; i++) {
+    mi_arena_t* arena = mi_atomic_load_ptr_acquire(mi_arena_t, &mi_arenas[i]);
+    if (arena != NULL) {
+      if (arena->start != NULL && mi_memkind_is_os(arena->memid.memkind)) {
+	mi_atomic_store_ptr_release(mi_arena_t, &mi_arenas[i], NULL);
+	_mi_os_free(arena->start, mi_arena_size(arena), arena->memid, &_mi_stats_main);
+      }
+      else {
+	new_max_arena = i;
+      }
+      mi_arena_meta_free(arena, arena->meta_memid, arena->meta_size, &_mi_stats_main);
+    }
+  }
+
+  // try to lower the max arena.
+  size_t expected = max_arena;
+  mi_atomic_cas_strong_acq_rel(&mi_arena_count, &expected, new_max_arena);
+}
+
+// Purge the arenas; if `force_purge` is true, amenable parts are purged even if not yet expired
+void _mi_arena_collect(bool force_purge, mi_stats_t* stats) {
+  mi_arenas_try_purge(force_purge, true /* visit all */, stats);
+}
+
+// destroy owned arenas; this is unsafe and should only be done using `mi_option_destroy_on_exit`
+// for dynamic libraries that are unloaded and need to release all their allocated memory.
+void _mi_arena_unsafe_destroy_all(mi_stats_t* stats) {
+  mi_arenas_unsafe_destroy();
+  _mi_arena_collect(true /* force purge */, stats);  // purge non-owned arenas
+}
+
+// Is a pointer inside any of our arenas?
+bool _mi_arena_contains(const void* p) {
+  const size_t max_arena = mi_atomic_load_relaxed(&mi_arena_count);
+  for (size_t i = 0; i < max_arena; i++) {
+    mi_arena_t* arena = mi_atomic_load_ptr_acquire(mi_arena_t, &mi_arenas[i]);
+    if (arena != NULL && arena->start <= (const uint8_t*)p && arena->start + mi_arena_block_size(arena->block_count) > (const uint8_t*)p) {
+      return true;
+    }
+  }
+  return false;
+}
+
+
+/* -----------------------------------------------------------
+  Add an arena.
+----------------------------------------------------------- */
+
+static bool mi_arena_add(mi_arena_t* arena, mi_arena_id_t* arena_id) {
+  mi_assert_internal(arena != NULL);
+  mi_assert_internal((uintptr_t)mi_atomic_load_ptr_relaxed(uint8_t,&arena->start) % MI_SEGMENT_ALIGN == 0);
+  mi_assert_internal(arena->block_count > 0);
+  if (arena_id != NULL) { *arena_id = -1; }
+
+  size_t i = mi_atomic_increment_acq_rel(&mi_arena_count);
+  if (i >= MI_MAX_ARENAS) {
+    mi_atomic_decrement_acq_rel(&mi_arena_count);
+    return false;
+  }
+  arena->id = mi_arena_id_create(i);
+  mi_atomic_store_ptr_release(mi_arena_t,&mi_arenas[i], arena);
+  if (arena_id != NULL) { *arena_id = arena->id; }
+  return true;
+}
+
+static bool mi_manage_os_memory_ex2(void* start, size_t size, bool is_large, int numa_node, bool exclusive, mi_memid_t memid, mi_arena_id_t* arena_id) mi_attr_noexcept
+{
+  if (arena_id != NULL) *arena_id = _mi_arena_id_none();
+  if (size < MI_ARENA_BLOCK_SIZE) return false;
+
+  if (is_large) {
+    mi_assert_internal(memid.initially_committed && memid.is_pinned);
+  }
+
+  const size_t bcount = size / MI_ARENA_BLOCK_SIZE;
+  const size_t fields = _mi_divide_up(bcount, MI_BITMAP_FIELD_BITS);
+  const size_t bitmaps = (memid.is_pinned ? 2 : 4);
+  const size_t asize  = sizeof(mi_arena_t) + (bitmaps*fields*sizeof(mi_bitmap_field_t));
+  mi_memid_t meta_memid;
+  mi_arena_t* arena   = (mi_arena_t*)mi_arena_meta_zalloc(asize, &meta_memid, &_mi_stats_main); // TODO: can we avoid allocating from the OS?
+  if (arena == NULL) return false;
+
+  // already zero'd due to os_alloc
+  // _mi_memzero(arena, asize);
+  arena->id = _mi_arena_id_none();
+  arena->memid = memid;
+  arena->exclusive = exclusive;
+  arena->meta_size = asize;
+  arena->meta_memid = meta_memid;
+  arena->block_count = bcount;
+  arena->field_count = fields;
+  arena->start = (uint8_t*)start;
+  arena->numa_node    = numa_node; // TODO: or get the current numa node if -1? (now it allows anyone to allocate on -1)
+  arena->is_large     = is_large;
+  arena->purge_expire = 0;
+  arena->search_idx   = 0;
+  arena->blocks_dirty = &arena->blocks_inuse[fields]; // just after inuse bitmap
+  arena->blocks_committed = (arena->memid.is_pinned ? NULL : &arena->blocks_inuse[2*fields]); // just after dirty bitmap
+  arena->blocks_purge  = (arena->memid.is_pinned ? NULL : &arena->blocks_inuse[3*fields]); // just after committed bitmap
+  // initialize committed bitmap?
+  if (arena->blocks_committed != NULL && arena->memid.initially_committed) {
+    memset((void*)arena->blocks_committed, 0xFF, fields*sizeof(mi_bitmap_field_t)); // cast to void* to avoid atomic warning
+  }
+
+  // and claim leftover blocks if needed (so we never allocate there)
+  ptrdiff_t post = (fields * MI_BITMAP_FIELD_BITS) - bcount;
+  mi_assert_internal(post >= 0);
+  if (post > 0) {
+    // don't use leftover bits at the end
+    mi_bitmap_index_t postidx = mi_bitmap_index_create(fields - 1, MI_BITMAP_FIELD_BITS - post);
+    _mi_bitmap_claim(arena->blocks_inuse, fields, post, postidx, NULL);
+  }
+  return mi_arena_add(arena, arena_id);
+
+}
+
+bool mi_manage_os_memory_ex(void* start, size_t size, bool is_committed, bool is_large, bool is_zero, int numa_node, bool exclusive, mi_arena_id_t* arena_id) mi_attr_noexcept {
+  mi_memid_t memid = _mi_memid_create(MI_MEM_EXTERNAL);
+  memid.initially_committed = is_committed;
+  memid.initially_zero = is_zero;
+  memid.is_pinned = is_large;
+  return mi_manage_os_memory_ex2(start,size,is_large,numa_node,exclusive,memid, arena_id);
+}
+
+// Reserve a range of regular OS memory
+int mi_reserve_os_memory_ex(size_t size, bool commit, bool allow_large, bool exclusive, mi_arena_id_t* arena_id) mi_attr_noexcept {
+  if (arena_id != NULL) *arena_id = _mi_arena_id_none();
+  size = _mi_align_up(size, MI_ARENA_BLOCK_SIZE); // at least one block
+  mi_memid_t memid;
+  void* start = _mi_os_alloc_aligned(size, MI_SEGMENT_ALIGN, commit, allow_large, &memid, &_mi_stats_main);
+  if (start == NULL) return ENOMEM;
+  const bool is_large = memid.is_pinned; // todo: use separate is_large field?
+  if (!mi_manage_os_memory_ex2(start, size, is_large, -1 /* numa node */, exclusive, memid, arena_id)) {
+    _mi_os_free_ex(start, size, commit, memid, &_mi_stats_main);
+    _mi_verbose_message("failed to reserve %zu k memory\n", _mi_divide_up(size, 1024));
+    return ENOMEM;
+  }
+  _mi_verbose_message("reserved %zu KiB memory%s\n", _mi_divide_up(size, 1024), is_large ? " (in large os pages)" : "");
+  return 0;
+}
+
+
+// Manage a range of regular OS memory
+bool mi_manage_os_memory(void* start, size_t size, bool is_committed, bool is_large, bool is_zero, int numa_node) mi_attr_noexcept {
+  return mi_manage_os_memory_ex(start, size, is_committed, is_large, is_zero, numa_node, false /* exclusive? */, NULL);
+}
+
+// Reserve a range of regular OS memory
+int mi_reserve_os_memory(size_t size, bool commit, bool allow_large) mi_attr_noexcept {
+  return mi_reserve_os_memory_ex(size, commit, allow_large, false, NULL);
+}
+
+
+/* -----------------------------------------------------------
+  Debugging
+----------------------------------------------------------- */
+
+static size_t mi_debug_show_bitmap(const char* prefix, mi_bitmap_field_t* fields, size_t field_count ) {
+  size_t inuse_count = 0;
+  for (size_t i = 0; i < field_count; i++) {
+    char buf[MI_BITMAP_FIELD_BITS + 1];
+    uintptr_t field = mi_atomic_load_relaxed(&fields[i]);
+    for (size_t bit = 0; bit < MI_BITMAP_FIELD_BITS; bit++) {
+      bool inuse = ((((uintptr_t)1 << bit) & field) != 0);
+      if (inuse) inuse_count++;
+      buf[MI_BITMAP_FIELD_BITS - 1 - bit] = (inuse ? 'x' : '.');
+    }
+    buf[MI_BITMAP_FIELD_BITS] = 0;
+    _mi_verbose_message("%s%s\n", prefix, buf);
+  }
+  return inuse_count;
+}
+
+void mi_debug_show_arenas(void) mi_attr_noexcept {
+  size_t max_arenas = mi_atomic_load_relaxed(&mi_arena_count);
+  for (size_t i = 0; i < max_arenas; i++) {
+    mi_arena_t* arena = mi_atomic_load_ptr_relaxed(mi_arena_t, &mi_arenas[i]);
+    if (arena == NULL) break;
+    size_t inuse_count = 0;
+    _mi_verbose_message("arena %zu: %zu blocks with %zu fields\n", i, arena->block_count, arena->field_count);
+    inuse_count += mi_debug_show_bitmap("  ", arena->blocks_inuse, arena->field_count);
+    _mi_verbose_message("  blocks in use ('x'): %zu\n", inuse_count);
+  }
+}
+
+
+/* -----------------------------------------------------------
+  Reserve a huge page arena.
+----------------------------------------------------------- */
+// reserve at a specific numa node
+int mi_reserve_huge_os_pages_at_ex(size_t pages, int numa_node, size_t timeout_msecs, bool exclusive, mi_arena_id_t* arena_id) mi_attr_noexcept {
+  if (arena_id != NULL) *arena_id = -1;
+  if (pages==0) return 0;
+  if (numa_node < -1) numa_node = -1;
+  if (numa_node >= 0) numa_node = numa_node % _mi_os_numa_node_count();
+  size_t hsize = 0;
+  size_t pages_reserved = 0;
+  mi_memid_t memid;
+  void* p = _mi_os_alloc_huge_os_pages(pages, numa_node, timeout_msecs, &pages_reserved, &hsize, &memid);
+  if (p==NULL || pages_reserved==0) {
+    _mi_warning_message("failed to reserve %zu GiB huge pages\n", pages);
+    return ENOMEM;
+  }
+  _mi_verbose_message("numa node %i: reserved %zu GiB huge pages (of the %zu GiB requested)\n", numa_node, pages_reserved, pages);
+
+  if (!mi_manage_os_memory_ex2(p, hsize, true, numa_node, exclusive, memid, arena_id)) {
+    _mi_os_free(p, hsize, memid, &_mi_stats_main);
+    return ENOMEM;
+  }
+  return 0;
+}
+
+int mi_reserve_huge_os_pages_at(size_t pages, int numa_node, size_t timeout_msecs) mi_attr_noexcept {
+  return mi_reserve_huge_os_pages_at_ex(pages, numa_node, timeout_msecs, false, NULL);
+}
+
+// reserve huge pages evenly among the given number of numa nodes (or use the available ones as detected)
+int mi_reserve_huge_os_pages_interleave(size_t pages, size_t numa_nodes, size_t timeout_msecs) mi_attr_noexcept {
+  if (pages == 0) return 0;
+
+  // pages per numa node
+  size_t numa_count = (numa_nodes > 0 ? numa_nodes : _mi_os_numa_node_count());
+  if (numa_count <= 0) numa_count = 1;
+  const size_t pages_per = pages / numa_count;
+  const size_t pages_mod = pages % numa_count;
+  const size_t timeout_per = (timeout_msecs==0 ? 0 : (timeout_msecs / numa_count) + 50);
+
+  // reserve evenly among numa nodes
+  for (size_t numa_node = 0; numa_node < numa_count && pages > 0; numa_node++) {
+    size_t node_pages = pages_per;  // can be 0
+    if (numa_node < pages_mod) node_pages++;
+    int err = mi_reserve_huge_os_pages_at(node_pages, (int)numa_node, timeout_per);
+    if (err) return err;
+    if (pages < node_pages) {
+      pages = 0;
+    }
+    else {
+      pages -= node_pages;
+    }
+  }
+
+  return 0;
+}
+
+int mi_reserve_huge_os_pages(size_t pages, double max_secs, size_t* pages_reserved) mi_attr_noexcept {
+  MI_UNUSED(max_secs);
+  _mi_warning_message("mi_reserve_huge_os_pages is deprecated: use mi_reserve_huge_os_pages_interleave/at instead\n");
+  if (pages_reserved != NULL) *pages_reserved = 0;
+  int err = mi_reserve_huge_os_pages_interleave(pages, 0, (size_t)(max_secs * 1000.0));
+  if (err==0 && pages_reserved!=NULL) *pages_reserved = pages;
+  return err;
+}
diff --git a/compat/mimalloc/bitmap.c b/compat/mimalloc/bitmap.c
new file mode 100644
index 00000000000000..878f0ab3250a47
--- /dev/null
+++ b/compat/mimalloc/bitmap.c
@@ -0,0 +1,432 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2019-2023 Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+
+/* ----------------------------------------------------------------------------
+Concurrent bitmap that can set/reset sequences of bits atomically,
+represeted as an array of fields where each field is a machine word (`size_t`)
+
+There are two api's; the standard one cannot have sequences that cross
+between the bitmap fields (and a sequence must be <= MI_BITMAP_FIELD_BITS).
+
+The `_across` postfixed functions do allow sequences that can cross over
+between the fields. (This is used in arena allocation)
+---------------------------------------------------------------------------- */
+
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "bitmap.h"
+
+/* -----------------------------------------------------------
+  Bitmap definition
+----------------------------------------------------------- */
+
+// The bit mask for a given number of blocks at a specified bit index.
+static inline size_t mi_bitmap_mask_(size_t count, size_t bitidx) {
+  mi_assert_internal(count + bitidx <= MI_BITMAP_FIELD_BITS);
+  mi_assert_internal(count > 0);
+  if (count >= MI_BITMAP_FIELD_BITS) return MI_BITMAP_FIELD_FULL;
+  if (count == 0) return 0;
+  return ((((size_t)1 << count) - 1) << bitidx);
+}
+
+
+/* -----------------------------------------------------------
+  Claim a bit sequence atomically
+----------------------------------------------------------- */
+
+// Try to atomically claim a sequence of `count` bits in a single
+// field at `idx` in `bitmap`. Returns `true` on success.
+inline bool _mi_bitmap_try_find_claim_field(mi_bitmap_t bitmap, size_t idx, const size_t count, mi_bitmap_index_t* bitmap_idx)
+{
+  mi_assert_internal(bitmap_idx != NULL);
+  mi_assert_internal(count <= MI_BITMAP_FIELD_BITS);
+  mi_assert_internal(count > 0);
+  mi_bitmap_field_t* field = &bitmap[idx];
+  size_t map  = mi_atomic_load_relaxed(field);
+  if (map==MI_BITMAP_FIELD_FULL) return false; // short cut
+
+  // search for 0-bit sequence of length count
+  const size_t mask = mi_bitmap_mask_(count, 0);
+  const size_t bitidx_max = MI_BITMAP_FIELD_BITS - count;
+
+#ifdef MI_HAVE_FAST_BITSCAN
+  size_t bitidx = mi_ctz(~map);    // quickly find the first zero bit if possible
+#else
+  size_t bitidx = 0;               // otherwise start at 0
+#endif
+  size_t m = (mask << bitidx);     // invariant: m == mask shifted by bitidx
+
+  // scan linearly for a free range of zero bits
+  while (bitidx <= bitidx_max) {
+    const size_t mapm = (map & m);
+    if (mapm == 0) {  // are the mask bits free at bitidx?
+      mi_assert_internal((m >> bitidx) == mask); // no overflow?
+      const size_t newmap = (map | m);
+      mi_assert_internal((newmap^map) >> bitidx == mask);
+      if (!mi_atomic_cas_strong_acq_rel(field, &map, newmap)) {  // TODO: use weak cas here?
+	// no success, another thread claimed concurrently.. keep going (with updated `map`)
+	continue;
+      }
+      else {
+	// success, we claimed the bits!
+	*bitmap_idx = mi_bitmap_index_create(idx, bitidx);
+	return true;
+      }
+    }
+    else {
+      // on to the next bit range
+#ifdef MI_HAVE_FAST_BITSCAN
+      mi_assert_internal(mapm != 0);
+      const size_t shift = (count == 1 ? 1 : (MI_INTPTR_BITS - mi_clz(mapm) - bitidx));
+      mi_assert_internal(shift > 0 && shift <= count);
+#else
+      const size_t shift = 1;
+#endif
+      bitidx += shift;
+      m <<= shift;
+    }
+  }
+  // no bits found
+  return false;
+}
+
+// Find `count` bits of 0 and set them to 1 atomically; returns `true` on success.
+// Starts at idx, and wraps around to search in all `bitmap_fields` fields.
+// `count` can be at most MI_BITMAP_FIELD_BITS and will never cross fields.
+bool _mi_bitmap_try_find_from_claim(mi_bitmap_t bitmap, const size_t bitmap_fields, const size_t start_field_idx, const size_t count, mi_bitmap_index_t* bitmap_idx) {
+  size_t idx = start_field_idx;
+  for (size_t visited = 0; visited < bitmap_fields; visited++, idx++) {
+    if (idx >= bitmap_fields) { idx = 0; } // wrap
+    if (_mi_bitmap_try_find_claim_field(bitmap, idx, count, bitmap_idx)) {
+      return true;
+    }
+  }
+  return false;
+}
+
+// Like _mi_bitmap_try_find_from_claim but with an extra predicate that must be fullfilled
+bool _mi_bitmap_try_find_from_claim_pred(mi_bitmap_t bitmap, const size_t bitmap_fields,
+	    const size_t start_field_idx, const size_t count,
+	    mi_bitmap_pred_fun_t pred_fun, void* pred_arg,
+	    mi_bitmap_index_t* bitmap_idx) {
+  size_t idx = start_field_idx;
+  for (size_t visited = 0; visited < bitmap_fields; visited++, idx++) {
+    if (idx >= bitmap_fields) idx = 0; // wrap
+    if (_mi_bitmap_try_find_claim_field(bitmap, idx, count, bitmap_idx)) {
+      if (pred_fun == NULL || pred_fun(*bitmap_idx, pred_arg)) {
+	return true;
+      }
+      // predicate returned false, unclaim and look further
+      _mi_bitmap_unclaim(bitmap, bitmap_fields, count, *bitmap_idx);
+    }
+  }
+  return false;
+}
+
+// Set `count` bits at `bitmap_idx` to 0 atomically
+// Returns `true` if all `count` bits were 1 previously.
+bool _mi_bitmap_unclaim(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
+  const size_t idx = mi_bitmap_index_field(bitmap_idx);
+  const size_t bitidx = mi_bitmap_index_bit_in_field(bitmap_idx);
+  const size_t mask = mi_bitmap_mask_(count, bitidx);
+  mi_assert_internal(bitmap_fields > idx); MI_UNUSED(bitmap_fields);
+  // mi_assert_internal((bitmap[idx] & mask) == mask);
+  const size_t prev = mi_atomic_and_acq_rel(&bitmap[idx], ~mask);
+  return ((prev & mask) == mask);
+}
+
+
+// Set `count` bits at `bitmap_idx` to 1 atomically
+// Returns `true` if all `count` bits were 0 previously. `any_zero` is `true` if there was at least one zero bit.
+bool _mi_bitmap_claim(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* any_zero) {
+  const size_t idx = mi_bitmap_index_field(bitmap_idx);
+  const size_t bitidx = mi_bitmap_index_bit_in_field(bitmap_idx);
+  const size_t mask = mi_bitmap_mask_(count, bitidx);
+  mi_assert_internal(bitmap_fields > idx); MI_UNUSED(bitmap_fields);
+  //mi_assert_internal(any_zero != NULL || (bitmap[idx] & mask) == 0);
+  size_t prev = mi_atomic_or_acq_rel(&bitmap[idx], mask);
+  if (any_zero != NULL) { *any_zero = ((prev & mask) != mask); }
+  return ((prev & mask) == 0);
+}
+
+// Returns `true` if all `count` bits were 1. `any_ones` is `true` if there was at least one bit set to one.
+static bool mi_bitmap_is_claimedx(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* any_ones) {
+  const size_t idx = mi_bitmap_index_field(bitmap_idx);
+  const size_t bitidx = mi_bitmap_index_bit_in_field(bitmap_idx);
+  const size_t mask = mi_bitmap_mask_(count, bitidx);
+  mi_assert_internal(bitmap_fields > idx); MI_UNUSED(bitmap_fields);
+  const size_t field = mi_atomic_load_relaxed(&bitmap[idx]);
+  if (any_ones != NULL) { *any_ones = ((field & mask) != 0); }
+  return ((field & mask) == mask);
+}
+
+// Try to set `count` bits at `bitmap_idx` from 0 to 1 atomically.
+// Returns `true` if successful when all previous `count` bits were 0.
+bool _mi_bitmap_try_claim(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
+  const size_t idx = mi_bitmap_index_field(bitmap_idx);
+  const size_t bitidx = mi_bitmap_index_bit_in_field(bitmap_idx);
+  const size_t mask = mi_bitmap_mask_(count, bitidx);
+  mi_assert_internal(bitmap_fields > idx); MI_UNUSED(bitmap_fields);
+  size_t expected = mi_atomic_load_relaxed(&bitmap[idx]);
+  do  {
+    if ((expected & mask) != 0) return false;
+  }
+  while (!mi_atomic_cas_strong_acq_rel(&bitmap[idx], &expected, expected | mask));
+  mi_assert_internal((expected & mask) == 0);
+  return true;
+}
+
+
+bool _mi_bitmap_is_claimed(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
+  return mi_bitmap_is_claimedx(bitmap, bitmap_fields, count, bitmap_idx, NULL);
+}
+
+bool _mi_bitmap_is_any_claimed(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
+  bool any_ones;
+  mi_bitmap_is_claimedx(bitmap, bitmap_fields, count, bitmap_idx, &any_ones);
+  return any_ones;
+}
+
+
+//--------------------------------------------------------------------------
+// the `_across` functions work on bitmaps where sequences can cross over
+// between the fields. This is used in arena allocation
+//--------------------------------------------------------------------------
+
+// Try to atomically claim a sequence of `count` bits starting from the field
+// at `idx` in `bitmap` and crossing into subsequent fields. Returns `true` on success.
+// Only needs to consider crossing into the next fields (see `mi_bitmap_try_find_from_claim_across`)
+static bool mi_bitmap_try_find_claim_field_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t idx, const size_t count, const size_t retries, mi_bitmap_index_t* bitmap_idx)
+{
+  mi_assert_internal(bitmap_idx != NULL);
+
+  // check initial trailing zeros
+  mi_bitmap_field_t* field = &bitmap[idx];
+  size_t map = mi_atomic_load_relaxed(field);
+  const size_t initial = mi_clz(map);  // count of initial zeros starting at idx
+  mi_assert_internal(initial <= MI_BITMAP_FIELD_BITS);
+  if (initial == 0)     return false;
+  if (initial >= count) return _mi_bitmap_try_find_claim_field(bitmap, idx, count, bitmap_idx);    // no need to cross fields (this case won't happen for us)
+  if (_mi_divide_up(count - initial, MI_BITMAP_FIELD_BITS) >= (bitmap_fields - idx)) return false; // not enough entries
+
+  // scan ahead
+  size_t found = initial;
+  size_t mask = 0;     // mask bits for the final field
+  while(found < count) {
+    field++;
+    map = mi_atomic_load_relaxed(field);
+    const size_t mask_bits = (found + MI_BITMAP_FIELD_BITS <= count ? MI_BITMAP_FIELD_BITS : (count - found));
+    mi_assert_internal(mask_bits > 0 && mask_bits <= MI_BITMAP_FIELD_BITS);
+    mask = mi_bitmap_mask_(mask_bits, 0);
+    if ((map & mask) != 0) return false;  // some part is already claimed
+    found += mask_bits;
+  }
+  mi_assert_internal(field < &bitmap[bitmap_fields]);
+
+  // we found a range of contiguous zeros up to the final field; mask contains mask in the final field
+  // now try to claim the range atomically
+  mi_bitmap_field_t* const final_field = field;
+  const size_t final_mask = mask;
+  mi_bitmap_field_t* const initial_field = &bitmap[idx];
+  const size_t initial_idx = MI_BITMAP_FIELD_BITS - initial;
+  const size_t initial_mask = mi_bitmap_mask_(initial, initial_idx);
+
+  // initial field
+  size_t newmap;
+  field = initial_field;
+  map = mi_atomic_load_relaxed(field);
+  do {
+    newmap = (map | initial_mask);
+    if ((map & initial_mask) != 0) { goto rollback; };
+  } while (!mi_atomic_cas_strong_acq_rel(field, &map, newmap));
+
+  // intermediate fields
+  while (++field < final_field) {
+    newmap = MI_BITMAP_FIELD_FULL;
+    map = 0;
+    if (!mi_atomic_cas_strong_acq_rel(field, &map, newmap)) { goto rollback; }
+  }
+
+  // final field
+  mi_assert_internal(field == final_field);
+  map = mi_atomic_load_relaxed(field);
+  do {
+    newmap = (map | final_mask);
+    if ((map & final_mask) != 0) { goto rollback; }
+  } while (!mi_atomic_cas_strong_acq_rel(field, &map, newmap));
+
+  // claimed!
+  *bitmap_idx = mi_bitmap_index_create(idx, initial_idx);
+  return true;
+
+rollback:
+  // roll back intermediate fields
+  // (we just failed to claim `field` so decrement first)
+  while (--field > initial_field) {
+    newmap = 0;
+    map = MI_BITMAP_FIELD_FULL;
+    mi_assert_internal(mi_atomic_load_relaxed(field) == map);
+    mi_atomic_store_release(field, newmap);
+  }
+  if (field == initial_field) {               // (if we failed on the initial field, `field + 1 == initial_field`)
+    map = mi_atomic_load_relaxed(field);
+    do {
+      mi_assert_internal((map & initial_mask) == initial_mask);
+      newmap = (map & ~initial_mask);
+    } while (!mi_atomic_cas_strong_acq_rel(field, &map, newmap));
+  }
+  // retry? (we make a recursive call instead of goto to be able to use const declarations)
+  if (retries <= 2) {
+    return mi_bitmap_try_find_claim_field_across(bitmap, bitmap_fields, idx, count, retries+1, bitmap_idx);
+  }
+  else {
+    return false;
+  }
+}
+
+
+// Find `count` bits of zeros and set them to 1 atomically; returns `true` on success.
+// Starts at idx, and wraps around to search in all `bitmap_fields` fields.
+bool _mi_bitmap_try_find_from_claim_across(mi_bitmap_t bitmap, const size_t bitmap_fields, const size_t start_field_idx, const size_t count, mi_bitmap_index_t* bitmap_idx) {
+  mi_assert_internal(count > 0);
+  if (count <= 2) {
+    // we don't bother with crossover fields for small counts
+    return _mi_bitmap_try_find_from_claim(bitmap, bitmap_fields, start_field_idx, count, bitmap_idx);
+  }
+
+  // visit the fields
+  size_t idx = start_field_idx;
+  for (size_t visited = 0; visited < bitmap_fields; visited++, idx++) {
+    if (idx >= bitmap_fields) { idx = 0; } // wrap
+    // first try to claim inside a field
+    if (count <= MI_BITMAP_FIELD_BITS) {
+      if (_mi_bitmap_try_find_claim_field(bitmap, idx, count, bitmap_idx)) {
+	return true;
+      }
+    }
+    // if that fails, then try to claim across fields
+    if (mi_bitmap_try_find_claim_field_across(bitmap, bitmap_fields, idx, count, 0, bitmap_idx)) {
+      return true;
+    }
+  }
+  return false;
+}
+
+// Helper for masks across fields; returns the mid count, post_mask may be 0
+static size_t mi_bitmap_mask_across(mi_bitmap_index_t bitmap_idx, size_t bitmap_fields, size_t count, size_t* pre_mask, size_t* mid_mask, size_t* post_mask) {
+  MI_UNUSED(bitmap_fields);
+  const size_t bitidx = mi_bitmap_index_bit_in_field(bitmap_idx);
+  if mi_likely(bitidx + count <= MI_BITMAP_FIELD_BITS) {
+    *pre_mask = mi_bitmap_mask_(count, bitidx);
+    *mid_mask = 0;
+    *post_mask = 0;
+    mi_assert_internal(mi_bitmap_index_field(bitmap_idx) < bitmap_fields);
+    return 0;
+  }
+  else {
+    const size_t pre_bits = MI_BITMAP_FIELD_BITS - bitidx;
+    mi_assert_internal(pre_bits < count);
+    *pre_mask = mi_bitmap_mask_(pre_bits, bitidx);
+    count -= pre_bits;
+    const size_t mid_count = (count / MI_BITMAP_FIELD_BITS);
+    *mid_mask = MI_BITMAP_FIELD_FULL;
+    count %= MI_BITMAP_FIELD_BITS;
+    *post_mask = (count==0 ? 0 : mi_bitmap_mask_(count, 0));
+    mi_assert_internal(mi_bitmap_index_field(bitmap_idx) + mid_count + (count==0 ? 0 : 1) < bitmap_fields);
+    return mid_count;
+  }
+}
+
+// Set `count` bits at `bitmap_idx` to 0 atomically
+// Returns `true` if all `count` bits were 1 previously.
+bool _mi_bitmap_unclaim_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
+  size_t idx = mi_bitmap_index_field(bitmap_idx);
+  size_t pre_mask;
+  size_t mid_mask;
+  size_t post_mask;
+  size_t mid_count = mi_bitmap_mask_across(bitmap_idx, bitmap_fields, count, &pre_mask, &mid_mask, &post_mask);
+  bool all_one = true;
+  mi_bitmap_field_t* field = &bitmap[idx];
+  size_t prev = mi_atomic_and_acq_rel(field++, ~pre_mask);   // clear first part
+  if ((prev & pre_mask) != pre_mask) all_one = false;
+  while(mid_count-- > 0) {
+    prev = mi_atomic_and_acq_rel(field++, ~mid_mask);        // clear mid part
+    if ((prev & mid_mask) != mid_mask) all_one = false;
+  }
+  if (post_mask!=0) {
+    prev = mi_atomic_and_acq_rel(field, ~post_mask);         // clear end part
+    if ((prev & post_mask) != post_mask) all_one = false;
+  }
+  return all_one;
+}
+
+// Set `count` bits at `bitmap_idx` to 1 atomically
+// Returns `true` if all `count` bits were 0 previously. `any_zero` is `true` if there was at least one zero bit.
+bool _mi_bitmap_claim_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* pany_zero) {
+  size_t idx = mi_bitmap_index_field(bitmap_idx);
+  size_t pre_mask;
+  size_t mid_mask;
+  size_t post_mask;
+  size_t mid_count = mi_bitmap_mask_across(bitmap_idx, bitmap_fields, count, &pre_mask, &mid_mask, &post_mask);
+  bool all_zero = true;
+  bool any_zero = false;
+  _Atomic(size_t)*field = &bitmap[idx];
+  size_t prev = mi_atomic_or_acq_rel(field++, pre_mask);
+  if ((prev & pre_mask) != 0) all_zero = false;
+  if ((prev & pre_mask) != pre_mask) any_zero = true;
+  while (mid_count-- > 0) {
+    prev = mi_atomic_or_acq_rel(field++, mid_mask);
+    if ((prev & mid_mask) != 0) all_zero = false;
+    if ((prev & mid_mask) != mid_mask) any_zero = true;
+  }
+  if (post_mask!=0) {
+    prev = mi_atomic_or_acq_rel(field, post_mask);
+    if ((prev & post_mask) != 0) all_zero = false;
+    if ((prev & post_mask) != post_mask) any_zero = true;
+  }
+  if (pany_zero != NULL) { *pany_zero = any_zero; }
+  return all_zero;
+}
+
+
+// Returns `true` if all `count` bits were 1.
+// `any_ones` is `true` if there was at least one bit set to one.
+static bool mi_bitmap_is_claimedx_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* pany_ones) {
+  size_t idx = mi_bitmap_index_field(bitmap_idx);
+  size_t pre_mask;
+  size_t mid_mask;
+  size_t post_mask;
+  size_t mid_count = mi_bitmap_mask_across(bitmap_idx, bitmap_fields, count, &pre_mask, &mid_mask, &post_mask);
+  bool all_ones = true;
+  bool any_ones = false;
+  mi_bitmap_field_t* field = &bitmap[idx];
+  size_t prev = mi_atomic_load_relaxed(field++);
+  if ((prev & pre_mask) != pre_mask) all_ones = false;
+  if ((prev & pre_mask) != 0) any_ones = true;
+  while (mid_count-- > 0) {
+    prev = mi_atomic_load_relaxed(field++);
+    if ((prev & mid_mask) != mid_mask) all_ones = false;
+    if ((prev & mid_mask) != 0) any_ones = true;
+  }
+  if (post_mask!=0) {
+    prev = mi_atomic_load_relaxed(field);
+    if ((prev & post_mask) != post_mask) all_ones = false;
+    if ((prev & post_mask) != 0) any_ones = true;
+  }
+  if (pany_ones != NULL) { *pany_ones = any_ones; }
+  return all_ones;
+}
+
+bool _mi_bitmap_is_claimed_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
+  return mi_bitmap_is_claimedx_across(bitmap, bitmap_fields, count, bitmap_idx, NULL);
+}
+
+bool _mi_bitmap_is_any_claimed_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
+  bool any_ones;
+  mi_bitmap_is_claimedx_across(bitmap, bitmap_fields, count, bitmap_idx, &any_ones);
+  return any_ones;
+}
diff --git a/compat/mimalloc/bitmap.h b/compat/mimalloc/bitmap.h
new file mode 100644
index 00000000000000..9ba15d5d6f09ea
--- /dev/null
+++ b/compat/mimalloc/bitmap.h
@@ -0,0 +1,115 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2019-2023 Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+
+/* ----------------------------------------------------------------------------
+Concurrent bitmap that can set/reset sequences of bits atomically,
+represeted as an array of fields where each field is a machine word (`size_t`)
+
+There are two api's; the standard one cannot have sequences that cross
+between the bitmap fields (and a sequence must be <= MI_BITMAP_FIELD_BITS).
+(this is used in region allocation)
+
+The `_across` postfixed functions do allow sequences that can cross over
+between the fields. (This is used in arena allocation)
+---------------------------------------------------------------------------- */
+#pragma once
+#ifndef MI_BITMAP_H
+#define MI_BITMAP_H
+
+/* -----------------------------------------------------------
+  Bitmap definition
+----------------------------------------------------------- */
+
+#define MI_BITMAP_FIELD_BITS   (8*MI_SIZE_SIZE)
+#define MI_BITMAP_FIELD_FULL   (~((size_t)0))   // all bits set
+
+// An atomic bitmap of `size_t` fields
+typedef _Atomic(size_t)  mi_bitmap_field_t;
+typedef mi_bitmap_field_t*  mi_bitmap_t;
+
+// A bitmap index is the index of the bit in a bitmap.
+typedef size_t mi_bitmap_index_t;
+
+// Create a bit index.
+static inline mi_bitmap_index_t mi_bitmap_index_create(size_t idx, size_t bitidx) {
+  mi_assert_internal(bitidx < MI_BITMAP_FIELD_BITS);
+  return (idx*MI_BITMAP_FIELD_BITS) + bitidx;
+}
+
+// Create a bit index.
+static inline mi_bitmap_index_t mi_bitmap_index_create_from_bit(size_t full_bitidx) {
+  return mi_bitmap_index_create(full_bitidx / MI_BITMAP_FIELD_BITS, full_bitidx % MI_BITMAP_FIELD_BITS);
+}
+
+// Get the field index from a bit index.
+static inline size_t mi_bitmap_index_field(mi_bitmap_index_t bitmap_idx) {
+  return (bitmap_idx / MI_BITMAP_FIELD_BITS);
+}
+
+// Get the bit index in a bitmap field
+static inline size_t mi_bitmap_index_bit_in_field(mi_bitmap_index_t bitmap_idx) {
+  return (bitmap_idx % MI_BITMAP_FIELD_BITS);
+}
+
+// Get the full bit index
+static inline size_t mi_bitmap_index_bit(mi_bitmap_index_t bitmap_idx) {
+  return bitmap_idx;
+}
+
+/* -----------------------------------------------------------
+  Claim a bit sequence atomically
+----------------------------------------------------------- */
+
+// Try to atomically claim a sequence of `count` bits in a single
+// field at `idx` in `bitmap`. Returns `true` on success.
+bool _mi_bitmap_try_find_claim_field(mi_bitmap_t bitmap, size_t idx, const size_t count, mi_bitmap_index_t* bitmap_idx);
+
+// Starts at idx, and wraps around to search in all `bitmap_fields` fields.
+// For now, `count` can be at most MI_BITMAP_FIELD_BITS and will never cross fields.
+bool _mi_bitmap_try_find_from_claim(mi_bitmap_t bitmap, const size_t bitmap_fields, const size_t start_field_idx, const size_t count, mi_bitmap_index_t* bitmap_idx);
+
+// Like _mi_bitmap_try_find_from_claim but with an extra predicate that must be fullfilled
+typedef bool (mi_cdecl *mi_bitmap_pred_fun_t)(mi_bitmap_index_t bitmap_idx, void* pred_arg);
+bool _mi_bitmap_try_find_from_claim_pred(mi_bitmap_t bitmap, const size_t bitmap_fields, const size_t start_field_idx, const size_t count, mi_bitmap_pred_fun_t pred_fun, void* pred_arg, mi_bitmap_index_t* bitmap_idx);
+
+// Set `count` bits at `bitmap_idx` to 0 atomically
+// Returns `true` if all `count` bits were 1 previously.
+bool _mi_bitmap_unclaim(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx);
+
+// Try to set `count` bits at `bitmap_idx` from 0 to 1 atomically.
+// Returns `true` if successful when all previous `count` bits were 0.
+bool _mi_bitmap_try_claim(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx);
+
+// Set `count` bits at `bitmap_idx` to 1 atomically
+// Returns `true` if all `count` bits were 0 previously. `any_zero` is `true` if there was at least one zero bit.
+bool _mi_bitmap_claim(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* any_zero);
+
+bool _mi_bitmap_is_claimed(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx);
+bool _mi_bitmap_is_any_claimed(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx);
+
+
+//--------------------------------------------------------------------------
+// the `_across` functions work on bitmaps where sequences can cross over
+// between the fields. This is used in arena allocation
+//--------------------------------------------------------------------------
+
+// Find `count` bits of zeros and set them to 1 atomically; returns `true` on success.
+// Starts at idx, and wraps around to search in all `bitmap_fields` fields.
+bool _mi_bitmap_try_find_from_claim_across(mi_bitmap_t bitmap, const size_t bitmap_fields, const size_t start_field_idx, const size_t count, mi_bitmap_index_t* bitmap_idx);
+
+// Set `count` bits at `bitmap_idx` to 0 atomically
+// Returns `true` if all `count` bits were 1 previously.
+bool _mi_bitmap_unclaim_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx);
+
+// Set `count` bits at `bitmap_idx` to 1 atomically
+// Returns `true` if all `count` bits were 0 previously. `any_zero` is `true` if there was at least one zero bit.
+bool _mi_bitmap_claim_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* pany_zero);
+
+bool _mi_bitmap_is_claimed_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx);
+bool _mi_bitmap_is_any_claimed_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx);
+
+#endif
diff --git a/compat/mimalloc/heap.c b/compat/mimalloc/heap.c
new file mode 100644
index 00000000000000..dab8c4bf8ae388
--- /dev/null
+++ b/compat/mimalloc/heap.c
@@ -0,0 +1,626 @@
+/*----------------------------------------------------------------------------
+Copyright (c) 2018-2021, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "mimalloc/atomic.h"
+#include "mimalloc/prim.h"  // mi_prim_get_default_heap
+
+#include <string.h>  // memset, memcpy
+
+#if defined(_MSC_VER) && (_MSC_VER < 1920)
+#pragma warning(disable:4204)  // non-constant aggregate initializer
+#endif
+
+/* -----------------------------------------------------------
+  Helpers
+----------------------------------------------------------- */
+
+// return `true` if ok, `false` to break
+typedef bool (heap_page_visitor_fun)(mi_heap_t* heap, mi_page_queue_t* pq, mi_page_t* page, void* arg1, void* arg2);
+
+// Visit all pages in a heap; returns `false` if break was called.
+static bool mi_heap_visit_pages(mi_heap_t* heap, heap_page_visitor_fun* fn, void* arg1, void* arg2)
+{
+  if (heap==NULL || heap->page_count==0) return 0;
+
+  // visit all pages
+  #if MI_DEBUG>1
+  size_t total = heap->page_count;
+  size_t count = 0;
+  #endif
+
+  for (size_t i = 0; i <= MI_BIN_FULL; i++) {
+    mi_page_queue_t* pq = &heap->pages[i];
+    mi_page_t* page = pq->first;
+    while(page != NULL) {
+      mi_page_t* next = page->next; // save next in case the page gets removed from the queue
+      mi_assert_internal(mi_page_heap(page) == heap);
+      #if MI_DEBUG>1
+      count++;
+      #endif
+      if (!fn(heap, pq, page, arg1, arg2)) return false;
+      page = next; // and continue
+    }
+  }
+  mi_assert_internal(count == total);
+  return true;
+}
+
+
+#if MI_DEBUG>=2
+static bool mi_heap_page_is_valid(mi_heap_t* heap, mi_page_queue_t* pq, mi_page_t* page, void* arg1, void* arg2) {
+  MI_UNUSED(arg1);
+  MI_UNUSED(arg2);
+  MI_UNUSED(pq);
+  mi_assert_internal(mi_page_heap(page) == heap);
+  mi_segment_t* segment = _mi_page_segment(page);
+  mi_assert_internal(segment->thread_id == heap->thread_id);
+  mi_assert_expensive(_mi_page_is_valid(page));
+  return true;
+}
+#endif
+#if MI_DEBUG>=3
+static bool mi_heap_is_valid(mi_heap_t* heap) {
+  mi_assert_internal(heap!=NULL);
+  mi_heap_visit_pages(heap, &mi_heap_page_is_valid, NULL, NULL);
+  return true;
+}
+#endif
+
+
+
+
+/* -----------------------------------------------------------
+  "Collect" pages by migrating `local_free` and `thread_free`
+  lists and freeing empty pages. This is done when a thread
+  stops (and in that case abandons pages if there are still
+  blocks alive)
+----------------------------------------------------------- */
+
+typedef enum mi_collect_e {
+  MI_NORMAL,
+  MI_FORCE,
+  MI_ABANDON
+} mi_collect_t;
+
+
+static bool mi_heap_page_collect(mi_heap_t* heap, mi_page_queue_t* pq, mi_page_t* page, void* arg_collect, void* arg2 ) {
+  MI_UNUSED(arg2);
+  MI_UNUSED(heap);
+  mi_assert_internal(mi_heap_page_is_valid(heap, pq, page, NULL, NULL));
+  mi_collect_t collect = *((mi_collect_t*)arg_collect);
+  _mi_page_free_collect(page, collect >= MI_FORCE);
+  if (mi_page_all_free(page)) {
+    // no more used blocks, free the page.
+    // note: this will free retired pages as well.
+    _mi_page_free(page, pq, collect >= MI_FORCE);
+  }
+  else if (collect == MI_ABANDON) {
+    // still used blocks but the thread is done; abandon the page
+    _mi_page_abandon(page, pq);
+  }
+  return true; // don't break
+}
+
+static bool mi_heap_page_never_delayed_free(mi_heap_t* heap, mi_page_queue_t* pq, mi_page_t* page, void* arg1, void* arg2) {
+  MI_UNUSED(arg1);
+  MI_UNUSED(arg2);
+  MI_UNUSED(heap);
+  MI_UNUSED(pq);
+  _mi_page_use_delayed_free(page, MI_NEVER_DELAYED_FREE, false);
+  return true; // don't break
+}
+
+static void mi_heap_collect_ex(mi_heap_t* heap, mi_collect_t collect)
+{
+  if (heap==NULL || !mi_heap_is_initialized(heap)) return;
+
+  const bool force = collect >= MI_FORCE;
+  _mi_deferred_free(heap, force);
+
+  // note: never reclaim on collect but leave it to threads that need storage to reclaim
+  const bool force_main =
+    #ifdef NDEBUG
+      collect == MI_FORCE
+    #else
+      collect >= MI_FORCE
+    #endif
+      && _mi_is_main_thread() && mi_heap_is_backing(heap) && !heap->no_reclaim;
+
+  if (force_main) {
+    // the main thread is abandoned (end-of-program), try to reclaim all abandoned segments.
+    // if all memory is freed by now, all segments should be freed.
+    _mi_abandoned_reclaim_all(heap, &heap->tld->segments);
+  }
+
+  // if abandoning, mark all pages to no longer add to delayed_free
+  if (collect == MI_ABANDON) {
+    mi_heap_visit_pages(heap, &mi_heap_page_never_delayed_free, NULL, NULL);
+  }
+
+  // free all current thread delayed blocks.
+  // (if abandoning, after this there are no more thread-delayed references into the pages.)
+  _mi_heap_delayed_free_all(heap);
+
+  // collect retired pages
+  _mi_heap_collect_retired(heap, force);
+
+  // collect all pages owned by this thread
+  mi_heap_visit_pages(heap, &mi_heap_page_collect, &collect, NULL);
+  mi_assert_internal( collect != MI_ABANDON || mi_atomic_load_ptr_acquire(mi_block_t,&heap->thread_delayed_free) == NULL );
+
+  // collect abandoned segments (in particular, purge expired parts of segments in the abandoned segment list)
+  // note: forced purge can be quite expensive if many threads are created/destroyed so we do not force on abandonment
+  _mi_abandoned_collect(heap, collect == MI_FORCE /* force? */, &heap->tld->segments);
+
+  // collect segment local caches
+  if (force) {
+    _mi_segment_thread_collect(&heap->tld->segments);
+  }
+
+  // collect regions on program-exit (or shared library unload)
+  if (force && _mi_is_main_thread() && mi_heap_is_backing(heap)) {
+    _mi_thread_data_collect();  // collect thread data cache
+    _mi_arena_collect(true /* force purge */, &heap->tld->stats);
+  }
+}
+
+void _mi_heap_collect_abandon(mi_heap_t* heap) {
+  mi_heap_collect_ex(heap, MI_ABANDON);
+}
+
+void mi_heap_collect(mi_heap_t* heap, bool force) mi_attr_noexcept {
+  mi_heap_collect_ex(heap, (force ? MI_FORCE : MI_NORMAL));
+}
+
+void mi_collect(bool force) mi_attr_noexcept {
+  mi_heap_collect(mi_prim_get_default_heap(), force);
+}
+
+
+/* -----------------------------------------------------------
+  Heap new
+----------------------------------------------------------- */
+
+mi_heap_t* mi_heap_get_default(void) {
+  mi_thread_init();
+  return mi_prim_get_default_heap();
+}
+
+static bool mi_heap_is_default(const mi_heap_t* heap) {
+  return (heap == mi_prim_get_default_heap());
+}
+
+
+mi_heap_t* mi_heap_get_backing(void) {
+  mi_heap_t* heap = mi_heap_get_default();
+  mi_assert_internal(heap!=NULL);
+  mi_heap_t* bheap = heap->tld->heap_backing;
+  mi_assert_internal(bheap!=NULL);
+  mi_assert_internal(bheap->thread_id == _mi_thread_id());
+  return bheap;
+}
+
+mi_decl_nodiscard mi_heap_t* mi_heap_new_in_arena(mi_arena_id_t arena_id) {
+  mi_heap_t* bheap = mi_heap_get_backing();
+  mi_heap_t* heap = mi_heap_malloc_tp(bheap, mi_heap_t);  // todo: OS allocate in secure mode?
+  if (heap == NULL) return NULL;
+  _mi_memcpy_aligned(heap, &_mi_heap_empty, sizeof(mi_heap_t));
+  heap->tld = bheap->tld;
+  heap->thread_id = _mi_thread_id();
+  heap->arena_id = arena_id;
+  _mi_random_split(&bheap->random, &heap->random);
+  heap->cookie = _mi_heap_random_next(heap) | 1;
+  heap->keys[0] = _mi_heap_random_next(heap);
+  heap->keys[1] = _mi_heap_random_next(heap);
+  heap->no_reclaim = true;  // don't reclaim abandoned pages or otherwise destroy is unsafe
+  // push on the thread local heaps list
+  heap->next = heap->tld->heaps;
+  heap->tld->heaps = heap;
+  return heap;
+}
+
+mi_decl_nodiscard mi_heap_t* mi_heap_new(void) {
+  return mi_heap_new_in_arena(_mi_arena_id_none());
+}
+
+bool _mi_heap_memid_is_suitable(mi_heap_t* heap, mi_memid_t memid) {
+  return _mi_arena_memid_is_suitable(memid, heap->arena_id);
+}
+
+uintptr_t _mi_heap_random_next(mi_heap_t* heap) {
+  return _mi_random_next(&heap->random);
+}
+
+// zero out the page queues
+static void mi_heap_reset_pages(mi_heap_t* heap) {
+  mi_assert_internal(heap != NULL);
+  mi_assert_internal(mi_heap_is_initialized(heap));
+  // TODO: copy full empty heap instead?
+  memset(&heap->pages_free_direct, 0, sizeof(heap->pages_free_direct));
+  _mi_memcpy_aligned(&heap->pages, &_mi_heap_empty.pages, sizeof(heap->pages));
+  heap->thread_delayed_free = NULL;
+  heap->page_count = 0;
+}
+
+// called from `mi_heap_destroy` and `mi_heap_delete` to free the internal heap resources.
+static void mi_heap_free(mi_heap_t* heap) {
+  mi_assert(heap != NULL);
+  mi_assert_internal(mi_heap_is_initialized(heap));
+  if (heap==NULL || !mi_heap_is_initialized(heap)) return;
+  if (mi_heap_is_backing(heap)) return; // dont free the backing heap
+
+  // reset default
+  if (mi_heap_is_default(heap)) {
+    _mi_heap_set_default_direct(heap->tld->heap_backing);
+  }
+
+  // remove ourselves from the thread local heaps list
+  // linear search but we expect the number of heaps to be relatively small
+  mi_heap_t* prev = NULL;
+  mi_heap_t* curr = heap->tld->heaps;
+  while (curr != heap && curr != NULL) {
+    prev = curr;
+    curr = curr->next;
+  }
+  mi_assert_internal(curr == heap);
+  if (curr == heap) {
+    if (prev != NULL) { prev->next = heap->next; }
+		 else { heap->tld->heaps = heap->next; }
+  }
+  mi_assert_internal(heap->tld->heaps != NULL);
+
+  // and free the used memory
+  mi_free(heap);
+}
+
+
+/* -----------------------------------------------------------
+  Heap destroy
+----------------------------------------------------------- */
+
+static bool _mi_heap_page_destroy(mi_heap_t* heap, mi_page_queue_t* pq, mi_page_t* page, void* arg1, void* arg2) {
+  MI_UNUSED(arg1);
+  MI_UNUSED(arg2);
+  MI_UNUSED(heap);
+  MI_UNUSED(pq);
+
+  // ensure no more thread_delayed_free will be added
+  _mi_page_use_delayed_free(page, MI_NEVER_DELAYED_FREE, false);
+
+  // stats
+  const size_t bsize = mi_page_block_size(page);
+  if (bsize > MI_MEDIUM_OBJ_SIZE_MAX) {
+    if (bsize <= MI_LARGE_OBJ_SIZE_MAX) {
+      mi_heap_stat_decrease(heap, large, bsize);
+    }
+    else {
+      mi_heap_stat_decrease(heap, huge, bsize);
+    }
+  }
+#if (MI_STAT)
+  _mi_page_free_collect(page, false);  // update used count
+  const size_t inuse = page->used;
+  if (bsize <= MI_LARGE_OBJ_SIZE_MAX) {
+    mi_heap_stat_decrease(heap, normal, bsize * inuse);
+#if (MI_STAT>1)
+    mi_heap_stat_decrease(heap, normal_bins[_mi_bin(bsize)], inuse);
+#endif
+  }
+  mi_heap_stat_decrease(heap, malloc, bsize * inuse);  // todo: off for aligned blocks...
+#endif
+
+  /// pretend it is all free now
+  mi_assert_internal(mi_page_thread_free(page) == NULL);
+  page->used = 0;
+
+  // and free the page
+  // mi_page_free(page,false);
+  page->next = NULL;
+  page->prev = NULL;
+  _mi_segment_page_free(page,false /* no force? */, &heap->tld->segments);
+
+  return true; // keep going
+}
+
+void _mi_heap_destroy_pages(mi_heap_t* heap) {
+  mi_heap_visit_pages(heap, &_mi_heap_page_destroy, NULL, NULL);
+  mi_heap_reset_pages(heap);
+}
+
+#if MI_TRACK_HEAP_DESTROY
+static bool mi_cdecl mi_heap_track_block_free(const mi_heap_t* heap, const mi_heap_area_t* area, void* block, size_t block_size, void* arg) {
+  MI_UNUSED(heap); MI_UNUSED(area);  MI_UNUSED(arg); MI_UNUSED(block_size);
+  mi_track_free_size(block,mi_usable_size(block));
+  return true;
+}
+#endif
+
+void mi_heap_destroy(mi_heap_t* heap) {
+  mi_assert(heap != NULL);
+  mi_assert(mi_heap_is_initialized(heap));
+  mi_assert(heap->no_reclaim);
+  mi_assert_expensive(mi_heap_is_valid(heap));
+  if (heap==NULL || !mi_heap_is_initialized(heap)) return;
+  if (!heap->no_reclaim) {
+    // don't free in case it may contain reclaimed pages
+    mi_heap_delete(heap);
+  }
+  else {
+    // track all blocks as freed
+    #if MI_TRACK_HEAP_DESTROY
+    mi_heap_visit_blocks(heap, true, mi_heap_track_block_free, NULL);
+    #endif
+    // free all pages
+    _mi_heap_destroy_pages(heap);
+    mi_heap_free(heap);
+  }
+}
+
+// forcefully destroy all heaps in the current thread
+void _mi_heap_unsafe_destroy_all(void) {
+  mi_heap_t* bheap = mi_heap_get_backing();
+  mi_heap_t* curr = bheap->tld->heaps;
+  while (curr != NULL) {
+    mi_heap_t* next = curr->next;
+    if (curr->no_reclaim) {
+      mi_heap_destroy(curr);
+    }
+    else {
+      _mi_heap_destroy_pages(curr);
+    }
+    curr = next;
+  }
+}
+
+/* -----------------------------------------------------------
+  Safe Heap delete
+----------------------------------------------------------- */
+
+// Transfer the pages from one heap to the other
+static void mi_heap_absorb(mi_heap_t* heap, mi_heap_t* from) {
+  mi_assert_internal(heap!=NULL);
+  if (from==NULL || from->page_count == 0) return;
+
+  // reduce the size of the delayed frees
+  _mi_heap_delayed_free_partial(from);
+
+  // transfer all pages by appending the queues; this will set a new heap field
+  // so threads may do delayed frees in either heap for a while.
+  // note: appending waits for each page to not be in the `MI_DELAYED_FREEING` state
+  // so after this only the new heap will get delayed frees
+  for (size_t i = 0; i <= MI_BIN_FULL; i++) {
+    mi_page_queue_t* pq = &heap->pages[i];
+    mi_page_queue_t* append = &from->pages[i];
+    size_t pcount = _mi_page_queue_append(heap, pq, append);
+    heap->page_count += pcount;
+    from->page_count -= pcount;
+  }
+  mi_assert_internal(from->page_count == 0);
+
+  // and do outstanding delayed frees in the `from` heap
+  // note: be careful here as the `heap` field in all those pages no longer point to `from`,
+  // turns out to be ok as `_mi_heap_delayed_free` only visits the list and calls a
+  // the regular `_mi_free_delayed_block` which is safe.
+  _mi_heap_delayed_free_all(from);
+  #if !defined(_MSC_VER) || (_MSC_VER > 1900) // somehow the following line gives an error in VS2015, issue #353
+  mi_assert_internal(mi_atomic_load_ptr_relaxed(mi_block_t,&from->thread_delayed_free) == NULL);
+  #endif
+
+  // and reset the `from` heap
+  mi_heap_reset_pages(from);
+}
+
+// Safe delete a heap without freeing any still allocated blocks in that heap.
+void mi_heap_delete(mi_heap_t* heap)
+{
+  mi_assert(heap != NULL);
+  mi_assert(mi_heap_is_initialized(heap));
+  mi_assert_expensive(mi_heap_is_valid(heap));
+  if (heap==NULL || !mi_heap_is_initialized(heap)) return;
+
+  if (!mi_heap_is_backing(heap)) {
+    // tranfer still used pages to the backing heap
+    mi_heap_absorb(heap->tld->heap_backing, heap);
+  }
+  else {
+    // the backing heap abandons its pages
+    _mi_heap_collect_abandon(heap);
+  }
+  mi_assert_internal(heap->page_count==0);
+  mi_heap_free(heap);
+}
+
+mi_heap_t* mi_heap_set_default(mi_heap_t* heap) {
+  mi_assert(heap != NULL);
+  mi_assert(mi_heap_is_initialized(heap));
+  if (heap==NULL || !mi_heap_is_initialized(heap)) return NULL;
+  mi_assert_expensive(mi_heap_is_valid(heap));
+  mi_heap_t* old = mi_prim_get_default_heap();
+  _mi_heap_set_default_direct(heap);
+  return old;
+}
+
+
+
+
+/* -----------------------------------------------------------
+  Analysis
+----------------------------------------------------------- */
+
+// static since it is not thread safe to access heaps from other threads.
+static mi_heap_t* mi_heap_of_block(const void* p) {
+  if (p == NULL) return NULL;
+  mi_segment_t* segment = _mi_ptr_segment(p);
+  bool valid = (_mi_ptr_cookie(segment) == segment->cookie);
+  mi_assert_internal(valid);
+  if mi_unlikely(!valid) return NULL;
+  return mi_page_heap(_mi_segment_page_of(segment,p));
+}
+
+bool mi_heap_contains_block(mi_heap_t* heap, const void* p) {
+  mi_assert(heap != NULL);
+  if (heap==NULL || !mi_heap_is_initialized(heap)) return false;
+  return (heap == mi_heap_of_block(p));
+}
+
+
+static bool mi_heap_page_check_owned(mi_heap_t* heap, mi_page_queue_t* pq, mi_page_t* page, void* p, void* vfound) {
+  MI_UNUSED(heap);
+  MI_UNUSED(pq);
+  bool* found = (bool*)vfound;
+  mi_segment_t* segment = _mi_page_segment(page);
+  void* start = _mi_page_start(segment, page, NULL);
+  void* end   = (uint8_t*)start + (page->capacity * mi_page_block_size(page));
+  *found = (p >= start && p < end);
+  return (!*found); // continue if not found
+}
+
+bool mi_heap_check_owned(mi_heap_t* heap, const void* p) {
+  mi_assert(heap != NULL);
+  if (heap==NULL || !mi_heap_is_initialized(heap)) return false;
+  if (((uintptr_t)p & (MI_INTPTR_SIZE - 1)) != 0) return false;  // only aligned pointers
+  bool found = false;
+  mi_heap_visit_pages(heap, &mi_heap_page_check_owned, (void*)p, &found);
+  return found;
+}
+
+bool mi_check_owned(const void* p) {
+  return mi_heap_check_owned(mi_prim_get_default_heap(), p);
+}
+
+/* -----------------------------------------------------------
+  Visit all heap blocks and areas
+  Todo: enable visiting abandoned pages, and
+	enable visiting all blocks of all heaps across threads
+----------------------------------------------------------- */
+
+// Separate struct to keep `mi_page_t` out of the public interface
+typedef struct mi_heap_area_ex_s {
+  mi_heap_area_t area;
+  mi_page_t*     page;
+} mi_heap_area_ex_t;
+
+static bool mi_heap_area_visit_blocks(const mi_heap_area_ex_t* xarea, mi_block_visit_fun* visitor, void* arg) {
+  mi_assert(xarea != NULL);
+  if (xarea==NULL) return true;
+  const mi_heap_area_t* area = &xarea->area;
+  mi_page_t* page = xarea->page;
+  mi_assert(page != NULL);
+  if (page == NULL) return true;
+
+  _mi_page_free_collect(page,true);
+  mi_assert_internal(page->local_free == NULL);
+  if (page->used == 0) return true;
+
+  const size_t bsize = mi_page_block_size(page);
+  const size_t ubsize = mi_page_usable_block_size(page); // without padding
+  size_t   psize;
+  uint8_t* pstart = _mi_page_start(_mi_page_segment(page), page, &psize);
+
+  if (page->capacity == 1) {
+    // optimize page with one block
+    mi_assert_internal(page->used == 1 && page->free == NULL);
+    return visitor(mi_page_heap(page), area, pstart, ubsize, arg);
+  }
+
+  // create a bitmap of free blocks.
+  #define MI_MAX_BLOCKS   (MI_SMALL_PAGE_SIZE / sizeof(void*))
+  uintptr_t free_map[MI_MAX_BLOCKS / sizeof(uintptr_t)];
+  memset(free_map, 0, sizeof(free_map));
+
+  #if MI_DEBUG>1
+  size_t free_count = 0;
+  #endif
+  for (mi_block_t* block = page->free; block != NULL; block = mi_block_next(page,block)) {
+    #if MI_DEBUG>1
+    free_count++;
+    #endif
+    mi_assert_internal((uint8_t*)block >= pstart && (uint8_t*)block < (pstart + psize));
+    size_t offset = (uint8_t*)block - pstart;
+    mi_assert_internal(offset % bsize == 0);
+    size_t blockidx = offset / bsize;  // Todo: avoid division?
+    mi_assert_internal( blockidx < MI_MAX_BLOCKS);
+    size_t bitidx = (blockidx / sizeof(uintptr_t));
+    size_t bit = blockidx - (bitidx * sizeof(uintptr_t));
+    free_map[bitidx] |= ((uintptr_t)1 << bit);
+  }
+  mi_assert_internal(page->capacity == (free_count + page->used));
+
+  // walk through all blocks skipping the free ones
+  #if MI_DEBUG>1
+  size_t used_count = 0;
+  #endif
+  for (size_t i = 0; i < page->capacity; i++) {
+    size_t bitidx = (i / sizeof(uintptr_t));
+    size_t bit = i - (bitidx * sizeof(uintptr_t));
+    uintptr_t m = free_map[bitidx];
+    if (bit == 0 && m == UINTPTR_MAX) {
+      i += (sizeof(uintptr_t) - 1); // skip a run of free blocks
+    }
+    else if ((m & ((uintptr_t)1 << bit)) == 0) {
+      #if MI_DEBUG>1
+      used_count++;
+      #endif
+      uint8_t* block = pstart + (i * bsize);
+      if (!visitor(mi_page_heap(page), area, block, ubsize, arg)) return false;
+    }
+  }
+  mi_assert_internal(page->used == used_count);
+  return true;
+}
+
+typedef bool (mi_heap_area_visit_fun)(const mi_heap_t* heap, const mi_heap_area_ex_t* area, void* arg);
+
+
+static bool mi_heap_visit_areas_page(mi_heap_t* heap, mi_page_queue_t* pq, mi_page_t* page, void* vfun, void* arg) {
+  MI_UNUSED(heap);
+  MI_UNUSED(pq);
+  mi_heap_area_visit_fun* fun = (mi_heap_area_visit_fun*)vfun;
+  mi_heap_area_ex_t xarea;
+  const size_t bsize = mi_page_block_size(page);
+  const size_t ubsize = mi_page_usable_block_size(page);
+  xarea.page = page;
+  xarea.area.reserved = page->reserved * bsize;
+  xarea.area.committed = page->capacity * bsize;
+  xarea.area.blocks = _mi_page_start(_mi_page_segment(page), page, NULL);
+  xarea.area.used = page->used;   // number of blocks in use (#553)
+  xarea.area.block_size = ubsize;
+  xarea.area.full_block_size = bsize;
+  return fun(heap, &xarea, arg);
+}
+
+// Visit all heap pages as areas
+static bool mi_heap_visit_areas(const mi_heap_t* heap, mi_heap_area_visit_fun* visitor, void* arg) {
+  if (visitor == NULL) return false;
+  return mi_heap_visit_pages((mi_heap_t*)heap, &mi_heap_visit_areas_page, (void*)(visitor), arg); // note: function pointer to void* :-{
+}
+
+// Just to pass arguments
+typedef struct mi_visit_blocks_args_s {
+  bool  visit_blocks;
+  mi_block_visit_fun* visitor;
+  void* arg;
+} mi_visit_blocks_args_t;
+
+static bool mi_heap_area_visitor(const mi_heap_t* heap, const mi_heap_area_ex_t* xarea, void* arg) {
+  mi_visit_blocks_args_t* args = (mi_visit_blocks_args_t*)arg;
+  if (!args->visitor(heap, &xarea->area, NULL, xarea->area.block_size, args->arg)) return false;
+  if (args->visit_blocks) {
+    return mi_heap_area_visit_blocks(xarea, args->visitor, args->arg);
+  }
+  else {
+    return true;
+  }
+}
+
+// Visit all blocks in a heap
+bool mi_heap_visit_blocks(const mi_heap_t* heap, bool visit_blocks, mi_block_visit_fun* visitor, void* arg) {
+  mi_visit_blocks_args_t args = { visit_blocks, visitor, arg };
+  return mi_heap_visit_areas(heap, &mi_heap_area_visitor, &args);
+}
diff --git a/compat/mimalloc/init.c b/compat/mimalloc/init.c
new file mode 100644
index 00000000000000..4670d5510db187
--- /dev/null
+++ b/compat/mimalloc/init.c
@@ -0,0 +1,709 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2022, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "mimalloc/prim.h"
+
+#include <string.h>  // memcpy, memset
+#include <stdlib.h>  // atexit
+
+
+// Empty page used to initialize the small free pages array
+const mi_page_t _mi_page_empty = {
+  0, false, false, false,
+  0,       // capacity
+  0,       // reserved capacity
+  { 0 },   // flags
+  false,   // is_zero
+  0,       // retire_expire
+  NULL,    // free
+  0,       // used
+  0,       // xblock_size
+  NULL,    // local_free
+  #if (MI_PADDING || MI_ENCODE_FREELIST)
+  { 0, 0 },
+  #endif
+  MI_ATOMIC_VAR_INIT(0), // xthread_free
+  MI_ATOMIC_VAR_INIT(0), // xheap
+  NULL, NULL
+  #if MI_INTPTR_SIZE==8
+  , { 0 }  // padding
+  #endif
+};
+
+#define MI_PAGE_EMPTY() ((mi_page_t*)&_mi_page_empty)
+
+#if (MI_SMALL_WSIZE_MAX==128)
+#if (MI_PADDING>0) && (MI_INTPTR_SIZE >= 8)
+#define MI_SMALL_PAGES_EMPTY  { MI_INIT128(MI_PAGE_EMPTY), MI_PAGE_EMPTY(), MI_PAGE_EMPTY() }
+#elif (MI_PADDING>0)
+#define MI_SMALL_PAGES_EMPTY  { MI_INIT128(MI_PAGE_EMPTY), MI_PAGE_EMPTY(), MI_PAGE_EMPTY(), MI_PAGE_EMPTY() }
+#else
+#define MI_SMALL_PAGES_EMPTY  { MI_INIT128(MI_PAGE_EMPTY), MI_PAGE_EMPTY() }
+#endif
+#else
+#error "define right initialization sizes corresponding to MI_SMALL_WSIZE_MAX"
+#endif
+
+// Empty page queues for every bin
+#define QNULL(sz)  { NULL, NULL, (sz)*sizeof(uintptr_t) }
+#define MI_PAGE_QUEUES_EMPTY \
+  { QNULL(1), \
+    QNULL(     1), QNULL(     2), QNULL(     3), QNULL(     4), QNULL(     5), QNULL(     6), QNULL(     7), QNULL(     8), /* 8 */ \
+    QNULL(    10), QNULL(    12), QNULL(    14), QNULL(    16), QNULL(    20), QNULL(    24), QNULL(    28), QNULL(    32), /* 16 */ \
+    QNULL(    40), QNULL(    48), QNULL(    56), QNULL(    64), QNULL(    80), QNULL(    96), QNULL(   112), QNULL(   128), /* 24 */ \
+    QNULL(   160), QNULL(   192), QNULL(   224), QNULL(   256), QNULL(   320), QNULL(   384), QNULL(   448), QNULL(   512), /* 32 */ \
+    QNULL(   640), QNULL(   768), QNULL(   896), QNULL(  1024), QNULL(  1280), QNULL(  1536), QNULL(  1792), QNULL(  2048), /* 40 */ \
+    QNULL(  2560), QNULL(  3072), QNULL(  3584), QNULL(  4096), QNULL(  5120), QNULL(  6144), QNULL(  7168), QNULL(  8192), /* 48 */ \
+    QNULL( 10240), QNULL( 12288), QNULL( 14336), QNULL( 16384), QNULL( 20480), QNULL( 24576), QNULL( 28672), QNULL( 32768), /* 56 */ \
+    QNULL( 40960), QNULL( 49152), QNULL( 57344), QNULL( 65536), QNULL( 81920), QNULL( 98304), QNULL(114688), QNULL(131072), /* 64 */ \
+    QNULL(163840), QNULL(196608), QNULL(229376), QNULL(262144), QNULL(327680), QNULL(393216), QNULL(458752), QNULL(524288), /* 72 */ \
+    QNULL(MI_MEDIUM_OBJ_WSIZE_MAX + 1  /* 655360, Huge queue */), \
+    QNULL(MI_MEDIUM_OBJ_WSIZE_MAX + 2) /* Full queue */ }
+
+#define MI_STAT_COUNT_NULL()  {0,0,0,0}
+
+// Empty statistics
+#if MI_STAT>1
+#define MI_STAT_COUNT_END_NULL()  , { MI_STAT_COUNT_NULL(), MI_INIT32(MI_STAT_COUNT_NULL) }
+#else
+#define MI_STAT_COUNT_END_NULL()
+#endif
+
+#define MI_STATS_NULL  \
+  MI_STAT_COUNT_NULL(), MI_STAT_COUNT_NULL(), \
+  MI_STAT_COUNT_NULL(), MI_STAT_COUNT_NULL(), \
+  MI_STAT_COUNT_NULL(), MI_STAT_COUNT_NULL(), \
+  MI_STAT_COUNT_NULL(), MI_STAT_COUNT_NULL(), \
+  MI_STAT_COUNT_NULL(), MI_STAT_COUNT_NULL(), \
+  MI_STAT_COUNT_NULL(), MI_STAT_COUNT_NULL(), \
+  MI_STAT_COUNT_NULL(), MI_STAT_COUNT_NULL(), \
+  MI_STAT_COUNT_NULL(), \
+  { 0, 0 }, { 0, 0 }, { 0, 0 }, { 0, 0 }, \
+  { 0, 0 }, { 0, 0 }, { 0, 0 }, { 0, 0 }, { 0, 0 }, { 0, 0 } \
+  MI_STAT_COUNT_END_NULL()
+
+
+// Empty slice span queues for every bin
+#define SQNULL(sz)  { NULL, NULL, sz }
+#define MI_SEGMENT_SPAN_QUEUES_EMPTY \
+  { SQNULL(1), \
+    SQNULL(     1), SQNULL(     2), SQNULL(     3), SQNULL(     4), SQNULL(     5), SQNULL(     6), SQNULL(     7), SQNULL(    10), /*  8 */ \
+    SQNULL(    12), SQNULL(    14), SQNULL(    16), SQNULL(    20), SQNULL(    24), SQNULL(    28), SQNULL(    32), SQNULL(    40), /* 16 */ \
+    SQNULL(    48), SQNULL(    56), SQNULL(    64), SQNULL(    80), SQNULL(    96), SQNULL(   112), SQNULL(   128), SQNULL(   160), /* 24 */ \
+    SQNULL(   192), SQNULL(   224), SQNULL(   256), SQNULL(   320), SQNULL(   384), SQNULL(   448), SQNULL(   512), SQNULL(   640), /* 32 */ \
+    SQNULL(   768), SQNULL(   896), SQNULL(  1024) /* 35 */ }
+
+
+// --------------------------------------------------------
+// Statically allocate an empty heap as the initial
+// thread local value for the default heap,
+// and statically allocate the backing heap for the main
+// thread so it can function without doing any allocation
+// itself (as accessing a thread local for the first time
+// may lead to allocation itself on some platforms)
+// --------------------------------------------------------
+
+mi_decl_cache_align const mi_heap_t _mi_heap_empty = {
+  NULL,
+  MI_SMALL_PAGES_EMPTY,
+  MI_PAGE_QUEUES_EMPTY,
+  MI_ATOMIC_VAR_INIT(NULL),
+  0,                // tid
+  0,                // cookie
+  0,                // arena id
+  { 0, 0 },         // keys
+  { {0}, {0}, 0, true }, // random
+  0,                // page count
+  MI_BIN_FULL, 0,   // page retired min/max
+  NULL,             // next
+  false
+};
+
+#define tld_empty_stats  ((mi_stats_t*)((uint8_t*)&tld_empty + offsetof(mi_tld_t,stats)))
+#define tld_empty_os     ((mi_os_tld_t*)((uint8_t*)&tld_empty + offsetof(mi_tld_t,os)))
+
+mi_decl_cache_align static const mi_tld_t tld_empty = {
+  0,
+  false,
+  NULL, NULL,
+  { MI_SEGMENT_SPAN_QUEUES_EMPTY, 0, 0, 0, 0, tld_empty_stats, tld_empty_os }, // segments
+  { 0, tld_empty_stats }, // os
+  { MI_STATS_NULL }       // stats
+};
+
+mi_threadid_t _mi_thread_id(void) mi_attr_noexcept {
+  return _mi_prim_thread_id();
+}
+
+// the thread-local default heap for allocation
+mi_decl_thread mi_heap_t* _mi_heap_default = (mi_heap_t*)&_mi_heap_empty;
+
+extern mi_heap_t _mi_heap_main;
+
+static mi_tld_t tld_main = {
+  0, false,
+  &_mi_heap_main, & _mi_heap_main,
+  { MI_SEGMENT_SPAN_QUEUES_EMPTY, 0, 0, 0, 0, &tld_main.stats, &tld_main.os }, // segments
+  { 0, &tld_main.stats },  // os
+  { MI_STATS_NULL }       // stats
+};
+
+mi_heap_t _mi_heap_main = {
+  &tld_main,
+  MI_SMALL_PAGES_EMPTY,
+  MI_PAGE_QUEUES_EMPTY,
+  MI_ATOMIC_VAR_INIT(NULL),
+  0,                // thread id
+  0,                // initial cookie
+  0,                // arena id
+  { 0, 0 },         // the key of the main heap can be fixed (unlike page keys that need to be secure!)
+  { {0x846ca68b}, {0}, 0, true },  // random
+  0,                // page count
+  MI_BIN_FULL, 0,   // page retired min/max
+  NULL,             // next heap
+  false             // can reclaim
+};
+
+bool _mi_process_is_initialized = false;  // set to `true` in `mi_process_init`.
+
+mi_stats_t _mi_stats_main = { MI_STATS_NULL };
+
+
+static void mi_heap_main_init(void) {
+  if (_mi_heap_main.cookie == 0) {
+    _mi_heap_main.thread_id = _mi_thread_id();
+    _mi_heap_main.cookie = 1;
+    #if defined(_WIN32) && !defined(MI_SHARED_LIB)
+      _mi_random_init_weak(&_mi_heap_main.random);    // prevent allocation failure during bcrypt dll initialization with static linking
+    #else
+      _mi_random_init(&_mi_heap_main.random);
+    #endif
+    _mi_heap_main.cookie  = _mi_heap_random_next(&_mi_heap_main);
+    _mi_heap_main.keys[0] = _mi_heap_random_next(&_mi_heap_main);
+    _mi_heap_main.keys[1] = _mi_heap_random_next(&_mi_heap_main);
+  }
+}
+
+mi_heap_t* _mi_heap_main_get(void) {
+  mi_heap_main_init();
+  return &_mi_heap_main;
+}
+
+
+/* -----------------------------------------------------------
+  Initialization and freeing of the thread local heaps
+----------------------------------------------------------- */
+
+// note: in x64 in release build `sizeof(mi_thread_data_t)` is under 4KiB (= OS page size).
+typedef struct mi_thread_data_s {
+  mi_heap_t  heap;  // must come first due to cast in `_mi_heap_done`
+  mi_tld_t   tld;
+  mi_memid_t memid;
+} mi_thread_data_t;
+
+
+// Thread meta-data is allocated directly from the OS. For
+// some programs that do not use thread pools and allocate and
+// destroy many OS threads, this may causes too much overhead
+// per thread so we maintain a small cache of recently freed metadata.
+
+#define TD_CACHE_SIZE (16)
+static _Atomic(mi_thread_data_t*) td_cache[TD_CACHE_SIZE];
+
+static mi_thread_data_t* mi_thread_data_zalloc(void) {
+  // try to find thread metadata in the cache
+  bool is_zero = false;
+  mi_thread_data_t* td = NULL;
+  for (int i = 0; i < TD_CACHE_SIZE; i++) {
+    td = mi_atomic_load_ptr_relaxed(mi_thread_data_t, &td_cache[i]);
+    if (td != NULL) {
+      // found cached allocation, try use it
+      td = mi_atomic_exchange_ptr_acq_rel(mi_thread_data_t, &td_cache[i], NULL);
+      if (td != NULL) {
+	break;
+      }
+    }
+  }
+
+  // if that fails, allocate as meta data
+  if (td == NULL) {
+    mi_memid_t memid;
+    td = (mi_thread_data_t*)_mi_os_alloc(sizeof(mi_thread_data_t), &memid, &_mi_stats_main);
+    if (td == NULL) {
+      // if this fails, try once more. (issue #257)
+      td = (mi_thread_data_t*)_mi_os_alloc(sizeof(mi_thread_data_t), &memid, &_mi_stats_main);
+      if (td == NULL) {
+	// really out of memory
+	_mi_error_message(ENOMEM, "unable to allocate thread local heap metadata (%zu bytes)\n", sizeof(mi_thread_data_t));
+      }
+    }
+    if (td != NULL) {
+      td->memid = memid;
+      is_zero = memid.initially_zero;
+    }
+  }
+
+  if (td != NULL && !is_zero) {
+    _mi_memzero_aligned(td, sizeof(*td));
+  }
+  return td;
+}
+
+static void mi_thread_data_free( mi_thread_data_t* tdfree ) {
+  // try to add the thread metadata to the cache
+  for (int i = 0; i < TD_CACHE_SIZE; i++) {
+    mi_thread_data_t* td = mi_atomic_load_ptr_relaxed(mi_thread_data_t, &td_cache[i]);
+    if (td == NULL) {
+      mi_thread_data_t* expected = NULL;
+      if (mi_atomic_cas_ptr_weak_acq_rel(mi_thread_data_t, &td_cache[i], &expected, tdfree)) {
+	return;
+      }
+    }
+  }
+  // if that fails, just free it directly
+  _mi_os_free(tdfree, sizeof(mi_thread_data_t), tdfree->memid, &_mi_stats_main);
+}
+
+void _mi_thread_data_collect(void) {
+  // free all thread metadata from the cache
+  for (int i = 0; i < TD_CACHE_SIZE; i++) {
+    mi_thread_data_t* td = mi_atomic_load_ptr_relaxed(mi_thread_data_t, &td_cache[i]);
+    if (td != NULL) {
+      td = mi_atomic_exchange_ptr_acq_rel(mi_thread_data_t, &td_cache[i], NULL);
+      if (td != NULL) {
+	_mi_os_free(td, sizeof(mi_thread_data_t), td->memid, &_mi_stats_main);
+      }
+    }
+  }
+}
+
+// Initialize the thread local default heap, called from `mi_thread_init`
+static bool _mi_heap_init(void) {
+  if (mi_heap_is_initialized(mi_prim_get_default_heap())) return true;
+  if (_mi_is_main_thread()) {
+    // mi_assert_internal(_mi_heap_main.thread_id != 0);  // can happen on freeBSD where alloc is called before any initialization
+    // the main heap is statically allocated
+    mi_heap_main_init();
+    _mi_heap_set_default_direct(&_mi_heap_main);
+    //mi_assert_internal(_mi_heap_default->tld->heap_backing == mi_prim_get_default_heap());
+  }
+  else {
+    // use `_mi_os_alloc` to allocate directly from the OS
+    mi_thread_data_t* td = mi_thread_data_zalloc();
+    if (td == NULL) return false;
+
+    mi_tld_t*  tld = &td->tld;
+    mi_heap_t* heap = &td->heap;
+    _mi_memcpy_aligned(tld, &tld_empty, sizeof(*tld));
+    _mi_memcpy_aligned(heap, &_mi_heap_empty, sizeof(*heap));
+    heap->thread_id = _mi_thread_id();
+    _mi_random_init(&heap->random);
+    heap->cookie  = _mi_heap_random_next(heap) | 1;
+    heap->keys[0] = _mi_heap_random_next(heap);
+    heap->keys[1] = _mi_heap_random_next(heap);
+    heap->tld = tld;
+    tld->heap_backing = heap;
+    tld->heaps = heap;
+    tld->segments.stats = &tld->stats;
+    tld->segments.os = &tld->os;
+    tld->os.stats = &tld->stats;
+    _mi_heap_set_default_direct(heap);
+  }
+  return false;
+}
+
+// Free the thread local default heap (called from `mi_thread_done`)
+static bool _mi_heap_done(mi_heap_t* heap) {
+  if (!mi_heap_is_initialized(heap)) return true;
+
+  // reset default heap
+  _mi_heap_set_default_direct(_mi_is_main_thread() ? &_mi_heap_main : (mi_heap_t*)&_mi_heap_empty);
+
+  // switch to backing heap
+  heap = heap->tld->heap_backing;
+  if (!mi_heap_is_initialized(heap)) return false;
+
+  // delete all non-backing heaps in this thread
+  mi_heap_t* curr = heap->tld->heaps;
+  while (curr != NULL) {
+    mi_heap_t* next = curr->next; // save `next` as `curr` will be freed
+    if (curr != heap) {
+      mi_assert_internal(!mi_heap_is_backing(curr));
+      mi_heap_delete(curr);
+    }
+    curr = next;
+  }
+  mi_assert_internal(heap->tld->heaps == heap && heap->next == NULL);
+  mi_assert_internal(mi_heap_is_backing(heap));
+
+  // collect if not the main thread
+  if (heap != &_mi_heap_main) {
+    _mi_heap_collect_abandon(heap);
+  }
+
+  // merge stats
+  _mi_stats_done(&heap->tld->stats);
+
+  // free if not the main thread
+  if (heap != &_mi_heap_main) {
+    // the following assertion does not always hold for huge segments as those are always treated
+    // as abondened: one may allocate it in one thread, but deallocate in another in which case
+    // the count can be too large or negative. todo: perhaps not count huge segments? see issue #363
+    // mi_assert_internal(heap->tld->segments.count == 0 || heap->thread_id != _mi_thread_id());
+    mi_thread_data_free((mi_thread_data_t*)heap);
+  }
+  else {
+    #if 0
+    // never free the main thread even in debug mode; if a dll is linked statically with mimalloc,
+    // there may still be delete/free calls after the mi_fls_done is called. Issue #207
+    _mi_heap_destroy_pages(heap);
+    mi_assert_internal(heap->tld->heap_backing == &_mi_heap_main);
+    #endif
+  }
+  return false;
+}
+
+
+
+// --------------------------------------------------------
+// Try to run `mi_thread_done()` automatically so any memory
+// owned by the thread but not yet released can be abandoned
+// and re-owned by another thread.
+//
+// 1. windows dynamic library:
+//     call from DllMain on DLL_THREAD_DETACH
+// 2. windows static library:
+//     use `FlsAlloc` to call a destructor when the thread is done
+// 3. unix, pthreads:
+//     use a pthread key to call a destructor when a pthread is done
+//
+// In the last two cases we also need to call `mi_process_init`
+// to set up the thread local keys.
+// --------------------------------------------------------
+
+// Set up handlers so `mi_thread_done` is called automatically
+static void mi_process_setup_auto_thread_done(void) {
+  static bool tls_initialized = false; // fine if it races
+  if (tls_initialized) return;
+  tls_initialized = true;
+  _mi_prim_thread_init_auto_done();
+  _mi_heap_set_default_direct(&_mi_heap_main);
+}
+
+
+bool _mi_is_main_thread(void) {
+  return (_mi_heap_main.thread_id==0 || _mi_heap_main.thread_id == _mi_thread_id());
+}
+
+static _Atomic(size_t) thread_count = MI_ATOMIC_VAR_INIT(1);
+
+size_t  _mi_current_thread_count(void) {
+  return mi_atomic_load_relaxed(&thread_count);
+}
+
+// This is called from the `mi_malloc_generic`
+void mi_thread_init(void) mi_attr_noexcept
+{
+  // ensure our process has started already
+  mi_process_init();
+
+  // initialize the thread local default heap
+  // (this will call `_mi_heap_set_default_direct` and thus set the
+  //  fiber/pthread key to a non-zero value, ensuring `_mi_thread_done` is called)
+  if (_mi_heap_init()) return;  // returns true if already initialized
+
+  _mi_stat_increase(&_mi_stats_main.threads, 1);
+  mi_atomic_increment_relaxed(&thread_count);
+  //_mi_verbose_message("thread init: 0x%zx\n", _mi_thread_id());
+}
+
+void mi_thread_done(void) mi_attr_noexcept {
+  _mi_thread_done(NULL);
+}
+
+void _mi_thread_done(mi_heap_t* heap)
+{
+  // calling with NULL implies using the default heap
+  if (heap == NULL) {
+    heap = mi_prim_get_default_heap();
+    if (heap == NULL) return;
+  }
+
+  // prevent re-entrancy through heap_done/heap_set_default_direct (issue #699)
+  if (!mi_heap_is_initialized(heap)) {
+    return;
+  }
+
+  // adjust stats
+  mi_atomic_decrement_relaxed(&thread_count);
+  _mi_stat_decrease(&_mi_stats_main.threads, 1);
+
+  // check thread-id as on Windows shutdown with FLS the main (exit) thread may call this on thread-local heaps...
+  if (heap->thread_id != _mi_thread_id()) return;
+
+  // abandon the thread local heap
+  if (_mi_heap_done(heap)) return;  // returns true if already ran
+}
+
+void _mi_heap_set_default_direct(mi_heap_t* heap)  {
+  mi_assert_internal(heap != NULL);
+  #if defined(MI_TLS_SLOT)
+  mi_prim_tls_slot_set(MI_TLS_SLOT,heap);
+  #elif defined(MI_TLS_PTHREAD_SLOT_OFS)
+  *mi_tls_pthread_heap_slot() = heap;
+  #elif defined(MI_TLS_PTHREAD)
+  // we use _mi_heap_default_key
+  #else
+  _mi_heap_default = heap;
+  #endif
+
+  // ensure the default heap is passed to `_mi_thread_done`
+  // setting to a non-NULL value also ensures `mi_thread_done` is called.
+  _mi_prim_thread_associate_default_heap(heap);
+}
+
+
+// --------------------------------------------------------
+// Run functions on process init/done, and thread init/done
+// --------------------------------------------------------
+static void mi_cdecl mi_process_done(void);
+
+static bool os_preloading = true;    // true until this module is initialized
+static bool mi_redirected = false;   // true if malloc redirects to mi_malloc
+
+// Returns true if this module has not been initialized; Don't use C runtime routines until it returns false.
+bool mi_decl_noinline _mi_preloading(void) {
+  return os_preloading;
+}
+
+mi_decl_nodiscard bool mi_is_redirected(void) mi_attr_noexcept {
+  return mi_redirected;
+}
+
+// Communicate with the redirection module on Windows
+#if defined(_WIN32) && defined(MI_SHARED_LIB) && !defined(MI_WIN_NOREDIRECT)
+#ifdef __cplusplus
+extern "C" {
+#endif
+mi_decl_export void _mi_redirect_entry(DWORD reason) {
+  // called on redirection; careful as this may be called before DllMain
+  if (reason == DLL_PROCESS_ATTACH) {
+    mi_redirected = true;
+  }
+  else if (reason == DLL_PROCESS_DETACH) {
+    mi_redirected = false;
+  }
+  else if (reason == DLL_THREAD_DETACH) {
+    mi_thread_done();
+  }
+}
+__declspec(dllimport) bool mi_cdecl mi_allocator_init(const char** message);
+__declspec(dllimport) void mi_cdecl mi_allocator_done(void);
+#ifdef __cplusplus
+}
+#endif
+#else
+static bool mi_allocator_init(const char** message) {
+  if (message != NULL) *message = NULL;
+  return true;
+}
+static void mi_allocator_done(void) {
+  // nothing to do
+}
+#endif
+
+// Called once by the process loader
+static void mi_process_load(void) {
+  mi_heap_main_init();
+  #if defined(__APPLE__) || defined(MI_TLS_RECURSE_GUARD)
+  volatile mi_heap_t* dummy = _mi_heap_default; // access TLS to allocate it before setting tls_initialized to true;
+  if (dummy == NULL) return;                    // use dummy or otherwise the access may get optimized away (issue #697)
+  #endif
+  os_preloading = false;
+  mi_assert_internal(_mi_is_main_thread());
+  #if !(defined(_WIN32) && defined(MI_SHARED_LIB))  // use Dll process detach (see below) instead of atexit (issue #521)
+  atexit(&mi_process_done);
+  #endif
+  _mi_options_init();
+  mi_process_setup_auto_thread_done();
+  mi_process_init();
+  if (mi_redirected) _mi_verbose_message("malloc is redirected.\n");
+
+  // show message from the redirector (if present)
+  const char* msg = NULL;
+  mi_allocator_init(&msg);
+  if (msg != NULL && (mi_option_is_enabled(mi_option_verbose) || mi_option_is_enabled(mi_option_show_errors))) {
+    _mi_fputs(NULL,NULL,NULL,msg);
+  }
+
+  // reseed random
+  _mi_random_reinit_if_weak(&_mi_heap_main.random);
+}
+
+#if defined(_WIN32) && (defined(_M_IX86) || defined(_M_X64))
+#include <intrin.h>
+mi_decl_cache_align bool _mi_cpu_has_fsrm = false;
+
+static void mi_detect_cpu_features(void) {
+  // FSRM for fast rep movsb support (AMD Zen3+ (~2020) or Intel Ice Lake+ (~2017))
+  int32_t cpu_info[4];
+  __cpuid(cpu_info, 7);
+  _mi_cpu_has_fsrm = ((cpu_info[3] & (1 << 4)) != 0); // bit 4 of EDX : see <https://en.wikipedia.org/wiki/CPUID#EAX=7,_ECX=0:_Extended_Features>
+}
+#else
+static void mi_detect_cpu_features(void) {
+  // nothing
+}
+#endif
+
+// Initialize the process; called by thread_init or the process loader
+void mi_process_init(void) mi_attr_noexcept {
+  // ensure we are called once
+  static mi_atomic_once_t process_init;
+	#if _MSC_VER < 1920
+	mi_heap_main_init(); // vs2017 can dynamically re-initialize _mi_heap_main
+	#endif
+  if (!mi_atomic_once(&process_init)) return;
+  _mi_process_is_initialized = true;
+  _mi_verbose_message("process init: 0x%zx\n", _mi_thread_id());
+  mi_process_setup_auto_thread_done();
+
+  mi_detect_cpu_features();
+  _mi_os_init();
+  mi_heap_main_init();
+  #if MI_DEBUG
+  _mi_verbose_message("debug level : %d\n", MI_DEBUG);
+  #endif
+  _mi_verbose_message("secure level: %d\n", MI_SECURE);
+  _mi_verbose_message("mem tracking: %s\n", MI_TRACK_TOOL);
+  #if MI_TSAN
+  _mi_verbose_message("thread santizer enabled\n");
+  #endif
+  mi_thread_init();
+
+  #if defined(_WIN32)
+  // On windows, when building as a static lib the FLS cleanup happens to early for the main thread.
+  // To avoid this, set the FLS value for the main thread to NULL so the fls cleanup
+  // will not call _mi_thread_done on the (still executing) main thread. See issue #508.
+  _mi_prim_thread_associate_default_heap(NULL);
+  #endif
+
+  mi_stats_reset();  // only call stat reset *after* thread init (or the heap tld == NULL)
+  mi_track_init();
+
+  if (mi_option_is_enabled(mi_option_reserve_huge_os_pages)) {
+    size_t pages = mi_option_get_clamp(mi_option_reserve_huge_os_pages, 0, 128*1024);
+    long reserve_at = mi_option_get(mi_option_reserve_huge_os_pages_at);
+    if (reserve_at != -1) {
+      mi_reserve_huge_os_pages_at(pages, reserve_at, pages*500);
+    } else {
+      mi_reserve_huge_os_pages_interleave(pages, 0, pages*500);
+    }
+  }
+  if (mi_option_is_enabled(mi_option_reserve_os_memory)) {
+    long ksize = mi_option_get(mi_option_reserve_os_memory);
+    if (ksize > 0) {
+      mi_reserve_os_memory((size_t)ksize*MI_KiB, true /* commit? */, true /* allow large pages? */);
+    }
+  }
+}
+
+// Called when the process is done (through `at_exit`)
+static void mi_cdecl mi_process_done(void) {
+  // only shutdown if we were initialized
+  if (!_mi_process_is_initialized) return;
+  // ensure we are called once
+  static bool process_done = false;
+  if (process_done) return;
+  process_done = true;
+
+  // release any thread specific resources and ensure _mi_thread_done is called on all but the main thread
+  _mi_prim_thread_done_auto_done();
+
+  #ifndef MI_SKIP_COLLECT_ON_EXIT
+    #if (MI_DEBUG || !defined(MI_SHARED_LIB))
+    // free all memory if possible on process exit. This is not needed for a stand-alone process
+    // but should be done if mimalloc is statically linked into another shared library which
+    // is repeatedly loaded/unloaded, see issue #281.
+    mi_collect(true /* force */ );
+    #endif
+  #endif
+
+  // Forcefully release all retained memory; this can be dangerous in general if overriding regular malloc/free
+  // since after process_done there might still be other code running that calls `free` (like at_exit routines,
+  // or C-runtime termination code.
+  if (mi_option_is_enabled(mi_option_destroy_on_exit)) {
+    mi_collect(true /* force */);
+    _mi_heap_unsafe_destroy_all();     // forcefully release all memory held by all heaps (of this thread only!)
+    _mi_arena_unsafe_destroy_all(& _mi_heap_main_get()->tld->stats);
+  }
+
+  if (mi_option_is_enabled(mi_option_show_stats) || mi_option_is_enabled(mi_option_verbose)) {
+    mi_stats_print(NULL);
+  }
+  mi_allocator_done();
+  _mi_verbose_message("process done: 0x%zx\n", _mi_heap_main.thread_id);
+  os_preloading = true; // don't call the C runtime anymore
+}
+
+
+
+#if defined(_WIN32) && defined(MI_SHARED_LIB)
+  // Windows DLL: easy to hook into process_init and thread_done
+  __declspec(dllexport) BOOL WINAPI DllMain(HINSTANCE inst, DWORD reason, LPVOID reserved) {
+    MI_UNUSED(reserved);
+    MI_UNUSED(inst);
+    if (reason==DLL_PROCESS_ATTACH) {
+      mi_process_load();
+    }
+    else if (reason==DLL_PROCESS_DETACH) {
+      mi_process_done();
+    }
+    else if (reason==DLL_THREAD_DETACH) {
+      if (!mi_is_redirected()) {
+	mi_thread_done();
+      }
+    }
+    return TRUE;
+  }
+
+#elif defined(_MSC_VER)
+  // MSVC: use data section magic for static libraries
+  // See <https://www.codeguru.com/cpp/misc/misc/applicationcontrol/article.php/c6945/Running-Code-Before-and-After-Main.htm>
+  static int _mi_process_init(void) {
+    mi_process_load();
+    return 0;
+  }
+  typedef int(*_mi_crt_callback_t)(void);
+  #if defined(_M_X64) || defined(_M_ARM64)
+    __pragma(comment(linker, "/include:" "_mi_msvc_initu"))
+    #pragma section(".CRT$XIU", long, read)
+  #else
+    __pragma(comment(linker, "/include:" "__mi_msvc_initu"))
+  #endif
+  #pragma data_seg(".CRT$XIU")
+  mi_decl_externc _mi_crt_callback_t _mi_msvc_initu[] = { &_mi_process_init };
+  #pragma data_seg()
+
+#elif defined(__cplusplus)
+  // C++: use static initialization to detect process start
+  static bool _mi_process_init(void) {
+    mi_process_load();
+    return (_mi_heap_main.thread_id != 0);
+  }
+  static bool mi_initialized = _mi_process_init();
+
+#elif defined(__GNUC__) || defined(__clang__)
+  // GCC,Clang: use the constructor attribute
+  static void __attribute__((constructor)) _mi_process_init(void) {
+    mi_process_load();
+  }
+
+#else
+#pragma message("define a way to call mi_process_load on your platform")
+#endif
diff --git a/compat/mimalloc/mimalloc.h b/compat/mimalloc/mimalloc.h
new file mode 100644
index 00000000000000..c0f5e96e51e975
--- /dev/null
+++ b/compat/mimalloc/mimalloc.h
@@ -0,0 +1,565 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2023, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+#pragma once
+#ifndef MIMALLOC_H
+#define MIMALLOC_H
+
+#define MI_MALLOC_VERSION 212   // major + 2 digits minor
+
+// ------------------------------------------------------
+// Compiler specific attributes
+// ------------------------------------------------------
+
+#ifdef __cplusplus
+  #if (__cplusplus >= 201103L) || (_MSC_VER > 1900)  // C++11
+    #define mi_attr_noexcept   noexcept
+  #else
+    #define mi_attr_noexcept   throw()
+  #endif
+#else
+  #define mi_attr_noexcept
+#endif
+
+#if defined(__cplusplus) && (__cplusplus >= 201703)
+  #define mi_decl_nodiscard    [[nodiscard]]
+#elif (defined(__GNUC__) && (__GNUC__ >= 4)) || defined(__clang__)  // includes clang, icc, and clang-cl
+  #define mi_decl_nodiscard    __attribute__((warn_unused_result))
+#elif defined(_HAS_NODISCARD)
+  #define mi_decl_nodiscard    _NODISCARD
+#elif (_MSC_VER >= 1700)
+  #define mi_decl_nodiscard    _Check_return_
+#else
+  #define mi_decl_nodiscard
+#endif
+
+#if defined(_MSC_VER) || defined(__MINGW32__)
+  #if !defined(MI_SHARED_LIB)
+    #define mi_decl_export
+  #elif defined(MI_SHARED_LIB_EXPORT)
+    #define mi_decl_export              __declspec(dllexport)
+  #else
+    #define mi_decl_export              __declspec(dllimport)
+  #endif
+  #if defined(__MINGW32__)
+    #define mi_decl_restrict
+    #define mi_attr_malloc              __attribute__((malloc))
+  #else
+    #if (_MSC_VER >= 1900) && !defined(__EDG__)
+      #define mi_decl_restrict          __declspec(allocator) __declspec(restrict)
+    #else
+      #define mi_decl_restrict          __declspec(restrict)
+    #endif
+    #define mi_attr_malloc
+  #endif
+  #define mi_cdecl                      __cdecl
+  #define mi_attr_alloc_size(s)
+  #define mi_attr_alloc_size2(s1,s2)
+  #define mi_attr_alloc_align(p)
+#elif defined(__GNUC__)                 // includes clang and icc
+  #if defined(MI_SHARED_LIB) && defined(MI_SHARED_LIB_EXPORT)
+    #define mi_decl_export              __attribute__((visibility("default")))
+  #else
+    #define mi_decl_export
+  #endif
+  #define mi_cdecl                      // leads to warnings... __attribute__((cdecl))
+  #define mi_decl_restrict
+  #define mi_attr_malloc                __attribute__((malloc))
+  #if (defined(__clang_major__) && (__clang_major__ < 4)) || (__GNUC__ < 5)
+    #define mi_attr_alloc_size(s)
+    #define mi_attr_alloc_size2(s1,s2)
+    #define mi_attr_alloc_align(p)
+  #elif defined(__INTEL_COMPILER)
+    #define mi_attr_alloc_size(s)       __attribute__((alloc_size(s)))
+    #define mi_attr_alloc_size2(s1,s2)  __attribute__((alloc_size(s1,s2)))
+    #define mi_attr_alloc_align(p)
+  #else
+    #define mi_attr_alloc_size(s)       __attribute__((alloc_size(s)))
+    #define mi_attr_alloc_size2(s1,s2)  __attribute__((alloc_size(s1,s2)))
+    #define mi_attr_alloc_align(p)      __attribute__((alloc_align(p)))
+  #endif
+#else
+  #define mi_cdecl
+  #define mi_decl_export
+  #define mi_decl_restrict
+  #define mi_attr_malloc
+  #define mi_attr_alloc_size(s)
+  #define mi_attr_alloc_size2(s1,s2)
+  #define mi_attr_alloc_align(p)
+#endif
+
+// ------------------------------------------------------
+// Includes
+// ------------------------------------------------------
+
+#include <stddef.h>     // size_t
+#include <stdbool.h>    // bool
+#include <stdint.h>     // INTPTR_MAX
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// ------------------------------------------------------
+// Standard malloc interface
+// ------------------------------------------------------
+
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_malloc(size_t size)  mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(1);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_calloc(size_t count, size_t size)  mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size2(1,2);
+mi_decl_nodiscard mi_decl_export void* mi_realloc(void* p, size_t newsize)      mi_attr_noexcept mi_attr_alloc_size(2);
+mi_decl_export void* mi_expand(void* p, size_t newsize)                         mi_attr_noexcept mi_attr_alloc_size(2);
+
+mi_decl_export void mi_free(void* p) mi_attr_noexcept;
+mi_decl_nodiscard mi_decl_export mi_decl_restrict char* mi_strdup(const char* s) mi_attr_noexcept mi_attr_malloc;
+mi_decl_nodiscard mi_decl_export mi_decl_restrict char* mi_strndup(const char* s, size_t n) mi_attr_noexcept mi_attr_malloc;
+mi_decl_nodiscard mi_decl_export mi_decl_restrict char* mi_realpath(const char* fname, char* resolved_name) mi_attr_noexcept mi_attr_malloc;
+
+// ------------------------------------------------------
+// Extended functionality
+// ------------------------------------------------------
+#define MI_SMALL_WSIZE_MAX  (128)
+#define MI_SMALL_SIZE_MAX   (MI_SMALL_WSIZE_MAX*sizeof(void*))
+
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_malloc_small(size_t size) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(1);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_zalloc_small(size_t size) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(1);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_zalloc(size_t size)       mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(1);
+
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_mallocn(size_t count, size_t size) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size2(1,2);
+mi_decl_nodiscard mi_decl_export void* mi_reallocn(void* p, size_t count, size_t size)        mi_attr_noexcept mi_attr_alloc_size2(2,3);
+mi_decl_nodiscard mi_decl_export void* mi_reallocf(void* p, size_t newsize)                   mi_attr_noexcept mi_attr_alloc_size(2);
+
+mi_decl_nodiscard mi_decl_export size_t mi_usable_size(const void* p) mi_attr_noexcept;
+mi_decl_nodiscard mi_decl_export size_t mi_good_size(size_t size)     mi_attr_noexcept;
+
+
+// ------------------------------------------------------
+// Internals
+// ------------------------------------------------------
+
+typedef void (mi_cdecl mi_deferred_free_fun)(bool force, unsigned long long heartbeat, void* arg);
+mi_decl_export void mi_register_deferred_free(mi_deferred_free_fun* deferred_free, void* arg) mi_attr_noexcept;
+
+typedef void (mi_cdecl mi_output_fun)(const char* msg, void* arg);
+mi_decl_export void mi_register_output(mi_output_fun* out, void* arg) mi_attr_noexcept;
+
+typedef void (mi_cdecl mi_error_fun)(int err, void* arg);
+mi_decl_export void mi_register_error(mi_error_fun* fun, void* arg);
+
+mi_decl_export void mi_collect(bool force)    mi_attr_noexcept;
+mi_decl_export int  mi_version(void)          mi_attr_noexcept;
+mi_decl_export void mi_stats_reset(void)      mi_attr_noexcept;
+mi_decl_export void mi_stats_merge(void)      mi_attr_noexcept;
+mi_decl_export void mi_stats_print(void* out) mi_attr_noexcept;  // backward compatibility: `out` is ignored and should be NULL
+mi_decl_export void mi_stats_print_out(mi_output_fun* out, void* arg) mi_attr_noexcept;
+
+mi_decl_export void mi_process_init(void)     mi_attr_noexcept;
+mi_decl_export void mi_thread_init(void)      mi_attr_noexcept;
+mi_decl_export void mi_thread_done(void)      mi_attr_noexcept;
+mi_decl_export void mi_thread_stats_print_out(mi_output_fun* out, void* arg) mi_attr_noexcept;
+
+mi_decl_export void mi_process_info(size_t* elapsed_msecs, size_t* user_msecs, size_t* system_msecs,
+				    size_t* current_rss, size_t* peak_rss,
+				    size_t* current_commit, size_t* peak_commit, size_t* page_faults) mi_attr_noexcept;
+
+// -------------------------------------------------------------------------------------
+// Aligned allocation
+// Note that `alignment` always follows `size` for consistency with unaligned
+// allocation, but unfortunately this differs from `posix_memalign` and `aligned_alloc`.
+// -------------------------------------------------------------------------------------
+
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_malloc_aligned(size_t size, size_t alignment) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(1) mi_attr_alloc_align(2);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_malloc_aligned_at(size_t size, size_t alignment, size_t offset) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(1);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_zalloc_aligned(size_t size, size_t alignment) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(1) mi_attr_alloc_align(2);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_zalloc_aligned_at(size_t size, size_t alignment, size_t offset) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(1);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_calloc_aligned(size_t count, size_t size, size_t alignment) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size2(1,2) mi_attr_alloc_align(3);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_calloc_aligned_at(size_t count, size_t size, size_t alignment, size_t offset) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size2(1,2);
+mi_decl_nodiscard mi_decl_export void* mi_realloc_aligned(void* p, size_t newsize, size_t alignment) mi_attr_noexcept mi_attr_alloc_size(2) mi_attr_alloc_align(3);
+mi_decl_nodiscard mi_decl_export void* mi_realloc_aligned_at(void* p, size_t newsize, size_t alignment, size_t offset) mi_attr_noexcept mi_attr_alloc_size(2);
+
+
+// -------------------------------------------------------------------------------------
+// Heaps: first-class, but can only allocate from the same thread that created it.
+// -------------------------------------------------------------------------------------
+
+struct mi_heap_s;
+typedef struct mi_heap_s mi_heap_t;
+
+mi_decl_nodiscard mi_decl_export mi_heap_t* mi_heap_new(void);
+mi_decl_export void       mi_heap_delete(mi_heap_t* heap);
+mi_decl_export void       mi_heap_destroy(mi_heap_t* heap);
+mi_decl_export mi_heap_t* mi_heap_set_default(mi_heap_t* heap);
+mi_decl_export mi_heap_t* mi_heap_get_default(void);
+mi_decl_export mi_heap_t* mi_heap_get_backing(void);
+mi_decl_export void       mi_heap_collect(mi_heap_t* heap, bool force) mi_attr_noexcept;
+
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_heap_malloc(mi_heap_t* heap, size_t size) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(2);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_heap_zalloc(mi_heap_t* heap, size_t size) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(2);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_heap_calloc(mi_heap_t* heap, size_t count, size_t size) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size2(2, 3);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_heap_mallocn(mi_heap_t* heap, size_t count, size_t size) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size2(2, 3);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_heap_malloc_small(mi_heap_t* heap, size_t size) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(2);
+
+mi_decl_nodiscard mi_decl_export void* mi_heap_realloc(mi_heap_t* heap, void* p, size_t newsize)              mi_attr_noexcept mi_attr_alloc_size(3);
+mi_decl_nodiscard mi_decl_export void* mi_heap_reallocn(mi_heap_t* heap, void* p, size_t count, size_t size)  mi_attr_noexcept mi_attr_alloc_size2(3,4);
+mi_decl_nodiscard mi_decl_export void* mi_heap_reallocf(mi_heap_t* heap, void* p, size_t newsize)             mi_attr_noexcept mi_attr_alloc_size(3);
+
+mi_decl_nodiscard mi_decl_export mi_decl_restrict char* mi_heap_strdup(mi_heap_t* heap, const char* s)            mi_attr_noexcept mi_attr_malloc;
+mi_decl_nodiscard mi_decl_export mi_decl_restrict char* mi_heap_strndup(mi_heap_t* heap, const char* s, size_t n) mi_attr_noexcept mi_attr_malloc;
+mi_decl_nodiscard mi_decl_export mi_decl_restrict char* mi_heap_realpath(mi_heap_t* heap, const char* fname, char* resolved_name) mi_attr_noexcept mi_attr_malloc;
+
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_heap_malloc_aligned(mi_heap_t* heap, size_t size, size_t alignment) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(2) mi_attr_alloc_align(3);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_heap_malloc_aligned_at(mi_heap_t* heap, size_t size, size_t alignment, size_t offset) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(2);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_heap_zalloc_aligned(mi_heap_t* heap, size_t size, size_t alignment) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(2) mi_attr_alloc_align(3);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_heap_zalloc_aligned_at(mi_heap_t* heap, size_t size, size_t alignment, size_t offset) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(2);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_heap_calloc_aligned(mi_heap_t* heap, size_t count, size_t size, size_t alignment) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size2(2, 3) mi_attr_alloc_align(4);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_heap_calloc_aligned_at(mi_heap_t* heap, size_t count, size_t size, size_t alignment, size_t offset) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size2(2, 3);
+mi_decl_nodiscard mi_decl_export void* mi_heap_realloc_aligned(mi_heap_t* heap, void* p, size_t newsize, size_t alignment) mi_attr_noexcept mi_attr_alloc_size(3) mi_attr_alloc_align(4);
+mi_decl_nodiscard mi_decl_export void* mi_heap_realloc_aligned_at(mi_heap_t* heap, void* p, size_t newsize, size_t alignment, size_t offset) mi_attr_noexcept mi_attr_alloc_size(3);
+
+
+// --------------------------------------------------------------------------------
+// Zero initialized re-allocation.
+// Only valid on memory that was originally allocated with zero initialization too.
+// e.g. `mi_calloc`, `mi_zalloc`, `mi_zalloc_aligned` etc.
+// see <https://github.com/microsoft/mimalloc/issues/63#issuecomment-508272992>
+// --------------------------------------------------------------------------------
+
+mi_decl_nodiscard mi_decl_export void* mi_rezalloc(void* p, size_t newsize)                mi_attr_noexcept mi_attr_alloc_size(2);
+mi_decl_nodiscard mi_decl_export void* mi_recalloc(void* p, size_t newcount, size_t size)  mi_attr_noexcept mi_attr_alloc_size2(2,3);
+
+mi_decl_nodiscard mi_decl_export void* mi_rezalloc_aligned(void* p, size_t newsize, size_t alignment) mi_attr_noexcept mi_attr_alloc_size(2) mi_attr_alloc_align(3);
+mi_decl_nodiscard mi_decl_export void* mi_rezalloc_aligned_at(void* p, size_t newsize, size_t alignment, size_t offset) mi_attr_noexcept mi_attr_alloc_size(2);
+mi_decl_nodiscard mi_decl_export void* mi_recalloc_aligned(void* p, size_t newcount, size_t size, size_t alignment) mi_attr_noexcept mi_attr_alloc_size2(2,3) mi_attr_alloc_align(4);
+mi_decl_nodiscard mi_decl_export void* mi_recalloc_aligned_at(void* p, size_t newcount, size_t size, size_t alignment, size_t offset) mi_attr_noexcept mi_attr_alloc_size2(2,3);
+
+mi_decl_nodiscard mi_decl_export void* mi_heap_rezalloc(mi_heap_t* heap, void* p, size_t newsize)                mi_attr_noexcept mi_attr_alloc_size(3);
+mi_decl_nodiscard mi_decl_export void* mi_heap_recalloc(mi_heap_t* heap, void* p, size_t newcount, size_t size)  mi_attr_noexcept mi_attr_alloc_size2(3,4);
+
+mi_decl_nodiscard mi_decl_export void* mi_heap_rezalloc_aligned(mi_heap_t* heap, void* p, size_t newsize, size_t alignment) mi_attr_noexcept mi_attr_alloc_size(3) mi_attr_alloc_align(4);
+mi_decl_nodiscard mi_decl_export void* mi_heap_rezalloc_aligned_at(mi_heap_t* heap, void* p, size_t newsize, size_t alignment, size_t offset) mi_attr_noexcept mi_attr_alloc_size(3);
+mi_decl_nodiscard mi_decl_export void* mi_heap_recalloc_aligned(mi_heap_t* heap, void* p, size_t newcount, size_t size, size_t alignment) mi_attr_noexcept mi_attr_alloc_size2(3,4) mi_attr_alloc_align(5);
+mi_decl_nodiscard mi_decl_export void* mi_heap_recalloc_aligned_at(mi_heap_t* heap, void* p, size_t newcount, size_t size, size_t alignment, size_t offset) mi_attr_noexcept mi_attr_alloc_size2(3,4);
+
+
+// ------------------------------------------------------
+// Analysis
+// ------------------------------------------------------
+
+mi_decl_export bool mi_heap_contains_block(mi_heap_t* heap, const void* p);
+mi_decl_export bool mi_heap_check_owned(mi_heap_t* heap, const void* p);
+mi_decl_export bool mi_check_owned(const void* p);
+
+// An area of heap space contains blocks of a single size.
+typedef struct mi_heap_area_s {
+  void*  blocks;      // start of the area containing heap blocks
+  size_t reserved;    // bytes reserved for this area (virtual)
+  size_t committed;   // current available bytes for this area
+  size_t used;        // number of allocated blocks
+  size_t block_size;  // size in bytes of each block
+  size_t full_block_size; // size in bytes of a full block including padding and metadata.
+} mi_heap_area_t;
+
+typedef bool (mi_cdecl mi_block_visit_fun)(const mi_heap_t* heap, const mi_heap_area_t* area, void* block, size_t block_size, void* arg);
+
+mi_decl_export bool mi_heap_visit_blocks(const mi_heap_t* heap, bool visit_all_blocks, mi_block_visit_fun* visitor, void* arg);
+
+// Experimental
+mi_decl_nodiscard mi_decl_export bool mi_is_in_heap_region(const void* p) mi_attr_noexcept;
+mi_decl_nodiscard mi_decl_export bool mi_is_redirected(void) mi_attr_noexcept;
+
+mi_decl_export int mi_reserve_huge_os_pages_interleave(size_t pages, size_t numa_nodes, size_t timeout_msecs) mi_attr_noexcept;
+mi_decl_export int mi_reserve_huge_os_pages_at(size_t pages, int numa_node, size_t timeout_msecs) mi_attr_noexcept;
+
+mi_decl_export int  mi_reserve_os_memory(size_t size, bool commit, bool allow_large) mi_attr_noexcept;
+mi_decl_export bool mi_manage_os_memory(void* start, size_t size, bool is_committed, bool is_large, bool is_zero, int numa_node) mi_attr_noexcept;
+
+mi_decl_export void mi_debug_show_arenas(void) mi_attr_noexcept;
+
+// Experimental: heaps associated with specific memory arena's
+typedef int mi_arena_id_t;
+mi_decl_export void* mi_arena_area(mi_arena_id_t arena_id, size_t* size);
+mi_decl_export int   mi_reserve_huge_os_pages_at_ex(size_t pages, int numa_node, size_t timeout_msecs, bool exclusive, mi_arena_id_t* arena_id) mi_attr_noexcept;
+mi_decl_export int   mi_reserve_os_memory_ex(size_t size, bool commit, bool allow_large, bool exclusive, mi_arena_id_t* arena_id) mi_attr_noexcept;
+mi_decl_export bool  mi_manage_os_memory_ex(void* start, size_t size, bool is_committed, bool is_large, bool is_zero, int numa_node, bool exclusive, mi_arena_id_t* arena_id) mi_attr_noexcept;
+
+#if MI_MALLOC_VERSION >= 182
+// Create a heap that only allocates in the specified arena
+mi_decl_nodiscard mi_decl_export mi_heap_t* mi_heap_new_in_arena(mi_arena_id_t arena_id);
+#endif
+
+// deprecated
+mi_decl_export int  mi_reserve_huge_os_pages(size_t pages, double max_secs, size_t* pages_reserved) mi_attr_noexcept;
+
+
+// ------------------------------------------------------
+// Convenience
+// ------------------------------------------------------
+
+#define mi_malloc_tp(tp)                ((tp*)mi_malloc(sizeof(tp)))
+#define mi_zalloc_tp(tp)                ((tp*)mi_zalloc(sizeof(tp)))
+#define mi_calloc_tp(tp,n)              ((tp*)mi_calloc(n,sizeof(tp)))
+#define mi_mallocn_tp(tp,n)             ((tp*)mi_mallocn(n,sizeof(tp)))
+#define mi_reallocn_tp(p,tp,n)          ((tp*)mi_reallocn(p,n,sizeof(tp)))
+#define mi_recalloc_tp(p,tp,n)          ((tp*)mi_recalloc(p,n,sizeof(tp)))
+
+#define mi_heap_malloc_tp(hp,tp)        ((tp*)mi_heap_malloc(hp,sizeof(tp)))
+#define mi_heap_zalloc_tp(hp,tp)        ((tp*)mi_heap_zalloc(hp,sizeof(tp)))
+#define mi_heap_calloc_tp(hp,tp,n)      ((tp*)mi_heap_calloc(hp,n,sizeof(tp)))
+#define mi_heap_mallocn_tp(hp,tp,n)     ((tp*)mi_heap_mallocn(hp,n,sizeof(tp)))
+#define mi_heap_reallocn_tp(hp,p,tp,n)  ((tp*)mi_heap_reallocn(hp,p,n,sizeof(tp)))
+#define mi_heap_recalloc_tp(hp,p,tp,n)  ((tp*)mi_heap_recalloc(hp,p,n,sizeof(tp)))
+
+
+// ------------------------------------------------------
+// Options
+// ------------------------------------------------------
+
+typedef enum mi_option_e {
+  // stable options
+  mi_option_show_errors,              // print error messages
+  mi_option_show_stats,               // print statistics on termination
+  mi_option_verbose,                  // print verbose messages
+  // the following options are experimental (see src/options.h)
+  mi_option_eager_commit,             // eager commit segments? (after `eager_commit_delay` segments) (=1)
+  mi_option_arena_eager_commit,       // eager commit arenas? Use 2 to enable just on overcommit systems (=2)
+  mi_option_purge_decommits,          // should a memory purge decommit (or only reset) (=1)
+  mi_option_allow_large_os_pages,     // allow large (2MiB) OS pages, implies eager commit
+  mi_option_reserve_huge_os_pages,    // reserve N huge OS pages (1GiB/page) at startup
+  mi_option_reserve_huge_os_pages_at, // reserve huge OS pages at a specific NUMA node
+  mi_option_reserve_os_memory,        // reserve specified amount of OS memory in an arena at startup
+  mi_option_deprecated_segment_cache,
+  mi_option_deprecated_page_reset,
+  mi_option_abandoned_page_purge,     // immediately purge delayed purges on thread termination
+  mi_option_deprecated_segment_reset,
+  mi_option_eager_commit_delay,
+  mi_option_purge_delay,              // memory purging is delayed by N milli seconds; use 0 for immediate purging or -1 for no purging at all.
+  mi_option_use_numa_nodes,           // 0 = use all available numa nodes, otherwise use at most N nodes.
+  mi_option_limit_os_alloc,           // 1 = do not use OS memory for allocation (but only programmatically reserved arenas)
+  mi_option_os_tag,                   // tag used for OS logging (macOS only for now)
+  mi_option_max_errors,               // issue at most N error messages
+  mi_option_max_warnings,             // issue at most N warning messages
+  mi_option_max_segment_reclaim,
+  mi_option_destroy_on_exit,          // if set, release all memory on exit; sometimes used for dynamic unloading but can be unsafe.
+  mi_option_arena_reserve,            // initial memory size in KiB for arena reservation (1GiB on 64-bit)
+  mi_option_arena_purge_mult,
+  mi_option_purge_extend_delay,
+  _mi_option_last,
+  // legacy option names
+  mi_option_large_os_pages = mi_option_allow_large_os_pages,
+  mi_option_eager_region_commit = mi_option_arena_eager_commit,
+  mi_option_reset_decommits = mi_option_purge_decommits,
+  mi_option_reset_delay = mi_option_purge_delay,
+  mi_option_abandoned_page_reset = mi_option_abandoned_page_purge
+} mi_option_t;
+
+
+mi_decl_nodiscard mi_decl_export bool mi_option_is_enabled(mi_option_t option);
+mi_decl_export void mi_option_enable(mi_option_t option);
+mi_decl_export void mi_option_disable(mi_option_t option);
+mi_decl_export void mi_option_set_enabled(mi_option_t option, bool enable);
+mi_decl_export void mi_option_set_enabled_default(mi_option_t option, bool enable);
+
+mi_decl_nodiscard mi_decl_export long   mi_option_get(mi_option_t option);
+mi_decl_nodiscard mi_decl_export long   mi_option_get_clamp(mi_option_t option, long min, long max);
+mi_decl_nodiscard mi_decl_export size_t mi_option_get_size(mi_option_t option);
+mi_decl_export void mi_option_set(mi_option_t option, long value);
+mi_decl_export void mi_option_set_default(mi_option_t option, long value);
+
+
+// -------------------------------------------------------------------------------------------------------
+// "mi" prefixed implementations of various posix, Unix, Windows, and C++ allocation functions.
+// (This can be convenient when providing overrides of these functions as done in `mimalloc-override.h`.)
+// note: we use `mi_cfree` as "checked free" and it checks if the pointer is in our heap before free-ing.
+// -------------------------------------------------------------------------------------------------------
+
+mi_decl_export void  mi_cfree(void* p) mi_attr_noexcept;
+mi_decl_export void* mi__expand(void* p, size_t newsize) mi_attr_noexcept;
+mi_decl_nodiscard mi_decl_export size_t mi_malloc_size(const void* p)        mi_attr_noexcept;
+mi_decl_nodiscard mi_decl_export size_t mi_malloc_good_size(size_t size)     mi_attr_noexcept;
+mi_decl_nodiscard mi_decl_export size_t mi_malloc_usable_size(const void *p) mi_attr_noexcept;
+
+mi_decl_export int mi_posix_memalign(void** p, size_t alignment, size_t size)   mi_attr_noexcept;
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_memalign(size_t alignment, size_t size) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(2) mi_attr_alloc_align(1);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_valloc(size_t size)  mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(1);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_pvalloc(size_t size) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(1);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_aligned_alloc(size_t alignment, size_t size) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(2) mi_attr_alloc_align(1);
+
+mi_decl_nodiscard mi_decl_export void* mi_reallocarray(void* p, size_t count, size_t size) mi_attr_noexcept mi_attr_alloc_size2(2,3);
+mi_decl_nodiscard mi_decl_export int   mi_reallocarr(void* p, size_t count, size_t size) mi_attr_noexcept;
+mi_decl_nodiscard mi_decl_export void* mi_aligned_recalloc(void* p, size_t newcount, size_t size, size_t alignment) mi_attr_noexcept;
+mi_decl_nodiscard mi_decl_export void* mi_aligned_offset_recalloc(void* p, size_t newcount, size_t size, size_t alignment, size_t offset) mi_attr_noexcept;
+
+mi_decl_nodiscard mi_decl_export mi_decl_restrict unsigned short* mi_wcsdup(const unsigned short* s) mi_attr_noexcept mi_attr_malloc;
+mi_decl_nodiscard mi_decl_export mi_decl_restrict unsigned char*  mi_mbsdup(const unsigned char* s)  mi_attr_noexcept mi_attr_malloc;
+mi_decl_export int mi_dupenv_s(char** buf, size_t* size, const char* name)                      mi_attr_noexcept;
+mi_decl_export int mi_wdupenv_s(unsigned short** buf, size_t* size, const unsigned short* name) mi_attr_noexcept;
+
+mi_decl_export void mi_free_size(void* p, size_t size)                           mi_attr_noexcept;
+mi_decl_export void mi_free_size_aligned(void* p, size_t size, size_t alignment) mi_attr_noexcept;
+mi_decl_export void mi_free_aligned(void* p, size_t alignment)                   mi_attr_noexcept;
+
+// The `mi_new` wrappers implement C++ semantics on out-of-memory instead of directly returning `NULL`.
+// (and call `std::get_new_handler` and potentially raise a `std::bad_alloc` exception).
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_new(size_t size)                   mi_attr_malloc mi_attr_alloc_size(1);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_new_aligned(size_t size, size_t alignment) mi_attr_malloc mi_attr_alloc_size(1) mi_attr_alloc_align(2);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_new_nothrow(size_t size)           mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(1);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_new_aligned_nothrow(size_t size, size_t alignment) mi_attr_noexcept mi_attr_malloc mi_attr_alloc_size(1) mi_attr_alloc_align(2);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_new_n(size_t count, size_t size)   mi_attr_malloc mi_attr_alloc_size2(1, 2);
+mi_decl_nodiscard mi_decl_export void* mi_new_realloc(void* p, size_t newsize)                mi_attr_alloc_size(2);
+mi_decl_nodiscard mi_decl_export void* mi_new_reallocn(void* p, size_t newcount, size_t size) mi_attr_alloc_size2(2, 3);
+
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_heap_alloc_new(mi_heap_t* heap, size_t size)                mi_attr_malloc mi_attr_alloc_size(2);
+mi_decl_nodiscard mi_decl_export mi_decl_restrict void* mi_heap_alloc_new_n(mi_heap_t* heap, size_t count, size_t size) mi_attr_malloc mi_attr_alloc_size2(2, 3);
+
+#ifdef __cplusplus
+}
+#endif
+
+// ---------------------------------------------------------------------------------------------
+// Implement the C++ std::allocator interface for use in STL containers.
+// (note: see `mimalloc-new-delete.h` for overriding the new/delete operators globally)
+// ---------------------------------------------------------------------------------------------
+#ifdef __cplusplus
+
+#include <cstddef>     // std::size_t
+#include <cstdint>     // PTRDIFF_MAX
+#if (__cplusplus >= 201103L) || (_MSC_VER > 1900)  // C++11
+#include <type_traits> // std::true_type
+#include <utility>     // std::forward
+#endif
+
+template<class T> struct _mi_stl_allocator_common {
+  typedef T                 value_type;
+  typedef std::size_t       size_type;
+  typedef std::ptrdiff_t    difference_type;
+  typedef value_type&       reference;
+  typedef value_type const& const_reference;
+  typedef value_type*       pointer;
+  typedef value_type const* const_pointer;
+
+  #if ((__cplusplus >= 201103L) || (_MSC_VER > 1900))  // C++11
+  using propagate_on_container_copy_assignment = std::true_type;
+  using propagate_on_container_move_assignment = std::true_type;
+  using propagate_on_container_swap            = std::true_type;
+  template <class U, class ...Args> void construct(U* p, Args&& ...args) { ::new(p) U(std::forward<Args>(args)...); }
+  template <class U> void destroy(U* p) mi_attr_noexcept { p->~U(); }
+  #else
+  void construct(pointer p, value_type const& val) { ::new(p) value_type(val); }
+  void destroy(pointer p) { p->~value_type(); }
+  #endif
+
+  size_type     max_size() const mi_attr_noexcept { return (PTRDIFF_MAX/sizeof(value_type)); }
+  pointer       address(reference x) const        { return &x; }
+  const_pointer address(const_reference x) const  { return &x; }
+};
+
+template<class T> struct mi_stl_allocator : public _mi_stl_allocator_common<T> {
+  using typename _mi_stl_allocator_common<T>::size_type;
+  using typename _mi_stl_allocator_common<T>::value_type;
+  using typename _mi_stl_allocator_common<T>::pointer;
+  template <class U> struct rebind { typedef mi_stl_allocator<U> other; };
+
+  mi_stl_allocator()                                             mi_attr_noexcept = default;
+  mi_stl_allocator(const mi_stl_allocator&)                      mi_attr_noexcept = default;
+  template<class U> mi_stl_allocator(const mi_stl_allocator<U>&) mi_attr_noexcept { }
+  mi_stl_allocator  select_on_container_copy_construction() const { return *this; }
+  void              deallocate(T* p, size_type) { mi_free(p); }
+
+  #if (__cplusplus >= 201703L)  // C++17
+  mi_decl_nodiscard T* allocate(size_type count) { return static_cast<T*>(mi_new_n(count, sizeof(T))); }
+  mi_decl_nodiscard T* allocate(size_type count, const void*) { return allocate(count); }
+  #else
+  mi_decl_nodiscard pointer allocate(size_type count, const void* = 0) { return static_cast<pointer>(mi_new_n(count, sizeof(value_type))); }
+  #endif
+
+  #if ((__cplusplus >= 201103L) || (_MSC_VER > 1900))  // C++11
+  using is_always_equal = std::true_type;
+  #endif
+};
+
+template<class T1,class T2> bool operator==(const mi_stl_allocator<T1>& , const mi_stl_allocator<T2>& ) mi_attr_noexcept { return true; }
+template<class T1,class T2> bool operator!=(const mi_stl_allocator<T1>& , const mi_stl_allocator<T2>& ) mi_attr_noexcept { return false; }
+
+
+#if (__cplusplus >= 201103L) || (_MSC_VER >= 1900)  // C++11
+#define MI_HAS_HEAP_STL_ALLOCATOR 1
+
+#include <memory>      // std::shared_ptr
+
+// Common base class for STL allocators in a specific heap
+template<class T, bool _mi_destroy> struct _mi_heap_stl_allocator_common : public _mi_stl_allocator_common<T> {
+  using typename _mi_stl_allocator_common<T>::size_type;
+  using typename _mi_stl_allocator_common<T>::value_type;
+  using typename _mi_stl_allocator_common<T>::pointer;
+
+  _mi_heap_stl_allocator_common(mi_heap_t* hp) : heap(hp) { }    /* will not delete nor destroy the passed in heap */
+
+  #if (__cplusplus >= 201703L)  // C++17
+  mi_decl_nodiscard T* allocate(size_type count) { return static_cast<T*>(mi_heap_alloc_new_n(this->heap.get(), count, sizeof(T))); }
+  mi_decl_nodiscard T* allocate(size_type count, const void*) { return allocate(count); }
+  #else
+  mi_decl_nodiscard pointer allocate(size_type count, const void* = 0) { return static_cast<pointer>(mi_heap_alloc_new_n(this->heap.get(), count, sizeof(value_type))); }
+  #endif
+
+  #if ((__cplusplus >= 201103L) || (_MSC_VER > 1900))  // C++11
+  using is_always_equal = std::false_type;
+  #endif
+
+  void collect(bool force) { mi_heap_collect(this->heap.get(), force); }
+  template<class U> bool is_equal(const _mi_heap_stl_allocator_common<U, _mi_destroy>& x) const { return (this->heap == x.heap); }
+
+protected:
+  std::shared_ptr<mi_heap_t> heap;
+  template<class U, bool D> friend struct _mi_heap_stl_allocator_common;
+
+  _mi_heap_stl_allocator_common() {
+    mi_heap_t* hp = mi_heap_new();
+    this->heap.reset(hp, (_mi_destroy ? &heap_destroy : &heap_delete));  /* calls heap_delete/destroy when the refcount drops to zero */
+  }
+  _mi_heap_stl_allocator_common(const _mi_heap_stl_allocator_common& x) mi_attr_noexcept : heap(x.heap) { }
+  template<class U> _mi_heap_stl_allocator_common(const _mi_heap_stl_allocator_common<U, _mi_destroy>& x) mi_attr_noexcept : heap(x.heap) { }
+
+private:
+  static void heap_delete(mi_heap_t* hp)  { if (hp != NULL) { mi_heap_delete(hp); } }
+  static void heap_destroy(mi_heap_t* hp) { if (hp != NULL) { mi_heap_destroy(hp); } }
+};
+
+// STL allocator allocation in a specific heap
+template<class T> struct mi_heap_stl_allocator : public _mi_heap_stl_allocator_common<T, false> {
+  using typename _mi_heap_stl_allocator_common<T, false>::size_type;
+  mi_heap_stl_allocator() : _mi_heap_stl_allocator_common<T, false>() { } // creates fresh heap that is deleted when the destructor is called
+  mi_heap_stl_allocator(mi_heap_t* hp) : _mi_heap_stl_allocator_common<T, false>(hp) { }  // no delete nor destroy on the passed in heap
+  template<class U> mi_heap_stl_allocator(const mi_heap_stl_allocator<U>& x) mi_attr_noexcept : _mi_heap_stl_allocator_common<T, false>(x) { }
+
+  mi_heap_stl_allocator select_on_container_copy_construction() const { return *this; }
+  void deallocate(T* p, size_type) { mi_free(p); }
+  template<class U> struct rebind { typedef mi_heap_stl_allocator<U> other; };
+};
+
+template<class T1, class T2> bool operator==(const mi_heap_stl_allocator<T1>& x, const mi_heap_stl_allocator<T2>& y) mi_attr_noexcept { return (x.is_equal(y)); }
+template<class T1, class T2> bool operator!=(const mi_heap_stl_allocator<T1>& x, const mi_heap_stl_allocator<T2>& y) mi_attr_noexcept { return (!x.is_equal(y)); }
+
+
+// STL allocator allocation in a specific heap, where `free` does nothing and
+// the heap is destroyed in one go on destruction -- use with care!
+template<class T> struct mi_heap_destroy_stl_allocator : public _mi_heap_stl_allocator_common<T, true> {
+  using typename _mi_heap_stl_allocator_common<T, true>::size_type;
+  mi_heap_destroy_stl_allocator() : _mi_heap_stl_allocator_common<T, true>() { } // creates fresh heap that is destroyed when the destructor is called
+  mi_heap_destroy_stl_allocator(mi_heap_t* hp) : _mi_heap_stl_allocator_common<T, true>(hp) { }  // no delete nor destroy on the passed in heap
+  template<class U> mi_heap_destroy_stl_allocator(const mi_heap_destroy_stl_allocator<U>& x) mi_attr_noexcept : _mi_heap_stl_allocator_common<T, true>(x) { }
+
+  mi_heap_destroy_stl_allocator select_on_container_copy_construction() const { return *this; }
+  void deallocate(T*, size_type) { /* do nothing as we destroy the heap on destruct. */ }
+  template<class U> struct rebind { typedef mi_heap_destroy_stl_allocator<U> other; };
+};
+
+template<class T1, class T2> bool operator==(const mi_heap_destroy_stl_allocator<T1>& x, const mi_heap_destroy_stl_allocator<T2>& y) mi_attr_noexcept { return (x.is_equal(y)); }
+template<class T1, class T2> bool operator!=(const mi_heap_destroy_stl_allocator<T1>& x, const mi_heap_destroy_stl_allocator<T2>& y) mi_attr_noexcept { return (!x.is_equal(y)); }
+
+#endif // C++11
+
+#endif // __cplusplus
+
+#endif
diff --git a/compat/mimalloc/mimalloc/atomic.h b/compat/mimalloc/mimalloc/atomic.h
new file mode 100644
index 00000000000000..c6b8146ffdb049
--- /dev/null
+++ b/compat/mimalloc/mimalloc/atomic.h
@@ -0,0 +1,385 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2023 Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+#pragma once
+#ifndef MIMALLOC_ATOMIC_H
+#define MIMALLOC_ATOMIC_H
+
+// --------------------------------------------------------------------------------------------
+// Atomics
+// We need to be portable between C, C++, and MSVC.
+// We base the primitives on the C/C++ atomics and create a mimimal wrapper for MSVC in C compilation mode.
+// This is why we try to use only `uintptr_t` and `<type>*` as atomic types.
+// To gain better insight in the range of used atomics, we use explicitly named memory order operations
+// instead of passing the memory order as a parameter.
+// -----------------------------------------------------------------------------------------------
+
+#if defined(__cplusplus)
+// Use C++ atomics
+#include <atomic>
+#define  _Atomic(tp)            std::atomic<tp>
+#define  mi_atomic(name)        std::atomic_##name
+#define  mi_memory_order(name)  std::memory_order_##name
+#if !defined(ATOMIC_VAR_INIT) || (__cplusplus >= 202002L) // c++20, see issue #571
+ #define MI_ATOMIC_VAR_INIT(x)  x
+#else
+ #define MI_ATOMIC_VAR_INIT(x)  ATOMIC_VAR_INIT(x)
+#endif
+#elif defined(_MSC_VER)
+// Use MSVC C wrapper for C11 atomics
+#define  _Atomic(tp)            tp
+#define  MI_ATOMIC_VAR_INIT(x)  x
+#define  mi_atomic(name)        mi_atomic_##name
+#define  mi_memory_order(name)  mi_memory_order_##name
+#else
+// Use C11 atomics
+#include <stdatomic.h>
+#define  mi_atomic(name)        atomic_##name
+#define  mi_memory_order(name)  memory_order_##name
+#if !defined(ATOMIC_VAR_INIT) || (__STDC_VERSION__ >= 201710L) // c17, see issue #735
+ #define MI_ATOMIC_VAR_INIT(x) x
+#else
+ #define MI_ATOMIC_VAR_INIT(x) ATOMIC_VAR_INIT(x)
+#endif
+#endif
+
+// Various defines for all used memory orders in mimalloc
+#define mi_atomic_cas_weak(p,expected,desired,mem_success,mem_fail)  \
+  mi_atomic(compare_exchange_weak_explicit)(p,expected,desired,mem_success,mem_fail)
+
+#define mi_atomic_cas_strong(p,expected,desired,mem_success,mem_fail)  \
+  mi_atomic(compare_exchange_strong_explicit)(p,expected,desired,mem_success,mem_fail)
+
+#define mi_atomic_load_acquire(p)                mi_atomic(load_explicit)(p,mi_memory_order(acquire))
+#define mi_atomic_load_relaxed(p)                mi_atomic(load_explicit)(p,mi_memory_order(relaxed))
+#define mi_atomic_store_release(p,x)             mi_atomic(store_explicit)(p,x,mi_memory_order(release))
+#define mi_atomic_store_relaxed(p,x)             mi_atomic(store_explicit)(p,x,mi_memory_order(relaxed))
+#define mi_atomic_exchange_release(p,x)          mi_atomic(exchange_explicit)(p,x,mi_memory_order(release))
+#define mi_atomic_exchange_acq_rel(p,x)          mi_atomic(exchange_explicit)(p,x,mi_memory_order(acq_rel))
+#define mi_atomic_cas_weak_release(p,exp,des)    mi_atomic_cas_weak(p,exp,des,mi_memory_order(release),mi_memory_order(relaxed))
+#define mi_atomic_cas_weak_acq_rel(p,exp,des)    mi_atomic_cas_weak(p,exp,des,mi_memory_order(acq_rel),mi_memory_order(acquire))
+#define mi_atomic_cas_strong_release(p,exp,des)  mi_atomic_cas_strong(p,exp,des,mi_memory_order(release),mi_memory_order(relaxed))
+#define mi_atomic_cas_strong_acq_rel(p,exp,des)  mi_atomic_cas_strong(p,exp,des,mi_memory_order(acq_rel),mi_memory_order(acquire))
+
+#define mi_atomic_add_relaxed(p,x)               mi_atomic(fetch_add_explicit)(p,x,mi_memory_order(relaxed))
+#define mi_atomic_sub_relaxed(p,x)               mi_atomic(fetch_sub_explicit)(p,x,mi_memory_order(relaxed))
+#define mi_atomic_add_acq_rel(p,x)               mi_atomic(fetch_add_explicit)(p,x,mi_memory_order(acq_rel))
+#define mi_atomic_sub_acq_rel(p,x)               mi_atomic(fetch_sub_explicit)(p,x,mi_memory_order(acq_rel))
+#define mi_atomic_and_acq_rel(p,x)               mi_atomic(fetch_and_explicit)(p,x,mi_memory_order(acq_rel))
+#define mi_atomic_or_acq_rel(p,x)                mi_atomic(fetch_or_explicit)(p,x,mi_memory_order(acq_rel))
+
+#define mi_atomic_increment_relaxed(p)           mi_atomic_add_relaxed(p,(uintptr_t)1)
+#define mi_atomic_decrement_relaxed(p)           mi_atomic_sub_relaxed(p,(uintptr_t)1)
+#define mi_atomic_increment_acq_rel(p)           mi_atomic_add_acq_rel(p,(uintptr_t)1)
+#define mi_atomic_decrement_acq_rel(p)           mi_atomic_sub_acq_rel(p,(uintptr_t)1)
+
+static inline void mi_atomic_yield(void);
+static inline intptr_t mi_atomic_addi(_Atomic(intptr_t)*p, intptr_t add);
+static inline intptr_t mi_atomic_subi(_Atomic(intptr_t)*p, intptr_t sub);
+
+
+#if defined(__cplusplus) || !defined(_MSC_VER)
+
+// In C++/C11 atomics we have polymorphic atomics so can use the typed `ptr` variants (where `tp` is the type of atomic value)
+// We use these macros so we can provide a typed wrapper in MSVC in C compilation mode as well
+#define mi_atomic_load_ptr_acquire(tp,p)                mi_atomic_load_acquire(p)
+#define mi_atomic_load_ptr_relaxed(tp,p)                mi_atomic_load_relaxed(p)
+
+// In C++ we need to add casts to help resolve templates if NULL is passed
+#if defined(__cplusplus)
+#define mi_atomic_store_ptr_release(tp,p,x)             mi_atomic_store_release(p,(tp*)x)
+#define mi_atomic_store_ptr_relaxed(tp,p,x)             mi_atomic_store_relaxed(p,(tp*)x)
+#define mi_atomic_cas_ptr_weak_release(tp,p,exp,des)    mi_atomic_cas_weak_release(p,exp,(tp*)des)
+#define mi_atomic_cas_ptr_weak_acq_rel(tp,p,exp,des)    mi_atomic_cas_weak_acq_rel(p,exp,(tp*)des)
+#define mi_atomic_cas_ptr_strong_release(tp,p,exp,des)  mi_atomic_cas_strong_release(p,exp,(tp*)des)
+#define mi_atomic_exchange_ptr_release(tp,p,x)          mi_atomic_exchange_release(p,(tp*)x)
+#define mi_atomic_exchange_ptr_acq_rel(tp,p,x)          mi_atomic_exchange_acq_rel(p,(tp*)x)
+#else
+#define mi_atomic_store_ptr_release(tp,p,x)             mi_atomic_store_release(p,x)
+#define mi_atomic_store_ptr_relaxed(tp,p,x)             mi_atomic_store_relaxed(p,x)
+#define mi_atomic_cas_ptr_weak_release(tp,p,exp,des)    mi_atomic_cas_weak_release(p,exp,des)
+#define mi_atomic_cas_ptr_weak_acq_rel(tp,p,exp,des)    mi_atomic_cas_weak_acq_rel(p,exp,des)
+#define mi_atomic_cas_ptr_strong_release(tp,p,exp,des)  mi_atomic_cas_strong_release(p,exp,des)
+#define mi_atomic_exchange_ptr_release(tp,p,x)          mi_atomic_exchange_release(p,x)
+#define mi_atomic_exchange_ptr_acq_rel(tp,p,x)          mi_atomic_exchange_acq_rel(p,x)
+#endif
+
+// These are used by the statistics
+static inline int64_t mi_atomic_addi64_relaxed(volatile int64_t* p, int64_t add) {
+  return mi_atomic(fetch_add_explicit)((_Atomic(int64_t)*)p, add, mi_memory_order(relaxed));
+}
+static inline void mi_atomic_maxi64_relaxed(volatile int64_t* p, int64_t x) {
+  int64_t current = mi_atomic_load_relaxed((_Atomic(int64_t)*)p);
+  while (current < x && !mi_atomic_cas_weak_release((_Atomic(int64_t)*)p, &current, x)) { /* nothing */ };
+}
+
+// Used by timers
+#define mi_atomic_loadi64_acquire(p)            mi_atomic(load_explicit)(p,mi_memory_order(acquire))
+#define mi_atomic_loadi64_relaxed(p)            mi_atomic(load_explicit)(p,mi_memory_order(relaxed))
+#define mi_atomic_storei64_release(p,x)         mi_atomic(store_explicit)(p,x,mi_memory_order(release))
+#define mi_atomic_storei64_relaxed(p,x)         mi_atomic(store_explicit)(p,x,mi_memory_order(relaxed))
+
+#define mi_atomic_casi64_strong_acq_rel(p,e,d)  mi_atomic_cas_strong_acq_rel(p,e,d)
+#define mi_atomic_addi64_acq_rel(p,i)           mi_atomic_add_acq_rel(p,i)
+
+
+#elif defined(_MSC_VER)
+
+// MSVC C compilation wrapper that uses Interlocked operations to model C11 atomics.
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#include <intrin.h>
+#ifdef _WIN64
+typedef LONG64   msc_intptr_t;
+#define MI_64(f) f##64
+#else
+typedef LONG     msc_intptr_t;
+#define MI_64(f) f
+#endif
+
+typedef enum mi_memory_order_e {
+  mi_memory_order_relaxed,
+  mi_memory_order_consume,
+  mi_memory_order_acquire,
+  mi_memory_order_release,
+  mi_memory_order_acq_rel,
+  mi_memory_order_seq_cst
+} mi_memory_order;
+
+static inline uintptr_t mi_atomic_fetch_add_explicit(_Atomic(uintptr_t)*p, uintptr_t add, mi_memory_order mo) {
+  (void)(mo);
+  return (uintptr_t)MI_64(_InterlockedExchangeAdd)((volatile msc_intptr_t*)p, (msc_intptr_t)add);
+}
+static inline uintptr_t mi_atomic_fetch_sub_explicit(_Atomic(uintptr_t)*p, uintptr_t sub, mi_memory_order mo) {
+  (void)(mo);
+  return (uintptr_t)MI_64(_InterlockedExchangeAdd)((volatile msc_intptr_t*)p, -((msc_intptr_t)sub));
+}
+static inline uintptr_t mi_atomic_fetch_and_explicit(_Atomic(uintptr_t)*p, uintptr_t x, mi_memory_order mo) {
+  (void)(mo);
+  return (uintptr_t)MI_64(_InterlockedAnd)((volatile msc_intptr_t*)p, (msc_intptr_t)x);
+}
+static inline uintptr_t mi_atomic_fetch_or_explicit(_Atomic(uintptr_t)*p, uintptr_t x, mi_memory_order mo) {
+  (void)(mo);
+  return (uintptr_t)MI_64(_InterlockedOr)((volatile msc_intptr_t*)p, (msc_intptr_t)x);
+}
+static inline bool mi_atomic_compare_exchange_strong_explicit(_Atomic(uintptr_t)*p, uintptr_t* expected, uintptr_t desired, mi_memory_order mo1, mi_memory_order mo2) {
+  (void)(mo1); (void)(mo2);
+  uintptr_t read = (uintptr_t)MI_64(_InterlockedCompareExchange)((volatile msc_intptr_t*)p, (msc_intptr_t)desired, (msc_intptr_t)(*expected));
+  if (read == *expected) {
+    return true;
+  }
+  else {
+    *expected = read;
+    return false;
+  }
+}
+static inline bool mi_atomic_compare_exchange_weak_explicit(_Atomic(uintptr_t)*p, uintptr_t* expected, uintptr_t desired, mi_memory_order mo1, mi_memory_order mo2) {
+  return mi_atomic_compare_exchange_strong_explicit(p, expected, desired, mo1, mo2);
+}
+static inline uintptr_t mi_atomic_exchange_explicit(_Atomic(uintptr_t)*p, uintptr_t exchange, mi_memory_order mo) {
+  (void)(mo);
+  return (uintptr_t)MI_64(_InterlockedExchange)((volatile msc_intptr_t*)p, (msc_intptr_t)exchange);
+}
+static inline void mi_atomic_thread_fence(mi_memory_order mo) {
+  (void)(mo);
+  _Atomic(uintptr_t) x = 0;
+  mi_atomic_exchange_explicit(&x, 1, mo);
+}
+static inline uintptr_t mi_atomic_load_explicit(_Atomic(uintptr_t) const* p, mi_memory_order mo) {
+  (void)(mo);
+#if defined(_M_IX86) || defined(_M_X64)
+  return *p;
+#else
+  uintptr_t x = *p;
+  if (mo > mi_memory_order_relaxed) {
+    while (!mi_atomic_compare_exchange_weak_explicit(p, &x, x, mo, mi_memory_order_relaxed)) { /* nothing */ };
+  }
+  return x;
+#endif
+}
+static inline void mi_atomic_store_explicit(_Atomic(uintptr_t)*p, uintptr_t x, mi_memory_order mo) {
+  (void)(mo);
+#if defined(_M_IX86) || defined(_M_X64)
+  *p = x;
+#else
+  mi_atomic_exchange_explicit(p, x, mo);
+#endif
+}
+static inline int64_t mi_atomic_loadi64_explicit(_Atomic(int64_t)*p, mi_memory_order mo) {
+  (void)(mo);
+#if defined(_M_X64)
+  return *p;
+#else
+  int64_t old = *p;
+  int64_t x = old;
+  while ((old = InterlockedCompareExchange64(p, x, old)) != x) {
+    x = old;
+  }
+  return x;
+#endif
+}
+static inline void mi_atomic_storei64_explicit(_Atomic(int64_t)*p, int64_t x, mi_memory_order mo) {
+  (void)(mo);
+#if defined(x_M_IX86) || defined(_M_X64)
+  *p = x;
+#else
+  InterlockedExchange64(p, x);
+#endif
+}
+
+// These are used by the statistics
+static inline int64_t mi_atomic_addi64_relaxed(volatile _Atomic(int64_t)*p, int64_t add) {
+#ifdef _WIN64
+  return (int64_t)mi_atomic_addi((int64_t*)p, add);
+#else
+  int64_t current;
+  int64_t sum;
+  do {
+    current = *p;
+    sum = current + add;
+  } while (_InterlockedCompareExchange64(p, sum, current) != current);
+  return current;
+#endif
+}
+static inline void mi_atomic_maxi64_relaxed(volatile _Atomic(int64_t)*p, int64_t x) {
+  int64_t current;
+  do {
+    current = *p;
+  } while (current < x && _InterlockedCompareExchange64(p, x, current) != current);
+}
+
+static inline void mi_atomic_addi64_acq_rel(volatile _Atomic(int64_t*)p, int64_t i) {
+  mi_atomic_addi64_relaxed(p, i);
+}
+
+static inline bool mi_atomic_casi64_strong_acq_rel(volatile _Atomic(int64_t*)p, int64_t* exp, int64_t des) {
+  int64_t read = _InterlockedCompareExchange64(p, des, *exp);
+  if (read == *exp) {
+    return true;
+  }
+  else {
+    *exp = read;
+    return false;
+  }
+}
+
+// The pointer macros cast to `uintptr_t`.
+#define mi_atomic_load_ptr_acquire(tp,p)                (tp*)mi_atomic_load_acquire((_Atomic(uintptr_t)*)(p))
+#define mi_atomic_load_ptr_relaxed(tp,p)                (tp*)mi_atomic_load_relaxed((_Atomic(uintptr_t)*)(p))
+#define mi_atomic_store_ptr_release(tp,p,x)             mi_atomic_store_release((_Atomic(uintptr_t)*)(p),(uintptr_t)(x))
+#define mi_atomic_store_ptr_relaxed(tp,p,x)             mi_atomic_store_relaxed((_Atomic(uintptr_t)*)(p),(uintptr_t)(x))
+#define mi_atomic_cas_ptr_weak_release(tp,p,exp,des)    mi_atomic_cas_weak_release((_Atomic(uintptr_t)*)(p),(uintptr_t*)exp,(uintptr_t)des)
+#define mi_atomic_cas_ptr_weak_acq_rel(tp,p,exp,des)    mi_atomic_cas_weak_acq_rel((_Atomic(uintptr_t)*)(p),(uintptr_t*)exp,(uintptr_t)des)
+#define mi_atomic_cas_ptr_strong_release(tp,p,exp,des)  mi_atomic_cas_strong_release((_Atomic(uintptr_t)*)(p),(uintptr_t*)exp,(uintptr_t)des)
+#define mi_atomic_exchange_ptr_release(tp,p,x)          (tp*)mi_atomic_exchange_release((_Atomic(uintptr_t)*)(p),(uintptr_t)x)
+#define mi_atomic_exchange_ptr_acq_rel(tp,p,x)          (tp*)mi_atomic_exchange_acq_rel((_Atomic(uintptr_t)*)(p),(uintptr_t)x)
+
+#define mi_atomic_loadi64_acquire(p)    mi_atomic(loadi64_explicit)(p,mi_memory_order(acquire))
+#define mi_atomic_loadi64_relaxed(p)    mi_atomic(loadi64_explicit)(p,mi_memory_order(relaxed))
+#define mi_atomic_storei64_release(p,x) mi_atomic(storei64_explicit)(p,x,mi_memory_order(release))
+#define mi_atomic_storei64_relaxed(p,x) mi_atomic(storei64_explicit)(p,x,mi_memory_order(relaxed))
+
+
+#endif
+
+
+// Atomically add a signed value; returns the previous value.
+static inline intptr_t mi_atomic_addi(_Atomic(intptr_t)*p, intptr_t add) {
+  return (intptr_t)mi_atomic_add_acq_rel((_Atomic(uintptr_t)*)p, (uintptr_t)add);
+}
+
+// Atomically subtract a signed value; returns the previous value.
+static inline intptr_t mi_atomic_subi(_Atomic(intptr_t)*p, intptr_t sub) {
+  return (intptr_t)mi_atomic_addi(p, -sub);
+}
+
+typedef _Atomic(uintptr_t) mi_atomic_once_t;
+
+// Returns true only on the first invocation
+static inline bool mi_atomic_once( mi_atomic_once_t* once ) {
+  if (mi_atomic_load_relaxed(once) != 0) return false;     // quick test
+  uintptr_t expected = 0;
+  return mi_atomic_cas_strong_acq_rel(once, &expected, (uintptr_t)1); // try to set to 1
+}
+
+typedef _Atomic(uintptr_t) mi_atomic_guard_t;
+
+// Allows only one thread to execute at a time
+#define mi_atomic_guard(guard) \
+  uintptr_t _mi_guard_expected = 0; \
+  for(bool _mi_guard_once = true; \
+      _mi_guard_once && mi_atomic_cas_strong_acq_rel(guard,&_mi_guard_expected,(uintptr_t)1); \
+      (mi_atomic_store_release(guard,(uintptr_t)0), _mi_guard_once = false) )
+
+
+
+// Yield
+#if defined(__cplusplus)
+#include <thread>
+static inline void mi_atomic_yield(void) {
+  std::this_thread::yield();
+}
+#elif defined(_WIN32)
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+static inline void mi_atomic_yield(void) {
+  YieldProcessor();
+}
+#elif defined(__SSE2__)
+#include <emmintrin.h>
+static inline void mi_atomic_yield(void) {
+  _mm_pause();
+}
+#elif (defined(__GNUC__) || defined(__clang__)) && \
+      (defined(__x86_64__) || defined(__i386__) || defined(__arm__) || defined(__armel__) || defined(__ARMEL__) || \
+       defined(__aarch64__) || defined(__powerpc__) || defined(__ppc__) || defined(__PPC__)) || defined(__POWERPC__)
+#if defined(__x86_64__) || defined(__i386__)
+static inline void mi_atomic_yield(void) {
+  __asm__ volatile ("pause" ::: "memory");
+}
+#elif defined(__aarch64__)
+static inline void mi_atomic_yield(void) {
+  __asm__ volatile("wfe");
+}
+#elif (defined(__arm__) && __ARM_ARCH__ >= 7)
+static inline void mi_atomic_yield(void) {
+  __asm__ volatile("yield" ::: "memory");
+}
+#elif defined(__powerpc__) || defined(__ppc__) || defined(__PPC__) || defined(__POWERPC__)
+#ifdef __APPLE__
+static inline void mi_atomic_yield(void) {
+  __asm__ volatile ("or r27,r27,r27" ::: "memory");
+}
+#else
+static inline void mi_atomic_yield(void) {
+  __asm__ __volatile__ ("or 27,27,27" ::: "memory");
+}
+#endif
+#elif defined(__armel__) || defined(__ARMEL__)
+static inline void mi_atomic_yield(void) {
+  __asm__ volatile ("nop" ::: "memory");
+}
+#endif
+#elif defined(__sun)
+// Fallback for other archs
+#include <synch.h>
+static inline void mi_atomic_yield(void) {
+  smt_pause();
+}
+#elif defined(__wasi__)
+#include <sched.h>
+static inline void mi_atomic_yield(void) {
+  sched_yield();
+}
+#else
+#include <unistd.h>
+static inline void mi_atomic_yield(void) {
+  sleep(0);
+}
+#endif
+
+
+#endif // __MIMALLOC_ATOMIC_H
diff --git a/compat/mimalloc/mimalloc/internal.h b/compat/mimalloc/mimalloc/internal.h
new file mode 100644
index 00000000000000..f076bc6a40f977
--- /dev/null
+++ b/compat/mimalloc/mimalloc/internal.h
@@ -0,0 +1,979 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2023, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+#pragma once
+#ifndef MIMALLOC_INTERNAL_H
+#define MIMALLOC_INTERNAL_H
+
+
+// --------------------------------------------------------------------------
+// This file contains the interal API's of mimalloc and various utility
+// functions and macros.
+// --------------------------------------------------------------------------
+
+#include "mimalloc/types.h"
+#include "mimalloc/track.h"
+
+#if (MI_DEBUG>0)
+#define mi_trace_message(...)  _mi_trace_message(__VA_ARGS__)
+#else
+#define mi_trace_message(...)
+#endif
+
+#define MI_CACHE_LINE          64
+#if defined(_MSC_VER)
+#pragma warning(disable:4127)   // suppress constant conditional warning (due to MI_SECURE paths)
+#pragma warning(disable:26812)  // unscoped enum warning
+#define mi_decl_noinline        __declspec(noinline)
+#define mi_decl_thread          __declspec(thread)
+#define mi_decl_cache_align     __declspec(align(MI_CACHE_LINE))
+#elif (defined(__GNUC__) && (__GNUC__ >= 3)) || defined(__clang__) // includes clang and icc
+#define mi_decl_noinline        __attribute__((noinline))
+#define mi_decl_thread          __thread
+#define mi_decl_cache_align     __attribute__((aligned(MI_CACHE_LINE)))
+#else
+#define mi_decl_noinline
+#define mi_decl_thread          __thread        // hope for the best :-)
+#define mi_decl_cache_align
+#endif
+
+#if defined(__EMSCRIPTEN__) && !defined(__wasi__)
+#define __wasi__
+#endif
+
+#if defined(__cplusplus)
+#define mi_decl_externc       extern "C"
+#else
+#define mi_decl_externc
+#endif
+
+// pthreads
+#if !defined(_WIN32) && !defined(__wasi__)
+#define  MI_USE_PTHREADS
+#include <pthread.h>
+#endif
+
+// "options.c"
+void       _mi_fputs(mi_output_fun* out, void* arg, const char* prefix, const char* message);
+void       _mi_fprintf(mi_output_fun* out, void* arg, const char* fmt, ...);
+void       _mi_warning_message(const char* fmt, ...);
+void       _mi_verbose_message(const char* fmt, ...);
+void       _mi_trace_message(const char* fmt, ...);
+void       _mi_options_init(void);
+void       _mi_error_message(int err, const char* fmt, ...);
+
+// random.c
+void       _mi_random_init(mi_random_ctx_t* ctx);
+void       _mi_random_init_weak(mi_random_ctx_t* ctx);
+void       _mi_random_reinit_if_weak(mi_random_ctx_t * ctx);
+void       _mi_random_split(mi_random_ctx_t* ctx, mi_random_ctx_t* new_ctx);
+uintptr_t  _mi_random_next(mi_random_ctx_t* ctx);
+uintptr_t  _mi_heap_random_next(mi_heap_t* heap);
+uintptr_t  _mi_os_random_weak(uintptr_t extra_seed);
+static inline uintptr_t _mi_random_shuffle(uintptr_t x);
+
+// init.c
+extern mi_decl_cache_align mi_stats_t       _mi_stats_main;
+extern mi_decl_cache_align const mi_page_t  _mi_page_empty;
+bool       _mi_is_main_thread(void);
+size_t     _mi_current_thread_count(void);
+bool       _mi_preloading(void);           // true while the C runtime is not initialized yet
+mi_threadid_t _mi_thread_id(void) mi_attr_noexcept;
+mi_heap_t*    _mi_heap_main_get(void);     // statically allocated main backing heap
+void       _mi_thread_done(mi_heap_t* heap);
+void       _mi_thread_data_collect(void);
+
+// os.c
+void       _mi_os_init(void);                                            // called from process init
+void*      _mi_os_alloc(size_t size, mi_memid_t* memid, mi_stats_t* stats);
+void       _mi_os_free(void* p, size_t size, mi_memid_t memid, mi_stats_t* stats);
+void       _mi_os_free_ex(void* p, size_t size, bool still_committed, mi_memid_t memid, mi_stats_t* stats);
+
+size_t     _mi_os_page_size(void);
+size_t     _mi_os_good_alloc_size(size_t size);
+bool       _mi_os_has_overcommit(void);
+bool       _mi_os_has_virtual_reserve(void);
+
+bool       _mi_os_purge(void* p, size_t size, mi_stats_t* stats);
+bool       _mi_os_reset(void* addr, size_t size, mi_stats_t* tld_stats);
+bool       _mi_os_commit(void* p, size_t size, bool* is_zero, mi_stats_t* stats);
+bool       _mi_os_decommit(void* addr, size_t size, mi_stats_t* stats);
+bool       _mi_os_protect(void* addr, size_t size);
+bool       _mi_os_unprotect(void* addr, size_t size);
+bool       _mi_os_purge(void* p, size_t size, mi_stats_t* stats);
+bool       _mi_os_purge_ex(void* p, size_t size, bool allow_reset, mi_stats_t* stats);
+
+void*      _mi_os_alloc_aligned(size_t size, size_t alignment, bool commit, bool allow_large, mi_memid_t* memid, mi_stats_t* stats);
+void*      _mi_os_alloc_aligned_at_offset(size_t size, size_t alignment, size_t align_offset, bool commit, bool allow_large, mi_memid_t* memid, mi_stats_t* tld_stats);
+
+void*      _mi_os_get_aligned_hint(size_t try_alignment, size_t size);
+bool       _mi_os_use_large_page(size_t size, size_t alignment);
+size_t     _mi_os_large_page_size(void);
+
+void*      _mi_os_alloc_huge_os_pages(size_t pages, int numa_node, mi_msecs_t max_secs, size_t* pages_reserved, size_t* psize, mi_memid_t* memid);
+
+// arena.c
+mi_arena_id_t _mi_arena_id_none(void);
+void       _mi_arena_free(void* p, size_t size, size_t still_committed_size, mi_memid_t memid, mi_stats_t* stats);
+void*      _mi_arena_alloc(size_t size, bool commit, bool allow_large, mi_arena_id_t req_arena_id, mi_memid_t* memid, mi_os_tld_t* tld);
+void*      _mi_arena_alloc_aligned(size_t size, size_t alignment, size_t align_offset, bool commit, bool allow_large, mi_arena_id_t req_arena_id, mi_memid_t* memid, mi_os_tld_t* tld);
+bool       _mi_arena_memid_is_suitable(mi_memid_t memid, mi_arena_id_t request_arena_id);
+bool       _mi_arena_contains(const void* p);
+void       _mi_arena_collect(bool force_purge, mi_stats_t* stats);
+void       _mi_arena_unsafe_destroy_all(mi_stats_t* stats);
+
+// "segment-map.c"
+void       _mi_segment_map_allocated_at(const mi_segment_t* segment);
+void       _mi_segment_map_freed_at(const mi_segment_t* segment);
+
+// "segment.c"
+mi_page_t* _mi_segment_page_alloc(mi_heap_t* heap, size_t block_size, size_t page_alignment, mi_segments_tld_t* tld, mi_os_tld_t* os_tld);
+void       _mi_segment_page_free(mi_page_t* page, bool force, mi_segments_tld_t* tld);
+void       _mi_segment_page_abandon(mi_page_t* page, mi_segments_tld_t* tld);
+bool       _mi_segment_try_reclaim_abandoned( mi_heap_t* heap, bool try_all, mi_segments_tld_t* tld);
+void       _mi_segment_thread_collect(mi_segments_tld_t* tld);
+
+#if MI_HUGE_PAGE_ABANDON
+void       _mi_segment_huge_page_free(mi_segment_t* segment, mi_page_t* page, mi_block_t* block);
+#else
+void       _mi_segment_huge_page_reset(mi_segment_t* segment, mi_page_t* page, mi_block_t* block);
+#endif
+
+uint8_t*   _mi_segment_page_start(const mi_segment_t* segment, const mi_page_t* page, size_t* page_size); // page start for any page
+void       _mi_abandoned_reclaim_all(mi_heap_t* heap, mi_segments_tld_t* tld);
+void       _mi_abandoned_await_readers(void);
+void       _mi_abandoned_collect(mi_heap_t* heap, bool force, mi_segments_tld_t* tld);
+
+// "page.c"
+void*      _mi_malloc_generic(mi_heap_t* heap, size_t size, bool zero, size_t huge_alignment)  mi_attr_noexcept mi_attr_malloc;
+
+void       _mi_page_retire(mi_page_t* page) mi_attr_noexcept;                  // free the page if there are no other pages with many free blocks
+void       _mi_page_unfull(mi_page_t* page);
+void       _mi_page_free(mi_page_t* page, mi_page_queue_t* pq, bool force);   // free the page
+void       _mi_page_abandon(mi_page_t* page, mi_page_queue_t* pq);            // abandon the page, to be picked up by another thread...
+void       _mi_heap_delayed_free_all(mi_heap_t* heap);
+bool       _mi_heap_delayed_free_partial(mi_heap_t* heap);
+void       _mi_heap_collect_retired(mi_heap_t* heap, bool force);
+
+void       _mi_page_use_delayed_free(mi_page_t* page, mi_delayed_t delay, bool override_never);
+bool       _mi_page_try_use_delayed_free(mi_page_t* page, mi_delayed_t delay, bool override_never);
+size_t     _mi_page_queue_append(mi_heap_t* heap, mi_page_queue_t* pq, mi_page_queue_t* append);
+void       _mi_deferred_free(mi_heap_t* heap, bool force);
+
+void       _mi_page_free_collect(mi_page_t* page,bool force);
+void       _mi_page_reclaim(mi_heap_t* heap, mi_page_t* page);   // callback from segments
+
+size_t     _mi_bin_size(uint8_t bin);           // for stats
+uint8_t    _mi_bin(size_t size);                // for stats
+
+// "heap.c"
+void       _mi_heap_destroy_pages(mi_heap_t* heap);
+void       _mi_heap_collect_abandon(mi_heap_t* heap);
+void       _mi_heap_set_default_direct(mi_heap_t* heap);
+bool       _mi_heap_memid_is_suitable(mi_heap_t* heap, mi_memid_t memid);
+void       _mi_heap_unsafe_destroy_all(void);
+
+// "stats.c"
+void       _mi_stats_done(mi_stats_t* stats);
+mi_msecs_t  _mi_clock_now(void);
+mi_msecs_t  _mi_clock_end(mi_msecs_t start);
+mi_msecs_t  _mi_clock_start(void);
+
+// "alloc.c"
+void*       _mi_page_malloc(mi_heap_t* heap, mi_page_t* page, size_t size, bool zero) mi_attr_noexcept;  // called from `_mi_malloc_generic`
+void*       _mi_heap_malloc_zero(mi_heap_t* heap, size_t size, bool zero) mi_attr_noexcept;
+void*       _mi_heap_malloc_zero_ex(mi_heap_t* heap, size_t size, bool zero, size_t huge_alignment) mi_attr_noexcept;     // called from `_mi_heap_malloc_aligned`
+void*       _mi_heap_realloc_zero(mi_heap_t* heap, void* p, size_t newsize, bool zero) mi_attr_noexcept;
+mi_block_t* _mi_page_ptr_unalign(const mi_segment_t* segment, const mi_page_t* page, const void* p);
+bool        _mi_free_delayed_block(mi_block_t* block);
+void        _mi_free_generic(const mi_segment_t* segment, mi_page_t* page, bool is_local, void* p) mi_attr_noexcept;  // for runtime integration
+void        _mi_padding_shrink(const mi_page_t* page, const mi_block_t* block, const size_t min_size);
+
+// option.c, c primitives
+char        _mi_toupper(char c);
+int         _mi_strnicmp(const char* s, const char* t, size_t n);
+void        _mi_strlcpy(char* dest, const char* src, size_t dest_size);
+void        _mi_strlcat(char* dest, const char* src, size_t dest_size);
+size_t      _mi_strlen(const char* s);
+size_t      _mi_strnlen(const char* s, size_t max_len);
+
+
+#if MI_DEBUG>1
+bool        _mi_page_is_valid(mi_page_t* page);
+#endif
+
+
+// ------------------------------------------------------
+// Branches
+// ------------------------------------------------------
+
+#if defined(__GNUC__) || defined(__clang__)
+#define mi_unlikely(x)     (__builtin_expect(!!(x),false))
+#define mi_likely(x)       (__builtin_expect(!!(x),true))
+#elif (defined(__cplusplus) && (__cplusplus >= 202002L)) || (defined(_MSVC_LANG) && _MSVC_LANG >= 202002L)
+#define mi_unlikely(x)     (x) [[unlikely]]
+#define mi_likely(x)       (x) [[likely]]
+#else
+#define mi_unlikely(x)     (x)
+#define mi_likely(x)       (x)
+#endif
+
+#ifndef __has_builtin
+#define __has_builtin(x)  0
+#endif
+
+
+/* -----------------------------------------------------------
+  Error codes passed to `_mi_fatal_error`
+  All are recoverable but EFAULT is a serious error and aborts by default in secure mode.
+  For portability define undefined error codes using common Unix codes:
+  <https://www-numi.fnal.gov/offline_software/srt_public_context/WebDocs/Errors/unix_system_errors.html>
+----------------------------------------------------------- */
+#include <errno.h>
+#ifndef EAGAIN         // double free
+#define EAGAIN (11)
+#endif
+#ifndef ENOMEM         // out of memory
+#define ENOMEM (12)
+#endif
+#ifndef EFAULT         // corrupted free-list or meta-data
+#define EFAULT (14)
+#endif
+#ifndef EINVAL         // trying to free an invalid pointer
+#define EINVAL (22)
+#endif
+#ifndef EOVERFLOW      // count*size overflow
+#define EOVERFLOW (75)
+#endif
+
+
+/* -----------------------------------------------------------
+  Inlined definitions
+----------------------------------------------------------- */
+#define MI_UNUSED(x)     (void)(x)
+#if (MI_DEBUG>0)
+#define MI_UNUSED_RELEASE(x)
+#else
+#define MI_UNUSED_RELEASE(x)  MI_UNUSED(x)
+#endif
+
+#define MI_INIT4(x)   x(),x(),x(),x()
+#define MI_INIT8(x)   MI_INIT4(x),MI_INIT4(x)
+#define MI_INIT16(x)  MI_INIT8(x),MI_INIT8(x)
+#define MI_INIT32(x)  MI_INIT16(x),MI_INIT16(x)
+#define MI_INIT64(x)  MI_INIT32(x),MI_INIT32(x)
+#define MI_INIT128(x) MI_INIT64(x),MI_INIT64(x)
+#define MI_INIT256(x) MI_INIT128(x),MI_INIT128(x)
+
+
+#include <string.h>
+// initialize a local variable to zero; use memset as compilers optimize constant sized memset's
+#define _mi_memzero_var(x)  memset(&x,0,sizeof(x))
+
+// Is `x` a power of two? (0 is considered a power of two)
+static inline bool _mi_is_power_of_two(uintptr_t x) {
+  return ((x & (x - 1)) == 0);
+}
+
+// Is a pointer aligned?
+static inline bool _mi_is_aligned(void* p, size_t alignment) {
+  mi_assert_internal(alignment != 0);
+  return (((uintptr_t)p % alignment) == 0);
+}
+
+// Align upwards
+static inline uintptr_t _mi_align_up(uintptr_t sz, size_t alignment) {
+  mi_assert_internal(alignment != 0);
+  uintptr_t mask = alignment - 1;
+  if ((alignment & mask) == 0) {  // power of two?
+    return ((sz + mask) & ~mask);
+  }
+  else {
+    return (((sz + mask)/alignment)*alignment);
+  }
+}
+
+// Align downwards
+static inline uintptr_t _mi_align_down(uintptr_t sz, size_t alignment) {
+  mi_assert_internal(alignment != 0);
+  uintptr_t mask = alignment - 1;
+  if ((alignment & mask) == 0) { // power of two?
+    return (sz & ~mask);
+  }
+  else {
+    return ((sz / alignment) * alignment);
+  }
+}
+
+// Divide upwards: `s <= _mi_divide_up(s,d)*d < s+d`.
+static inline uintptr_t _mi_divide_up(uintptr_t size, size_t divider) {
+  mi_assert_internal(divider != 0);
+  return (divider == 0 ? size : ((size + divider - 1) / divider));
+}
+
+// Is memory zero initialized?
+static inline bool mi_mem_is_zero(const void* p, size_t size) {
+  for (size_t i = 0; i < size; i++) {
+    if (((uint8_t*)p)[i] != 0) return false;
+  }
+  return true;
+}
+
+
+// Align a byte size to a size in _machine words_,
+// i.e. byte size == `wsize*sizeof(void*)`.
+static inline size_t _mi_wsize_from_size(size_t size) {
+  mi_assert_internal(size <= SIZE_MAX - sizeof(uintptr_t));
+  return (size + sizeof(uintptr_t) - 1) / sizeof(uintptr_t);
+}
+
+// Overflow detecting multiply
+#if __has_builtin(__builtin_umul_overflow) || (defined(__GNUC__) && (__GNUC__ >= 5))
+#include <limits.h>      // UINT_MAX, ULONG_MAX
+#if defined(_CLOCK_T)    // for Illumos
+#undef _CLOCK_T
+#endif
+static inline bool mi_mul_overflow(size_t count, size_t size, size_t* total) {
+  #if (SIZE_MAX == ULONG_MAX)
+    return __builtin_umull_overflow(count, size, (unsigned long *)total);
+  #elif (SIZE_MAX == UINT_MAX)
+    return __builtin_umul_overflow(count, size, (unsigned int *)total);
+  #else
+    return __builtin_umulll_overflow(count, size, (unsigned long long *)total);
+  #endif
+}
+#else /* __builtin_umul_overflow is unavailable */
+static inline bool mi_mul_overflow(size_t count, size_t size, size_t* total) {
+  #define MI_MUL_NO_OVERFLOW ((size_t)1 << (4*sizeof(size_t)))  // sqrt(SIZE_MAX)
+  *total = count * size;
+  // note: gcc/clang optimize this to directly check the overflow flag
+  return ((size >= MI_MUL_NO_OVERFLOW || count >= MI_MUL_NO_OVERFLOW) && size > 0 && (SIZE_MAX / size) < count);
+}
+#endif
+
+// Safe multiply `count*size` into `total`; return `true` on overflow.
+static inline bool mi_count_size_overflow(size_t count, size_t size, size_t* total) {
+  if (count==1) {  // quick check for the case where count is one (common for C++ allocators)
+    *total = size;
+    return false;
+  }
+  else if mi_unlikely(mi_mul_overflow(count, size, total)) {
+    #if MI_DEBUG > 0
+    _mi_error_message(EOVERFLOW, "allocation request is too large (%zu * %zu bytes)\n", count, size);
+    #endif
+    *total = SIZE_MAX;
+    return true;
+  }
+  else return false;
+}
+
+
+/*----------------------------------------------------------------------------------------
+  Heap functions
+------------------------------------------------------------------------------------------- */
+
+extern const mi_heap_t _mi_heap_empty;  // read-only empty heap, initial value of the thread local default heap
+
+static inline bool mi_heap_is_backing(const mi_heap_t* heap) {
+  return (heap->tld->heap_backing == heap);
+}
+
+static inline bool mi_heap_is_initialized(mi_heap_t* heap) {
+  mi_assert_internal(heap != NULL);
+  return (heap != &_mi_heap_empty);
+}
+
+static inline uintptr_t _mi_ptr_cookie(const void* p) {
+  extern mi_heap_t _mi_heap_main;
+  mi_assert_internal(_mi_heap_main.cookie != 0);
+  return ((uintptr_t)p ^ _mi_heap_main.cookie);
+}
+
+/* -----------------------------------------------------------
+  Pages
+----------------------------------------------------------- */
+
+static inline mi_page_t* _mi_heap_get_free_small_page(mi_heap_t* heap, size_t size) {
+  mi_assert_internal(size <= (MI_SMALL_SIZE_MAX + MI_PADDING_SIZE));
+  const size_t idx = _mi_wsize_from_size(size);
+  mi_assert_internal(idx < MI_PAGES_DIRECT);
+  return heap->pages_free_direct[idx];
+}
+
+// Segment that contains the pointer
+// Large aligned blocks may be aligned at N*MI_SEGMENT_SIZE (inside a huge segment > MI_SEGMENT_SIZE),
+// and we need align "down" to the segment info which is `MI_SEGMENT_SIZE` bytes before it;
+// therefore we align one byte before `p`.
+static inline mi_segment_t* _mi_ptr_segment(const void* p) {
+  mi_assert_internal(p != NULL);
+  return (mi_segment_t*)(((uintptr_t)p - 1) & ~MI_SEGMENT_MASK);
+}
+
+static inline mi_page_t* mi_slice_to_page(mi_slice_t* s) {
+  mi_assert_internal(s->slice_offset== 0 && s->slice_count > 0);
+  return (mi_page_t*)(s);
+}
+
+static inline mi_slice_t* mi_page_to_slice(mi_page_t* p) {
+  mi_assert_internal(p->slice_offset== 0 && p->slice_count > 0);
+  return (mi_slice_t*)(p);
+}
+
+// Segment belonging to a page
+static inline mi_segment_t* _mi_page_segment(const mi_page_t* page) {
+  mi_segment_t* segment = _mi_ptr_segment(page);
+  mi_assert_internal(segment == NULL || ((mi_slice_t*)page >= segment->slices && (mi_slice_t*)page < segment->slices + segment->slice_entries));
+  return segment;
+}
+
+static inline mi_slice_t* mi_slice_first(const mi_slice_t* slice) {
+  mi_slice_t* start = (mi_slice_t*)((uint8_t*)slice - slice->slice_offset);
+  mi_assert_internal(start >= _mi_ptr_segment(slice)->slices);
+  mi_assert_internal(start->slice_offset == 0);
+  mi_assert_internal(start + start->slice_count > slice);
+  return start;
+}
+
+// Get the page containing the pointer (performance critical as it is called in mi_free)
+static inline mi_page_t* _mi_segment_page_of(const mi_segment_t* segment, const void* p) {
+  mi_assert_internal(p > (void*)segment);
+  ptrdiff_t diff = (uint8_t*)p - (uint8_t*)segment;
+  mi_assert_internal(diff > 0 && diff <= (ptrdiff_t)MI_SEGMENT_SIZE);
+  size_t idx = (size_t)diff >> MI_SEGMENT_SLICE_SHIFT;
+  mi_assert_internal(idx <= segment->slice_entries);
+  mi_slice_t* slice0 = (mi_slice_t*)&segment->slices[idx];
+  mi_slice_t* slice = mi_slice_first(slice0);  // adjust to the block that holds the page data
+  mi_assert_internal(slice->slice_offset == 0);
+  mi_assert_internal(slice >= segment->slices && slice < segment->slices + segment->slice_entries);
+  return mi_slice_to_page(slice);
+}
+
+// Quick page start for initialized pages
+static inline uint8_t* _mi_page_start(const mi_segment_t* segment, const mi_page_t* page, size_t* page_size) {
+  return _mi_segment_page_start(segment, page, page_size);
+}
+
+// Get the page containing the pointer
+static inline mi_page_t* _mi_ptr_page(void* p) {
+  return _mi_segment_page_of(_mi_ptr_segment(p), p);
+}
+
+// Get the block size of a page (special case for huge objects)
+static inline size_t mi_page_block_size(const mi_page_t* page) {
+  const size_t bsize = page->xblock_size;
+  mi_assert_internal(bsize > 0);
+  if mi_likely(bsize < MI_HUGE_BLOCK_SIZE) {
+    return bsize;
+  }
+  else {
+    size_t psize;
+    _mi_segment_page_start(_mi_page_segment(page), page, &psize);
+    return psize;
+  }
+}
+
+static inline bool mi_page_is_huge(const mi_page_t* page) {
+  return (_mi_page_segment(page)->kind == MI_SEGMENT_HUGE);
+}
+
+// Get the usable block size of a page without fixed padding.
+// This may still include internal padding due to alignment and rounding up size classes.
+static inline size_t mi_page_usable_block_size(const mi_page_t* page) {
+  return mi_page_block_size(page) - MI_PADDING_SIZE;
+}
+
+// size of a segment
+static inline size_t mi_segment_size(mi_segment_t* segment) {
+  return segment->segment_slices * MI_SEGMENT_SLICE_SIZE;
+}
+
+static inline uint8_t* mi_segment_end(mi_segment_t* segment) {
+  return (uint8_t*)segment + mi_segment_size(segment);
+}
+
+// Thread free access
+static inline mi_block_t* mi_page_thread_free(const mi_page_t* page) {
+  return (mi_block_t*)(mi_atomic_load_relaxed(&((mi_page_t*)page)->xthread_free) & ~3);
+}
+
+static inline mi_delayed_t mi_page_thread_free_flag(const mi_page_t* page) {
+  return (mi_delayed_t)(mi_atomic_load_relaxed(&((mi_page_t*)page)->xthread_free) & 3);
+}
+
+// Heap access
+static inline mi_heap_t* mi_page_heap(const mi_page_t* page) {
+  return (mi_heap_t*)(mi_atomic_load_relaxed(&((mi_page_t*)page)->xheap));
+}
+
+static inline void mi_page_set_heap(mi_page_t* page, mi_heap_t* heap) {
+  mi_assert_internal(mi_page_thread_free_flag(page) != MI_DELAYED_FREEING);
+  mi_atomic_store_release(&page->xheap,(uintptr_t)heap);
+}
+
+// Thread free flag helpers
+static inline mi_block_t* mi_tf_block(mi_thread_free_t tf) {
+  return (mi_block_t*)(tf & ~0x03);
+}
+static inline mi_delayed_t mi_tf_delayed(mi_thread_free_t tf) {
+  return (mi_delayed_t)(tf & 0x03);
+}
+static inline mi_thread_free_t mi_tf_make(mi_block_t* block, mi_delayed_t delayed) {
+  return (mi_thread_free_t)((uintptr_t)block | (uintptr_t)delayed);
+}
+static inline mi_thread_free_t mi_tf_set_delayed(mi_thread_free_t tf, mi_delayed_t delayed) {
+  return mi_tf_make(mi_tf_block(tf),delayed);
+}
+static inline mi_thread_free_t mi_tf_set_block(mi_thread_free_t tf, mi_block_t* block) {
+  return mi_tf_make(block, mi_tf_delayed(tf));
+}
+
+// are all blocks in a page freed?
+// note: needs up-to-date used count, (as the `xthread_free` list may not be empty). see `_mi_page_collect_free`.
+static inline bool mi_page_all_free(const mi_page_t* page) {
+  mi_assert_internal(page != NULL);
+  return (page->used == 0);
+}
+
+// are there any available blocks?
+static inline bool mi_page_has_any_available(const mi_page_t* page) {
+  mi_assert_internal(page != NULL && page->reserved > 0);
+  return (page->used < page->reserved || (mi_page_thread_free(page) != NULL));
+}
+
+// are there immediately available blocks, i.e. blocks available on the free list.
+static inline bool mi_page_immediate_available(const mi_page_t* page) {
+  mi_assert_internal(page != NULL);
+  return (page->free != NULL);
+}
+
+// is more than 7/8th of a page in use?
+static inline bool mi_page_mostly_used(const mi_page_t* page) {
+  if (page==NULL) return true;
+  uint16_t frac = page->reserved / 8U;
+  return (page->reserved - page->used <= frac);
+}
+
+static inline mi_page_queue_t* mi_page_queue(const mi_heap_t* heap, size_t size) {
+  return &((mi_heap_t*)heap)->pages[_mi_bin(size)];
+}
+
+
+
+//-----------------------------------------------------------
+// Page flags
+//-----------------------------------------------------------
+static inline bool mi_page_is_in_full(const mi_page_t* page) {
+  return page->flags.x.in_full;
+}
+
+static inline void mi_page_set_in_full(mi_page_t* page, bool in_full) {
+  page->flags.x.in_full = in_full;
+}
+
+static inline bool mi_page_has_aligned(const mi_page_t* page) {
+  return page->flags.x.has_aligned;
+}
+
+static inline void mi_page_set_has_aligned(mi_page_t* page, bool has_aligned) {
+  page->flags.x.has_aligned = has_aligned;
+}
+
+
+/* -------------------------------------------------------------------
+Encoding/Decoding the free list next pointers
+
+This is to protect against buffer overflow exploits where the
+free list is mutated. Many hardened allocators xor the next pointer `p`
+with a secret key `k1`, as `p^k1`. This prevents overwriting with known
+values but might be still too weak: if the attacker can guess
+the pointer `p` this  can reveal `k1` (since `p^k1^p == k1`).
+Moreover, if multiple blocks can be read as well, the attacker can
+xor both as `(p1^k1) ^ (p2^k1) == p1^p2` which may reveal a lot
+about the pointers (and subsequently `k1`).
+
+Instead mimalloc uses an extra key `k2` and encodes as `((p^k2)<<<k1)+k1`.
+Since these operations are not associative, the above approaches do not
+work so well any more even if the `p` can be guesstimated. For example,
+for the read case we can subtract two entries to discard the `+k1` term,
+but that leads to `((p1^k2)<<<k1) - ((p2^k2)<<<k1)` at best.
+We include the left-rotation since xor and addition are otherwise linear
+in the lowest bit. Finally, both keys are unique per page which reduces
+the re-use of keys by a large factor.
+
+We also pass a separate `null` value to be used as `NULL` or otherwise
+`(k2<<<k1)+k1` would appear (too) often as a sentinel value.
+------------------------------------------------------------------- */
+
+static inline bool mi_is_in_same_segment(const void* p, const void* q) {
+  return (_mi_ptr_segment(p) == _mi_ptr_segment(q));
+}
+
+static inline bool mi_is_in_same_page(const void* p, const void* q) {
+  mi_segment_t* segment = _mi_ptr_segment(p);
+  if (_mi_ptr_segment(q) != segment) return false;
+  // assume q may be invalid // return (_mi_segment_page_of(segment, p) == _mi_segment_page_of(segment, q));
+  mi_page_t* page = _mi_segment_page_of(segment, p);
+  size_t psize;
+  uint8_t* start = _mi_segment_page_start(segment, page, &psize);
+  return (start <= (uint8_t*)q && (uint8_t*)q < start + psize);
+}
+
+static inline uintptr_t mi_rotl(uintptr_t x, uintptr_t shift) {
+  shift %= MI_INTPTR_BITS;
+  return (shift==0 ? x : ((x << shift) | (x >> (MI_INTPTR_BITS - shift))));
+}
+static inline uintptr_t mi_rotr(uintptr_t x, uintptr_t shift) {
+  shift %= MI_INTPTR_BITS;
+  return (shift==0 ? x : ((x >> shift) | (x << (MI_INTPTR_BITS - shift))));
+}
+
+static inline void* mi_ptr_decode(const void* null, const mi_encoded_t x, const uintptr_t* keys) {
+  void* p = (void*)(mi_rotr(x - keys[0], keys[0]) ^ keys[1]);
+  return (p==null ? NULL : p);
+}
+
+static inline mi_encoded_t mi_ptr_encode(const void* null, const void* p, const uintptr_t* keys) {
+  uintptr_t x = (uintptr_t)(p==NULL ? null : p);
+  return mi_rotl(x ^ keys[1], keys[0]) + keys[0];
+}
+
+static inline mi_block_t* mi_block_nextx( const void* null, const mi_block_t* block, const uintptr_t* keys ) {
+  mi_track_mem_defined(block,sizeof(mi_block_t));
+  mi_block_t* next;
+  #ifdef MI_ENCODE_FREELIST
+  next = (mi_block_t*)mi_ptr_decode(null, block->next, keys);
+  #else
+  MI_UNUSED(keys); MI_UNUSED(null);
+  next = (mi_block_t*)block->next;
+  #endif
+  mi_track_mem_noaccess(block,sizeof(mi_block_t));
+  return next;
+}
+
+static inline void mi_block_set_nextx(const void* null, mi_block_t* block, const mi_block_t* next, const uintptr_t* keys) {
+  mi_track_mem_undefined(block,sizeof(mi_block_t));
+  #ifdef MI_ENCODE_FREELIST
+  block->next = mi_ptr_encode(null, next, keys);
+  #else
+  MI_UNUSED(keys); MI_UNUSED(null);
+  block->next = (mi_encoded_t)next;
+  #endif
+  mi_track_mem_noaccess(block,sizeof(mi_block_t));
+}
+
+static inline mi_block_t* mi_block_next(const mi_page_t* page, const mi_block_t* block) {
+  #ifdef MI_ENCODE_FREELIST
+  mi_block_t* next = mi_block_nextx(page,block,page->keys);
+  // check for free list corruption: is `next` at least in the same page?
+  // TODO: check if `next` is `page->block_size` aligned?
+  if mi_unlikely(next!=NULL && !mi_is_in_same_page(block, next)) {
+    _mi_error_message(EFAULT, "corrupted free list entry of size %zub at %p: value 0x%zx\n", mi_page_block_size(page), block, (uintptr_t)next);
+    next = NULL;
+  }
+  return next;
+  #else
+  MI_UNUSED(page);
+  return mi_block_nextx(page,block,NULL);
+  #endif
+}
+
+static inline void mi_block_set_next(const mi_page_t* page, mi_block_t* block, const mi_block_t* next) {
+  #ifdef MI_ENCODE_FREELIST
+  mi_block_set_nextx(page,block,next, page->keys);
+  #else
+  MI_UNUSED(page);
+  mi_block_set_nextx(page,block,next,NULL);
+  #endif
+}
+
+
+// -------------------------------------------------------------------
+// commit mask
+// -------------------------------------------------------------------
+
+static inline void mi_commit_mask_create_empty(mi_commit_mask_t* cm) {
+  for (size_t i = 0; i < MI_COMMIT_MASK_FIELD_COUNT; i++) {
+    cm->mask[i] = 0;
+  }
+}
+
+static inline void mi_commit_mask_create_full(mi_commit_mask_t* cm) {
+  for (size_t i = 0; i < MI_COMMIT_MASK_FIELD_COUNT; i++) {
+    cm->mask[i] = ~((size_t)0);
+  }
+}
+
+static inline bool mi_commit_mask_is_empty(const mi_commit_mask_t* cm) {
+  for (size_t i = 0; i < MI_COMMIT_MASK_FIELD_COUNT; i++) {
+    if (cm->mask[i] != 0) return false;
+  }
+  return true;
+}
+
+static inline bool mi_commit_mask_is_full(const mi_commit_mask_t* cm) {
+  for (size_t i = 0; i < MI_COMMIT_MASK_FIELD_COUNT; i++) {
+    if (cm->mask[i] != ~((size_t)0)) return false;
+  }
+  return true;
+}
+
+// defined in `segment.c`:
+size_t _mi_commit_mask_committed_size(const mi_commit_mask_t* cm, size_t total);
+size_t _mi_commit_mask_next_run(const mi_commit_mask_t* cm, size_t* idx);
+
+#define mi_commit_mask_foreach(cm,idx,count) \
+  idx = 0; \
+  while ((count = _mi_commit_mask_next_run(cm,&idx)) > 0) {
+
+#define mi_commit_mask_foreach_end() \
+    idx += count; \
+  }
+
+
+
+/* -----------------------------------------------------------
+  memory id's
+----------------------------------------------------------- */
+
+static inline mi_memid_t _mi_memid_create(mi_memkind_t memkind) {
+  mi_memid_t memid;
+  _mi_memzero_var(memid);
+  memid.memkind = memkind;
+  return memid;
+}
+
+static inline mi_memid_t _mi_memid_none(void) {
+  return _mi_memid_create(MI_MEM_NONE);
+}
+
+static inline mi_memid_t _mi_memid_create_os(bool committed, bool is_zero, bool is_large) {
+  mi_memid_t memid = _mi_memid_create(MI_MEM_OS);
+  memid.initially_committed = committed;
+  memid.initially_zero = is_zero;
+  memid.is_pinned = is_large;
+  return memid;
+}
+
+
+// -------------------------------------------------------------------
+// Fast "random" shuffle
+// -------------------------------------------------------------------
+
+static inline uintptr_t _mi_random_shuffle(uintptr_t x) {
+  if (x==0) { x = 17; }   // ensure we don't get stuck in generating zeros
+#if (MI_INTPTR_SIZE==8)
+  // by Sebastiano Vigna, see: <http://xoshiro.di.unimi.it/splitmix64.c>
+  x ^= x >> 30;
+  x *= 0xbf58476d1ce4e5b9UL;
+  x ^= x >> 27;
+  x *= 0x94d049bb133111ebUL;
+  x ^= x >> 31;
+#elif (MI_INTPTR_SIZE==4)
+  // by Chris Wellons, see: <https://nullprogram.com/blog/2018/07/31/>
+  x ^= x >> 16;
+  x *= 0x7feb352dUL;
+  x ^= x >> 15;
+  x *= 0x846ca68bUL;
+  x ^= x >> 16;
+#endif
+  return x;
+}
+
+// -------------------------------------------------------------------
+// Optimize numa node access for the common case (= one node)
+// -------------------------------------------------------------------
+
+int    _mi_os_numa_node_get(mi_os_tld_t* tld);
+size_t _mi_os_numa_node_count_get(void);
+
+extern _Atomic(size_t) _mi_numa_node_count;
+static inline int _mi_os_numa_node(mi_os_tld_t* tld) {
+  if mi_likely(mi_atomic_load_relaxed(&_mi_numa_node_count) == 1) { return 0; }
+  else return _mi_os_numa_node_get(tld);
+}
+static inline size_t _mi_os_numa_node_count(void) {
+  const size_t count = mi_atomic_load_relaxed(&_mi_numa_node_count);
+  if mi_likely(count > 0) { return count; }
+  else return _mi_os_numa_node_count_get();
+}
+
+
+
+// -----------------------------------------------------------------------
+// Count bits: trailing or leading zeros (with MI_INTPTR_BITS on all zero)
+// -----------------------------------------------------------------------
+
+#if defined(__GNUC__)
+
+#include <limits.h>       // LONG_MAX
+#define MI_HAVE_FAST_BITSCAN
+static inline size_t mi_clz(uintptr_t x) {
+  if (x==0) return MI_INTPTR_BITS;
+#if (INTPTR_MAX == LONG_MAX)
+  return __builtin_clzl(x);
+#else
+  return __builtin_clzll(x);
+#endif
+}
+static inline size_t mi_ctz(uintptr_t x) {
+  if (x==0) return MI_INTPTR_BITS;
+#if (INTPTR_MAX == LONG_MAX)
+  return __builtin_ctzl(x);
+#else
+  return __builtin_ctzll(x);
+#endif
+}
+
+#elif defined(_MSC_VER)
+
+#include <limits.h>       // LONG_MAX
+#include <intrin.h>       // BitScanReverse64
+#define MI_HAVE_FAST_BITSCAN
+static inline size_t mi_clz(uintptr_t x) {
+  if (x==0) return MI_INTPTR_BITS;
+  unsigned long idx;
+#if (INTPTR_MAX == LONG_MAX)
+  _BitScanReverse(&idx, x);
+#else
+  _BitScanReverse64(&idx, x);
+#endif
+  return ((MI_INTPTR_BITS - 1) - idx);
+}
+static inline size_t mi_ctz(uintptr_t x) {
+  if (x==0) return MI_INTPTR_BITS;
+  unsigned long idx;
+#if (INTPTR_MAX == LONG_MAX)
+  _BitScanForward(&idx, x);
+#else
+  _BitScanForward64(&idx, x);
+#endif
+  return idx;
+}
+
+#else
+static inline size_t mi_ctz32(uint32_t x) {
+  // de Bruijn multiplication, see <http://supertech.csail.mit.edu/papers/debruijn.pdf>
+  static const unsigned char debruijn[32] = {
+    0, 1, 28, 2, 29, 14, 24, 3, 30, 22, 20, 15, 25, 17, 4, 8,
+    31, 27, 13, 23, 21, 19, 16, 7, 26, 12, 18, 6, 11, 5, 10, 9
+  };
+  if (x==0) return 32;
+  return debruijn[((x & -(int32_t)x) * 0x077CB531UL) >> 27];
+}
+static inline size_t mi_clz32(uint32_t x) {
+  // de Bruijn multiplication, see <http://supertech.csail.mit.edu/papers/debruijn.pdf>
+  static const uint8_t debruijn[32] = {
+    31, 22, 30, 21, 18, 10, 29, 2, 20, 17, 15, 13, 9, 6, 28, 1,
+    23, 19, 11, 3, 16, 14, 7, 24, 12, 4, 8, 25, 5, 26, 27, 0
+  };
+  if (x==0) return 32;
+  x |= x >> 1;
+  x |= x >> 2;
+  x |= x >> 4;
+  x |= x >> 8;
+  x |= x >> 16;
+  return debruijn[(uint32_t)(x * 0x07C4ACDDUL) >> 27];
+}
+
+static inline size_t mi_clz(uintptr_t x) {
+  if (x==0) return MI_INTPTR_BITS;
+#if (MI_INTPTR_BITS <= 32)
+  return mi_clz32((uint32_t)x);
+#else
+  size_t count = mi_clz32((uint32_t)(x >> 32));
+  if (count < 32) return count;
+  return (32 + mi_clz32((uint32_t)x));
+#endif
+}
+static inline size_t mi_ctz(uintptr_t x) {
+  if (x==0) return MI_INTPTR_BITS;
+#if (MI_INTPTR_BITS <= 32)
+  return mi_ctz32((uint32_t)x);
+#else
+  size_t count = mi_ctz32((uint32_t)x);
+  if (count < 32) return count;
+  return (32 + mi_ctz32((uint32_t)(x>>32)));
+#endif
+}
+
+#endif
+
+// "bit scan reverse": Return index of the highest bit (or MI_INTPTR_BITS if `x` is zero)
+static inline size_t mi_bsr(uintptr_t x) {
+  return (x==0 ? MI_INTPTR_BITS : MI_INTPTR_BITS - 1 - mi_clz(x));
+}
+
+
+// ---------------------------------------------------------------------------------
+// Provide our own `_mi_memcpy` for potential performance optimizations.
+//
+// For now, only on Windows with msvc/clang-cl we optimize to `rep movsb` if
+// we happen to run on x86/x64 cpu's that have "fast short rep movsb" (FSRM) support
+// (AMD Zen3+ (~2020) or Intel Ice Lake+ (~2017). See also issue #201 and pr #253.
+// ---------------------------------------------------------------------------------
+
+#if !MI_TRACK_ENABLED && defined(_WIN32) && (defined(_M_IX86) || defined(_M_X64))
+#include <intrin.h>
+extern bool _mi_cpu_has_fsrm;
+static inline void _mi_memcpy(void* dst, const void* src, size_t n) {
+  if (_mi_cpu_has_fsrm) {
+    __movsb((unsigned char*)dst, (const unsigned char*)src, n);
+  }
+  else {
+    memcpy(dst, src, n);
+  }
+}
+static inline void _mi_memzero(void* dst, size_t n) {
+  if (_mi_cpu_has_fsrm) {
+    __stosb((unsigned char*)dst, 0, n);
+  }
+  else {
+    memset(dst, 0, n);
+  }
+}
+#else
+static inline void _mi_memcpy(void* dst, const void* src, size_t n) {
+  memcpy(dst, src, n);
+}
+static inline void _mi_memzero(void* dst, size_t n) {
+  memset(dst, 0, n);
+}
+#endif
+
+// -------------------------------------------------------------------------------
+// The `_mi_memcpy_aligned` can be used if the pointers are machine-word aligned
+// This is used for example in `mi_realloc`.
+// -------------------------------------------------------------------------------
+
+#if (defined(__GNUC__) && (__GNUC__ >= 4)) || defined(__clang__)
+// On GCC/CLang we provide a hint that the pointers are word aligned.
+static inline void _mi_memcpy_aligned(void* dst, const void* src, size_t n) {
+  mi_assert_internal(((uintptr_t)dst % MI_INTPTR_SIZE == 0) && ((uintptr_t)src % MI_INTPTR_SIZE == 0));
+  void* adst = __builtin_assume_aligned(dst, MI_INTPTR_SIZE);
+  const void* asrc = __builtin_assume_aligned(src, MI_INTPTR_SIZE);
+  _mi_memcpy(adst, asrc, n);
+}
+
+static inline void _mi_memzero_aligned(void* dst, size_t n) {
+  mi_assert_internal((uintptr_t)dst % MI_INTPTR_SIZE == 0);
+  void* adst = __builtin_assume_aligned(dst, MI_INTPTR_SIZE);
+  _mi_memzero(adst, n);
+}
+#else
+// Default fallback on `_mi_memcpy`
+static inline void _mi_memcpy_aligned(void* dst, const void* src, size_t n) {
+  mi_assert_internal(((uintptr_t)dst % MI_INTPTR_SIZE == 0) && ((uintptr_t)src % MI_INTPTR_SIZE == 0));
+  _mi_memcpy(dst, src, n);
+}
+
+static inline void _mi_memzero_aligned(void* dst, size_t n) {
+  mi_assert_internal((uintptr_t)dst % MI_INTPTR_SIZE == 0);
+  _mi_memzero(dst, n);
+}
+#endif
+
+
+#endif
diff --git a/compat/mimalloc/mimalloc/prim.h b/compat/mimalloc/mimalloc/prim.h
new file mode 100644
index 00000000000000..1e55cb5f8802d7
--- /dev/null
+++ b/compat/mimalloc/mimalloc/prim.h
@@ -0,0 +1,323 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2023, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+#pragma once
+#ifndef MIMALLOC_PRIM_H
+#define MIMALLOC_PRIM_H
+
+
+// --------------------------------------------------------------------------
+// This file specifies the primitive portability API.
+// Each OS/host needs to implement these primitives, see `src/prim`
+// for implementations on Window, macOS, WASI, and Linux/Unix.
+//
+// note: on all primitive functions, we always have result parameters != NUL, and:
+//  addr != NULL and page aligned
+//  size > 0     and page aligned
+//  return value is an error code an int where 0 is success.
+// --------------------------------------------------------------------------
+
+// OS memory configuration
+typedef struct mi_os_mem_config_s {
+  size_t  page_size;            // 4KiB
+  size_t  large_page_size;      // 2MiB
+  size_t  alloc_granularity;    // smallest allocation size (on Windows 64KiB)
+  bool    has_overcommit;       // can we reserve more memory than can be actually committed?
+  bool    must_free_whole;      // must allocated blocks be freed as a whole (false for mmap, true for VirtualAlloc)
+  bool    has_virtual_reserve;  // supports virtual address space reservation? (if true we can reserve virtual address space without using commit or physical memory)
+} mi_os_mem_config_t;
+
+// Initialize
+void _mi_prim_mem_init( mi_os_mem_config_t* config );
+
+// Free OS memory
+int _mi_prim_free(void* addr, size_t size );
+
+// Allocate OS memory. Return NULL on error.
+// The `try_alignment` is just a hint and the returned pointer does not have to be aligned.
+// If `commit` is false, the virtual memory range only needs to be reserved (with no access)
+// which will later be committed explicitly using `_mi_prim_commit`.
+// `is_zero` is set to true if the memory was zero initialized (as on most OS's)
+// pre: !commit => !allow_large
+//      try_alignment >= _mi_os_page_size() and a power of 2
+int _mi_prim_alloc(size_t size, size_t try_alignment, bool commit, bool allow_large, bool* is_large, bool* is_zero, void** addr);
+
+// Commit memory. Returns error code or 0 on success.
+// For example, on Linux this would make the memory PROT_READ|PROT_WRITE.
+// `is_zero` is set to true if the memory was zero initialized (e.g. on Windows)
+int _mi_prim_commit(void* addr, size_t size, bool* is_zero);
+
+// Decommit memory. Returns error code or 0 on success. The `needs_recommit` result is true
+// if the memory would need to be re-committed. For example, on Windows this is always true,
+// but on Linux we could use MADV_DONTNEED to decommit which does not need a recommit.
+// pre: needs_recommit != NULL
+int _mi_prim_decommit(void* addr, size_t size, bool* needs_recommit);
+
+// Reset memory. The range keeps being accessible but the content might be reset.
+// Returns error code or 0 on success.
+int _mi_prim_reset(void* addr, size_t size);
+
+// Protect memory. Returns error code or 0 on success.
+int _mi_prim_protect(void* addr, size_t size, bool protect);
+
+// Allocate huge (1GiB) pages possibly associated with a NUMA node.
+// `is_zero` is set to true if the memory was zero initialized (as on most OS's)
+// pre: size > 0  and a multiple of 1GiB.
+//      numa_node is either negative (don't care), or a numa node number.
+int _mi_prim_alloc_huge_os_pages(void* hint_addr, size_t size, int numa_node, bool* is_zero, void** addr);
+
+// Return the current NUMA node
+size_t _mi_prim_numa_node(void);
+
+// Return the number of logical NUMA nodes
+size_t _mi_prim_numa_node_count(void);
+
+// Clock ticks
+mi_msecs_t _mi_prim_clock_now(void);
+
+// Return process information (only for statistics)
+typedef struct mi_process_info_s {
+  mi_msecs_t  elapsed;
+  mi_msecs_t  utime;
+  mi_msecs_t  stime;
+  size_t      current_rss;
+  size_t      peak_rss;
+  size_t      current_commit;
+  size_t      peak_commit;
+  size_t      page_faults;
+} mi_process_info_t;
+
+void _mi_prim_process_info(mi_process_info_t* pinfo);
+
+// Default stderr output. (only for warnings etc. with verbose enabled)
+// msg != NULL && _mi_strlen(msg) > 0
+void _mi_prim_out_stderr( const char* msg );
+
+// Get an environment variable. (only for options)
+// name != NULL, result != NULL, result_size >= 64
+bool _mi_prim_getenv(const char* name, char* result, size_t result_size);
+
+
+// Fill a buffer with strong randomness; return `false` on error or if
+// there is no strong randomization available.
+bool _mi_prim_random_buf(void* buf, size_t buf_len);
+
+// Called on the first thread start, and should ensure `_mi_thread_done` is called on thread termination.
+void _mi_prim_thread_init_auto_done(void);
+
+// Called on process exit and may take action to clean up resources associated with the thread auto done.
+void _mi_prim_thread_done_auto_done(void);
+
+// Called when the default heap for a thread changes
+void _mi_prim_thread_associate_default_heap(mi_heap_t* heap);
+
+
+//-------------------------------------------------------------------
+// Thread id: `_mi_prim_thread_id()`
+//
+// Getting the thread id should be performant as it is called in the
+// fast path of `_mi_free` and we specialize for various platforms as
+// inlined definitions. Regular code should call `init.c:_mi_thread_id()`.
+// We only require _mi_prim_thread_id() to return a unique id
+// for each thread (unequal to zero).
+//-------------------------------------------------------------------
+
+// defined in `init.c`; do not use these directly
+extern mi_decl_thread mi_heap_t* _mi_heap_default;  // default heap to allocate from
+extern bool _mi_process_is_initialized;             // has mi_process_init been called?
+
+static inline mi_threadid_t _mi_prim_thread_id(void) mi_attr_noexcept;
+
+#if defined(_WIN32)
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+static inline mi_threadid_t _mi_prim_thread_id(void) mi_attr_noexcept {
+  // Windows: works on Intel and ARM in both 32- and 64-bit
+  return (uintptr_t)NtCurrentTeb();
+}
+
+// We use assembly for a fast thread id on the main platforms. The TLS layout depends on
+// both the OS and libc implementation so we use specific tests for each main platform.
+// If you test on another platform and it works please send a PR :-)
+// see also https://akkadia.org/drepper/tls.pdf for more info on the TLS register.
+#elif defined(__GNUC__) && ( \
+	   (defined(__GLIBC__)   && (defined(__x86_64__) || defined(__i386__) || defined(__arm__) || defined(__aarch64__))) \
+	|| (defined(__APPLE__)   && (defined(__x86_64__) || defined(__aarch64__))) \
+	|| (defined(__BIONIC__)  && (defined(__x86_64__) || defined(__i386__) || defined(__arm__) || defined(__aarch64__))) \
+	|| (defined(__FreeBSD__) && (defined(__x86_64__) || defined(__i386__) || defined(__aarch64__))) \
+	|| (defined(__OpenBSD__) && (defined(__x86_64__) || defined(__i386__) || defined(__aarch64__))) \
+      )
+
+static inline void* mi_prim_tls_slot(size_t slot) mi_attr_noexcept {
+  void* res;
+  const size_t ofs = (slot*sizeof(void*));
+  #if defined(__i386__)
+    __asm__("movl %%gs:%1, %0" : "=r" (res) : "m" (*((void**)ofs)) : );  // x86 32-bit always uses GS
+  #elif defined(__APPLE__) && defined(__x86_64__)
+    __asm__("movq %%gs:%1, %0" : "=r" (res) : "m" (*((void**)ofs)) : );  // x86_64 macOSX uses GS
+  #elif defined(__x86_64__) && (MI_INTPTR_SIZE==4)
+    __asm__("movl %%fs:%1, %0" : "=r" (res) : "m" (*((void**)ofs)) : );  // x32 ABI
+  #elif defined(__x86_64__)
+    __asm__("movq %%fs:%1, %0" : "=r" (res) : "m" (*((void**)ofs)) : );  // x86_64 Linux, BSD uses FS
+  #elif defined(__arm__)
+    void** tcb; MI_UNUSED(ofs);
+    __asm__ volatile ("mrc p15, 0, %0, c13, c0, 3\nbic %0, %0, #3" : "=r" (tcb));
+    res = tcb[slot];
+  #elif defined(__aarch64__)
+    void** tcb; MI_UNUSED(ofs);
+    #if defined(__APPLE__) // M1, issue #343
+    __asm__ volatile ("mrs %0, tpidrro_el0\nbic %0, %0, #7" : "=r" (tcb));
+    #else
+    __asm__ volatile ("mrs %0, tpidr_el0" : "=r" (tcb));
+    #endif
+    res = tcb[slot];
+  #endif
+  return res;
+}
+
+// setting a tls slot is only used on macOS for now
+static inline void mi_prim_tls_slot_set(size_t slot, void* value) mi_attr_noexcept {
+  const size_t ofs = (slot*sizeof(void*));
+  #if defined(__i386__)
+    __asm__("movl %1,%%gs:%0" : "=m" (*((void**)ofs)) : "rn" (value) : );  // 32-bit always uses GS
+  #elif defined(__APPLE__) && defined(__x86_64__)
+    __asm__("movq %1,%%gs:%0" : "=m" (*((void**)ofs)) : "rn" (value) : );  // x86_64 macOS uses GS
+  #elif defined(__x86_64__) && (MI_INTPTR_SIZE==4)
+    __asm__("movl %1,%%fs:%0" : "=m" (*((void**)ofs)) : "rn" (value) : );  // x32 ABI
+  #elif defined(__x86_64__)
+    __asm__("movq %1,%%fs:%0" : "=m" (*((void**)ofs)) : "rn" (value) : );  // x86_64 Linux, BSD uses FS
+  #elif defined(__arm__)
+    void** tcb; MI_UNUSED(ofs);
+    __asm__ volatile ("mrc p15, 0, %0, c13, c0, 3\nbic %0, %0, #3" : "=r" (tcb));
+    tcb[slot] = value;
+  #elif defined(__aarch64__)
+    void** tcb; MI_UNUSED(ofs);
+    #if defined(__APPLE__) // M1, issue #343
+    __asm__ volatile ("mrs %0, tpidrro_el0\nbic %0, %0, #7" : "=r" (tcb));
+    #else
+    __asm__ volatile ("mrs %0, tpidr_el0" : "=r" (tcb));
+    #endif
+    tcb[slot] = value;
+  #endif
+}
+
+static inline mi_threadid_t _mi_prim_thread_id(void) mi_attr_noexcept {
+  #if defined(__BIONIC__)
+    // issue #384, #495: on the Bionic libc (Android), slot 1 is the thread id
+    // see: https://github.com/aosp-mirror/platform_bionic/blob/c44b1d0676ded732df4b3b21c5f798eacae93228/libc/platform/bionic/tls_defines.h#L86
+    return (uintptr_t)mi_prim_tls_slot(1);
+  #else
+    // in all our other targets, slot 0 is the thread id
+    // glibc: https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=sysdeps/x86_64/nptl/tls.h
+    // apple: https://github.com/apple/darwin-xnu/blob/main/libsyscall/os/tsd.h#L36
+    return (uintptr_t)mi_prim_tls_slot(0);
+  #endif
+}
+
+#else
+
+// otherwise use portable C, taking the address of a thread local variable (this is still very fast on most platforms).
+static inline mi_threadid_t _mi_prim_thread_id(void) mi_attr_noexcept {
+  return (uintptr_t)&_mi_heap_default;
+}
+
+#endif
+
+
+
+/* ----------------------------------------------------------------------------------------
+The thread local default heap: `_mi_prim_get_default_heap()`
+This is inlined here as it is on the fast path for allocation functions.
+
+On most platforms (Windows, Linux, FreeBSD, NetBSD, etc), this just returns a
+__thread local variable (`_mi_heap_default`). With the initial-exec TLS model this ensures
+that the storage will always be available (allocated on the thread stacks).
+
+On some platforms though we cannot use that when overriding `malloc` since the underlying
+TLS implementation (or the loader) will call itself `malloc` on a first access and recurse.
+We try to circumvent this in an efficient way:
+- macOSX : we use an unused TLS slot from the OS allocated slots (MI_TLS_SLOT). On OSX, the
+	   loader itself calls `malloc` even before the modules are initialized.
+- OpenBSD: we use an unused slot from the pthread block (MI_TLS_PTHREAD_SLOT_OFS).
+- DragonFly: defaults are working but seem slow compared to freeBSD (see PR #323)
+------------------------------------------------------------------------------------------- */
+
+static inline mi_heap_t* mi_prim_get_default_heap(void);
+
+#if defined(MI_MALLOC_OVERRIDE)
+#if defined(__APPLE__) // macOS
+  #define MI_TLS_SLOT               89  // seems unused?
+  // #define MI_TLS_RECURSE_GUARD 1
+  // other possible unused ones are 9, 29, __PTK_FRAMEWORK_JAVASCRIPTCORE_KEY4 (94), __PTK_FRAMEWORK_GC_KEY9 (112) and __PTK_FRAMEWORK_OLDGC_KEY9 (89)
+  // see <https://github.com/rweichler/substrate/blob/master/include/pthread_machdep.h>
+#elif defined(__OpenBSD__)
+  // use end bytes of a name; goes wrong if anyone uses names > 23 characters (ptrhread specifies 16)
+  // see <https://github.com/openbsd/src/blob/master/lib/libc/include/thread_private.h#L371>
+  #define MI_TLS_PTHREAD_SLOT_OFS   (6*sizeof(int) + 4*sizeof(void*) + 24)
+  // #elif defined(__DragonFly__)
+  // #warning "mimalloc is not working correctly on DragonFly yet."
+  // #define MI_TLS_PTHREAD_SLOT_OFS   (4 + 1*sizeof(void*))  // offset `uniqueid` (also used by gdb?) <https://github.com/DragonFlyBSD/DragonFlyBSD/blob/master/lib/libthread_xu/thread/thr_private.h#L458>
+#elif defined(__ANDROID__)
+  // See issue #381
+  #define MI_TLS_PTHREAD
+#endif
+#endif
+
+
+#if defined(MI_TLS_SLOT)
+
+static inline mi_heap_t* mi_prim_get_default_heap(void) {
+  mi_heap_t* heap = (mi_heap_t*)mi_prim_tls_slot(MI_TLS_SLOT);
+  if mi_unlikely(heap == NULL) {
+    #ifdef __GNUC__
+    __asm(""); // prevent conditional load of the address of _mi_heap_empty
+    #endif
+    heap = (mi_heap_t*)&_mi_heap_empty;
+  }
+  return heap;
+}
+
+#elif defined(MI_TLS_PTHREAD_SLOT_OFS)
+
+static inline mi_heap_t** mi_prim_tls_pthread_heap_slot(void) {
+  pthread_t self = pthread_self();
+  #if defined(__DragonFly__)
+  if (self==NULL) return NULL;
+  #endif
+  return (mi_heap_t**)((uint8_t*)self + MI_TLS_PTHREAD_SLOT_OFS);
+}
+
+static inline mi_heap_t* mi_prim_get_default_heap(void) {
+  mi_heap_t** pheap = mi_prim_tls_pthread_heap_slot();
+  if mi_unlikely(pheap == NULL) return _mi_heap_main_get();
+  mi_heap_t* heap = *pheap;
+  if mi_unlikely(heap == NULL) return (mi_heap_t*)&_mi_heap_empty;
+  return heap;
+}
+
+#elif defined(MI_TLS_PTHREAD)
+
+extern pthread_key_t _mi_heap_default_key;
+static inline mi_heap_t* mi_prim_get_default_heap(void) {
+  mi_heap_t* heap = (mi_unlikely(_mi_heap_default_key == (pthread_key_t)(-1)) ? _mi_heap_main_get() : (mi_heap_t*)pthread_getspecific(_mi_heap_default_key));
+  return (mi_unlikely(heap == NULL) ? (mi_heap_t*)&_mi_heap_empty : heap);
+}
+
+#else // default using a thread local variable; used on most platforms.
+
+static inline mi_heap_t* mi_prim_get_default_heap(void) {
+  #if defined(MI_TLS_RECURSE_GUARD)
+  if (mi_unlikely(!_mi_process_is_initialized)) return _mi_heap_main_get();
+  #endif
+  return _mi_heap_default;
+}
+
+#endif  // mi_prim_get_default_heap()
+
+
+
+#endif  // MIMALLOC_PRIM_H
diff --git a/compat/mimalloc/mimalloc/track.h b/compat/mimalloc/mimalloc/track.h
new file mode 100644
index 00000000000000..fa1a048d846a9c
--- /dev/null
+++ b/compat/mimalloc/mimalloc/track.h
@@ -0,0 +1,147 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2023, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+#pragma once
+#ifndef MIMALLOC_TRACK_H
+#define MIMALLOC_TRACK_H
+
+/* ------------------------------------------------------------------------------------------------------
+Track memory ranges with macros for tools like Valgrind address sanitizer, or other memory checkers.
+These can be defined for tracking allocation:
+
+  #define mi_track_malloc_size(p,reqsize,size,zero)
+  #define mi_track_free_size(p,_size)
+
+The macros are set up such that the size passed to `mi_track_free_size`
+always matches the size of `mi_track_malloc_size`. (currently, `size == mi_usable_size(p)`).
+The `reqsize` is what the user requested, and `size >= reqsize`.
+The `size` is either byte precise (and `size==reqsize`) if `MI_PADDING` is enabled,
+or otherwise it is the usable block size which may be larger than the original request.
+Use `_mi_block_size_of(void* p)` to get the full block size that was allocated (including padding etc).
+The `zero` parameter is `true` if the allocated block is zero initialized.
+
+Optional:
+
+  #define mi_track_align(p,alignedp,offset,size)
+  #define mi_track_resize(p,oldsize,newsize)
+  #define mi_track_init()
+
+The `mi_track_align` is called right after a `mi_track_malloc` for aligned pointers in a block.
+The corresponding `mi_track_free` still uses the block start pointer and original size (corresponding to the `mi_track_malloc`).
+The `mi_track_resize` is currently unused but could be called on reallocations within a block.
+`mi_track_init` is called at program start.
+
+The following macros are for tools like asan and valgrind to track whether memory is
+defined, undefined, or not accessible at all:
+
+  #define mi_track_mem_defined(p,size)
+  #define mi_track_mem_undefined(p,size)
+  #define mi_track_mem_noaccess(p,size)
+
+-------------------------------------------------------------------------------------------------------*/
+
+#if MI_TRACK_VALGRIND
+// valgrind tool
+
+#define MI_TRACK_ENABLED      1
+#define MI_TRACK_HEAP_DESTROY 1           // track free of individual blocks on heap_destroy
+#define MI_TRACK_TOOL         "valgrind"
+
+#include <valgrind/valgrind.h>
+#include <valgrind/memcheck.h>
+
+#define mi_track_malloc_size(p,reqsize,size,zero) VALGRIND_MALLOCLIKE_BLOCK(p,size,MI_PADDING_SIZE /*red zone*/,zero)
+#define mi_track_free_size(p,_size)               VALGRIND_FREELIKE_BLOCK(p,MI_PADDING_SIZE /*red zone*/)
+#define mi_track_resize(p,oldsize,newsize)        VALGRIND_RESIZEINPLACE_BLOCK(p,oldsize,newsize,MI_PADDING_SIZE /*red zone*/)
+#define mi_track_mem_defined(p,size)              VALGRIND_MAKE_MEM_DEFINED(p,size)
+#define mi_track_mem_undefined(p,size)            VALGRIND_MAKE_MEM_UNDEFINED(p,size)
+#define mi_track_mem_noaccess(p,size)             VALGRIND_MAKE_MEM_NOACCESS(p,size)
+
+#elif MI_TRACK_ASAN
+// address sanitizer
+
+#define MI_TRACK_ENABLED      1
+#define MI_TRACK_HEAP_DESTROY 0
+#define MI_TRACK_TOOL         "asan"
+
+#include <sanitizer/asan_interface.h>
+
+#define mi_track_malloc_size(p,reqsize,size,zero) ASAN_UNPOISON_MEMORY_REGION(p,size)
+#define mi_track_free_size(p,size)                ASAN_POISON_MEMORY_REGION(p,size)
+#define mi_track_mem_defined(p,size)              ASAN_UNPOISON_MEMORY_REGION(p,size)
+#define mi_track_mem_undefined(p,size)            ASAN_UNPOISON_MEMORY_REGION(p,size)
+#define mi_track_mem_noaccess(p,size)             ASAN_POISON_MEMORY_REGION(p,size)
+
+#elif MI_TRACK_ETW
+// windows event tracing
+
+#define MI_TRACK_ENABLED      1
+#define MI_TRACK_HEAP_DESTROY 1
+#define MI_TRACK_TOOL         "ETW"
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#include "../src/prim/windows/etw.h"
+
+#define mi_track_init()                           EventRegistermicrosoft_windows_mimalloc();
+#define mi_track_malloc_size(p,reqsize,size,zero) EventWriteETW_MI_ALLOC((UINT64)(p), size)
+#define mi_track_free_size(p,size)                EventWriteETW_MI_FREE((UINT64)(p), size)
+
+#else
+// no tracking
+
+#define MI_TRACK_ENABLED      0
+#define MI_TRACK_HEAP_DESTROY 0
+#define MI_TRACK_TOOL         "none"
+
+#define mi_track_malloc_size(p,reqsize,size,zero)
+#define mi_track_free_size(p,_size)
+
+#endif
+
+// -------------------
+// Utility definitions
+
+#ifndef mi_track_resize
+#define mi_track_resize(p,oldsize,newsize)      mi_track_free_size(p,oldsize); mi_track_malloc(p,newsize,false)
+#endif
+
+#ifndef mi_track_align
+#define mi_track_align(p,alignedp,offset,size)  mi_track_mem_noaccess(p,offset)
+#endif
+
+#ifndef mi_track_init
+#define mi_track_init()
+#endif
+
+#ifndef mi_track_mem_defined
+#define mi_track_mem_defined(p,size)
+#endif
+
+#ifndef mi_track_mem_undefined
+#define mi_track_mem_undefined(p,size)
+#endif
+
+#ifndef mi_track_mem_noaccess
+#define mi_track_mem_noaccess(p,size)
+#endif
+
+
+#if MI_PADDING
+#define mi_track_malloc(p,reqsize,zero) \
+  if ((p)!=NULL) { \
+    mi_assert_internal(mi_usable_size(p)==(reqsize)); \
+    mi_track_malloc_size(p,reqsize,reqsize,zero); \
+  }
+#else
+#define mi_track_malloc(p,reqsize,zero) \
+  if ((p)!=NULL) { \
+    mi_assert_internal(mi_usable_size(p)>=(reqsize)); \
+    mi_track_malloc_size(p,reqsize,mi_usable_size(p),zero); \
+  }
+#endif
+
+#endif
diff --git a/compat/mimalloc/mimalloc/types.h b/compat/mimalloc/mimalloc/types.h
new file mode 100644
index 00000000000000..7616f37e4b978f
--- /dev/null
+++ b/compat/mimalloc/mimalloc/types.h
@@ -0,0 +1,670 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2023, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+#pragma once
+#ifndef MIMALLOC_TYPES_H
+#define MIMALLOC_TYPES_H
+
+// --------------------------------------------------------------------------
+// This file contains the main type definitions for mimalloc:
+// mi_heap_t      : all data for a thread-local heap, contains
+//                  lists of all managed heap pages.
+// mi_segment_t   : a larger chunk of memory (32GiB) from where pages
+//                  are allocated.
+// mi_page_t      : a mimalloc page (usually 64KiB or 512KiB) from
+//                  where objects are allocated.
+// --------------------------------------------------------------------------
+
+
+#include <stddef.h>   // ptrdiff_t
+#include <stdint.h>   // uintptr_t, uint16_t, etc
+#include "mimalloc/atomic.h"  // _Atomic
+
+#ifdef _MSC_VER
+#pragma warning(disable:4214) // bitfield is not int
+#endif
+
+// Minimal alignment necessary. On most platforms 16 bytes are needed
+// due to SSE registers for example. This must be at least `sizeof(void*)`
+#ifndef MI_MAX_ALIGN_SIZE
+#define MI_MAX_ALIGN_SIZE  16   // sizeof(max_align_t)
+#endif
+
+// ------------------------------------------------------
+// Variants
+// ------------------------------------------------------
+
+// Define NDEBUG in the release version to disable assertions.
+// #define NDEBUG
+
+// Define MI_TRACK_<tool> to enable tracking support
+// #define MI_TRACK_VALGRIND 1
+// #define MI_TRACK_ASAN     1
+// #define MI_TRACK_ETW      1
+
+// Define MI_STAT as 1 to maintain statistics; set it to 2 to have detailed statistics (but costs some performance).
+// #define MI_STAT 1
+
+// Define MI_SECURE to enable security mitigations
+// #define MI_SECURE 1  // guard page around metadata
+// #define MI_SECURE 2  // guard page around each mimalloc page
+// #define MI_SECURE 3  // encode free lists (detect corrupted free list (buffer overflow), and invalid pointer free)
+// #define MI_SECURE 4  // checks for double free. (may be more expensive)
+
+#if !defined(MI_SECURE)
+#define MI_SECURE 0
+#endif
+
+// Define MI_DEBUG for debug mode
+// #define MI_DEBUG 1  // basic assertion checks and statistics, check double free, corrupted free list, and invalid pointer free.
+// #define MI_DEBUG 2  // + internal assertion checks
+// #define MI_DEBUG 3  // + extensive internal invariant checking (cmake -DMI_DEBUG_FULL=ON)
+#if !defined(MI_DEBUG)
+#if !defined(NDEBUG) || defined(_DEBUG)
+#define MI_DEBUG 2
+#else
+#define MI_DEBUG 0
+#endif
+#endif
+
+// Reserve extra padding at the end of each block to be more resilient against heap block overflows.
+// The padding can detect buffer overflow on free.
+#if !defined(MI_PADDING) && (MI_SECURE>=3 || MI_DEBUG>=1 || (MI_TRACK_VALGRIND || MI_TRACK_ASAN || MI_TRACK_ETW))
+#define MI_PADDING  1
+#endif
+
+// Check padding bytes; allows byte-precise buffer overflow detection
+#if !defined(MI_PADDING_CHECK) && MI_PADDING && (MI_SECURE>=3 || MI_DEBUG>=1)
+#define MI_PADDING_CHECK 1
+#endif
+
+
+// Encoded free lists allow detection of corrupted free lists
+// and can detect buffer overflows, modify after free, and double `free`s.
+#if (MI_SECURE>=3 || MI_DEBUG>=1)
+#define MI_ENCODE_FREELIST  1
+#endif
+
+
+// We used to abandon huge pages but to eagerly deallocate if freed from another thread,
+// but that makes it not possible to visit them during a heap walk or include them in a
+// `mi_heap_destroy`. We therefore instead reset/decommit the huge blocks if freed from
+// another thread so most memory is available until it gets properly freed by the owning thread.
+// #define MI_HUGE_PAGE_ABANDON 1
+
+
+// ------------------------------------------------------
+// Platform specific values
+// ------------------------------------------------------
+
+// ------------------------------------------------------
+// Size of a pointer.
+// We assume that `sizeof(void*)==sizeof(intptr_t)`
+// and it holds for all platforms we know of.
+//
+// However, the C standard only requires that:
+//  p == (void*)((intptr_t)p))
+// but we also need:
+//  i == (intptr_t)((void*)i)
+// or otherwise one might define an intptr_t type that is larger than a pointer...
+// ------------------------------------------------------
+
+#if INTPTR_MAX > INT64_MAX
+# define MI_INTPTR_SHIFT (4)  // assume 128-bit  (as on arm CHERI for example)
+#elif INTPTR_MAX == INT64_MAX
+# define MI_INTPTR_SHIFT (3)
+#elif INTPTR_MAX == INT32_MAX
+# define MI_INTPTR_SHIFT (2)
+#else
+#error platform pointers must be 32, 64, or 128 bits
+#endif
+
+#if SIZE_MAX == UINT64_MAX
+# define MI_SIZE_SHIFT (3)
+typedef int64_t  mi_ssize_t;
+#elif SIZE_MAX == UINT32_MAX
+# define MI_SIZE_SHIFT (2)
+typedef int32_t  mi_ssize_t;
+#else
+#error platform objects must be 32 or 64 bits
+#endif
+
+#if (SIZE_MAX/2) > LONG_MAX
+# define MI_ZU(x)  x##ULL
+# define MI_ZI(x)  x##LL
+#else
+# define MI_ZU(x)  x##UL
+# define MI_ZI(x)  x##L
+#endif
+
+#define MI_INTPTR_SIZE  (1<<MI_INTPTR_SHIFT)
+#define MI_INTPTR_BITS  (MI_INTPTR_SIZE*8)
+
+#define MI_SIZE_SIZE  (1<<MI_SIZE_SHIFT)
+#define MI_SIZE_BITS  (MI_SIZE_SIZE*8)
+
+#define MI_KiB     (MI_ZU(1024))
+#define MI_MiB     (MI_KiB*MI_KiB)
+#define MI_GiB     (MI_MiB*MI_KiB)
+
+
+// ------------------------------------------------------
+// Main internal data-structures
+// ------------------------------------------------------
+
+// Main tuning parameters for segment and page sizes
+// Sizes for 64-bit (usually divide by two for 32-bit)
+#define MI_SEGMENT_SLICE_SHIFT            (13 + MI_INTPTR_SHIFT)         // 64KiB  (32KiB on 32-bit)
+
+#if MI_INTPTR_SIZE > 4
+#define MI_SEGMENT_SHIFT                  ( 9 + MI_SEGMENT_SLICE_SHIFT)  // 32MiB
+#else
+#define MI_SEGMENT_SHIFT                  ( 7 + MI_SEGMENT_SLICE_SHIFT)  // 4MiB on 32-bit
+#endif
+
+#define MI_SMALL_PAGE_SHIFT               (MI_SEGMENT_SLICE_SHIFT)       // 64KiB
+#define MI_MEDIUM_PAGE_SHIFT              ( 3 + MI_SMALL_PAGE_SHIFT)     // 512KiB
+
+
+// Derived constants
+#define MI_SEGMENT_SIZE                   (MI_ZU(1)<<MI_SEGMENT_SHIFT)
+#define MI_SEGMENT_ALIGN                  MI_SEGMENT_SIZE
+#define MI_SEGMENT_MASK                   ((uintptr_t)(MI_SEGMENT_ALIGN - 1))
+#define MI_SEGMENT_SLICE_SIZE             (MI_ZU(1)<< MI_SEGMENT_SLICE_SHIFT)
+#define MI_SLICES_PER_SEGMENT             (MI_SEGMENT_SIZE / MI_SEGMENT_SLICE_SIZE) // 1024
+
+#define MI_SMALL_PAGE_SIZE                (MI_ZU(1)<<MI_SMALL_PAGE_SHIFT)
+#define MI_MEDIUM_PAGE_SIZE               (MI_ZU(1)<<MI_MEDIUM_PAGE_SHIFT)
+
+#define MI_SMALL_OBJ_SIZE_MAX             (MI_SMALL_PAGE_SIZE/4)   // 8KiB on 64-bit
+#define MI_MEDIUM_OBJ_SIZE_MAX            (MI_MEDIUM_PAGE_SIZE/4)  // 128KiB on 64-bit
+#define MI_MEDIUM_OBJ_WSIZE_MAX           (MI_MEDIUM_OBJ_SIZE_MAX/MI_INTPTR_SIZE)
+#define MI_LARGE_OBJ_SIZE_MAX             (MI_SEGMENT_SIZE/2)      // 32MiB on 64-bit
+#define MI_LARGE_OBJ_WSIZE_MAX            (MI_LARGE_OBJ_SIZE_MAX/MI_INTPTR_SIZE)
+
+// Maximum number of size classes. (spaced exponentially in 12.5% increments)
+#define MI_BIN_HUGE  (73U)
+
+#if (MI_MEDIUM_OBJ_WSIZE_MAX >= 655360)
+#error "mimalloc internal: define more bins"
+#endif
+
+// Maximum slice offset (15)
+#define MI_MAX_SLICE_OFFSET               ((MI_ALIGNMENT_MAX / MI_SEGMENT_SLICE_SIZE) - 1)
+
+// Used as a special value to encode block sizes in 32 bits.
+#define MI_HUGE_BLOCK_SIZE                ((uint32_t)(2*MI_GiB))
+
+// blocks up to this size are always allocated aligned
+#define MI_MAX_ALIGN_GUARANTEE            (8*MI_MAX_ALIGN_SIZE)
+
+// Alignments over MI_ALIGNMENT_MAX are allocated in dedicated huge page segments
+#define MI_ALIGNMENT_MAX                  (MI_SEGMENT_SIZE >> 1)
+
+
+// ------------------------------------------------------
+// Mimalloc pages contain allocated blocks
+// ------------------------------------------------------
+
+// The free lists use encoded next fields
+// (Only actually encodes when MI_ENCODED_FREELIST is defined.)
+typedef uintptr_t  mi_encoded_t;
+
+// thread id's
+typedef size_t     mi_threadid_t;
+
+// free lists contain blocks
+typedef struct mi_block_s {
+  mi_encoded_t next;
+} mi_block_t;
+
+
+// The delayed flags are used for efficient multi-threaded free-ing
+typedef enum mi_delayed_e {
+  MI_USE_DELAYED_FREE   = 0, // push on the owning heap thread delayed list
+  MI_DELAYED_FREEING    = 1, // temporary: another thread is accessing the owning heap
+  MI_NO_DELAYED_FREE    = 2, // optimize: push on page local thread free queue if another block is already in the heap thread delayed free list
+  MI_NEVER_DELAYED_FREE = 3  // sticky, only resets on page reclaim
+} mi_delayed_t;
+
+
+// The `in_full` and `has_aligned` page flags are put in a union to efficiently
+// test if both are false (`full_aligned == 0`) in the `mi_free` routine.
+#if !MI_TSAN
+typedef union mi_page_flags_s {
+  uint8_t full_aligned;
+  struct {
+    uint8_t in_full : 1;
+    uint8_t has_aligned : 1;
+  } x;
+} mi_page_flags_t;
+#else
+// under thread sanitizer, use a byte for each flag to suppress warning, issue #130
+typedef union mi_page_flags_s {
+  uint16_t full_aligned;
+  struct {
+    uint8_t in_full;
+    uint8_t has_aligned;
+  } x;
+} mi_page_flags_t;
+#endif
+
+// Thread free list.
+// We use the bottom 2 bits of the pointer for mi_delayed_t flags
+typedef uintptr_t mi_thread_free_t;
+
+// A page contains blocks of one specific size (`block_size`).
+// Each page has three list of free blocks:
+// `free` for blocks that can be allocated,
+// `local_free` for freed blocks that are not yet available to `mi_malloc`
+// `thread_free` for freed blocks by other threads
+// The `local_free` and `thread_free` lists are migrated to the `free` list
+// when it is exhausted. The separate `local_free` list is necessary to
+// implement a monotonic heartbeat. The `thread_free` list is needed for
+// avoiding atomic operations in the common case.
+//
+//
+// `used - |thread_free|` == actual blocks that are in use (alive)
+// `used - |thread_free| + |free| + |local_free| == capacity`
+//
+// We don't count `freed` (as |free|) but use `used` to reduce
+// the number of memory accesses in the `mi_page_all_free` function(s).
+//
+// Notes:
+// - Access is optimized for `mi_free` and `mi_page_alloc` (in `alloc.c`)
+// - Using `uint16_t` does not seem to slow things down
+// - The size is 8 words on 64-bit which helps the page index calculations
+//   (and 10 words on 32-bit, and encoded free lists add 2 words. Sizes 10
+//    and 12 are still good for address calculation)
+// - To limit the structure size, the `xblock_size` is 32-bits only; for
+//   blocks > MI_HUGE_BLOCK_SIZE the size is determined from the segment page size
+// - `thread_free` uses the bottom bits as a delayed-free flags to optimize
+//   concurrent frees where only the first concurrent free adds to the owning
+//   heap `thread_delayed_free` list (see `alloc.c:mi_free_block_mt`).
+//   The invariant is that no-delayed-free is only set if there is
+//   at least one block that will be added, or as already been added, to
+//   the owning heap `thread_delayed_free` list. This guarantees that pages
+//   will be freed correctly even if only other threads free blocks.
+typedef struct mi_page_s {
+  // "owned" by the segment
+  uint32_t              slice_count;       // slices in this page (0 if not a page)
+  uint32_t              slice_offset;      // distance from the actual page data slice (0 if a page)
+  uint8_t               is_committed : 1;  // `true` if the page virtual memory is committed
+  uint8_t               is_zero_init : 1;  // `true` if the page was initially zero initialized
+
+  // layout like this to optimize access in `mi_malloc` and `mi_free`
+  uint16_t              capacity;          // number of blocks committed, must be the first field, see `segment.c:page_clear`
+  uint16_t              reserved;          // number of blocks reserved in memory
+  mi_page_flags_t       flags;             // `in_full` and `has_aligned` flags (8 bits)
+  uint8_t               free_is_zero : 1;  // `true` if the blocks in the free list are zero initialized
+  uint8_t               retire_expire : 7; // expiration count for retired blocks
+
+  mi_block_t*           free;              // list of available free blocks (`malloc` allocates from this list)
+  uint32_t              used;              // number of blocks in use (including blocks in `local_free` and `thread_free`)
+  uint32_t              xblock_size;       // size available in each block (always `>0`)
+  mi_block_t*           local_free;        // list of deferred free blocks by this thread (migrates to `free`)
+
+  #if (MI_ENCODE_FREELIST || MI_PADDING)
+  uintptr_t             keys[2];           // two random keys to encode the free lists (see `_mi_block_next`) or padding canary
+  #endif
+
+  _Atomic(mi_thread_free_t) xthread_free;  // list of deferred free blocks freed by other threads
+  _Atomic(uintptr_t)        xheap;
+
+  struct mi_page_s*     next;              // next page owned by this thread with the same `block_size`
+  struct mi_page_s*     prev;              // previous page owned by this thread with the same `block_size`
+
+  // 64-bit 9 words, 32-bit 12 words, (+2 for secure)
+  #if MI_INTPTR_SIZE==8
+  uintptr_t padding[1];
+  #endif
+} mi_page_t;
+
+
+
+// ------------------------------------------------------
+// Mimalloc segments contain mimalloc pages
+// ------------------------------------------------------
+
+typedef enum mi_page_kind_e {
+  MI_PAGE_SMALL,    // small blocks go into 64KiB pages inside a segment
+  MI_PAGE_MEDIUM,   // medium blocks go into medium pages inside a segment
+  MI_PAGE_LARGE,    // larger blocks go into a page of just one block
+  MI_PAGE_HUGE,     // huge blocks (> 16 MiB) are put into a single page in a single segment.
+} mi_page_kind_t;
+
+typedef enum mi_segment_kind_e {
+  MI_SEGMENT_NORMAL, // MI_SEGMENT_SIZE size with pages inside.
+  MI_SEGMENT_HUGE,   // > MI_LARGE_SIZE_MAX segment with just one huge page inside.
+} mi_segment_kind_t;
+
+// ------------------------------------------------------
+// A segment holds a commit mask where a bit is set if
+// the corresponding MI_COMMIT_SIZE area is committed.
+// The MI_COMMIT_SIZE must be a multiple of the slice
+// size. If it is equal we have the most fine grained
+// decommit (but setting it higher can be more efficient).
+// The MI_MINIMAL_COMMIT_SIZE is the minimal amount that will
+// be committed in one go which can be set higher than
+// MI_COMMIT_SIZE for efficiency (while the decommit mask
+// is still tracked in fine-grained MI_COMMIT_SIZE chunks)
+// ------------------------------------------------------
+
+#define MI_MINIMAL_COMMIT_SIZE      (1*MI_SEGMENT_SLICE_SIZE)
+#define MI_COMMIT_SIZE              (MI_SEGMENT_SLICE_SIZE)              // 64KiB
+#define MI_COMMIT_MASK_BITS         (MI_SEGMENT_SIZE / MI_COMMIT_SIZE)
+#define MI_COMMIT_MASK_FIELD_BITS    MI_SIZE_BITS
+#define MI_COMMIT_MASK_FIELD_COUNT  (MI_COMMIT_MASK_BITS / MI_COMMIT_MASK_FIELD_BITS)
+
+#if (MI_COMMIT_MASK_BITS != (MI_COMMIT_MASK_FIELD_COUNT * MI_COMMIT_MASK_FIELD_BITS))
+#error "the segment size must be exactly divisible by the (commit size * size_t bits)"
+#endif
+
+typedef struct mi_commit_mask_s {
+  size_t mask[MI_COMMIT_MASK_FIELD_COUNT];
+} mi_commit_mask_t;
+
+typedef mi_page_t  mi_slice_t;
+typedef int64_t    mi_msecs_t;
+
+
+// Memory can reside in arena's, direct OS allocated, or statically allocated. The memid keeps track of this.
+typedef enum mi_memkind_e {
+  MI_MEM_NONE,      // not allocated
+  MI_MEM_EXTERNAL,  // not owned by mimalloc but provided externally (via `mi_manage_os_memory` for example)
+  MI_MEM_STATIC,    // allocated in a static area and should not be freed (for arena meta data for example)
+  MI_MEM_OS,        // allocated from the OS
+  MI_MEM_OS_HUGE,   // allocated as huge os pages
+  MI_MEM_OS_REMAP,  // allocated in a remapable area (i.e. using `mremap`)
+  MI_MEM_ARENA      // allocated from an arena (the usual case)
+} mi_memkind_t;
+
+static inline bool mi_memkind_is_os(mi_memkind_t memkind) {
+  return (memkind >= MI_MEM_OS && memkind <= MI_MEM_OS_REMAP);
+}
+
+typedef struct mi_memid_os_info {
+  void*         base;               // actual base address of the block (used for offset aligned allocations)
+  size_t        alignment;          // alignment at allocation
+} mi_memid_os_info_t;
+
+typedef struct mi_memid_arena_info {
+  size_t        block_index;        // index in the arena
+  mi_arena_id_t id;                 // arena id (>= 1)
+  bool          is_exclusive;       // the arena can only be used for specific arena allocations
+} mi_memid_arena_info_t;
+
+typedef struct mi_memid_s {
+  union {
+    mi_memid_os_info_t    os;       // only used for MI_MEM_OS
+    mi_memid_arena_info_t arena;    // only used for MI_MEM_ARENA
+  } mem;
+  bool          is_pinned;          // `true` if we cannot decommit/reset/protect in this memory (e.g. when allocated using large OS pages)
+  bool          initially_committed;// `true` if the memory was originally allocated as committed
+  bool          initially_zero;     // `true` if the memory was originally zero initialized
+  mi_memkind_t  memkind;
+} mi_memid_t;
+
+
+// Segments are large allocated memory blocks (8mb on 64 bit) from
+// the OS. Inside segments we allocated fixed size _pages_ that
+// contain blocks.
+typedef struct mi_segment_s {
+  // constant fields
+  mi_memid_t        memid;              // memory id for arena allocation
+  bool              allow_decommit;
+  bool              allow_purge;
+  size_t            segment_size;
+
+  // segment fields
+  mi_msecs_t        purge_expire;
+  mi_commit_mask_t  purge_mask;
+  mi_commit_mask_t  commit_mask;
+
+  _Atomic(struct mi_segment_s*) abandoned_next;
+
+  // from here is zero initialized
+  struct mi_segment_s* next;            // the list of freed segments in the cache (must be first field, see `segment.c:mi_segment_init`)
+
+  size_t            abandoned;          // abandoned pages (i.e. the original owning thread stopped) (`abandoned <= used`)
+  size_t            abandoned_visits;   // count how often this segment is visited in the abandoned list (to force reclaim it it is too long)
+  size_t            used;               // count of pages in use
+  uintptr_t         cookie;             // verify addresses in debug mode: `mi_ptr_cookie(segment) == segment->cookie`
+
+  size_t            segment_slices;      // for huge segments this may be different from `MI_SLICES_PER_SEGMENT`
+  size_t            segment_info_slices; // initial slices we are using segment info and possible guard pages.
+
+  // layout like this to optimize access in `mi_free`
+  mi_segment_kind_t kind;
+  size_t            slice_entries;       // entries in the `slices` array, at most `MI_SLICES_PER_SEGMENT`
+  _Atomic(mi_threadid_t) thread_id;      // unique id of the thread owning this segment
+
+  mi_slice_t        slices[MI_SLICES_PER_SEGMENT+1];  // one more for huge blocks with large alignment
+} mi_segment_t;
+
+
+// ------------------------------------------------------
+// Heaps
+// Provide first-class heaps to allocate from.
+// A heap just owns a set of pages for allocation and
+// can only be allocate/reallocate from the thread that created it.
+// Freeing blocks can be done from any thread though.
+// Per thread, the segments are shared among its heaps.
+// Per thread, there is always a default heap that is
+// used for allocation; it is initialized to statically
+// point to an empty heap to avoid initialization checks
+// in the fast path.
+// ------------------------------------------------------
+
+// Thread local data
+typedef struct mi_tld_s mi_tld_t;
+
+// Pages of a certain block size are held in a queue.
+typedef struct mi_page_queue_s {
+  mi_page_t* first;
+  mi_page_t* last;
+  size_t     block_size;
+} mi_page_queue_t;
+
+#define MI_BIN_FULL  (MI_BIN_HUGE+1)
+
+// Random context
+typedef struct mi_random_cxt_s {
+  uint32_t input[16];
+  uint32_t output[16];
+  int      output_available;
+  bool     weak;
+} mi_random_ctx_t;
+
+
+// In debug mode there is a padding structure at the end of the blocks to check for buffer overflows
+#if (MI_PADDING)
+typedef struct mi_padding_s {
+  uint32_t canary; // encoded block value to check validity of the padding (in case of overflow)
+  uint32_t delta;  // padding bytes before the block. (mi_usable_size(p) - delta == exact allocated bytes)
+} mi_padding_t;
+#define MI_PADDING_SIZE   (sizeof(mi_padding_t))
+#define MI_PADDING_WSIZE  ((MI_PADDING_SIZE + MI_INTPTR_SIZE - 1) / MI_INTPTR_SIZE)
+#else
+#define MI_PADDING_SIZE   0
+#define MI_PADDING_WSIZE  0
+#endif
+
+#define MI_PAGES_DIRECT   (MI_SMALL_WSIZE_MAX + MI_PADDING_WSIZE + 1)
+
+
+// A heap owns a set of pages.
+struct mi_heap_s {
+  mi_tld_t*             tld;
+  mi_page_t*            pages_free_direct[MI_PAGES_DIRECT];  // optimize: array where every entry points a page with possibly free blocks in the corresponding queue for that size.
+  mi_page_queue_t       pages[MI_BIN_FULL + 1];              // queue of pages for each size class (or "bin")
+  _Atomic(mi_block_t*)  thread_delayed_free;
+  mi_threadid_t         thread_id;                           // thread this heap belongs too
+  mi_arena_id_t         arena_id;                            // arena id if the heap belongs to a specific arena (or 0)
+  uintptr_t             cookie;                              // random cookie to verify pointers (see `_mi_ptr_cookie`)
+  uintptr_t             keys[2];                             // two random keys used to encode the `thread_delayed_free` list
+  mi_random_ctx_t       random;                              // random number context used for secure allocation
+  size_t                page_count;                          // total number of pages in the `pages` queues.
+  size_t                page_retired_min;                    // smallest retired index (retired pages are fully free, but still in the page queues)
+  size_t                page_retired_max;                    // largest retired index into the `pages` array.
+  mi_heap_t*            next;                                // list of heaps per thread
+  bool                  no_reclaim;                          // `true` if this heap should not reclaim abandoned pages
+};
+
+
+
+// ------------------------------------------------------
+// Debug
+// ------------------------------------------------------
+
+#if !defined(MI_DEBUG_UNINIT)
+#define MI_DEBUG_UNINIT     (0xD0)
+#endif
+#if !defined(MI_DEBUG_FREED)
+#define MI_DEBUG_FREED      (0xDF)
+#endif
+#if !defined(MI_DEBUG_PADDING)
+#define MI_DEBUG_PADDING    (0xDE)
+#endif
+
+#if (MI_DEBUG)
+// use our own assertion to print without memory allocation
+void _mi_assert_fail(const char* assertion, const char* fname, unsigned int line, const char* func );
+#define mi_assert(expr)     ((expr) ? (void)0 : _mi_assert_fail(#expr,__FILE__,__LINE__,__func__))
+#else
+#define mi_assert(x)
+#endif
+
+#if (MI_DEBUG>1)
+#define mi_assert_internal    mi_assert
+#else
+#define mi_assert_internal(x)
+#endif
+
+#if (MI_DEBUG>2)
+#define mi_assert_expensive   mi_assert
+#else
+#define mi_assert_expensive(x)
+#endif
+
+// ------------------------------------------------------
+// Statistics
+// ------------------------------------------------------
+
+#ifndef MI_STAT
+#if (MI_DEBUG>0)
+#define MI_STAT 2
+#else
+#define MI_STAT 0
+#endif
+#endif
+
+typedef struct mi_stat_count_s {
+  int64_t allocated;
+  int64_t freed;
+  int64_t peak;
+  int64_t current;
+} mi_stat_count_t;
+
+typedef struct mi_stat_counter_s {
+  int64_t total;
+  int64_t count;
+} mi_stat_counter_t;
+
+typedef struct mi_stats_s {
+  mi_stat_count_t segments;
+  mi_stat_count_t pages;
+  mi_stat_count_t reserved;
+  mi_stat_count_t committed;
+  mi_stat_count_t reset;
+  mi_stat_count_t purged;
+  mi_stat_count_t page_committed;
+  mi_stat_count_t segments_abandoned;
+  mi_stat_count_t pages_abandoned;
+  mi_stat_count_t threads;
+  mi_stat_count_t normal;
+  mi_stat_count_t huge;
+  mi_stat_count_t large;
+  mi_stat_count_t malloc;
+  mi_stat_count_t segments_cache;
+  mi_stat_counter_t pages_extended;
+  mi_stat_counter_t mmap_calls;
+  mi_stat_counter_t commit_calls;
+  mi_stat_counter_t reset_calls;
+  mi_stat_counter_t purge_calls;
+  mi_stat_counter_t page_no_retire;
+  mi_stat_counter_t searches;
+  mi_stat_counter_t normal_count;
+  mi_stat_counter_t huge_count;
+  mi_stat_counter_t large_count;
+#if MI_STAT>1
+  mi_stat_count_t normal_bins[MI_BIN_HUGE+1];
+#endif
+} mi_stats_t;
+
+
+void _mi_stat_increase(mi_stat_count_t* stat, size_t amount);
+void _mi_stat_decrease(mi_stat_count_t* stat, size_t amount);
+void _mi_stat_counter_increase(mi_stat_counter_t* stat, size_t amount);
+
+#if (MI_STAT)
+#define mi_stat_increase(stat,amount)         _mi_stat_increase( &(stat), amount)
+#define mi_stat_decrease(stat,amount)         _mi_stat_decrease( &(stat), amount)
+#define mi_stat_counter_increase(stat,amount) _mi_stat_counter_increase( &(stat), amount)
+#else
+#define mi_stat_increase(stat,amount)         (void)0
+#define mi_stat_decrease(stat,amount)         (void)0
+#define mi_stat_counter_increase(stat,amount) (void)0
+#endif
+
+#define mi_heap_stat_counter_increase(heap,stat,amount)  mi_stat_counter_increase( (heap)->tld->stats.stat, amount)
+#define mi_heap_stat_increase(heap,stat,amount)  mi_stat_increase( (heap)->tld->stats.stat, amount)
+#define mi_heap_stat_decrease(heap,stat,amount)  mi_stat_decrease( (heap)->tld->stats.stat, amount)
+
+// ------------------------------------------------------
+// Thread Local data
+// ------------------------------------------------------
+
+// A "span" is is an available range of slices. The span queues keep
+// track of slice spans of at most the given `slice_count` (but more than the previous size class).
+typedef struct mi_span_queue_s {
+  mi_slice_t* first;
+  mi_slice_t* last;
+  size_t      slice_count;
+} mi_span_queue_t;
+
+#define MI_SEGMENT_BIN_MAX (35)     // 35 == mi_segment_bin(MI_SLICES_PER_SEGMENT)
+
+// OS thread local data
+typedef struct mi_os_tld_s {
+  size_t                region_idx;   // start point for next allocation
+  mi_stats_t*           stats;        // points to tld stats
+} mi_os_tld_t;
+
+
+// Segments thread local data
+typedef struct mi_segments_tld_s {
+  mi_span_queue_t     spans[MI_SEGMENT_BIN_MAX+1];  // free slice spans inside segments
+  size_t              count;        // current number of segments;
+  size_t              peak_count;   // peak number of segments
+  size_t              current_size; // current size of all segments
+  size_t              peak_size;    // peak size of all segments
+  mi_stats_t*         stats;        // points to tld stats
+  mi_os_tld_t*        os;           // points to os stats
+} mi_segments_tld_t;
+
+// Thread local data
+struct mi_tld_s {
+  unsigned long long  heartbeat;     // monotonic heartbeat count
+  bool                recurse;       // true if deferred was called; used to prevent infinite recursion.
+  mi_heap_t*          heap_backing;  // backing heap of this thread (cannot be deleted)
+  mi_heap_t*          heaps;         // list of heaps in this thread (so we can abandon all when the thread terminates)
+  mi_segments_tld_t   segments;      // segment tld
+  mi_os_tld_t         os;            // os tld
+  mi_stats_t          stats;         // statistics
+};
+
+#endif
diff --git a/compat/mimalloc/options.c b/compat/mimalloc/options.c
new file mode 100644
index 00000000000000..3a3090d9acfc94
--- /dev/null
+++ b/compat/mimalloc/options.c
@@ -0,0 +1,571 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2021, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "mimalloc/atomic.h"
+#include "mimalloc/prim.h"  // mi_prim_out_stderr
+
+#include <stdio.h>      // FILE
+#include <stdlib.h>     // abort
+#include <stdarg.h>
+
+
+static long mi_max_error_count   = 16; // stop outputting errors after this (use < 0 for no limit)
+static long mi_max_warning_count = 16; // stop outputting warnings after this (use < 0 for no limit)
+
+static void mi_add_stderr_output(void);
+
+int mi_version(void) mi_attr_noexcept {
+  return MI_MALLOC_VERSION;
+}
+
+
+// --------------------------------------------------------
+// Options
+// These can be accessed by multiple threads and may be
+// concurrently initialized, but an initializing data race
+// is ok since they resolve to the same value.
+// --------------------------------------------------------
+typedef enum mi_init_e {
+  UNINIT,       // not yet initialized
+  DEFAULTED,    // not found in the environment, use default value
+  INITIALIZED   // found in environment or set explicitly
+} mi_init_t;
+
+typedef struct mi_option_desc_s {
+  long        value;  // the value
+  mi_init_t   init;   // is it initialized yet? (from the environment)
+  mi_option_t option; // for debugging: the option index should match the option
+  const char* name;   // option name without `mimalloc_` prefix
+  const char* legacy_name; // potential legacy option name
+} mi_option_desc_t;
+
+#define MI_OPTION(opt)                  mi_option_##opt, #opt, NULL
+#define MI_OPTION_LEGACY(opt,legacy)    mi_option_##opt, #opt, #legacy
+
+static mi_option_desc_t options[_mi_option_last] =
+{
+  // stable options
+  #if MI_DEBUG || defined(MI_SHOW_ERRORS)
+  { 1, UNINIT, MI_OPTION(show_errors) },
+  #else
+  { 0, UNINIT, MI_OPTION(show_errors) },
+  #endif
+  { 0, UNINIT, MI_OPTION(show_stats) },
+  { 0, UNINIT, MI_OPTION(verbose) },
+
+  // the following options are experimental and not all combinations make sense.
+  { 1, UNINIT, MI_OPTION(eager_commit) },               // commit per segment directly (4MiB)  (but see also `eager_commit_delay`)
+  { 2, UNINIT, MI_OPTION_LEGACY(arena_eager_commit,eager_region_commit) }, // eager commit arena's? 2 is used to enable this only on an OS that has overcommit (i.e. linux)
+  { 1, UNINIT, MI_OPTION_LEGACY(purge_decommits,reset_decommits) },        // purge decommits memory (instead of reset) (note: on linux this uses MADV_DONTNEED for decommit)
+  { 0, UNINIT, MI_OPTION_LEGACY(allow_large_os_pages,large_os_pages) },    // use large OS pages, use only with eager commit to prevent fragmentation of VMA's
+  { 0, UNINIT, MI_OPTION(reserve_huge_os_pages) },      // per 1GiB huge pages
+  {-1, UNINIT, MI_OPTION(reserve_huge_os_pages_at) },   // reserve huge pages at node N
+  { 0, UNINIT, MI_OPTION(reserve_os_memory)     },
+  { 0, UNINIT, MI_OPTION(deprecated_segment_cache) },   // cache N segments per thread
+  { 0, UNINIT, MI_OPTION(deprecated_page_reset) },      // reset page memory on free
+  { 0, UNINIT, MI_OPTION_LEGACY(abandoned_page_purge,abandoned_page_reset) },       // reset free page memory when a thread terminates
+  { 0, UNINIT, MI_OPTION(deprecated_segment_reset) },   // reset segment memory on free (needs eager commit)
+#if defined(__NetBSD__)
+  { 0, UNINIT, MI_OPTION(eager_commit_delay) },         // the first N segments per thread are not eagerly committed
+#else
+  { 1, UNINIT, MI_OPTION(eager_commit_delay) },         // the first N segments per thread are not eagerly committed (but per page in the segment on demand)
+#endif
+  { 10,  UNINIT, MI_OPTION_LEGACY(purge_delay,reset_delay) },  // purge delay in milli-seconds
+  { 0,   UNINIT, MI_OPTION(use_numa_nodes) },           // 0 = use available numa nodes, otherwise use at most N nodes.
+  { 0,   UNINIT, MI_OPTION(limit_os_alloc) },           // 1 = do not use OS memory for allocation (but only reserved arenas)
+  { 100, UNINIT, MI_OPTION(os_tag) },                   // only apple specific for now but might serve more or less related purpose
+  { 16,  UNINIT, MI_OPTION(max_errors) },               // maximum errors that are output
+  { 16,  UNINIT, MI_OPTION(max_warnings) },             // maximum warnings that are output
+  { 8,   UNINIT, MI_OPTION(max_segment_reclaim)},       // max. number of segment reclaims from the abandoned segments per try.
+  { 0,   UNINIT, MI_OPTION(destroy_on_exit)},           // release all OS memory on process exit; careful with dangling pointer or after-exit frees!
+  #if (MI_INTPTR_SIZE>4)
+  { 1024L * 1024L, UNINIT, MI_OPTION(arena_reserve) },  // reserve memory N KiB at a time
+  #else
+  {  128L * 1024L, UNINIT, MI_OPTION(arena_reserve) },
+  #endif
+  { 10,  UNINIT, MI_OPTION(arena_purge_mult) },        // purge delay multiplier for arena's
+  { 1,   UNINIT, MI_OPTION_LEGACY(purge_extend_delay, decommit_extend_delay) },
+};
+
+static void mi_option_init(mi_option_desc_t* desc);
+
+void _mi_options_init(void) {
+  // called on process load; should not be called before the CRT is initialized!
+  // (e.g. do not call this from process_init as that may run before CRT initialization)
+  mi_add_stderr_output(); // now it safe to use stderr for output
+  for(int i = 0; i < _mi_option_last; i++ ) {
+    mi_option_t option = (mi_option_t)i;
+    long l = mi_option_get(option); MI_UNUSED(l); // initialize
+    // if (option != mi_option_verbose)
+    {
+      mi_option_desc_t* desc = &options[option];
+      _mi_verbose_message("option '%s': %ld\n", desc->name, desc->value);
+    }
+  }
+  mi_max_error_count = mi_option_get(mi_option_max_errors);
+  mi_max_warning_count = mi_option_get(mi_option_max_warnings);
+}
+
+mi_decl_nodiscard long mi_option_get(mi_option_t option) {
+  mi_assert(option >= 0 && option < _mi_option_last);
+  if (option < 0 || option >= _mi_option_last) return 0;
+  mi_option_desc_t* desc = &options[option];
+  mi_assert(desc->option == option);  // index should match the option
+  if mi_unlikely(desc->init == UNINIT) {
+    mi_option_init(desc);
+  }
+  return desc->value;
+}
+
+mi_decl_nodiscard long mi_option_get_clamp(mi_option_t option, long min, long max) {
+  long x = mi_option_get(option);
+  return (x < min ? min : (x > max ? max : x));
+}
+
+mi_decl_nodiscard size_t mi_option_get_size(mi_option_t option) {
+  mi_assert_internal(option == mi_option_reserve_os_memory || option == mi_option_arena_reserve);
+  long x = mi_option_get(option);
+  return (x < 0 ? 0 : (size_t)x * MI_KiB);
+}
+
+void mi_option_set(mi_option_t option, long value) {
+  mi_assert(option >= 0 && option < _mi_option_last);
+  if (option < 0 || option >= _mi_option_last) return;
+  mi_option_desc_t* desc = &options[option];
+  mi_assert(desc->option == option);  // index should match the option
+  desc->value = value;
+  desc->init = INITIALIZED;
+}
+
+void mi_option_set_default(mi_option_t option, long value) {
+  mi_assert(option >= 0 && option < _mi_option_last);
+  if (option < 0 || option >= _mi_option_last) return;
+  mi_option_desc_t* desc = &options[option];
+  if (desc->init != INITIALIZED) {
+    desc->value = value;
+  }
+}
+
+mi_decl_nodiscard bool mi_option_is_enabled(mi_option_t option) {
+  return (mi_option_get(option) != 0);
+}
+
+void mi_option_set_enabled(mi_option_t option, bool enable) {
+  mi_option_set(option, (enable ? 1 : 0));
+}
+
+void mi_option_set_enabled_default(mi_option_t option, bool enable) {
+  mi_option_set_default(option, (enable ? 1 : 0));
+}
+
+void mi_option_enable(mi_option_t option) {
+  mi_option_set_enabled(option,true);
+}
+
+void mi_option_disable(mi_option_t option) {
+  mi_option_set_enabled(option,false);
+}
+
+static void mi_cdecl mi_out_stderr(const char* msg, void* arg) {
+  MI_UNUSED(arg);
+  if (msg != NULL && msg[0] != 0) {
+    _mi_prim_out_stderr(msg);
+  }
+}
+
+// Since an output function can be registered earliest in the `main`
+// function we also buffer output that happens earlier. When
+// an output function is registered it is called immediately with
+// the output up to that point.
+#ifndef MI_MAX_DELAY_OUTPUT
+#define MI_MAX_DELAY_OUTPUT ((size_t)(32*1024))
+#endif
+static char out_buf[MI_MAX_DELAY_OUTPUT+1];
+static _Atomic(size_t) out_len;
+
+static void mi_cdecl mi_out_buf(const char* msg, void* arg) {
+  MI_UNUSED(arg);
+  if (msg==NULL) return;
+  if (mi_atomic_load_relaxed(&out_len)>=MI_MAX_DELAY_OUTPUT) return;
+  size_t n = _mi_strlen(msg);
+  if (n==0) return;
+  // claim space
+  size_t start = mi_atomic_add_acq_rel(&out_len, n);
+  if (start >= MI_MAX_DELAY_OUTPUT) return;
+  // check bound
+  if (start+n >= MI_MAX_DELAY_OUTPUT) {
+    n = MI_MAX_DELAY_OUTPUT-start-1;
+  }
+  _mi_memcpy(&out_buf[start], msg, n);
+}
+
+static void mi_out_buf_flush(mi_output_fun* out, bool no_more_buf, void* arg) {
+  if (out==NULL) return;
+  // claim (if `no_more_buf == true`, no more output will be added after this point)
+  size_t count = mi_atomic_add_acq_rel(&out_len, (no_more_buf ? MI_MAX_DELAY_OUTPUT : 1));
+  // and output the current contents
+  if (count>MI_MAX_DELAY_OUTPUT) count = MI_MAX_DELAY_OUTPUT;
+  out_buf[count] = 0;
+  out(out_buf,arg);
+  if (!no_more_buf) {
+    out_buf[count] = '\n'; // if continue with the buffer, insert a newline
+  }
+}
+
+
+// Once this module is loaded, switch to this routine
+// which outputs to stderr and the delayed output buffer.
+static void mi_cdecl mi_out_buf_stderr(const char* msg, void* arg) {
+  mi_out_stderr(msg,arg);
+  mi_out_buf(msg,arg);
+}
+
+
+
+// --------------------------------------------------------
+// Default output handler
+// --------------------------------------------------------
+
+// Should be atomic but gives errors on many platforms as generally we cannot cast a function pointer to a uintptr_t.
+// For now, don't register output from multiple threads.
+static mi_output_fun* volatile mi_out_default; // = NULL
+static _Atomic(void*) mi_out_arg; // = NULL
+
+static mi_output_fun* mi_out_get_default(void** parg) {
+  if (parg != NULL) { *parg = mi_atomic_load_ptr_acquire(void,&mi_out_arg); }
+  mi_output_fun* out = mi_out_default;
+  return (out == NULL ? &mi_out_buf : out);
+}
+
+void mi_register_output(mi_output_fun* out, void* arg) mi_attr_noexcept {
+  mi_out_default = (out == NULL ? &mi_out_stderr : out); // stop using the delayed output buffer
+  mi_atomic_store_ptr_release(void,&mi_out_arg, arg);
+  if (out!=NULL) mi_out_buf_flush(out,true,arg);         // output all the delayed output now
+}
+
+// add stderr to the delayed output after the module is loaded
+static void mi_add_stderr_output(void) {
+  mi_assert_internal(mi_out_default == NULL);
+  mi_out_buf_flush(&mi_out_stderr, false, NULL); // flush current contents to stderr
+  mi_out_default = &mi_out_buf_stderr;           // and add stderr to the delayed output
+}
+
+// --------------------------------------------------------
+// Messages, all end up calling `_mi_fputs`.
+// --------------------------------------------------------
+static _Atomic(size_t) error_count;   // = 0;  // when >= max_error_count stop emitting errors
+static _Atomic(size_t) warning_count; // = 0;  // when >= max_warning_count stop emitting warnings
+
+// When overriding malloc, we may recurse into mi_vfprintf if an allocation
+// inside the C runtime causes another message.
+// In some cases (like on macOS) the loader already allocates which
+// calls into mimalloc; if we then access thread locals (like `recurse`)
+// this may crash as the access may call _tlv_bootstrap that tries to
+// (recursively) invoke malloc again to allocate space for the thread local
+// variables on demand. This is why we use a _mi_preloading test on such
+// platforms. However, C code generator may move the initial thread local address
+// load before the `if` and we therefore split it out in a separate funcion.
+static mi_decl_thread bool recurse = false;
+
+static mi_decl_noinline bool mi_recurse_enter_prim(void) {
+  if (recurse) return false;
+  recurse = true;
+  return true;
+}
+
+static mi_decl_noinline void mi_recurse_exit_prim(void) {
+  recurse = false;
+}
+
+static bool mi_recurse_enter(void) {
+  #if defined(__APPLE__) || defined(MI_TLS_RECURSE_GUARD)
+  if (_mi_preloading()) return false;
+  #endif
+  return mi_recurse_enter_prim();
+}
+
+static void mi_recurse_exit(void) {
+  #if defined(__APPLE__) || defined(MI_TLS_RECURSE_GUARD)
+  if (_mi_preloading()) return;
+  #endif
+  mi_recurse_exit_prim();
+}
+
+void _mi_fputs(mi_output_fun* out, void* arg, const char* prefix, const char* message) {
+  if (out==NULL || (void*)out==(void*)stdout || (void*)out==(void*)stderr) { // TODO: use mi_out_stderr for stderr?
+    if (!mi_recurse_enter()) return;
+    out = mi_out_get_default(&arg);
+    if (prefix != NULL) out(prefix, arg);
+    out(message, arg);
+    mi_recurse_exit();
+  }
+  else {
+    if (prefix != NULL) out(prefix, arg);
+    out(message, arg);
+  }
+}
+
+// Define our own limited `fprintf` that avoids memory allocation.
+// We do this using `snprintf` with a limited buffer.
+static void mi_vfprintf( mi_output_fun* out, void* arg, const char* prefix, const char* fmt, va_list args ) {
+  char buf[512];
+  if (fmt==NULL) return;
+  if (!mi_recurse_enter()) return;
+  vsnprintf(buf,sizeof(buf)-1,fmt,args);
+  mi_recurse_exit();
+  _mi_fputs(out,arg,prefix,buf);
+}
+
+void _mi_fprintf( mi_output_fun* out, void* arg, const char* fmt, ... ) {
+  va_list args;
+  va_start(args,fmt);
+  mi_vfprintf(out,arg,NULL,fmt,args);
+  va_end(args);
+}
+
+static void mi_vfprintf_thread(mi_output_fun* out, void* arg, const char* prefix, const char* fmt, va_list args) {
+  if (prefix != NULL && _mi_strnlen(prefix,33) <= 32 && !_mi_is_main_thread()) {
+    char tprefix[64];
+    snprintf(tprefix, sizeof(tprefix), "%sthread 0x%llx: ", prefix, (unsigned long long)_mi_thread_id());
+    mi_vfprintf(out, arg, tprefix, fmt, args);
+  }
+  else {
+    mi_vfprintf(out, arg, prefix, fmt, args);
+  }
+}
+
+void _mi_trace_message(const char* fmt, ...) {
+  if (mi_option_get(mi_option_verbose) <= 1) return;  // only with verbose level 2 or higher
+  va_list args;
+  va_start(args, fmt);
+  mi_vfprintf_thread(NULL, NULL, "mimalloc: ", fmt, args);
+  va_end(args);
+}
+
+void _mi_verbose_message(const char* fmt, ...) {
+  if (!mi_option_is_enabled(mi_option_verbose)) return;
+  va_list args;
+  va_start(args,fmt);
+  mi_vfprintf(NULL, NULL, "mimalloc: ", fmt, args);
+  va_end(args);
+}
+
+static void mi_show_error_message(const char* fmt, va_list args) {
+  if (!mi_option_is_enabled(mi_option_verbose)) {
+    if (!mi_option_is_enabled(mi_option_show_errors)) return;
+    if (mi_max_error_count >= 0 && (long)mi_atomic_increment_acq_rel(&error_count) > mi_max_error_count) return;
+  }
+  mi_vfprintf_thread(NULL, NULL, "mimalloc: error: ", fmt, args);
+}
+
+void _mi_warning_message(const char* fmt, ...) {
+  if (!mi_option_is_enabled(mi_option_verbose)) {
+    if (!mi_option_is_enabled(mi_option_show_errors)) return;
+    if (mi_max_warning_count >= 0 && (long)mi_atomic_increment_acq_rel(&warning_count) > mi_max_warning_count) return;
+  }
+  va_list args;
+  va_start(args,fmt);
+  mi_vfprintf_thread(NULL, NULL, "mimalloc: warning: ", fmt, args);
+  va_end(args);
+}
+
+
+#if MI_DEBUG
+void _mi_assert_fail(const char* assertion, const char* fname, unsigned line, const char* func ) {
+  _mi_fprintf(NULL, NULL, "mimalloc: assertion failed: at \"%s\":%u, %s\n  assertion: \"%s\"\n", fname, line, (func==NULL?"":func), assertion);
+  abort();
+}
+#endif
+
+// --------------------------------------------------------
+// Errors
+// --------------------------------------------------------
+
+static mi_error_fun* volatile  mi_error_handler; // = NULL
+static _Atomic(void*) mi_error_arg;     // = NULL
+
+static void mi_error_default(int err) {
+  MI_UNUSED(err);
+#if (MI_DEBUG>0)
+  if (err==EFAULT) {
+    #ifdef _MSC_VER
+    __debugbreak();
+    #endif
+    abort();
+  }
+#endif
+#if (MI_SECURE>0)
+  if (err==EFAULT) {  // abort on serious errors in secure mode (corrupted meta-data)
+    abort();
+  }
+#endif
+#if defined(MI_XMALLOC)
+  if (err==ENOMEM || err==EOVERFLOW) { // abort on memory allocation fails in xmalloc mode
+    abort();
+  }
+#endif
+}
+
+void mi_register_error(mi_error_fun* fun, void* arg) {
+  mi_error_handler = fun;  // can be NULL
+  mi_atomic_store_ptr_release(void,&mi_error_arg, arg);
+}
+
+void _mi_error_message(int err, const char* fmt, ...) {
+  // show detailed error message
+  va_list args;
+  va_start(args, fmt);
+  mi_show_error_message(fmt, args);
+  va_end(args);
+  // and call the error handler which may abort (or return normally)
+  if (mi_error_handler != NULL) {
+    mi_error_handler(err, mi_atomic_load_ptr_acquire(void,&mi_error_arg));
+  }
+  else {
+    mi_error_default(err);
+  }
+}
+
+// --------------------------------------------------------
+// Initialize options by checking the environment
+// --------------------------------------------------------
+char _mi_toupper(char c) {
+  if (c >= 'a' && c <= 'z') return (c - 'a' + 'A');
+		       else return c;
+}
+
+int _mi_strnicmp(const char* s, const char* t, size_t n) {
+  if (n == 0) return 0;
+  for (; *s != 0 && *t != 0 && n > 0; s++, t++, n--) {
+    if (_mi_toupper(*s) != _mi_toupper(*t)) break;
+  }
+  return (n == 0 ? 0 : *s - *t);
+}
+
+void _mi_strlcpy(char* dest, const char* src, size_t dest_size) {
+  if (dest==NULL || src==NULL || dest_size == 0) return;
+  // copy until end of src, or when dest is (almost) full
+  while (*src != 0 && dest_size > 1) {
+    *dest++ = *src++;
+    dest_size--;
+  }
+  // always zero terminate
+  *dest = 0;
+}
+
+void _mi_strlcat(char* dest, const char* src, size_t dest_size) {
+  if (dest==NULL || src==NULL || dest_size == 0) return;
+  // find end of string in the dest buffer
+  while (*dest != 0 && dest_size > 1) {
+    dest++;
+    dest_size--;
+  }
+  // and catenate
+  _mi_strlcpy(dest, src, dest_size);
+}
+
+size_t _mi_strlen(const char* s) {
+  if (s==NULL) return 0;
+  size_t len = 0;
+  while(s[len] != 0) { len++; }
+  return len;
+}
+
+size_t _mi_strnlen(const char* s, size_t max_len) {
+  if (s==NULL) return 0;
+  size_t len = 0;
+  while(s[len] != 0 && len < max_len) { len++; }
+  return len;
+}
+
+#ifdef MI_NO_GETENV
+static bool mi_getenv(const char* name, char* result, size_t result_size) {
+  MI_UNUSED(name);
+  MI_UNUSED(result);
+  MI_UNUSED(result_size);
+  return false;
+}
+#else
+static bool mi_getenv(const char* name, char* result, size_t result_size) {
+  if (name==NULL || result == NULL || result_size < 64) return false;
+  return _mi_prim_getenv(name,result,result_size);
+}
+#endif
+
+// TODO: implement ourselves to reduce dependencies on the C runtime
+#include <stdlib.h> // strtol
+#include <string.h> // strstr
+
+
+static void mi_option_init(mi_option_desc_t* desc) {
+  // Read option value from the environment
+  char s[64 + 1];
+  char buf[64+1];
+  _mi_strlcpy(buf, "mimalloc_", sizeof(buf));
+  _mi_strlcat(buf, desc->name, sizeof(buf));
+  bool found = mi_getenv(buf, s, sizeof(s));
+  if (!found && desc->legacy_name != NULL) {
+    _mi_strlcpy(buf, "mimalloc_", sizeof(buf));
+    _mi_strlcat(buf, desc->legacy_name, sizeof(buf));
+    found = mi_getenv(buf, s, sizeof(s));
+    if (found) {
+      _mi_warning_message("environment option \"mimalloc_%s\" is deprecated -- use \"mimalloc_%s\" instead.\n", desc->legacy_name, desc->name);
+    }
+  }
+
+  if (found) {
+    size_t len = _mi_strnlen(s, sizeof(buf) - 1);
+    for (size_t i = 0; i < len; i++) {
+      buf[i] = _mi_toupper(s[i]);
+    }
+    buf[len] = 0;
+    if (buf[0] == 0 || strstr("1;TRUE;YES;ON", buf) != NULL) {
+      desc->value = 1;
+      desc->init = INITIALIZED;
+    }
+    else if (strstr("0;FALSE;NO;OFF", buf) != NULL) {
+      desc->value = 0;
+      desc->init = INITIALIZED;
+    }
+    else {
+      char* end = buf;
+      long value = strtol(buf, &end, 10);
+      if (desc->option == mi_option_reserve_os_memory || desc->option == mi_option_arena_reserve) {
+	// this option is interpreted in KiB to prevent overflow of `long`
+	if (*end == 'K') { end++; }
+	else if (*end == 'M') { value *= MI_KiB; end++; }
+	else if (*end == 'G') { value *= MI_MiB; end++; }
+	else { value = (value + MI_KiB - 1) / MI_KiB; }
+	if (end[0] == 'I' && end[1] == 'B') { end += 2; }
+	else if (*end == 'B') { end++; }
+      }
+      if (*end == 0) {
+	desc->value = value;
+	desc->init = INITIALIZED;
+      }
+      else {
+	// set `init` first to avoid recursion through _mi_warning_message on mimalloc_verbose.
+	desc->init = DEFAULTED;
+	if (desc->option == mi_option_verbose && desc->value == 0) {
+	  // if the 'mimalloc_verbose' env var has a bogus value we'd never know
+	  // (since the value defaults to 'off') so in that case briefly enable verbose
+	  desc->value = 1;
+	  _mi_warning_message("environment option mimalloc_%s has an invalid value.\n", desc->name);
+	  desc->value = 0;
+	}
+	else {
+	  _mi_warning_message("environment option mimalloc_%s has an invalid value.\n", desc->name);
+	}
+      }
+    }
+    mi_assert_internal(desc->init != UNINIT);
+  }
+  else if (!_mi_preloading()) {
+    desc->init = DEFAULTED;
+  }
+}
diff --git a/compat/mimalloc/os.c b/compat/mimalloc/os.c
new file mode 100644
index 00000000000000..bf9de1be0fdb49
--- /dev/null
+++ b/compat/mimalloc/os.c
@@ -0,0 +1,689 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2023, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "mimalloc/atomic.h"
+#include "mimalloc/prim.h"
+
+
+/* -----------------------------------------------------------
+  Initialization.
+  On windows initializes support for aligned allocation and
+  large OS pages (if MIMALLOC_LARGE_OS_PAGES is true).
+----------------------------------------------------------- */
+
+static mi_os_mem_config_t mi_os_mem_config = {
+  4096,   // page size
+  0,      // large page size (usually 2MiB)
+  4096,   // allocation granularity
+  true,   // has overcommit?  (if true we use MAP_NORESERVE on mmap systems)
+  false,  // must free whole? (on mmap systems we can free anywhere in a mapped range, but on Windows we must free the entire span)
+  true    // has virtual reserve? (if true we can reserve virtual address space without using commit or physical memory)
+};
+
+bool _mi_os_has_overcommit(void) {
+  return mi_os_mem_config.has_overcommit;
+}
+
+bool _mi_os_has_virtual_reserve(void) {
+  return mi_os_mem_config.has_virtual_reserve;
+}
+
+
+// OS (small) page size
+size_t _mi_os_page_size(void) {
+  return mi_os_mem_config.page_size;
+}
+
+// if large OS pages are supported (2 or 4MiB), then return the size, otherwise return the small page size (4KiB)
+size_t _mi_os_large_page_size(void) {
+  return (mi_os_mem_config.large_page_size != 0 ? mi_os_mem_config.large_page_size : _mi_os_page_size());
+}
+
+bool _mi_os_use_large_page(size_t size, size_t alignment) {
+  // if we have access, check the size and alignment requirements
+  if (mi_os_mem_config.large_page_size == 0 || !mi_option_is_enabled(mi_option_allow_large_os_pages)) return false;
+  return ((size % mi_os_mem_config.large_page_size) == 0 && (alignment % mi_os_mem_config.large_page_size) == 0);
+}
+
+// round to a good OS allocation size (bounded by max 12.5% waste)
+size_t _mi_os_good_alloc_size(size_t size) {
+  size_t align_size;
+  if (size < 512*MI_KiB) align_size = _mi_os_page_size();
+  else if (size < 2*MI_MiB) align_size = 64*MI_KiB;
+  else if (size < 8*MI_MiB) align_size = 256*MI_KiB;
+  else if (size < 32*MI_MiB) align_size = 1*MI_MiB;
+  else align_size = 4*MI_MiB;
+  if mi_unlikely(size >= (SIZE_MAX - align_size)) return size; // possible overflow?
+  return _mi_align_up(size, align_size);
+}
+
+void _mi_os_init(void) {
+  _mi_prim_mem_init(&mi_os_mem_config);
+}
+
+
+/* -----------------------------------------------------------
+  Util
+-------------------------------------------------------------- */
+bool _mi_os_decommit(void* addr, size_t size, mi_stats_t* stats);
+bool _mi_os_commit(void* addr, size_t size, bool* is_zero, mi_stats_t* tld_stats);
+
+static void* mi_align_up_ptr(void* p, size_t alignment) {
+  return (void*)_mi_align_up((uintptr_t)p, alignment);
+}
+
+static void* mi_align_down_ptr(void* p, size_t alignment) {
+  return (void*)_mi_align_down((uintptr_t)p, alignment);
+}
+
+
+/* -----------------------------------------------------------
+  aligned hinting
+-------------------------------------------------------------- */
+
+// On 64-bit systems, we can do efficient aligned allocation by using
+// the 2TiB to 30TiB area to allocate those.
+#if (MI_INTPTR_SIZE >= 8)
+static mi_decl_cache_align _Atomic(uintptr_t)aligned_base;
+
+// Return a MI_SEGMENT_SIZE aligned address that is probably available.
+// If this returns NULL, the OS will determine the address but on some OS's that may not be
+// properly aligned which can be more costly as it needs to be adjusted afterwards.
+// For a size > 1GiB this always returns NULL in order to guarantee good ASLR randomization;
+// (otherwise an initial large allocation of say 2TiB has a 50% chance to include (known) addresses
+//  in the middle of the 2TiB - 6TiB address range (see issue #372))
+
+#define MI_HINT_BASE ((uintptr_t)2 << 40)  // 2TiB start
+#define MI_HINT_AREA ((uintptr_t)4 << 40)  // upto 6TiB   (since before win8 there is "only" 8TiB available to processes)
+#define MI_HINT_MAX  ((uintptr_t)30 << 40) // wrap after 30TiB (area after 32TiB is used for huge OS pages)
+
+void* _mi_os_get_aligned_hint(size_t try_alignment, size_t size)
+{
+  if (try_alignment <= 1 || try_alignment > MI_SEGMENT_SIZE) return NULL;
+  size = _mi_align_up(size, MI_SEGMENT_SIZE);
+  if (size > 1*MI_GiB) return NULL;  // guarantee the chance of fixed valid address is at most 1/(MI_HINT_AREA / 1<<30) = 1/4096.
+  #if (MI_SECURE>0)
+  size += MI_SEGMENT_SIZE;        // put in `MI_SEGMENT_SIZE` virtual gaps between hinted blocks; this splits VLA's but increases guarded areas.
+  #endif
+
+  uintptr_t hint = mi_atomic_add_acq_rel(&aligned_base, size);
+  if (hint == 0 || hint > MI_HINT_MAX) {   // wrap or initialize
+    uintptr_t init = MI_HINT_BASE;
+    #if (MI_SECURE>0 || MI_DEBUG==0)       // security: randomize start of aligned allocations unless in debug mode
+    uintptr_t r = _mi_heap_random_next(mi_prim_get_default_heap());
+    init = init + ((MI_SEGMENT_SIZE * ((r>>17) & 0xFFFFF)) % MI_HINT_AREA);  // (randomly 20 bits)*4MiB == 0 to 4TiB
+    #endif
+    uintptr_t expected = hint + size;
+    mi_atomic_cas_strong_acq_rel(&aligned_base, &expected, init);
+    hint = mi_atomic_add_acq_rel(&aligned_base, size); // this may still give 0 or > MI_HINT_MAX but that is ok, it is a hint after all
+  }
+  if (hint%try_alignment != 0) return NULL;
+  return (void*)hint;
+}
+#else
+void* _mi_os_get_aligned_hint(size_t try_alignment, size_t size) {
+  MI_UNUSED(try_alignment); MI_UNUSED(size);
+  return NULL;
+}
+#endif
+
+
+/* -----------------------------------------------------------
+  Free memory
+-------------------------------------------------------------- */
+
+static void mi_os_free_huge_os_pages(void* p, size_t size, mi_stats_t* stats);
+
+static void mi_os_prim_free(void* addr, size_t size, bool still_committed, mi_stats_t* tld_stats) {
+  MI_UNUSED(tld_stats);
+  mi_assert_internal((size % _mi_os_page_size()) == 0);
+  if (addr == NULL || size == 0) return; // || _mi_os_is_huge_reserved(addr)
+  int err = _mi_prim_free(addr, size);
+  if (err != 0) {
+    _mi_warning_message("unable to free OS memory (error: %d (0x%x), size: 0x%zx bytes, address: %p)\n", err, err, size, addr);
+  }
+  mi_stats_t* stats = &_mi_stats_main;
+  if (still_committed) { _mi_stat_decrease(&stats->committed, size); }
+  _mi_stat_decrease(&stats->reserved, size);
+}
+
+void _mi_os_free_ex(void* addr, size_t size, bool still_committed, mi_memid_t memid, mi_stats_t* tld_stats) {
+  if (mi_memkind_is_os(memid.memkind)) {
+    size_t csize = _mi_os_good_alloc_size(size);
+    void* base = addr;
+    // different base? (due to alignment)
+    if (memid.mem.os.base != NULL) {
+      mi_assert(memid.mem.os.base <= addr);
+      mi_assert((uint8_t*)memid.mem.os.base + memid.mem.os.alignment >= (uint8_t*)addr);
+      base = memid.mem.os.base;
+      csize += ((uint8_t*)addr - (uint8_t*)memid.mem.os.base);
+    }
+    // free it
+    if (memid.memkind == MI_MEM_OS_HUGE) {
+      mi_assert(memid.is_pinned);
+      mi_os_free_huge_os_pages(base, csize, tld_stats);
+    }
+    else {
+      mi_os_prim_free(base, csize, still_committed, tld_stats);
+    }
+  }
+  else {
+    // nothing to do
+    mi_assert(memid.memkind < MI_MEM_OS);
+  }
+}
+
+void  _mi_os_free(void* p, size_t size, mi_memid_t memid, mi_stats_t* tld_stats) {
+  _mi_os_free_ex(p, size, true, memid, tld_stats);
+}
+
+
+/* -----------------------------------------------------------
+   Primitive allocation from the OS.
+-------------------------------------------------------------- */
+
+// Note: the `try_alignment` is just a hint and the returned pointer is not guaranteed to be aligned.
+static void* mi_os_prim_alloc(size_t size, size_t try_alignment, bool commit, bool allow_large, bool* is_large, bool* is_zero, mi_stats_t* stats) {
+  mi_assert_internal(size > 0 && (size % _mi_os_page_size()) == 0);
+  mi_assert_internal(is_zero != NULL);
+  mi_assert_internal(is_large != NULL);
+  if (size == 0) return NULL;
+  if (!commit) { allow_large = false; }
+  if (try_alignment == 0) { try_alignment = 1; } // avoid 0 to ensure there will be no divide by zero when aligning
+
+  *is_zero = false;
+  void* p = NULL;
+  int err = _mi_prim_alloc(size, try_alignment, commit, allow_large, is_large, is_zero, &p);
+  if (err != 0) {
+    _mi_warning_message("unable to allocate OS memory (error: %d (0x%x), size: 0x%zx bytes, align: 0x%zx, commit: %d, allow large: %d)\n", err, err, size, try_alignment, commit, allow_large);
+  }
+  mi_stat_counter_increase(stats->mmap_calls, 1);
+  if (p != NULL) {
+    _mi_stat_increase(&stats->reserved, size);
+    if (commit) {
+      _mi_stat_increase(&stats->committed, size);
+      // seems needed for asan (or `mimalloc-test-api` fails)
+      #ifdef MI_TRACK_ASAN
+      if (*is_zero) { mi_track_mem_defined(p,size); }
+	       else { mi_track_mem_undefined(p,size); }
+      #endif
+    }
+  }
+  return p;
+}
+
+
+// Primitive aligned allocation from the OS.
+// This function guarantees the allocated memory is aligned.
+static void* mi_os_prim_alloc_aligned(size_t size, size_t alignment, bool commit, bool allow_large, bool* is_large, bool* is_zero, void** base, mi_stats_t* stats) {
+  mi_assert_internal(alignment >= _mi_os_page_size() && ((alignment & (alignment - 1)) == 0));
+  mi_assert_internal(size > 0 && (size % _mi_os_page_size()) == 0);
+  mi_assert_internal(is_large != NULL);
+  mi_assert_internal(is_zero != NULL);
+  mi_assert_internal(base != NULL);
+  if (!commit) allow_large = false;
+  if (!(alignment >= _mi_os_page_size() && ((alignment & (alignment - 1)) == 0))) return NULL;
+  size = _mi_align_up(size, _mi_os_page_size());
+
+  // try first with a hint (this will be aligned directly on Win 10+ or BSD)
+  void* p = mi_os_prim_alloc(size, alignment, commit, allow_large, is_large, is_zero, stats);
+  if (p == NULL) return NULL;
+
+  // aligned already?
+  if (((uintptr_t)p % alignment) == 0) {
+    *base = p;
+  }
+  else {
+    // if not aligned, free it, overallocate, and unmap around it
+    _mi_warning_message("unable to allocate aligned OS memory directly, fall back to over-allocation (size: 0x%zx bytes, address: %p, alignment: 0x%zx, commit: %d)\n", size, p, alignment, commit);
+    mi_os_prim_free(p, size, commit, stats);
+    if (size >= (SIZE_MAX - alignment)) return NULL; // overflow
+    const size_t over_size = size + alignment;
+
+    if (mi_os_mem_config.must_free_whole) {  // win32 virtualAlloc cannot free parts of an allocate block
+      // over-allocate uncommitted (virtual) memory
+      p = mi_os_prim_alloc(over_size, 1 /*alignment*/, false /* commit? */, false /* allow_large */, is_large, is_zero, stats);
+      if (p == NULL) return NULL;
+
+      // set p to the aligned part in the full region
+      // note: this is dangerous on Windows as VirtualFree needs the actual base pointer
+      // this is handled though by having the `base` field in the memid's
+      *base = p; // remember the base
+      p = mi_align_up_ptr(p, alignment);
+
+      // explicitly commit only the aligned part
+      if (commit) {
+	_mi_os_commit(p, size, NULL, stats);
+      }
+    }
+    else  { // mmap can free inside an allocation
+      // overallocate...
+      p = mi_os_prim_alloc(over_size, 1, commit, false, is_large, is_zero, stats);
+      if (p == NULL) return NULL;
+
+      // and selectively unmap parts around the over-allocated area. (noop on sbrk)
+      void* aligned_p = mi_align_up_ptr(p, alignment);
+      size_t pre_size = (uint8_t*)aligned_p - (uint8_t*)p;
+      size_t mid_size = _mi_align_up(size, _mi_os_page_size());
+      size_t post_size = over_size - pre_size - mid_size;
+      mi_assert_internal(pre_size < over_size&& post_size < over_size&& mid_size >= size);
+      if (pre_size > 0)  { mi_os_prim_free(p, pre_size, commit, stats); }
+      if (post_size > 0) { mi_os_prim_free((uint8_t*)aligned_p + mid_size, post_size, commit, stats); }
+      // we can return the aligned pointer on `mmap` (and sbrk) systems
+      p = aligned_p;
+      *base = aligned_p; // since we freed the pre part, `*base == p`.
+    }
+  }
+
+  mi_assert_internal(p == NULL || (p != NULL && *base != NULL && ((uintptr_t)p % alignment) == 0));
+  return p;
+}
+
+
+/* -----------------------------------------------------------
+  OS API: alloc and alloc_aligned
+----------------------------------------------------------- */
+
+void* _mi_os_alloc(size_t size, mi_memid_t* memid, mi_stats_t* tld_stats) {
+  MI_UNUSED(tld_stats);
+  *memid = _mi_memid_none();
+  mi_stats_t* stats = &_mi_stats_main;
+  if (size == 0) return NULL;
+  size = _mi_os_good_alloc_size(size);
+  bool os_is_large = false;
+  bool os_is_zero  = false;
+  void* p = mi_os_prim_alloc(size, 0, true, false, &os_is_large, &os_is_zero, stats);
+  if (p != NULL) {
+    *memid = _mi_memid_create_os(true, os_is_zero, os_is_large);
+  }
+  return p;
+}
+
+void* _mi_os_alloc_aligned(size_t size, size_t alignment, bool commit, bool allow_large, mi_memid_t* memid, mi_stats_t* tld_stats)
+{
+  MI_UNUSED(&_mi_os_get_aligned_hint); // suppress unused warnings
+  MI_UNUSED(tld_stats);
+  *memid = _mi_memid_none();
+  if (size == 0) return NULL;
+  size = _mi_os_good_alloc_size(size);
+  alignment = _mi_align_up(alignment, _mi_os_page_size());
+
+  bool os_is_large = false;
+  bool os_is_zero  = false;
+  void* os_base = NULL;
+  void* p = mi_os_prim_alloc_aligned(size, alignment, commit, allow_large, &os_is_large, &os_is_zero, &os_base, &_mi_stats_main /*tld->stats*/ );
+  if (p != NULL) {
+    *memid = _mi_memid_create_os(commit, os_is_zero, os_is_large);
+    memid->mem.os.base = os_base;
+    memid->mem.os.alignment = alignment;
+  }
+  return p;
+}
+
+/* -----------------------------------------------------------
+  OS aligned allocation with an offset. This is used
+  for large alignments > MI_ALIGNMENT_MAX. We use a large mimalloc
+  page where the object can be aligned at an offset from the start of the segment.
+  As we may need to overallocate, we need to free such pointers using `mi_free_aligned`
+  to use the actual start of the memory region.
+----------------------------------------------------------- */
+
+void* _mi_os_alloc_aligned_at_offset(size_t size, size_t alignment, size_t offset, bool commit, bool allow_large, mi_memid_t* memid, mi_stats_t* tld_stats) {
+  mi_assert(offset <= MI_SEGMENT_SIZE);
+  mi_assert(offset <= size);
+  mi_assert((alignment % _mi_os_page_size()) == 0);
+  *memid = _mi_memid_none();
+  if (offset > MI_SEGMENT_SIZE) return NULL;
+  if (offset == 0) {
+    // regular aligned allocation
+    return _mi_os_alloc_aligned(size, alignment, commit, allow_large, memid, tld_stats);
+  }
+  else {
+    // overallocate to align at an offset
+    const size_t extra = _mi_align_up(offset, alignment) - offset;
+    const size_t oversize = size + extra;
+    void* const start = _mi_os_alloc_aligned(oversize, alignment, commit, allow_large, memid, tld_stats);
+    if (start == NULL) return NULL;
+
+    void* const p = (uint8_t*)start + extra;
+    mi_assert(_mi_is_aligned((uint8_t*)p + offset, alignment));
+    // decommit the overallocation at the start
+    if (commit && extra > _mi_os_page_size()) {
+      _mi_os_decommit(start, extra, tld_stats);
+    }
+    return p;
+  }
+}
+
+/* -----------------------------------------------------------
+  OS memory API: reset, commit, decommit, protect, unprotect.
+----------------------------------------------------------- */
+
+// OS page align within a given area, either conservative (pages inside the area only),
+// or not (straddling pages outside the area is possible)
+static void* mi_os_page_align_areax(bool conservative, void* addr, size_t size, size_t* newsize) {
+  mi_assert(addr != NULL && size > 0);
+  if (newsize != NULL) *newsize = 0;
+  if (size == 0 || addr == NULL) return NULL;
+
+  // page align conservatively within the range
+  void* start = (conservative ? mi_align_up_ptr(addr, _mi_os_page_size())
+    : mi_align_down_ptr(addr, _mi_os_page_size()));
+  void* end = (conservative ? mi_align_down_ptr((uint8_t*)addr + size, _mi_os_page_size())
+    : mi_align_up_ptr((uint8_t*)addr + size, _mi_os_page_size()));
+  ptrdiff_t diff = (uint8_t*)end - (uint8_t*)start;
+  if (diff <= 0) return NULL;
+
+  mi_assert_internal((conservative && (size_t)diff <= size) || (!conservative && (size_t)diff >= size));
+  if (newsize != NULL) *newsize = (size_t)diff;
+  return start;
+}
+
+static void* mi_os_page_align_area_conservative(void* addr, size_t size, size_t* newsize) {
+  return mi_os_page_align_areax(true, addr, size, newsize);
+}
+
+bool _mi_os_commit(void* addr, size_t size, bool* is_zero, mi_stats_t* tld_stats) {
+  MI_UNUSED(tld_stats);
+  mi_stats_t* stats = &_mi_stats_main;
+  if (is_zero != NULL) { *is_zero = false; }
+  _mi_stat_increase(&stats->committed, size);  // use size for precise commit vs. decommit
+  _mi_stat_counter_increase(&stats->commit_calls, 1);
+
+  // page align range
+  size_t csize;
+  void* start = mi_os_page_align_areax(false /* conservative? */, addr, size, &csize);
+  if (csize == 0) return true;
+
+  // commit
+  bool os_is_zero = false;
+  int err = _mi_prim_commit(start, csize, &os_is_zero);
+  if (err != 0) {
+    _mi_warning_message("cannot commit OS memory (error: %d (0x%x), address: %p, size: 0x%zx bytes)\n", err, err, start, csize);
+    return false;
+  }
+  if (os_is_zero && is_zero != NULL) {
+    *is_zero = true;
+    mi_assert_expensive(mi_mem_is_zero(start, csize));
+  }
+  // note: the following seems required for asan (otherwise `mimalloc-test-stress` fails)
+  #ifdef MI_TRACK_ASAN
+  if (os_is_zero) { mi_track_mem_defined(start,csize); }
+	     else { mi_track_mem_undefined(start,csize); }
+  #endif
+  return true;
+}
+
+static bool mi_os_decommit_ex(void* addr, size_t size, bool* needs_recommit, mi_stats_t* tld_stats) {
+  MI_UNUSED(tld_stats);
+  mi_stats_t* stats = &_mi_stats_main;
+  mi_assert_internal(needs_recommit!=NULL);
+  _mi_stat_decrease(&stats->committed, size);
+
+  // page align
+  size_t csize;
+  void* start = mi_os_page_align_area_conservative(addr, size, &csize);
+  if (csize == 0) return true;
+
+  // decommit
+  *needs_recommit = true;
+  int err = _mi_prim_decommit(start,csize,needs_recommit);
+  if (err != 0) {
+    _mi_warning_message("cannot decommit OS memory (error: %d (0x%x), address: %p, size: 0x%zx bytes)\n", err, err, start, csize);
+  }
+  mi_assert_internal(err == 0);
+  return (err == 0);
+}
+
+bool _mi_os_decommit(void* addr, size_t size, mi_stats_t* tld_stats) {
+  bool needs_recommit;
+  return mi_os_decommit_ex(addr, size, &needs_recommit, tld_stats);
+}
+
+
+// Signal to the OS that the address range is no longer in use
+// but may be used later again. This will release physical memory
+// pages and reduce swapping while keeping the memory committed.
+// We page align to a conservative area inside the range to reset.
+bool _mi_os_reset(void* addr, size_t size, mi_stats_t* stats) {
+  // page align conservatively within the range
+  size_t csize;
+  void* start = mi_os_page_align_area_conservative(addr, size, &csize);
+  if (csize == 0) return true;  // || _mi_os_is_huge_reserved(addr)
+  _mi_stat_increase(&stats->reset, csize);
+  _mi_stat_counter_increase(&stats->reset_calls, 1);
+
+  #if (MI_DEBUG>1) && !MI_SECURE && !MI_TRACK_ENABLED // && !MI_TSAN
+  memset(start, 0, csize); // pretend it is eagerly reset
+  #endif
+
+  int err = _mi_prim_reset(start, csize);
+  if (err != 0) {
+    _mi_warning_message("cannot reset OS memory (error: %d (0x%x), address: %p, size: 0x%zx bytes)\n", err, err, start, csize);
+  }
+  return (err == 0);
+}
+
+
+// either resets or decommits memory, returns true if the memory needs
+// to be recommitted if it is to be re-used later on.
+bool _mi_os_purge_ex(void* p, size_t size, bool allow_reset, mi_stats_t* stats)
+{
+  if (mi_option_get(mi_option_purge_delay) < 0) return false;  // is purging allowed?
+  _mi_stat_counter_increase(&stats->purge_calls, 1);
+  _mi_stat_increase(&stats->purged, size);
+
+  if (mi_option_is_enabled(mi_option_purge_decommits) &&   // should decommit?
+      !_mi_preloading())                                   // don't decommit during preloading (unsafe)
+  {
+    bool needs_recommit = true;
+    mi_os_decommit_ex(p, size, &needs_recommit, stats);
+    return needs_recommit;
+  }
+  else {
+    if (allow_reset) {  // this can sometimes be not allowed if the range is not fully committed
+      _mi_os_reset(p, size, stats);
+    }
+    return false;  // needs no recommit
+  }
+}
+
+// either resets or decommits memory, returns true if the memory needs
+// to be recommitted if it is to be re-used later on.
+bool _mi_os_purge(void* p, size_t size, mi_stats_t * stats) {
+  return _mi_os_purge_ex(p, size, true, stats);
+}
+
+// Protect a region in memory to be not accessible.
+static  bool mi_os_protectx(void* addr, size_t size, bool protect) {
+  // page align conservatively within the range
+  size_t csize = 0;
+  void* start = mi_os_page_align_area_conservative(addr, size, &csize);
+  if (csize == 0) return false;
+  /*
+  if (_mi_os_is_huge_reserved(addr)) {
+	  _mi_warning_message("cannot mprotect memory allocated in huge OS pages\n");
+  }
+  */
+  int err = _mi_prim_protect(start,csize,protect);
+  if (err != 0) {
+    _mi_warning_message("cannot %s OS memory (error: %d (0x%x), address: %p, size: 0x%zx bytes)\n", (protect ? "protect" : "unprotect"), err, err, start, csize);
+  }
+  return (err == 0);
+}
+
+bool _mi_os_protect(void* addr, size_t size) {
+  return mi_os_protectx(addr, size, true);
+}
+
+bool _mi_os_unprotect(void* addr, size_t size) {
+  return mi_os_protectx(addr, size, false);
+}
+
+
+
+/* ----------------------------------------------------------------------------
+Support for allocating huge OS pages (1Gib) that are reserved up-front
+and possibly associated with a specific NUMA node. (use `numa_node>=0`)
+-----------------------------------------------------------------------------*/
+#define MI_HUGE_OS_PAGE_SIZE  (MI_GiB)
+
+
+#if (MI_INTPTR_SIZE >= 8)
+// To ensure proper alignment, use our own area for huge OS pages
+static mi_decl_cache_align _Atomic(uintptr_t)  mi_huge_start; // = 0
+
+// Claim an aligned address range for huge pages
+static uint8_t* mi_os_claim_huge_pages(size_t pages, size_t* total_size) {
+  if (total_size != NULL) *total_size = 0;
+  const size_t size = pages * MI_HUGE_OS_PAGE_SIZE;
+
+  uintptr_t start = 0;
+  uintptr_t end = 0;
+  uintptr_t huge_start = mi_atomic_load_relaxed(&mi_huge_start);
+  do {
+    start = huge_start;
+    if (start == 0) {
+      // Initialize the start address after the 32TiB area
+      start = ((uintptr_t)32 << 40);  // 32TiB virtual start address
+    #if (MI_SECURE>0 || MI_DEBUG==0)      // security: randomize start of huge pages unless in debug mode
+      uintptr_t r = _mi_heap_random_next(mi_prim_get_default_heap());
+      start = start + ((uintptr_t)MI_HUGE_OS_PAGE_SIZE * ((r>>17) & 0x0FFF));  // (randomly 12bits)*1GiB == between 0 to 4TiB
+    #endif
+    }
+    end = start + size;
+    mi_assert_internal(end % MI_SEGMENT_SIZE == 0);
+  } while (!mi_atomic_cas_strong_acq_rel(&mi_huge_start, &huge_start, end));
+
+  if (total_size != NULL) *total_size = size;
+  return (uint8_t*)start;
+}
+#else
+static uint8_t* mi_os_claim_huge_pages(size_t pages, size_t* total_size) {
+  MI_UNUSED(pages);
+  if (total_size != NULL) *total_size = 0;
+  return NULL;
+}
+#endif
+
+// Allocate MI_SEGMENT_SIZE aligned huge pages
+void* _mi_os_alloc_huge_os_pages(size_t pages, int numa_node, mi_msecs_t max_msecs, size_t* pages_reserved, size_t* psize, mi_memid_t* memid) {
+  *memid = _mi_memid_none();
+  if (psize != NULL) *psize = 0;
+  if (pages_reserved != NULL) *pages_reserved = 0;
+  size_t size = 0;
+  uint8_t* start = mi_os_claim_huge_pages(pages, &size);
+  if (start == NULL) return NULL; // or 32-bit systems
+
+  // Allocate one page at the time but try to place them contiguously
+  // We allocate one page at the time to be able to abort if it takes too long
+  // or to at least allocate as many as available on the system.
+  mi_msecs_t start_t = _mi_clock_start();
+  size_t page = 0;
+  bool all_zero = true;
+  while (page < pages) {
+    // allocate a page
+    bool is_zero = false;
+    void* addr = start + (page * MI_HUGE_OS_PAGE_SIZE);
+    void* p = NULL;
+    int err = _mi_prim_alloc_huge_os_pages(addr, MI_HUGE_OS_PAGE_SIZE, numa_node, &is_zero, &p);
+    if (!is_zero) { all_zero = false;  }
+    if (err != 0) {
+      _mi_warning_message("unable to allocate huge OS page (error: %d (0x%x), address: %p, size: %zx bytes)\n", err, err, addr, MI_HUGE_OS_PAGE_SIZE);
+      break;
+    }
+
+    // Did we succeed at a contiguous address?
+    if (p != addr) {
+      // no success, issue a warning and break
+      if (p != NULL) {
+	_mi_warning_message("could not allocate contiguous huge OS page %zu at %p\n", page, addr);
+	mi_os_prim_free(p, MI_HUGE_OS_PAGE_SIZE, true, &_mi_stats_main);
+      }
+      break;
+    }
+
+    // success, record it
+    page++;  // increase before timeout check (see issue #711)
+    _mi_stat_increase(&_mi_stats_main.committed, MI_HUGE_OS_PAGE_SIZE);
+    _mi_stat_increase(&_mi_stats_main.reserved, MI_HUGE_OS_PAGE_SIZE);
+
+    // check for timeout
+    if (max_msecs > 0) {
+      mi_msecs_t elapsed = _mi_clock_end(start_t);
+      if (page >= 1) {
+	mi_msecs_t estimate = ((elapsed / (page+1)) * pages);
+	if (estimate > 2*max_msecs) { // seems like we are going to timeout, break
+	  elapsed = max_msecs + 1;
+	}
+      }
+      if (elapsed > max_msecs) {
+	_mi_warning_message("huge OS page allocation timed out (after allocating %zu page(s))\n", page);
+	break;
+      }
+    }
+  }
+  mi_assert_internal(page*MI_HUGE_OS_PAGE_SIZE <= size);
+  if (pages_reserved != NULL) { *pages_reserved = page; }
+  if (psize != NULL) { *psize = page * MI_HUGE_OS_PAGE_SIZE; }
+  if (page != 0) {
+    mi_assert(start != NULL);
+    *memid = _mi_memid_create_os(true /* is committed */, all_zero, true /* is_large */);
+    memid->memkind = MI_MEM_OS_HUGE;
+    mi_assert(memid->is_pinned);
+    #ifdef MI_TRACK_ASAN
+    if (all_zero) { mi_track_mem_defined(start,size); }
+    #endif
+  }
+  return (page == 0 ? NULL : start);
+}
+
+// free every huge page in a range individually (as we allocated per page)
+// note: needed with VirtualAlloc but could potentially be done in one go on mmap'd systems.
+static void mi_os_free_huge_os_pages(void* p, size_t size, mi_stats_t* stats) {
+  if (p==NULL || size==0) return;
+  uint8_t* base = (uint8_t*)p;
+  while (size >= MI_HUGE_OS_PAGE_SIZE) {
+    mi_os_prim_free(base, MI_HUGE_OS_PAGE_SIZE, true, stats);
+    size -= MI_HUGE_OS_PAGE_SIZE;
+    base += MI_HUGE_OS_PAGE_SIZE;
+  }
+}
+
+/* ----------------------------------------------------------------------------
+Support NUMA aware allocation
+-----------------------------------------------------------------------------*/
+
+_Atomic(size_t)  _mi_numa_node_count; // = 0   // cache the node count
+
+size_t _mi_os_numa_node_count_get(void) {
+  size_t count = mi_atomic_load_acquire(&_mi_numa_node_count);
+  if (count <= 0) {
+    long ncount = mi_option_get(mi_option_use_numa_nodes); // given explicitly?
+    if (ncount > 0) {
+      count = (size_t)ncount;
+    }
+    else {
+      count = _mi_prim_numa_node_count(); // or detect dynamically
+      if (count == 0) count = 1;
+    }
+    mi_atomic_store_release(&_mi_numa_node_count, count); // save it
+    _mi_verbose_message("using %zd numa regions\n", count);
+  }
+  return count;
+}
+
+int _mi_os_numa_node_get(mi_os_tld_t* tld) {
+  MI_UNUSED(tld);
+  size_t numa_count = _mi_os_numa_node_count();
+  if (numa_count<=1) return 0; // optimize on single numa node systems: always node 0
+  // never more than the node count and >= 0
+  size_t numa_node = _mi_prim_numa_node();
+  if (numa_node >= numa_count) { numa_node = numa_node % numa_count; }
+  return (int)numa_node;
+}
diff --git a/compat/mimalloc/page-queue.c b/compat/mimalloc/page-queue.c
new file mode 100644
index 00000000000000..5619a81f9917fe
--- /dev/null
+++ b/compat/mimalloc/page-queue.c
@@ -0,0 +1,332 @@
+/*----------------------------------------------------------------------------
+Copyright (c) 2018-2020, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+
+/* -----------------------------------------------------------
+  Definition of page queues for each block size
+----------------------------------------------------------- */
+
+#ifndef MI_IN_PAGE_C
+#error "this file should be included from 'page.c'"
+#endif
+
+/* -----------------------------------------------------------
+  Minimal alignment in machine words (i.e. `sizeof(void*)`)
+----------------------------------------------------------- */
+
+#if (MI_MAX_ALIGN_SIZE > 4*MI_INTPTR_SIZE)
+  #error "define alignment for more than 4x word size for this platform"
+#elif (MI_MAX_ALIGN_SIZE > 2*MI_INTPTR_SIZE)
+  #define MI_ALIGN4W   // 4 machine words minimal alignment
+#elif (MI_MAX_ALIGN_SIZE > MI_INTPTR_SIZE)
+  #define MI_ALIGN2W   // 2 machine words minimal alignment
+#else
+  // ok, default alignment is 1 word
+#endif
+
+
+/* -----------------------------------------------------------
+  Queue query
+----------------------------------------------------------- */
+
+
+static inline bool mi_page_queue_is_huge(const mi_page_queue_t* pq) {
+  return (pq->block_size == (MI_MEDIUM_OBJ_SIZE_MAX+sizeof(uintptr_t)));
+}
+
+static inline bool mi_page_queue_is_full(const mi_page_queue_t* pq) {
+  return (pq->block_size == (MI_MEDIUM_OBJ_SIZE_MAX+(2*sizeof(uintptr_t))));
+}
+
+static inline bool mi_page_queue_is_special(const mi_page_queue_t* pq) {
+  return (pq->block_size > MI_MEDIUM_OBJ_SIZE_MAX);
+}
+
+/* -----------------------------------------------------------
+  Bins
+----------------------------------------------------------- */
+
+// Return the bin for a given field size.
+// Returns MI_BIN_HUGE if the size is too large.
+// We use `wsize` for the size in "machine word sizes",
+// i.e. byte size == `wsize*sizeof(void*)`.
+static inline uint8_t mi_bin(size_t size) {
+  size_t wsize = _mi_wsize_from_size(size);
+  uint8_t bin;
+  if (wsize <= 1) {
+    bin = 1;
+  }
+  #if defined(MI_ALIGN4W)
+  else if (wsize <= 4) {
+    bin = (uint8_t)((wsize+1)&~1); // round to double word sizes
+  }
+  #elif defined(MI_ALIGN2W)
+  else if (wsize <= 8) {
+    bin = (uint8_t)((wsize+1)&~1); // round to double word sizes
+  }
+  #else
+  else if (wsize <= 8) {
+    bin = (uint8_t)wsize;
+  }
+  #endif
+  else if (wsize > MI_MEDIUM_OBJ_WSIZE_MAX) {
+    bin = MI_BIN_HUGE;
+  }
+  else {
+    #if defined(MI_ALIGN4W)
+    if (wsize <= 16) { wsize = (wsize+3)&~3; } // round to 4x word sizes
+    #endif
+    wsize--;
+    // find the highest bit
+    uint8_t b = (uint8_t)mi_bsr(wsize);  // note: wsize != 0
+    // and use the top 3 bits to determine the bin (~12.5% worst internal fragmentation).
+    // - adjust with 3 because we use do not round the first 8 sizes
+    //   which each get an exact bin
+    bin = ((b << 2) + (uint8_t)((wsize >> (b - 2)) & 0x03)) - 3;
+    mi_assert_internal(bin < MI_BIN_HUGE);
+  }
+  mi_assert_internal(bin > 0 && bin <= MI_BIN_HUGE);
+  return bin;
+}
+
+
+
+/* -----------------------------------------------------------
+  Queue of pages with free blocks
+----------------------------------------------------------- */
+
+uint8_t _mi_bin(size_t size) {
+  return mi_bin(size);
+}
+
+size_t _mi_bin_size(uint8_t bin) {
+  return _mi_heap_empty.pages[bin].block_size;
+}
+
+// Good size for allocation
+size_t mi_good_size(size_t size) mi_attr_noexcept {
+  if (size <= MI_MEDIUM_OBJ_SIZE_MAX) {
+    return _mi_bin_size(mi_bin(size));
+  }
+  else {
+    return _mi_align_up(size,_mi_os_page_size());
+  }
+}
+
+#if (MI_DEBUG>1)
+static bool mi_page_queue_contains(mi_page_queue_t* queue, const mi_page_t* page) {
+  mi_assert_internal(page != NULL);
+  mi_page_t* list = queue->first;
+  while (list != NULL) {
+    mi_assert_internal(list->next == NULL || list->next->prev == list);
+    mi_assert_internal(list->prev == NULL || list->prev->next == list);
+    if (list == page) break;
+    list = list->next;
+  }
+  return (list == page);
+}
+
+#endif
+
+#if (MI_DEBUG>1)
+static bool mi_heap_contains_queue(const mi_heap_t* heap, const mi_page_queue_t* pq) {
+  return (pq >= &heap->pages[0] && pq <= &heap->pages[MI_BIN_FULL]);
+}
+#endif
+
+static mi_page_queue_t* mi_page_queue_of(const mi_page_t* page) {
+  uint8_t bin = (mi_page_is_in_full(page) ? MI_BIN_FULL : mi_bin(page->xblock_size));
+  mi_heap_t* heap = mi_page_heap(page);
+  mi_assert_internal(heap != NULL && bin <= MI_BIN_FULL);
+  mi_page_queue_t* pq = &heap->pages[bin];
+  mi_assert_internal(bin >= MI_BIN_HUGE || page->xblock_size == pq->block_size);
+  mi_assert_expensive(mi_page_queue_contains(pq, page));
+  return pq;
+}
+
+static mi_page_queue_t* mi_heap_page_queue_of(mi_heap_t* heap, const mi_page_t* page) {
+  uint8_t bin = (mi_page_is_in_full(page) ? MI_BIN_FULL : mi_bin(page->xblock_size));
+  mi_assert_internal(bin <= MI_BIN_FULL);
+  mi_page_queue_t* pq = &heap->pages[bin];
+  mi_assert_internal(mi_page_is_in_full(page) || page->xblock_size == pq->block_size);
+  return pq;
+}
+
+// The current small page array is for efficiency and for each
+// small size (up to 256) it points directly to the page for that
+// size without having to compute the bin. This means when the
+// current free page queue is updated for a small bin, we need to update a
+// range of entries in `_mi_page_small_free`.
+static inline void mi_heap_queue_first_update(mi_heap_t* heap, const mi_page_queue_t* pq) {
+  mi_assert_internal(mi_heap_contains_queue(heap,pq));
+  size_t size = pq->block_size;
+  if (size > MI_SMALL_SIZE_MAX) return;
+
+  mi_page_t* page = pq->first;
+  if (pq->first == NULL) page = (mi_page_t*)&_mi_page_empty;
+
+  // find index in the right direct page array
+  size_t start;
+  size_t idx = _mi_wsize_from_size(size);
+  mi_page_t** pages_free = heap->pages_free_direct;
+
+  if (pages_free[idx] == page) return;  // already set
+
+  // find start slot
+  if (idx<=1) {
+    start = 0;
+  }
+  else {
+    // find previous size; due to minimal alignment upto 3 previous bins may need to be skipped
+    uint8_t bin = mi_bin(size);
+    const mi_page_queue_t* prev = pq - 1;
+    while( bin == mi_bin(prev->block_size) && prev > &heap->pages[0]) {
+      prev--;
+    }
+    start = 1 + _mi_wsize_from_size(prev->block_size);
+    if (start > idx) start = idx;
+  }
+
+  // set size range to the right page
+  mi_assert(start <= idx);
+  for (size_t sz = start; sz <= idx; sz++) {
+    pages_free[sz] = page;
+  }
+}
+
+/*
+static bool mi_page_queue_is_empty(mi_page_queue_t* queue) {
+  return (queue->first == NULL);
+}
+*/
+
+static void mi_page_queue_remove(mi_page_queue_t* queue, mi_page_t* page) {
+  mi_assert_internal(page != NULL);
+  mi_assert_expensive(mi_page_queue_contains(queue, page));
+  mi_assert_internal(page->xblock_size == queue->block_size || (page->xblock_size > MI_MEDIUM_OBJ_SIZE_MAX && mi_page_queue_is_huge(queue))  || (mi_page_is_in_full(page) && mi_page_queue_is_full(queue)));
+  mi_heap_t* heap = mi_page_heap(page);
+
+  if (page->prev != NULL) page->prev->next = page->next;
+  if (page->next != NULL) page->next->prev = page->prev;
+  if (page == queue->last)  queue->last = page->prev;
+  if (page == queue->first) {
+    queue->first = page->next;
+    // update first
+    mi_assert_internal(mi_heap_contains_queue(heap, queue));
+    mi_heap_queue_first_update(heap,queue);
+  }
+  heap->page_count--;
+  page->next = NULL;
+  page->prev = NULL;
+  // mi_atomic_store_ptr_release(mi_atomic_cast(void*, &page->heap), NULL);
+  mi_page_set_in_full(page,false);
+}
+
+
+static void mi_page_queue_push(mi_heap_t* heap, mi_page_queue_t* queue, mi_page_t* page) {
+  mi_assert_internal(mi_page_heap(page) == heap);
+  mi_assert_internal(!mi_page_queue_contains(queue, page));
+  #if MI_HUGE_PAGE_ABANDON
+  mi_assert_internal(_mi_page_segment(page)->kind != MI_SEGMENT_HUGE);
+  #endif
+  mi_assert_internal(page->xblock_size == queue->block_size ||
+		      (page->xblock_size > MI_MEDIUM_OBJ_SIZE_MAX) ||
+			(mi_page_is_in_full(page) && mi_page_queue_is_full(queue)));
+
+  mi_page_set_in_full(page, mi_page_queue_is_full(queue));
+  // mi_atomic_store_ptr_release(mi_atomic_cast(void*, &page->heap), heap);
+  page->next = queue->first;
+  page->prev = NULL;
+  if (queue->first != NULL) {
+    mi_assert_internal(queue->first->prev == NULL);
+    queue->first->prev = page;
+    queue->first = page;
+  }
+  else {
+    queue->first = queue->last = page;
+  }
+
+  // update direct
+  mi_heap_queue_first_update(heap, queue);
+  heap->page_count++;
+}
+
+
+static void mi_page_queue_enqueue_from(mi_page_queue_t* to, mi_page_queue_t* from, mi_page_t* page) {
+  mi_assert_internal(page != NULL);
+  mi_assert_expensive(mi_page_queue_contains(from, page));
+  mi_assert_expensive(!mi_page_queue_contains(to, page));
+
+  mi_assert_internal((page->xblock_size == to->block_size && page->xblock_size == from->block_size) ||
+		     (page->xblock_size == to->block_size && mi_page_queue_is_full(from)) ||
+		     (page->xblock_size == from->block_size && mi_page_queue_is_full(to)) ||
+		     (page->xblock_size > MI_LARGE_OBJ_SIZE_MAX && mi_page_queue_is_huge(to)) ||
+		     (page->xblock_size > MI_LARGE_OBJ_SIZE_MAX && mi_page_queue_is_full(to)));
+
+  mi_heap_t* heap = mi_page_heap(page);
+  if (page->prev != NULL) page->prev->next = page->next;
+  if (page->next != NULL) page->next->prev = page->prev;
+  if (page == from->last)  from->last = page->prev;
+  if (page == from->first) {
+    from->first = page->next;
+    // update first
+    mi_assert_internal(mi_heap_contains_queue(heap, from));
+    mi_heap_queue_first_update(heap, from);
+  }
+
+  page->prev = to->last;
+  page->next = NULL;
+  if (to->last != NULL) {
+    mi_assert_internal(heap == mi_page_heap(to->last));
+    to->last->next = page;
+    to->last = page;
+  }
+  else {
+    to->first = page;
+    to->last = page;
+    mi_heap_queue_first_update(heap, to);
+  }
+
+  mi_page_set_in_full(page, mi_page_queue_is_full(to));
+}
+
+// Only called from `mi_heap_absorb`.
+size_t _mi_page_queue_append(mi_heap_t* heap, mi_page_queue_t* pq, mi_page_queue_t* append) {
+  mi_assert_internal(mi_heap_contains_queue(heap,pq));
+  mi_assert_internal(pq->block_size == append->block_size);
+
+  if (append->first==NULL) return 0;
+
+  // set append pages to new heap and count
+  size_t count = 0;
+  for (mi_page_t* page = append->first; page != NULL; page = page->next) {
+    // inline `mi_page_set_heap` to avoid wrong assertion during absorption;
+    // in this case it is ok to be delayed freeing since both "to" and "from" heap are still alive.
+    mi_atomic_store_release(&page->xheap, (uintptr_t)heap);
+    // set the flag to delayed free (not overriding NEVER_DELAYED_FREE) which has as a
+    // side effect that it spins until any DELAYED_FREEING is finished. This ensures
+    // that after appending only the new heap will be used for delayed free operations.
+    _mi_page_use_delayed_free(page, MI_USE_DELAYED_FREE, false);
+    count++;
+  }
+
+  if (pq->last==NULL) {
+    // take over afresh
+    mi_assert_internal(pq->first==NULL);
+    pq->first = append->first;
+    pq->last = append->last;
+    mi_heap_queue_first_update(heap, pq);
+  }
+  else {
+    // append to end
+    mi_assert_internal(pq->last!=NULL);
+    mi_assert_internal(append->first!=NULL);
+    pq->last->next = append->first;
+    append->first->prev = pq->last;
+    pq->last = append->last;
+  }
+  return count;
+}
diff --git a/compat/mimalloc/page.c b/compat/mimalloc/page.c
new file mode 100644
index 00000000000000..211204aa79e59d
--- /dev/null
+++ b/compat/mimalloc/page.c
@@ -0,0 +1,939 @@
+/*----------------------------------------------------------------------------
+Copyright (c) 2018-2020, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+
+/* -----------------------------------------------------------
+  The core of the allocator. Every segment contains
+  pages of a certain block size. The main function
+  exported is `mi_malloc_generic`.
+----------------------------------------------------------- */
+
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "mimalloc/atomic.h"
+
+/* -----------------------------------------------------------
+  Definition of page queues for each block size
+----------------------------------------------------------- */
+
+#define MI_IN_PAGE_C
+#include "page-queue.c"
+#undef MI_IN_PAGE_C
+
+
+/* -----------------------------------------------------------
+  Page helpers
+----------------------------------------------------------- */
+
+// Index a block in a page
+static inline mi_block_t* mi_page_block_at(const mi_page_t* page, void* page_start, size_t block_size, size_t i) {
+  MI_UNUSED(page);
+  mi_assert_internal(page != NULL);
+  mi_assert_internal(i <= page->reserved);
+  return (mi_block_t*)((uint8_t*)page_start + (i * block_size));
+}
+
+static void mi_page_init(mi_heap_t* heap, mi_page_t* page, size_t size, mi_tld_t* tld);
+static void mi_page_extend_free(mi_heap_t* heap, mi_page_t* page, mi_tld_t* tld);
+
+#if (MI_DEBUG>=3)
+static size_t mi_page_list_count(mi_page_t* page, mi_block_t* head) {
+  size_t count = 0;
+  while (head != NULL) {
+    mi_assert_internal(page == _mi_ptr_page(head));
+    count++;
+    head = mi_block_next(page, head);
+  }
+  return count;
+}
+
+/*
+// Start of the page available memory
+static inline uint8_t* mi_page_area(const mi_page_t* page) {
+  return _mi_page_start(_mi_page_segment(page), page, NULL);
+}
+*/
+
+static bool mi_page_list_is_valid(mi_page_t* page, mi_block_t* p) {
+  size_t psize;
+  uint8_t* page_area = _mi_page_start(_mi_page_segment(page), page, &psize);
+  mi_block_t* start = (mi_block_t*)page_area;
+  mi_block_t* end   = (mi_block_t*)(page_area + psize);
+  while(p != NULL) {
+    if (p < start || p >= end) return false;
+    p = mi_block_next(page, p);
+  }
+#if MI_DEBUG>3 // generally too expensive to check this
+  if (page->free_is_zero) {
+    const size_t ubsize = mi_page_usable_block_size(page);
+    for (mi_block_t* block = page->free; block != NULL; block = mi_block_next(page, block)) {
+      mi_assert_expensive(mi_mem_is_zero(block + 1, ubsize - sizeof(mi_block_t)));
+    }
+  }
+#endif
+  return true;
+}
+
+static bool mi_page_is_valid_init(mi_page_t* page) {
+  mi_assert_internal(page->xblock_size > 0);
+  mi_assert_internal(page->used <= page->capacity);
+  mi_assert_internal(page->capacity <= page->reserved);
+
+  mi_segment_t* segment = _mi_page_segment(page);
+  uint8_t* start = _mi_page_start(segment,page,NULL);
+  mi_assert_internal(start == _mi_segment_page_start(segment,page,NULL));
+  //const size_t bsize = mi_page_block_size(page);
+  //mi_assert_internal(start + page->capacity*page->block_size == page->top);
+
+  mi_assert_internal(mi_page_list_is_valid(page,page->free));
+  mi_assert_internal(mi_page_list_is_valid(page,page->local_free));
+
+  #if MI_DEBUG>3 // generally too expensive to check this
+  if (page->free_is_zero) {
+    const size_t ubsize = mi_page_usable_block_size(page);
+    for(mi_block_t* block = page->free; block != NULL; block = mi_block_next(page,block)) {
+      mi_assert_expensive(mi_mem_is_zero(block + 1, ubsize - sizeof(mi_block_t)));
+    }
+  }
+  #endif
+
+  #if !MI_TRACK_ENABLED && !MI_TSAN
+  mi_block_t* tfree = mi_page_thread_free(page);
+  mi_assert_internal(mi_page_list_is_valid(page, tfree));
+  //size_t tfree_count = mi_page_list_count(page, tfree);
+  //mi_assert_internal(tfree_count <= page->thread_freed + 1);
+  #endif
+
+  size_t free_count = mi_page_list_count(page, page->free) + mi_page_list_count(page, page->local_free);
+  mi_assert_internal(page->used + free_count == page->capacity);
+
+  return true;
+}
+
+extern bool _mi_process_is_initialized;             // has mi_process_init been called?
+
+bool _mi_page_is_valid(mi_page_t* page) {
+  mi_assert_internal(mi_page_is_valid_init(page));
+  #if MI_SECURE
+  mi_assert_internal(page->keys[0] != 0);
+  #endif
+  if (mi_page_heap(page)!=NULL) {
+    mi_segment_t* segment = _mi_page_segment(page);
+
+    mi_assert_internal(!_mi_process_is_initialized || segment->thread_id==0 || segment->thread_id == mi_page_heap(page)->thread_id);
+    #if MI_HUGE_PAGE_ABANDON
+    if (segment->kind != MI_SEGMENT_HUGE)
+    #endif
+    {
+      mi_page_queue_t* pq = mi_page_queue_of(page);
+      mi_assert_internal(mi_page_queue_contains(pq, page));
+      mi_assert_internal(pq->block_size==mi_page_block_size(page) || mi_page_block_size(page) > MI_MEDIUM_OBJ_SIZE_MAX || mi_page_is_in_full(page));
+      mi_assert_internal(mi_heap_contains_queue(mi_page_heap(page),pq));
+    }
+  }
+  return true;
+}
+#endif
+
+void _mi_page_use_delayed_free(mi_page_t* page, mi_delayed_t delay, bool override_never) {
+  while (!_mi_page_try_use_delayed_free(page, delay, override_never)) {
+    mi_atomic_yield();
+  }
+}
+
+bool _mi_page_try_use_delayed_free(mi_page_t* page, mi_delayed_t delay, bool override_never) {
+  mi_thread_free_t tfreex;
+  mi_delayed_t     old_delay;
+  mi_thread_free_t tfree;
+  size_t yield_count = 0;
+  do {
+    tfree = mi_atomic_load_acquire(&page->xthread_free); // note: must acquire as we can break/repeat this loop and not do a CAS;
+    tfreex = mi_tf_set_delayed(tfree, delay);
+    old_delay = mi_tf_delayed(tfree);
+    if mi_unlikely(old_delay == MI_DELAYED_FREEING) {
+      if (yield_count >= 4) return false;  // give up after 4 tries
+      yield_count++;
+      mi_atomic_yield(); // delay until outstanding MI_DELAYED_FREEING are done.
+      // tfree = mi_tf_set_delayed(tfree, MI_NO_DELAYED_FREE); // will cause CAS to busy fail
+    }
+    else if (delay == old_delay) {
+      break; // avoid atomic operation if already equal
+    }
+    else if (!override_never && old_delay == MI_NEVER_DELAYED_FREE) {
+      break; // leave never-delayed flag set
+    }
+  } while ((old_delay == MI_DELAYED_FREEING) ||
+	   !mi_atomic_cas_weak_release(&page->xthread_free, &tfree, tfreex));
+
+  return true; // success
+}
+
+/* -----------------------------------------------------------
+  Page collect the `local_free` and `thread_free` lists
+----------------------------------------------------------- */
+
+// Collect the local `thread_free` list using an atomic exchange.
+// Note: The exchange must be done atomically as this is used right after
+// moving to the full list in `mi_page_collect_ex` and we need to
+// ensure that there was no race where the page became unfull just before the move.
+static void _mi_page_thread_free_collect(mi_page_t* page)
+{
+  mi_block_t* head;
+  mi_thread_free_t tfreex;
+  mi_thread_free_t tfree = mi_atomic_load_relaxed(&page->xthread_free);
+  do {
+    head = mi_tf_block(tfree);
+    tfreex = mi_tf_set_block(tfree,NULL);
+  } while (!mi_atomic_cas_weak_acq_rel(&page->xthread_free, &tfree, tfreex));
+
+  // return if the list is empty
+  if (head == NULL) return;
+
+  // find the tail -- also to get a proper count (without data races)
+  uint32_t max_count = page->capacity; // cannot collect more than capacity
+  uint32_t count = 1;
+  mi_block_t* tail = head;
+  mi_block_t* next;
+  while ((next = mi_block_next(page,tail)) != NULL && count <= max_count) {
+    count++;
+    tail = next;
+  }
+  // if `count > max_count` there was a memory corruption (possibly infinite list due to double multi-threaded free)
+  if (count > max_count) {
+    _mi_error_message(EFAULT, "corrupted thread-free list\n");
+    return; // the thread-free items cannot be freed
+  }
+
+  // and append the current local free list
+  mi_block_set_next(page,tail, page->local_free);
+  page->local_free = head;
+
+  // update counts now
+  page->used -= count;
+}
+
+void _mi_page_free_collect(mi_page_t* page, bool force) {
+  mi_assert_internal(page!=NULL);
+
+  // collect the thread free list
+  if (force || mi_page_thread_free(page) != NULL) {  // quick test to avoid an atomic operation
+    _mi_page_thread_free_collect(page);
+  }
+
+  // and the local free list
+  if (page->local_free != NULL) {
+    if mi_likely(page->free == NULL) {
+      // usual case
+      page->free = page->local_free;
+      page->local_free = NULL;
+      page->free_is_zero = false;
+    }
+    else if (force) {
+      // append -- only on shutdown (force) as this is a linear operation
+      mi_block_t* tail = page->local_free;
+      mi_block_t* next;
+      while ((next = mi_block_next(page, tail)) != NULL) {
+	tail = next;
+      }
+      mi_block_set_next(page, tail, page->free);
+      page->free = page->local_free;
+      page->local_free = NULL;
+      page->free_is_zero = false;
+    }
+  }
+
+  mi_assert_internal(!force || page->local_free == NULL);
+}
+
+
+
+/* -----------------------------------------------------------
+  Page fresh and retire
+----------------------------------------------------------- */
+
+// called from segments when reclaiming abandoned pages
+void _mi_page_reclaim(mi_heap_t* heap, mi_page_t* page) {
+  mi_assert_expensive(mi_page_is_valid_init(page));
+
+  mi_assert_internal(mi_page_heap(page) == heap);
+  mi_assert_internal(mi_page_thread_free_flag(page) != MI_NEVER_DELAYED_FREE);
+  #if MI_HUGE_PAGE_ABANDON
+  mi_assert_internal(_mi_page_segment(page)->kind != MI_SEGMENT_HUGE);
+  #endif
+
+  // TODO: push on full queue immediately if it is full?
+  mi_page_queue_t* pq = mi_page_queue(heap, mi_page_block_size(page));
+  mi_page_queue_push(heap, pq, page);
+  mi_assert_expensive(_mi_page_is_valid(page));
+}
+
+// allocate a fresh page from a segment
+static mi_page_t* mi_page_fresh_alloc(mi_heap_t* heap, mi_page_queue_t* pq, size_t block_size, size_t page_alignment) {
+  #if !MI_HUGE_PAGE_ABANDON
+  mi_assert_internal(pq != NULL);
+  mi_assert_internal(mi_heap_contains_queue(heap, pq));
+  mi_assert_internal(page_alignment > 0 || block_size > MI_MEDIUM_OBJ_SIZE_MAX || block_size == pq->block_size);
+  #endif
+  mi_page_t* page = _mi_segment_page_alloc(heap, block_size, page_alignment, &heap->tld->segments, &heap->tld->os);
+  if (page == NULL) {
+    // this may be out-of-memory, or an abandoned page was reclaimed (and in our queue)
+    return NULL;
+  }
+  mi_assert_internal(page_alignment >0 || block_size > MI_MEDIUM_OBJ_SIZE_MAX || _mi_page_segment(page)->kind != MI_SEGMENT_HUGE);
+  mi_assert_internal(pq!=NULL || page->xblock_size != 0);
+  mi_assert_internal(pq!=NULL || mi_page_block_size(page) >= block_size);
+  // a fresh page was found, initialize it
+  const size_t full_block_size = ((pq == NULL || mi_page_queue_is_huge(pq)) ? mi_page_block_size(page) : block_size); // see also: mi_segment_huge_page_alloc
+  mi_assert_internal(full_block_size >= block_size);
+  mi_page_init(heap, page, full_block_size, heap->tld);
+  mi_heap_stat_increase(heap, pages, 1);
+  if (pq != NULL) { mi_page_queue_push(heap, pq, page); }
+  mi_assert_expensive(_mi_page_is_valid(page));
+  return page;
+}
+
+// Get a fresh page to use
+static mi_page_t* mi_page_fresh(mi_heap_t* heap, mi_page_queue_t* pq) {
+  mi_assert_internal(mi_heap_contains_queue(heap, pq));
+  mi_page_t* page = mi_page_fresh_alloc(heap, pq, pq->block_size, 0);
+  if (page==NULL) return NULL;
+  mi_assert_internal(pq->block_size==mi_page_block_size(page));
+  mi_assert_internal(pq==mi_page_queue(heap, mi_page_block_size(page)));
+  return page;
+}
+
+/* -----------------------------------------------------------
+   Do any delayed frees
+   (put there by other threads if they deallocated in a full page)
+----------------------------------------------------------- */
+void _mi_heap_delayed_free_all(mi_heap_t* heap) {
+  while (!_mi_heap_delayed_free_partial(heap)) {
+    mi_atomic_yield();
+  }
+}
+
+// returns true if all delayed frees were processed
+bool _mi_heap_delayed_free_partial(mi_heap_t* heap) {
+  // take over the list (note: no atomic exchange since it is often NULL)
+  mi_block_t* block = mi_atomic_load_ptr_relaxed(mi_block_t, &heap->thread_delayed_free);
+  while (block != NULL && !mi_atomic_cas_ptr_weak_acq_rel(mi_block_t, &heap->thread_delayed_free, &block, NULL)) { /* nothing */ };
+  bool all_freed = true;
+
+  // and free them all
+  while(block != NULL) {
+    mi_block_t* next = mi_block_nextx(heap,block, heap->keys);
+    // use internal free instead of regular one to keep stats etc correct
+    if (!_mi_free_delayed_block(block)) {
+      // we might already start delayed freeing while another thread has not yet
+      // reset the delayed_freeing flag; in that case delay it further by reinserting the current block
+      // into the delayed free list
+      all_freed = false;
+      mi_block_t* dfree = mi_atomic_load_ptr_relaxed(mi_block_t, &heap->thread_delayed_free);
+      do {
+	mi_block_set_nextx(heap, block, dfree, heap->keys);
+      } while (!mi_atomic_cas_ptr_weak_release(mi_block_t,&heap->thread_delayed_free, &dfree, block));
+    }
+    block = next;
+  }
+  return all_freed;
+}
+
+/* -----------------------------------------------------------
+  Unfull, abandon, free and retire
+----------------------------------------------------------- */
+
+// Move a page from the full list back to a regular list
+void _mi_page_unfull(mi_page_t* page) {
+  mi_assert_internal(page != NULL);
+  mi_assert_expensive(_mi_page_is_valid(page));
+  mi_assert_internal(mi_page_is_in_full(page));
+  if (!mi_page_is_in_full(page)) return;
+
+  mi_heap_t* heap = mi_page_heap(page);
+  mi_page_queue_t* pqfull = &heap->pages[MI_BIN_FULL];
+  mi_page_set_in_full(page, false); // to get the right queue
+  mi_page_queue_t* pq = mi_heap_page_queue_of(heap, page);
+  mi_page_set_in_full(page, true);
+  mi_page_queue_enqueue_from(pq, pqfull, page);
+}
+
+static void mi_page_to_full(mi_page_t* page, mi_page_queue_t* pq) {
+  mi_assert_internal(pq == mi_page_queue_of(page));
+  mi_assert_internal(!mi_page_immediate_available(page));
+  mi_assert_internal(!mi_page_is_in_full(page));
+
+  if (mi_page_is_in_full(page)) return;
+  mi_page_queue_enqueue_from(&mi_page_heap(page)->pages[MI_BIN_FULL], pq, page);
+  _mi_page_free_collect(page,false);  // try to collect right away in case another thread freed just before MI_USE_DELAYED_FREE was set
+}
+
+
+// Abandon a page with used blocks at the end of a thread.
+// Note: only call if it is ensured that no references exist from
+// the `page->heap->thread_delayed_free` into this page.
+// Currently only called through `mi_heap_collect_ex` which ensures this.
+void _mi_page_abandon(mi_page_t* page, mi_page_queue_t* pq) {
+  mi_assert_internal(page != NULL);
+  mi_assert_expensive(_mi_page_is_valid(page));
+  mi_assert_internal(pq == mi_page_queue_of(page));
+  mi_assert_internal(mi_page_heap(page) != NULL);
+
+  mi_heap_t* pheap = mi_page_heap(page);
+
+  // remove from our page list
+  mi_segments_tld_t* segments_tld = &pheap->tld->segments;
+  mi_page_queue_remove(pq, page);
+
+  // page is no longer associated with our heap
+  mi_assert_internal(mi_page_thread_free_flag(page)==MI_NEVER_DELAYED_FREE);
+  mi_page_set_heap(page, NULL);
+
+#if (MI_DEBUG>1) && !MI_TRACK_ENABLED
+  // check there are no references left..
+  for (mi_block_t* block = (mi_block_t*)pheap->thread_delayed_free; block != NULL; block = mi_block_nextx(pheap, block, pheap->keys)) {
+    mi_assert_internal(_mi_ptr_page(block) != page);
+  }
+#endif
+
+  // and abandon it
+  mi_assert_internal(mi_page_heap(page) == NULL);
+  _mi_segment_page_abandon(page,segments_tld);
+}
+
+
+// Free a page with no more free blocks
+void _mi_page_free(mi_page_t* page, mi_page_queue_t* pq, bool force) {
+  mi_assert_internal(page != NULL);
+  mi_assert_expensive(_mi_page_is_valid(page));
+  mi_assert_internal(pq == mi_page_queue_of(page));
+  mi_assert_internal(mi_page_all_free(page));
+  mi_assert_internal(mi_page_thread_free_flag(page)!=MI_DELAYED_FREEING);
+
+  // no more aligned blocks in here
+  mi_page_set_has_aligned(page, false);
+
+  mi_heap_t* heap = mi_page_heap(page);
+
+  // remove from the page list
+  // (no need to do _mi_heap_delayed_free first as all blocks are already free)
+  mi_segments_tld_t* segments_tld = &heap->tld->segments;
+  mi_page_queue_remove(pq, page);
+
+  // and free it
+  mi_page_set_heap(page,NULL);
+  _mi_segment_page_free(page, force, segments_tld);
+}
+
+// Retire parameters
+#define MI_MAX_RETIRE_SIZE    (MI_MEDIUM_OBJ_SIZE_MAX)
+#define MI_RETIRE_CYCLES      (16)
+
+// Retire a page with no more used blocks
+// Important to not retire too quickly though as new
+// allocations might coming.
+// Note: called from `mi_free` and benchmarks often
+// trigger this due to freeing everything and then
+// allocating again so careful when changing this.
+void _mi_page_retire(mi_page_t* page) mi_attr_noexcept {
+  mi_assert_internal(page != NULL);
+  mi_assert_expensive(_mi_page_is_valid(page));
+  mi_assert_internal(mi_page_all_free(page));
+
+  mi_page_set_has_aligned(page, false);
+
+  // don't retire too often..
+  // (or we end up retiring and re-allocating most of the time)
+  // NOTE: refine this more: we should not retire if this
+  // is the only page left with free blocks. It is not clear
+  // how to check this efficiently though...
+  // for now, we don't retire if it is the only page left of this size class.
+  mi_page_queue_t* pq = mi_page_queue_of(page);
+  if mi_likely(page->xblock_size <= MI_MAX_RETIRE_SIZE && !mi_page_queue_is_special(pq)) {  // not too large && not full or huge queue?
+    if (pq->last==page && pq->first==page) { // the only page in the queue?
+      mi_stat_counter_increase(_mi_stats_main.page_no_retire,1);
+      page->retire_expire = 1 + (page->xblock_size <= MI_SMALL_OBJ_SIZE_MAX ? MI_RETIRE_CYCLES : MI_RETIRE_CYCLES/4);
+      mi_heap_t* heap = mi_page_heap(page);
+      mi_assert_internal(pq >= heap->pages);
+      const size_t index = pq - heap->pages;
+      mi_assert_internal(index < MI_BIN_FULL && index < MI_BIN_HUGE);
+      if (index < heap->page_retired_min) heap->page_retired_min = index;
+      if (index > heap->page_retired_max) heap->page_retired_max = index;
+      mi_assert_internal(mi_page_all_free(page));
+      return; // dont't free after all
+    }
+  }
+  _mi_page_free(page, pq, false);
+}
+
+// free retired pages: we don't need to look at the entire queues
+// since we only retire pages that are at the head position in a queue.
+void _mi_heap_collect_retired(mi_heap_t* heap, bool force) {
+  size_t min = MI_BIN_FULL;
+  size_t max = 0;
+  for(size_t bin = heap->page_retired_min; bin <= heap->page_retired_max; bin++) {
+    mi_page_queue_t* pq   = &heap->pages[bin];
+    mi_page_t*       page = pq->first;
+    if (page != NULL && page->retire_expire != 0) {
+      if (mi_page_all_free(page)) {
+	page->retire_expire--;
+	if (force || page->retire_expire == 0) {
+	  _mi_page_free(pq->first, pq, force);
+	}
+	else {
+	  // keep retired, update min/max
+	  if (bin < min) min = bin;
+	  if (bin > max) max = bin;
+	}
+      }
+      else {
+	page->retire_expire = 0;
+      }
+    }
+  }
+  heap->page_retired_min = min;
+  heap->page_retired_max = max;
+}
+
+
+/* -----------------------------------------------------------
+  Initialize the initial free list in a page.
+  In secure mode we initialize a randomized list by
+  alternating between slices.
+----------------------------------------------------------- */
+
+#define MI_MAX_SLICE_SHIFT  (6)   // at most 64 slices
+#define MI_MAX_SLICES       (1UL << MI_MAX_SLICE_SHIFT)
+#define MI_MIN_SLICES       (2)
+
+static void mi_page_free_list_extend_secure(mi_heap_t* const heap, mi_page_t* const page, const size_t bsize, const size_t extend, mi_stats_t* const stats) {
+  MI_UNUSED(stats);
+  #if (MI_SECURE<=2)
+  mi_assert_internal(page->free == NULL);
+  mi_assert_internal(page->local_free == NULL);
+  #endif
+  mi_assert_internal(page->capacity + extend <= page->reserved);
+  mi_assert_internal(bsize == mi_page_block_size(page));
+  void* const page_area = _mi_page_start(_mi_page_segment(page), page, NULL);
+
+  // initialize a randomized free list
+  // set up `slice_count` slices to alternate between
+  size_t shift = MI_MAX_SLICE_SHIFT;
+  while ((extend >> shift) == 0) {
+    shift--;
+  }
+  const size_t slice_count = (size_t)1U << shift;
+  const size_t slice_extend = extend / slice_count;
+  mi_assert_internal(slice_extend >= 1);
+  mi_block_t* blocks[MI_MAX_SLICES];   // current start of the slice
+  size_t      counts[MI_MAX_SLICES];   // available objects in the slice
+  for (size_t i = 0; i < slice_count; i++) {
+    blocks[i] = mi_page_block_at(page, page_area, bsize, page->capacity + i*slice_extend);
+    counts[i] = slice_extend;
+  }
+  counts[slice_count-1] += (extend % slice_count);  // final slice holds the modulus too (todo: distribute evenly?)
+
+  // and initialize the free list by randomly threading through them
+  // set up first element
+  const uintptr_t r = _mi_heap_random_next(heap);
+  size_t current = r % slice_count;
+  counts[current]--;
+  mi_block_t* const free_start = blocks[current];
+  // and iterate through the rest; use `random_shuffle` for performance
+  uintptr_t rnd = _mi_random_shuffle(r|1); // ensure not 0
+  for (size_t i = 1; i < extend; i++) {
+    // call random_shuffle only every INTPTR_SIZE rounds
+    const size_t round = i%MI_INTPTR_SIZE;
+    if (round == 0) rnd = _mi_random_shuffle(rnd);
+    // select a random next slice index
+    size_t next = ((rnd >> 8*round) & (slice_count-1));
+    while (counts[next]==0) {                            // ensure it still has space
+      next++;
+      if (next==slice_count) next = 0;
+    }
+    // and link the current block to it
+    counts[next]--;
+    mi_block_t* const block = blocks[current];
+    blocks[current] = (mi_block_t*)((uint8_t*)block + bsize);  // bump to the following block
+    mi_block_set_next(page, block, blocks[next]);   // and set next; note: we may have `current == next`
+    current = next;
+  }
+  // prepend to the free list (usually NULL)
+  mi_block_set_next(page, blocks[current], page->free);  // end of the list
+  page->free = free_start;
+}
+
+static mi_decl_noinline void mi_page_free_list_extend( mi_page_t* const page, const size_t bsize, const size_t extend, mi_stats_t* const stats)
+{
+  MI_UNUSED(stats);
+  #if (MI_SECURE <= 2)
+  mi_assert_internal(page->free == NULL);
+  mi_assert_internal(page->local_free == NULL);
+  #endif
+  mi_assert_internal(page->capacity + extend <= page->reserved);
+  mi_assert_internal(bsize == mi_page_block_size(page));
+  void* const page_area = _mi_page_start(_mi_page_segment(page), page, NULL );
+
+  mi_block_t* const start = mi_page_block_at(page, page_area, bsize, page->capacity);
+
+  // initialize a sequential free list
+  mi_block_t* const last = mi_page_block_at(page, page_area, bsize, page->capacity + extend - 1);
+  mi_block_t* block = start;
+  while(block <= last) {
+    mi_block_t* next = (mi_block_t*)((uint8_t*)block + bsize);
+    mi_block_set_next(page,block,next);
+    block = next;
+  }
+  // prepend to free list (usually `NULL`)
+  mi_block_set_next(page, last, page->free);
+  page->free = start;
+}
+
+/* -----------------------------------------------------------
+  Page initialize and extend the capacity
+----------------------------------------------------------- */
+
+#define MI_MAX_EXTEND_SIZE    (4*1024)      // heuristic, one OS page seems to work well.
+#if (MI_SECURE>0)
+#define MI_MIN_EXTEND         (8*MI_SECURE) // extend at least by this many
+#else
+#define MI_MIN_EXTEND         (4)
+#endif
+
+// Extend the capacity (up to reserved) by initializing a free list
+// We do at most `MI_MAX_EXTEND` to avoid touching too much memory
+// Note: we also experimented with "bump" allocation on the first
+// allocations but this did not speed up any benchmark (due to an
+// extra test in malloc? or cache effects?)
+static void mi_page_extend_free(mi_heap_t* heap, mi_page_t* page, mi_tld_t* tld) {
+  MI_UNUSED(tld);
+  mi_assert_expensive(mi_page_is_valid_init(page));
+  #if (MI_SECURE<=2)
+  mi_assert(page->free == NULL);
+  mi_assert(page->local_free == NULL);
+  if (page->free != NULL) return;
+  #endif
+  if (page->capacity >= page->reserved) return;
+
+  size_t page_size;
+  _mi_page_start(_mi_page_segment(page), page, &page_size);
+  mi_stat_counter_increase(tld->stats.pages_extended, 1);
+
+  // calculate the extend count
+  const size_t bsize = (page->xblock_size < MI_HUGE_BLOCK_SIZE ? page->xblock_size : page_size);
+  size_t extend = page->reserved - page->capacity;
+  mi_assert_internal(extend > 0);
+
+  size_t max_extend = (bsize >= MI_MAX_EXTEND_SIZE ? MI_MIN_EXTEND : MI_MAX_EXTEND_SIZE/(uint32_t)bsize);
+  if (max_extend < MI_MIN_EXTEND) { max_extend = MI_MIN_EXTEND; }
+  mi_assert_internal(max_extend > 0);
+
+  if (extend > max_extend) {
+    // ensure we don't touch memory beyond the page to reduce page commit.
+    // the `lean` benchmark tests this. Going from 1 to 8 increases rss by 50%.
+    extend = max_extend;
+  }
+
+  mi_assert_internal(extend > 0 && extend + page->capacity <= page->reserved);
+  mi_assert_internal(extend < (1UL<<16));
+
+  // and append the extend the free list
+  if (extend < MI_MIN_SLICES || MI_SECURE==0) { //!mi_option_is_enabled(mi_option_secure)) {
+    mi_page_free_list_extend(page, bsize, extend, &tld->stats );
+  }
+  else {
+    mi_page_free_list_extend_secure(heap, page, bsize, extend, &tld->stats);
+  }
+  // enable the new free list
+  page->capacity += (uint16_t)extend;
+  mi_stat_increase(tld->stats.page_committed, extend * bsize);
+  mi_assert_expensive(mi_page_is_valid_init(page));
+}
+
+// Initialize a fresh page
+static void mi_page_init(mi_heap_t* heap, mi_page_t* page, size_t block_size, mi_tld_t* tld) {
+  mi_assert(page != NULL);
+  mi_segment_t* segment = _mi_page_segment(page);
+  mi_assert(segment != NULL);
+  mi_assert_internal(block_size > 0);
+  // set fields
+  mi_page_set_heap(page, heap);
+  page->xblock_size = (block_size < MI_HUGE_BLOCK_SIZE ? (uint32_t)block_size : MI_HUGE_BLOCK_SIZE); // initialize before _mi_segment_page_start
+  size_t page_size;
+  const void* page_start = _mi_segment_page_start(segment, page, &page_size);
+  MI_UNUSED(page_start);
+  mi_track_mem_noaccess(page_start,page_size);
+  mi_assert_internal(mi_page_block_size(page) <= page_size);
+  mi_assert_internal(page_size <= page->slice_count*MI_SEGMENT_SLICE_SIZE);
+  mi_assert_internal(page_size / block_size < (1L<<16));
+  page->reserved = (uint16_t)(page_size / block_size);
+  mi_assert_internal(page->reserved > 0);
+  #if (MI_PADDING || MI_ENCODE_FREELIST)
+  page->keys[0] = _mi_heap_random_next(heap);
+  page->keys[1] = _mi_heap_random_next(heap);
+  #endif
+  page->free_is_zero = page->is_zero_init;
+  #if MI_DEBUG>2
+  if (page->is_zero_init) {
+    mi_track_mem_defined(page_start, page_size);
+    mi_assert_expensive(mi_mem_is_zero(page_start, page_size));
+  }
+  #endif
+
+  mi_assert_internal(page->is_committed);
+  mi_assert_internal(page->capacity == 0);
+  mi_assert_internal(page->free == NULL);
+  mi_assert_internal(page->used == 0);
+  mi_assert_internal(page->xthread_free == 0);
+  mi_assert_internal(page->next == NULL);
+  mi_assert_internal(page->prev == NULL);
+  mi_assert_internal(page->retire_expire == 0);
+  mi_assert_internal(!mi_page_has_aligned(page));
+  #if (MI_PADDING || MI_ENCODE_FREELIST)
+  mi_assert_internal(page->keys[0] != 0);
+  mi_assert_internal(page->keys[1] != 0);
+  #endif
+  mi_assert_expensive(mi_page_is_valid_init(page));
+
+  // initialize an initial free list
+  mi_page_extend_free(heap,page,tld);
+  mi_assert(mi_page_immediate_available(page));
+}
+
+
+/* -----------------------------------------------------------
+  Find pages with free blocks
+-------------------------------------------------------------*/
+
+// Find a page with free blocks of `page->block_size`.
+static mi_page_t* mi_page_queue_find_free_ex(mi_heap_t* heap, mi_page_queue_t* pq, bool first_try)
+{
+  // search through the pages in "next fit" order
+  #if MI_STAT
+  size_t count = 0;
+  #endif
+  mi_page_t* page = pq->first;
+  while (page != NULL)
+  {
+    mi_page_t* next = page->next; // remember next
+    #if MI_STAT
+    count++;
+    #endif
+
+    // 0. collect freed blocks by us and other threads
+    _mi_page_free_collect(page, false);
+
+    // 1. if the page contains free blocks, we are done
+    if (mi_page_immediate_available(page)) {
+      break;  // pick this one
+    }
+
+    // 2. Try to extend
+    if (page->capacity < page->reserved) {
+      mi_page_extend_free(heap, page, heap->tld);
+      mi_assert_internal(mi_page_immediate_available(page));
+      break;
+    }
+
+    // 3. If the page is completely full, move it to the `mi_pages_full`
+    // queue so we don't visit long-lived pages too often.
+    mi_assert_internal(!mi_page_is_in_full(page) && !mi_page_immediate_available(page));
+    mi_page_to_full(page, pq);
+
+    page = next;
+  } // for each page
+
+  mi_heap_stat_counter_increase(heap, searches, count);
+
+  if (page == NULL) {
+    _mi_heap_collect_retired(heap, false); // perhaps make a page available?
+    page = mi_page_fresh(heap, pq);
+    if (page == NULL && first_try) {
+      // out-of-memory _or_ an abandoned page with free blocks was reclaimed, try once again
+      page = mi_page_queue_find_free_ex(heap, pq, false);
+    }
+  }
+  else {
+    mi_assert(pq->first == page);
+    page->retire_expire = 0;
+  }
+  mi_assert_internal(page == NULL || mi_page_immediate_available(page));
+  return page;
+}
+
+
+
+// Find a page with free blocks of `size`.
+static inline mi_page_t* mi_find_free_page(mi_heap_t* heap, size_t size) {
+  mi_page_queue_t* pq = mi_page_queue(heap,size);
+  mi_page_t* page = pq->first;
+  if (page != NULL) {
+   #if (MI_SECURE>=3) // in secure mode, we extend half the time to increase randomness
+    if (page->capacity < page->reserved && ((_mi_heap_random_next(heap) & 1) == 1)) {
+      mi_page_extend_free(heap, page, heap->tld);
+      mi_assert_internal(mi_page_immediate_available(page));
+    }
+    else
+   #endif
+    {
+      _mi_page_free_collect(page,false);
+    }
+
+    if (mi_page_immediate_available(page)) {
+      page->retire_expire = 0;
+      return page; // fast path
+    }
+  }
+  return mi_page_queue_find_free_ex(heap, pq, true);
+}
+
+
+/* -----------------------------------------------------------
+  Users can register a deferred free function called
+  when the `free` list is empty. Since the `local_free`
+  is separate this is deterministically called after
+  a certain number of allocations.
+----------------------------------------------------------- */
+
+static mi_deferred_free_fun* volatile deferred_free = NULL;
+static _Atomic(void*) deferred_arg; // = NULL
+
+void _mi_deferred_free(mi_heap_t* heap, bool force) {
+  heap->tld->heartbeat++;
+  if (deferred_free != NULL && !heap->tld->recurse) {
+    heap->tld->recurse = true;
+    deferred_free(force, heap->tld->heartbeat, mi_atomic_load_ptr_relaxed(void,&deferred_arg));
+    heap->tld->recurse = false;
+  }
+}
+
+void mi_register_deferred_free(mi_deferred_free_fun* fn, void* arg) mi_attr_noexcept {
+  deferred_free = fn;
+  mi_atomic_store_ptr_release(void,&deferred_arg, arg);
+}
+
+
+/* -----------------------------------------------------------
+  General allocation
+----------------------------------------------------------- */
+
+// Large and huge page allocation.
+// Huge pages are allocated directly without being in a queue.
+// Because huge pages contain just one block, and the segment contains
+// just that page, we always treat them as abandoned and any thread
+// that frees the block can free the whole page and segment directly.
+// Huge pages are also use if the requested alignment is very large (> MI_ALIGNMENT_MAX).
+static mi_page_t* mi_large_huge_page_alloc(mi_heap_t* heap, size_t size, size_t page_alignment) {
+  size_t block_size = _mi_os_good_alloc_size(size);
+  mi_assert_internal(mi_bin(block_size) == MI_BIN_HUGE || page_alignment > 0);
+  bool is_huge = (block_size > MI_LARGE_OBJ_SIZE_MAX || page_alignment > 0);
+  #if MI_HUGE_PAGE_ABANDON
+  mi_page_queue_t* pq = (is_huge ? NULL : mi_page_queue(heap, block_size));
+  #else
+  mi_page_queue_t* pq = mi_page_queue(heap, is_huge ? MI_HUGE_BLOCK_SIZE : block_size); // not block_size as that can be low if the page_alignment > 0
+  mi_assert_internal(!is_huge || mi_page_queue_is_huge(pq));
+  #endif
+  mi_page_t* page = mi_page_fresh_alloc(heap, pq, block_size, page_alignment);
+  if (page != NULL) {
+    mi_assert_internal(mi_page_immediate_available(page));
+
+    if (is_huge) {
+      mi_assert_internal(_mi_page_segment(page)->kind == MI_SEGMENT_HUGE);
+      mi_assert_internal(_mi_page_segment(page)->used==1);
+      #if MI_HUGE_PAGE_ABANDON
+      mi_assert_internal(_mi_page_segment(page)->thread_id==0); // abandoned, not in the huge queue
+      mi_page_set_heap(page, NULL);
+      #endif
+    }
+    else {
+      mi_assert_internal(_mi_page_segment(page)->kind != MI_SEGMENT_HUGE);
+    }
+
+    const size_t bsize = mi_page_usable_block_size(page);  // note: not `mi_page_block_size` to account for padding
+    if (bsize <= MI_LARGE_OBJ_SIZE_MAX) {
+      mi_heap_stat_increase(heap, large, bsize);
+      mi_heap_stat_counter_increase(heap, large_count, 1);
+    }
+    else {
+      mi_heap_stat_increase(heap, huge, bsize);
+      mi_heap_stat_counter_increase(heap, huge_count, 1);
+    }
+  }
+  return page;
+}
+
+
+// Allocate a page
+// Note: in debug mode the size includes MI_PADDING_SIZE and might have overflowed.
+static mi_page_t* mi_find_page(mi_heap_t* heap, size_t size, size_t huge_alignment) mi_attr_noexcept {
+  // huge allocation?
+  const size_t req_size = size - MI_PADDING_SIZE;  // correct for padding_size in case of an overflow on `size`
+  if mi_unlikely(req_size > (MI_MEDIUM_OBJ_SIZE_MAX - MI_PADDING_SIZE) || huge_alignment > 0) {
+    if mi_unlikely(req_size > PTRDIFF_MAX) {  // we don't allocate more than PTRDIFF_MAX (see <https://sourceware.org/ml/libc-announce/2019/msg00001.html>)
+      _mi_error_message(EOVERFLOW, "allocation request is too large (%zu bytes)\n", req_size);
+      return NULL;
+    }
+    else {
+      return mi_large_huge_page_alloc(heap,size,huge_alignment);
+    }
+  }
+  else {
+    // otherwise find a page with free blocks in our size segregated queues
+    #if MI_PADDING
+    mi_assert_internal(size >= MI_PADDING_SIZE);
+    #endif
+    return mi_find_free_page(heap, size);
+  }
+}
+
+// Generic allocation routine if the fast path (`alloc.c:mi_page_malloc`) does not succeed.
+// Note: in debug mode the size includes MI_PADDING_SIZE and might have overflowed.
+// The `huge_alignment` is normally 0 but is set to a multiple of MI_SEGMENT_SIZE for
+// very large requested alignments in which case we use a huge segment.
+void* _mi_malloc_generic(mi_heap_t* heap, size_t size, bool zero, size_t huge_alignment) mi_attr_noexcept
+{
+  mi_assert_internal(heap != NULL);
+
+  // initialize if necessary
+  if mi_unlikely(!mi_heap_is_initialized(heap)) {
+    heap = mi_heap_get_default(); // calls mi_thread_init
+    if mi_unlikely(!mi_heap_is_initialized(heap)) { return NULL; }
+  }
+  mi_assert_internal(mi_heap_is_initialized(heap));
+
+  // call potential deferred free routines
+  _mi_deferred_free(heap, false);
+
+  // free delayed frees from other threads (but skip contended ones)
+  _mi_heap_delayed_free_partial(heap);
+
+  // find (or allocate) a page of the right size
+  mi_page_t* page = mi_find_page(heap, size, huge_alignment);
+  if mi_unlikely(page == NULL) { // first time out of memory, try to collect and retry the allocation once more
+    mi_heap_collect(heap, true /* force */);
+    page = mi_find_page(heap, size, huge_alignment);
+  }
+
+  if mi_unlikely(page == NULL) { // out of memory
+    const size_t req_size = size - MI_PADDING_SIZE;  // correct for padding_size in case of an overflow on `size`
+    _mi_error_message(ENOMEM, "unable to allocate memory (%zu bytes)\n", req_size);
+    return NULL;
+  }
+
+  mi_assert_internal(mi_page_immediate_available(page));
+  mi_assert_internal(mi_page_block_size(page) >= size);
+
+  // and try again, this time succeeding! (i.e. this should never recurse through _mi_page_malloc)
+  if mi_unlikely(zero && page->xblock_size == 0) {
+    // note: we cannot call _mi_page_malloc with zeroing for huge blocks; we zero it afterwards in that case.
+    void* p = _mi_page_malloc(heap, page, size, false);
+    mi_assert_internal(p != NULL);
+    _mi_memzero_aligned(p, mi_page_usable_block_size(page));
+    return p;
+  }
+  else {
+    return _mi_page_malloc(heap, page, size, zero);
+  }
+}
diff --git a/compat/mimalloc/prim/windows/prim.c b/compat/mimalloc/prim/windows/prim.c
new file mode 100644
index 00000000000000..d060833c5b644d
--- /dev/null
+++ b/compat/mimalloc/prim/windows/prim.c
@@ -0,0 +1,622 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2023, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+
+// This file is included in `src/prim/prim.c`
+
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "mimalloc/atomic.h"
+#include "mimalloc/prim.h"
+#include <stdio.h>   // fputs, stderr
+
+
+//---------------------------------------------
+// Dynamically bind Windows API points for portability
+//---------------------------------------------
+
+// We use VirtualAlloc2 for aligned allocation, but it is only supported on Windows 10 and Windows Server 2016.
+// So, we need to look it up dynamically to run on older systems. (use __stdcall for 32-bit compatibility)
+// NtAllocateVirtualAllocEx is used for huge OS page allocation (1GiB)
+// We define a minimal MEM_EXTENDED_PARAMETER ourselves in order to be able to compile with older SDK's.
+typedef enum MI_MEM_EXTENDED_PARAMETER_TYPE_E {
+  MiMemExtendedParameterInvalidType = 0,
+  MiMemExtendedParameterAddressRequirements,
+  MiMemExtendedParameterNumaNode,
+  MiMemExtendedParameterPartitionHandle,
+  MiMemExtendedParameterUserPhysicalHandle,
+  MiMemExtendedParameterAttributeFlags,
+  MiMemExtendedParameterMax
+} MI_MEM_EXTENDED_PARAMETER_TYPE;
+
+typedef struct DECLSPEC_ALIGN(8) MI_MEM_EXTENDED_PARAMETER_S {
+  struct { DWORD64 Type : 8; DWORD64 Reserved : 56; } Type;
+  union  { DWORD64 ULong64; PVOID Pointer; SIZE_T Size; HANDLE Handle; DWORD ULong; } Arg;
+} MI_MEM_EXTENDED_PARAMETER;
+
+typedef struct MI_MEM_ADDRESS_REQUIREMENTS_S {
+  PVOID  LowestStartingAddress;
+  PVOID  HighestEndingAddress;
+  SIZE_T Alignment;
+} MI_MEM_ADDRESS_REQUIREMENTS;
+
+#define MI_MEM_EXTENDED_PARAMETER_NONPAGED_HUGE   0x00000010
+
+#include <winternl.h>
+typedef PVOID    (__stdcall *PVirtualAlloc2)(HANDLE, PVOID, SIZE_T, ULONG, ULONG, MI_MEM_EXTENDED_PARAMETER*, ULONG);
+typedef NTSTATUS (__stdcall *PNtAllocateVirtualMemoryEx)(HANDLE, PVOID*, SIZE_T*, ULONG, ULONG, MI_MEM_EXTENDED_PARAMETER*, ULONG);
+static PVirtualAlloc2 pVirtualAlloc2 = NULL;
+static PNtAllocateVirtualMemoryEx pNtAllocateVirtualMemoryEx = NULL;
+
+// Similarly, GetNumaProcesorNodeEx is only supported since Windows 7
+typedef struct MI_PROCESSOR_NUMBER_S { WORD Group; BYTE Number; BYTE Reserved; } MI_PROCESSOR_NUMBER;
+
+typedef VOID (__stdcall *PGetCurrentProcessorNumberEx)(MI_PROCESSOR_NUMBER* ProcNumber);
+typedef BOOL (__stdcall *PGetNumaProcessorNodeEx)(MI_PROCESSOR_NUMBER* Processor, PUSHORT NodeNumber);
+typedef BOOL (__stdcall* PGetNumaNodeProcessorMaskEx)(USHORT Node, PGROUP_AFFINITY ProcessorMask);
+typedef BOOL (__stdcall *PGetNumaProcessorNode)(UCHAR Processor, PUCHAR NodeNumber);
+static PGetCurrentProcessorNumberEx pGetCurrentProcessorNumberEx = NULL;
+static PGetNumaProcessorNodeEx      pGetNumaProcessorNodeEx = NULL;
+static PGetNumaNodeProcessorMaskEx  pGetNumaNodeProcessorMaskEx = NULL;
+static PGetNumaProcessorNode        pGetNumaProcessorNode = NULL;
+
+//---------------------------------------------
+// Enable large page support dynamically (if possible)
+//---------------------------------------------
+
+static bool win_enable_large_os_pages(size_t* large_page_size)
+{
+  static bool large_initialized = false;
+  if (large_initialized) return (_mi_os_large_page_size() > 0);
+  large_initialized = true;
+
+  // Try to see if large OS pages are supported
+  // To use large pages on Windows, we first need access permission
+  // Set "Lock pages in memory" permission in the group policy editor
+  // <https://devblogs.microsoft.com/oldnewthing/20110128-00/?p=11643>
+  unsigned long err = 0;
+  HANDLE token = NULL;
+  BOOL ok = OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &token);
+  if (ok) {
+    TOKEN_PRIVILEGES tp;
+    ok = LookupPrivilegeValue(NULL, TEXT("SeLockMemoryPrivilege"), &tp.Privileges[0].Luid);
+    if (ok) {
+      tp.PrivilegeCount = 1;
+      tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
+      ok = AdjustTokenPrivileges(token, FALSE, &tp, 0, (PTOKEN_PRIVILEGES)NULL, 0);
+      if (ok) {
+	err = GetLastError();
+	ok = (err == ERROR_SUCCESS);
+	if (ok && large_page_size != NULL) {
+	  *large_page_size = GetLargePageMinimum();
+	}
+      }
+    }
+    CloseHandle(token);
+  }
+  if (!ok) {
+    if (err == 0) err = GetLastError();
+    _mi_warning_message("cannot enable large OS page support, error %lu\n", err);
+  }
+  return (ok!=0);
+}
+
+
+//---------------------------------------------
+// Initialize
+//---------------------------------------------
+
+void _mi_prim_mem_init( mi_os_mem_config_t* config )
+{
+  config->has_overcommit = false;
+  config->must_free_whole = true;
+  config->has_virtual_reserve = true;
+  // get the page size
+  SYSTEM_INFO si;
+  GetSystemInfo(&si);
+  if (si.dwPageSize > 0) { config->page_size = si.dwPageSize; }
+  if (si.dwAllocationGranularity > 0) { config->alloc_granularity = si.dwAllocationGranularity; }
+  // get the VirtualAlloc2 function
+  HINSTANCE  hDll;
+  hDll = LoadLibrary(TEXT("kernelbase.dll"));
+  if (hDll != NULL) {
+    // use VirtualAlloc2FromApp if possible as it is available to Windows store apps
+    pVirtualAlloc2 = (PVirtualAlloc2)(void (*)(void))GetProcAddress(hDll, "VirtualAlloc2FromApp");
+    if (pVirtualAlloc2==NULL) pVirtualAlloc2 = (PVirtualAlloc2)(void (*)(void))GetProcAddress(hDll, "VirtualAlloc2");
+    FreeLibrary(hDll);
+  }
+  // NtAllocateVirtualMemoryEx is used for huge page allocation
+  hDll = LoadLibrary(TEXT("ntdll.dll"));
+  if (hDll != NULL) {
+    pNtAllocateVirtualMemoryEx = (PNtAllocateVirtualMemoryEx)(void (*)(void))GetProcAddress(hDll, "NtAllocateVirtualMemoryEx");
+    FreeLibrary(hDll);
+  }
+  // Try to use Win7+ numa API
+  hDll = LoadLibrary(TEXT("kernel32.dll"));
+  if (hDll != NULL) {
+    pGetCurrentProcessorNumberEx = (PGetCurrentProcessorNumberEx)(void (*)(void))GetProcAddress(hDll, "GetCurrentProcessorNumberEx");
+    pGetNumaProcessorNodeEx = (PGetNumaProcessorNodeEx)(void (*)(void))GetProcAddress(hDll, "GetNumaProcessorNodeEx");
+    pGetNumaNodeProcessorMaskEx = (PGetNumaNodeProcessorMaskEx)(void (*)(void))GetProcAddress(hDll, "GetNumaNodeProcessorMaskEx");
+    pGetNumaProcessorNode = (PGetNumaProcessorNode)(void (*)(void))GetProcAddress(hDll, "GetNumaProcessorNode");
+    FreeLibrary(hDll);
+  }
+  if (mi_option_is_enabled(mi_option_allow_large_os_pages) || mi_option_is_enabled(mi_option_reserve_huge_os_pages)) {
+    win_enable_large_os_pages(&config->large_page_size);
+  }
+}
+
+
+//---------------------------------------------
+// Free
+//---------------------------------------------
+
+int _mi_prim_free(void* addr, size_t size ) {
+  MI_UNUSED(size);
+  DWORD errcode = 0;
+  bool err = (VirtualFree(addr, 0, MEM_RELEASE) == 0);
+  if (err) { errcode = GetLastError(); }
+  if (errcode == ERROR_INVALID_ADDRESS) {
+    // In mi_os_mem_alloc_aligned the fallback path may have returned a pointer inside
+    // the memory region returned by VirtualAlloc; in that case we need to free using
+    // the start of the region.
+    MEMORY_BASIC_INFORMATION info = { 0 };
+    VirtualQuery(addr, &info, sizeof(info));
+    if (info.AllocationBase < addr && ((uint8_t*)addr - (uint8_t*)info.AllocationBase) < (ptrdiff_t)MI_SEGMENT_SIZE) {
+      errcode = 0;
+      err = (VirtualFree(info.AllocationBase, 0, MEM_RELEASE) == 0);
+      if (err) { errcode = GetLastError(); }
+    }
+  }
+  return (int)errcode;
+}
+
+
+//---------------------------------------------
+// VirtualAlloc
+//---------------------------------------------
+
+static void* win_virtual_alloc_prim(void* addr, size_t size, size_t try_alignment, DWORD flags) {
+  #if (MI_INTPTR_SIZE >= 8)
+  // on 64-bit systems, try to use the virtual address area after 2TiB for 4MiB aligned allocations
+  if (addr == NULL) {
+    void* hint = _mi_os_get_aligned_hint(try_alignment,size);
+    if (hint != NULL) {
+      void* p = VirtualAlloc(hint, size, flags, PAGE_READWRITE);
+      if (p != NULL) return p;
+      _mi_verbose_message("warning: unable to allocate hinted aligned OS memory (%zu bytes, error code: 0x%x, address: %p, alignment: %zu, flags: 0x%x)\n", size, GetLastError(), hint, try_alignment, flags);
+      // fall through on error
+    }
+  }
+  #endif
+  // on modern Windows try use VirtualAlloc2 for aligned allocation
+  if (try_alignment > 1 && (try_alignment % _mi_os_page_size()) == 0 && pVirtualAlloc2 != NULL) {
+    MI_MEM_ADDRESS_REQUIREMENTS reqs = { 0, 0, 0 };
+    reqs.Alignment = try_alignment;
+    MI_MEM_EXTENDED_PARAMETER param = { {0, 0}, {0} };
+    param.Type.Type = MiMemExtendedParameterAddressRequirements;
+    param.Arg.Pointer = &reqs;
+    void* p = (*pVirtualAlloc2)(GetCurrentProcess(), addr, size, flags, PAGE_READWRITE, &param, 1);
+    if (p != NULL) return p;
+    _mi_warning_message("unable to allocate aligned OS memory (%zu bytes, error code: 0x%x, address: %p, alignment: %zu, flags: 0x%x)\n", size, GetLastError(), addr, try_alignment, flags);
+    // fall through on error
+  }
+  // last resort
+  return VirtualAlloc(addr, size, flags, PAGE_READWRITE);
+}
+
+static void* win_virtual_alloc(void* addr, size_t size, size_t try_alignment, DWORD flags, bool large_only, bool allow_large, bool* is_large) {
+  mi_assert_internal(!(large_only && !allow_large));
+  static _Atomic(size_t) large_page_try_ok; // = 0;
+  void* p = NULL;
+  // Try to allocate large OS pages (2MiB) if allowed or required.
+  if ((large_only || _mi_os_use_large_page(size, try_alignment))
+      && allow_large && (flags&MEM_COMMIT)!=0 && (flags&MEM_RESERVE)!=0) {
+    size_t try_ok = mi_atomic_load_acquire(&large_page_try_ok);
+    if (!large_only && try_ok > 0) {
+      // if a large page allocation fails, it seems the calls to VirtualAlloc get very expensive.
+      // therefore, once a large page allocation failed, we don't try again for `large_page_try_ok` times.
+      mi_atomic_cas_strong_acq_rel(&large_page_try_ok, &try_ok, try_ok - 1);
+    }
+    else {
+      // large OS pages must always reserve and commit.
+      *is_large = true;
+      p = win_virtual_alloc_prim(addr, size, try_alignment, flags | MEM_LARGE_PAGES);
+      if (large_only) return p;
+      // fall back to non-large page allocation on error (`p == NULL`).
+      if (p == NULL) {
+	mi_atomic_store_release(&large_page_try_ok,10UL);  // on error, don't try again for the next N allocations
+      }
+    }
+  }
+  // Fall back to regular page allocation
+  if (p == NULL) {
+    *is_large = ((flags&MEM_LARGE_PAGES) != 0);
+    p = win_virtual_alloc_prim(addr, size, try_alignment, flags);
+  }
+  //if (p == NULL) { _mi_warning_message("unable to allocate OS memory (%zu bytes, error code: 0x%x, address: %p, alignment: %zu, flags: 0x%x, large only: %d, allow large: %d)\n", size, GetLastError(), addr, try_alignment, flags, large_only, allow_large); }
+  return p;
+}
+
+int _mi_prim_alloc(size_t size, size_t try_alignment, bool commit, bool allow_large, bool* is_large, bool* is_zero, void** addr) {
+  mi_assert_internal(size > 0 && (size % _mi_os_page_size()) == 0);
+  mi_assert_internal(commit || !allow_large);
+  mi_assert_internal(try_alignment > 0);
+  *is_zero = true;
+  int flags = MEM_RESERVE;
+  if (commit) { flags |= MEM_COMMIT; }
+  *addr = win_virtual_alloc(NULL, size, try_alignment, flags, false, allow_large, is_large);
+  return (*addr != NULL ? 0 : (int)GetLastError());
+}
+
+
+//---------------------------------------------
+// Commit/Reset/Protect
+//---------------------------------------------
+#ifdef _MSC_VER
+#pragma warning(disable:6250)   // suppress warning calling VirtualFree without MEM_RELEASE (for decommit)
+#endif
+
+int _mi_prim_commit(void* addr, size_t size, bool* is_zero) {
+  *is_zero = false;
+  /*
+  // zero'ing only happens on an initial commit... but checking upfront seems expensive..
+  _MEMORY_BASIC_INFORMATION meminfo; _mi_memzero_var(meminfo);
+  if (VirtualQuery(addr, &meminfo, size) > 0) {
+    if ((meminfo.State & MEM_COMMIT) == 0) {
+      *is_zero = true;
+    }
+  }
+  */
+  // commit
+  void* p = VirtualAlloc(addr, size, MEM_COMMIT, PAGE_READWRITE);
+  if (p == NULL) return (int)GetLastError();
+  return 0;
+}
+
+int _mi_prim_decommit(void* addr, size_t size, bool* needs_recommit) {
+  BOOL ok = VirtualFree(addr, size, MEM_DECOMMIT);
+  *needs_recommit = true;  // for safety, assume always decommitted even in the case of an error.
+  return (ok ? 0 : (int)GetLastError());
+}
+
+int _mi_prim_reset(void* addr, size_t size) {
+  void* p = VirtualAlloc(addr, size, MEM_RESET, PAGE_READWRITE);
+  mi_assert_internal(p == addr);
+  #if 0
+  if (p != NULL) {
+    VirtualUnlock(addr,size); // VirtualUnlock after MEM_RESET removes the memory directly from the working set
+  }
+  #endif
+  return (p != NULL ? 0 : (int)GetLastError());
+}
+
+int _mi_prim_protect(void* addr, size_t size, bool protect) {
+  DWORD oldprotect = 0;
+  BOOL ok = VirtualProtect(addr, size, protect ? PAGE_NOACCESS : PAGE_READWRITE, &oldprotect);
+  return (ok ? 0 : (int)GetLastError());
+}
+
+
+//---------------------------------------------
+// Huge page allocation
+//---------------------------------------------
+
+static void* _mi_prim_alloc_huge_os_pagesx(void* hint_addr, size_t size, int numa_node)
+{
+  const DWORD flags = MEM_LARGE_PAGES | MEM_COMMIT | MEM_RESERVE;
+
+  win_enable_large_os_pages(NULL);
+
+  MI_MEM_EXTENDED_PARAMETER params[3] = { {{0,0},{0}},{{0,0},{0}},{{0,0},{0}} };
+  // on modern Windows try use NtAllocateVirtualMemoryEx for 1GiB huge pages
+  static bool mi_huge_pages_available = true;
+  if (pNtAllocateVirtualMemoryEx != NULL && mi_huge_pages_available) {
+    params[0].Type.Type = MiMemExtendedParameterAttributeFlags;
+    params[0].Arg.ULong64 = MI_MEM_EXTENDED_PARAMETER_NONPAGED_HUGE;
+    ULONG param_count = 1;
+    if (numa_node >= 0) {
+      param_count++;
+      params[1].Type.Type = MiMemExtendedParameterNumaNode;
+      params[1].Arg.ULong = (unsigned)numa_node;
+    }
+    SIZE_T psize = size;
+    void* base = hint_addr;
+    NTSTATUS err = (*pNtAllocateVirtualMemoryEx)(GetCurrentProcess(), &base, &psize, flags, PAGE_READWRITE, params, param_count);
+    if (err == 0 && base != NULL) {
+      return base;
+    }
+    else {
+      // fall back to regular large pages
+      mi_huge_pages_available = false; // don't try further huge pages
+      _mi_warning_message("unable to allocate using huge (1GiB) pages, trying large (2MiB) pages instead (status 0x%lx)\n", err);
+    }
+  }
+  // on modern Windows try use VirtualAlloc2 for numa aware large OS page allocation
+  if (pVirtualAlloc2 != NULL && numa_node >= 0) {
+    params[0].Type.Type = MiMemExtendedParameterNumaNode;
+    params[0].Arg.ULong = (unsigned)numa_node;
+    return (*pVirtualAlloc2)(GetCurrentProcess(), hint_addr, size, flags, PAGE_READWRITE, params, 1);
+  }
+
+  // otherwise use regular virtual alloc on older windows
+  return VirtualAlloc(hint_addr, size, flags, PAGE_READWRITE);
+}
+
+int _mi_prim_alloc_huge_os_pages(void* hint_addr, size_t size, int numa_node, bool* is_zero, void** addr) {
+  *is_zero = true;
+  *addr = _mi_prim_alloc_huge_os_pagesx(hint_addr,size,numa_node);
+  return (*addr != NULL ? 0 : (int)GetLastError());
+}
+
+
+//---------------------------------------------
+// Numa nodes
+//---------------------------------------------
+
+size_t _mi_prim_numa_node(void) {
+  USHORT numa_node = 0;
+  if (pGetCurrentProcessorNumberEx != NULL && pGetNumaProcessorNodeEx != NULL) {
+    // Extended API is supported
+    MI_PROCESSOR_NUMBER pnum;
+    (*pGetCurrentProcessorNumberEx)(&pnum);
+    USHORT nnode = 0;
+    BOOL ok = (*pGetNumaProcessorNodeEx)(&pnum, &nnode);
+    if (ok) { numa_node = nnode; }
+  }
+  else if (pGetNumaProcessorNode != NULL) {
+    // Vista or earlier, use older API that is limited to 64 processors. Issue #277
+    DWORD pnum = GetCurrentProcessorNumber();
+    UCHAR nnode = 0;
+    BOOL ok = pGetNumaProcessorNode((UCHAR)pnum, &nnode);
+    if (ok) { numa_node = nnode; }
+  }
+  return numa_node;
+}
+
+size_t _mi_prim_numa_node_count(void) {
+  ULONG numa_max = 0;
+  GetNumaHighestNodeNumber(&numa_max);
+  // find the highest node number that has actual processors assigned to it. Issue #282
+  while(numa_max > 0) {
+    if (pGetNumaNodeProcessorMaskEx != NULL) {
+      // Extended API is supported
+      GROUP_AFFINITY affinity;
+      if ((*pGetNumaNodeProcessorMaskEx)((USHORT)numa_max, &affinity)) {
+	if (affinity.Mask != 0) break;  // found the maximum non-empty node
+      }
+    }
+    else {
+      // Vista or earlier, use older API that is limited to 64 processors.
+      ULONGLONG mask;
+      if (GetNumaNodeProcessorMask((UCHAR)numa_max, &mask)) {
+	if (mask != 0) break; // found the maximum non-empty node
+      };
+    }
+    // max node was invalid or had no processor assigned, try again
+    numa_max--;
+  }
+  return ((size_t)numa_max + 1);
+}
+
+
+//----------------------------------------------------------------
+// Clock
+//----------------------------------------------------------------
+
+static mi_msecs_t mi_to_msecs(LARGE_INTEGER t) {
+  static LARGE_INTEGER mfreq; // = 0
+  if (mfreq.QuadPart == 0LL) {
+    LARGE_INTEGER f;
+    QueryPerformanceFrequency(&f);
+    mfreq.QuadPart = f.QuadPart/1000LL;
+    if (mfreq.QuadPart == 0) mfreq.QuadPart = 1;
+  }
+  return (mi_msecs_t)(t.QuadPart / mfreq.QuadPart);
+}
+
+mi_msecs_t _mi_prim_clock_now(void) {
+  LARGE_INTEGER t;
+  QueryPerformanceCounter(&t);
+  return mi_to_msecs(t);
+}
+
+
+//----------------------------------------------------------------
+// Process Info
+//----------------------------------------------------------------
+
+#include <windows.h>
+#include <psapi.h>
+
+static mi_msecs_t filetime_msecs(const FILETIME* ftime) {
+  ULARGE_INTEGER i;
+  i.LowPart = ftime->dwLowDateTime;
+  i.HighPart = ftime->dwHighDateTime;
+  mi_msecs_t msecs = (i.QuadPart / 10000); // FILETIME is in 100 nano seconds
+  return msecs;
+}
+
+typedef BOOL (WINAPI *PGetProcessMemoryInfo)(HANDLE, PPROCESS_MEMORY_COUNTERS, DWORD);
+static PGetProcessMemoryInfo pGetProcessMemoryInfo = NULL;
+
+void _mi_prim_process_info(mi_process_info_t* pinfo)
+{
+  FILETIME ct;
+  FILETIME ut;
+  FILETIME st;
+  FILETIME et;
+  GetProcessTimes(GetCurrentProcess(), &ct, &et, &st, &ut);
+  pinfo->utime = filetime_msecs(&ut);
+  pinfo->stime = filetime_msecs(&st);
+
+  // load psapi on demand
+  if (pGetProcessMemoryInfo == NULL) {
+    HINSTANCE hDll = LoadLibrary(TEXT("psapi.dll"));
+    if (hDll != NULL) {
+      pGetProcessMemoryInfo = (PGetProcessMemoryInfo)(void (*)(void))GetProcAddress(hDll, "GetProcessMemoryInfo");
+    }
+  }
+
+  // get process info
+  PROCESS_MEMORY_COUNTERS info;
+  memset(&info, 0, sizeof(info));
+  if (pGetProcessMemoryInfo != NULL) {
+    pGetProcessMemoryInfo(GetCurrentProcess(), &info, sizeof(info));
+  }
+  pinfo->current_rss    = (size_t)info.WorkingSetSize;
+  pinfo->peak_rss       = (size_t)info.PeakWorkingSetSize;
+  pinfo->current_commit = (size_t)info.PagefileUsage;
+  pinfo->peak_commit    = (size_t)info.PeakPagefileUsage;
+  pinfo->page_faults    = (size_t)info.PageFaultCount;
+}
+
+//----------------------------------------------------------------
+// Output
+//----------------------------------------------------------------
+
+void _mi_prim_out_stderr( const char* msg )
+{
+  // on windows with redirection, the C runtime cannot handle locale dependent output
+  // after the main thread closes so we use direct console output.
+  if (!_mi_preloading()) {
+    // _cputs(msg);  // _cputs cannot be used at is aborts if it fails to lock the console
+    static HANDLE hcon = INVALID_HANDLE_VALUE;
+    static bool hconIsConsole;
+    if (hcon == INVALID_HANDLE_VALUE) {
+      CONSOLE_SCREEN_BUFFER_INFO sbi;
+      hcon = GetStdHandle(STD_ERROR_HANDLE);
+      hconIsConsole = ((hcon != INVALID_HANDLE_VALUE) && GetConsoleScreenBufferInfo(hcon, &sbi));
+    }
+    const size_t len = _mi_strlen(msg);
+    if (len > 0 && len < UINT32_MAX) {
+      DWORD written = 0;
+      if (hconIsConsole) {
+	WriteConsoleA(hcon, msg, (DWORD)len, &written, NULL);
+      }
+      else if (hcon != INVALID_HANDLE_VALUE) {
+	// use direct write if stderr was redirected
+	WriteFile(hcon, msg, (DWORD)len, &written, NULL);
+      }
+      else {
+	// finally fall back to fputs after all
+	fputs(msg, stderr);
+      }
+    }
+  }
+}
+
+
+//----------------------------------------------------------------
+// Environment
+//----------------------------------------------------------------
+
+// On Windows use GetEnvironmentVariable instead of getenv to work
+// reliably even when this is invoked before the C runtime is initialized.
+// i.e. when `_mi_preloading() == true`.
+// Note: on windows, environment names are not case sensitive.
+bool _mi_prim_getenv(const char* name, char* result, size_t result_size) {
+  result[0] = 0;
+  size_t len = GetEnvironmentVariableA(name, result, (DWORD)result_size);
+  return (len > 0 && len < result_size);
+}
+
+
+
+//----------------------------------------------------------------
+// Random
+//----------------------------------------------------------------
+
+#if defined(MI_USE_RTLGENRANDOM) // || defined(__cplusplus)
+// We prefer to use BCryptGenRandom instead of (the unofficial) RtlGenRandom but when using
+// dynamic overriding, we observed it can raise an exception when compiled with C++, and
+// sometimes deadlocks when also running under the VS debugger.
+// In contrast, issue #623 implies that on Windows Server 2019 we need to use BCryptGenRandom.
+// To be continued..
+#pragma comment (lib,"advapi32.lib")
+#define RtlGenRandom  SystemFunction036
+mi_decl_externc BOOLEAN NTAPI RtlGenRandom(PVOID RandomBuffer, ULONG RandomBufferLength);
+
+bool _mi_prim_random_buf(void* buf, size_t buf_len) {
+  return (RtlGenRandom(buf, (ULONG)buf_len) != 0);
+}
+
+#else
+
+#ifndef BCRYPT_USE_SYSTEM_PREFERRED_RNG
+#define BCRYPT_USE_SYSTEM_PREFERRED_RNG 0x00000002
+#endif
+
+typedef LONG (NTAPI *PBCryptGenRandom)(HANDLE, PUCHAR, ULONG, ULONG);
+static  PBCryptGenRandom pBCryptGenRandom = NULL;
+
+bool _mi_prim_random_buf(void* buf, size_t buf_len) {
+  if (pBCryptGenRandom == NULL) {
+    HINSTANCE hDll = LoadLibrary(TEXT("bcrypt.dll"));
+    if (hDll != NULL) {
+      pBCryptGenRandom = (PBCryptGenRandom)(void (*)(void))GetProcAddress(hDll, "BCryptGenRandom");
+    }
+    if (pBCryptGenRandom == NULL) return false;
+  }
+  return (pBCryptGenRandom(NULL, (PUCHAR)buf, (ULONG)buf_len, BCRYPT_USE_SYSTEM_PREFERRED_RNG) >= 0);
+}
+
+#endif  // MI_USE_RTLGENRANDOM
+
+//----------------------------------------------------------------
+// Thread init/done
+//----------------------------------------------------------------
+
+#if !defined(MI_SHARED_LIB)
+
+// use thread local storage keys to detect thread ending
+#include <fibersapi.h>
+#if (_WIN32_WINNT < 0x600)  // before Windows Vista
+WINBASEAPI DWORD WINAPI FlsAlloc( _In_opt_ PFLS_CALLBACK_FUNCTION lpCallback );
+WINBASEAPI PVOID WINAPI FlsGetValue( _In_ DWORD dwFlsIndex );
+WINBASEAPI BOOL  WINAPI FlsSetValue( _In_ DWORD dwFlsIndex, _In_opt_ PVOID lpFlsData );
+WINBASEAPI BOOL  WINAPI FlsFree(_In_ DWORD dwFlsIndex);
+#endif
+
+static DWORD mi_fls_key = (DWORD)(-1);
+
+static void NTAPI mi_fls_done(PVOID value) {
+  mi_heap_t* heap = (mi_heap_t*)value;
+  if (heap != NULL) {
+    _mi_thread_done(heap);
+    FlsSetValue(mi_fls_key, NULL);  // prevent recursion as _mi_thread_done may set it back to the main heap, issue #672
+  }
+}
+
+void _mi_prim_thread_init_auto_done(void) {
+  mi_fls_key = FlsAlloc(&mi_fls_done);
+}
+
+void _mi_prim_thread_done_auto_done(void) {
+  // call thread-done on all threads (except the main thread) to prevent
+  // dangling callback pointer if statically linked with a DLL; Issue #208
+  FlsFree(mi_fls_key);
+}
+
+void _mi_prim_thread_associate_default_heap(mi_heap_t* heap) {
+  mi_assert_internal(mi_fls_key != (DWORD)(-1));
+  FlsSetValue(mi_fls_key, heap);
+}
+
+#else
+
+// Dll; nothing to do as in that case thread_done is handled through the DLL_THREAD_DETACH event.
+
+void _mi_prim_thread_init_auto_done(void) {
+}
+
+void _mi_prim_thread_done_auto_done(void) {
+}
+
+void _mi_prim_thread_associate_default_heap(mi_heap_t* heap) {
+  MI_UNUSED(heap);
+}
+
+#endif
diff --git a/compat/mimalloc/random.c b/compat/mimalloc/random.c
new file mode 100644
index 00000000000000..2a18b5aa992dad
--- /dev/null
+++ b/compat/mimalloc/random.c
@@ -0,0 +1,254 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2019-2021, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "mimalloc/prim.h"    // _mi_prim_random_buf
+#include <string.h>       // memset
+
+/* ----------------------------------------------------------------------------
+We use our own PRNG to keep predictable performance of random number generation
+and to avoid implementations that use a lock. We only use the OS provided
+random source to initialize the initial seeds. Since we do not need ultimate
+performance but we do rely on the security (for secret cookies in secure mode)
+we use a cryptographically secure generator (chacha20).
+-----------------------------------------------------------------------------*/
+
+#define MI_CHACHA_ROUNDS (20)   // perhaps use 12 for better performance?
+
+
+/* ----------------------------------------------------------------------------
+Chacha20 implementation as the original algorithm with a 64-bit nonce
+and counter: https://en.wikipedia.org/wiki/Salsa20
+The input matrix has sixteen 32-bit values:
+Position  0 to  3: constant key
+Position  4 to 11: the key
+Position 12 to 13: the counter.
+Position 14 to 15: the nonce.
+
+The implementation uses regular C code which compiles very well on modern compilers.
+(gcc x64 has no register spills, and clang 6+ uses SSE instructions)
+-----------------------------------------------------------------------------*/
+
+static inline uint32_t rotl(uint32_t x, uint32_t shift) {
+  return (x << shift) | (x >> (32 - shift));
+}
+
+static inline void qround(uint32_t x[16], size_t a, size_t b, size_t c, size_t d) {
+  x[a] += x[b]; x[d] = rotl(x[d] ^ x[a], 16);
+  x[c] += x[d]; x[b] = rotl(x[b] ^ x[c], 12);
+  x[a] += x[b]; x[d] = rotl(x[d] ^ x[a], 8);
+  x[c] += x[d]; x[b] = rotl(x[b] ^ x[c], 7);
+}
+
+static void chacha_block(mi_random_ctx_t* ctx)
+{
+  // scramble into `x`
+  uint32_t x[16];
+  for (size_t i = 0; i < 16; i++) {
+    x[i] = ctx->input[i];
+  }
+  for (size_t i = 0; i < MI_CHACHA_ROUNDS; i += 2) {
+    qround(x, 0, 4,  8, 12);
+    qround(x, 1, 5,  9, 13);
+    qround(x, 2, 6, 10, 14);
+    qround(x, 3, 7, 11, 15);
+    qround(x, 0, 5, 10, 15);
+    qround(x, 1, 6, 11, 12);
+    qround(x, 2, 7,  8, 13);
+    qround(x, 3, 4,  9, 14);
+  }
+
+  // add scrambled data to the initial state
+  for (size_t i = 0; i < 16; i++) {
+    ctx->output[i] = x[i] + ctx->input[i];
+  }
+  ctx->output_available = 16;
+
+  // increment the counter for the next round
+  ctx->input[12] += 1;
+  if (ctx->input[12] == 0) {
+    ctx->input[13] += 1;
+    if (ctx->input[13] == 0) {  // and keep increasing into the nonce
+      ctx->input[14] += 1;
+    }
+  }
+}
+
+static uint32_t chacha_next32(mi_random_ctx_t* ctx) {
+  if (ctx->output_available <= 0) {
+    chacha_block(ctx);
+    ctx->output_available = 16; // (assign again to suppress static analysis warning)
+  }
+  const uint32_t x = ctx->output[16 - ctx->output_available];
+  ctx->output[16 - ctx->output_available] = 0; // reset once the data is handed out
+  ctx->output_available--;
+  return x;
+}
+
+static inline uint32_t read32(const uint8_t* p, size_t idx32) {
+  const size_t i = 4*idx32;
+  return ((uint32_t)p[i+0] | (uint32_t)p[i+1] << 8 | (uint32_t)p[i+2] << 16 | (uint32_t)p[i+3] << 24);
+}
+
+static void chacha_init(mi_random_ctx_t* ctx, const uint8_t key[32], uint64_t nonce)
+{
+  // since we only use chacha for randomness (and not encryption) we
+  // do not _need_ to read 32-bit values as little endian but we do anyways
+  // just for being compatible :-)
+  memset(ctx, 0, sizeof(*ctx));
+  for (size_t i = 0; i < 4; i++) {
+    const uint8_t* sigma = (uint8_t*)"expand 32-byte k";
+    ctx->input[i] = read32(sigma,i);
+  }
+  for (size_t i = 0; i < 8; i++) {
+    ctx->input[i + 4] = read32(key,i);
+  }
+  ctx->input[12] = 0;
+  ctx->input[13] = 0;
+  ctx->input[14] = (uint32_t)nonce;
+  ctx->input[15] = (uint32_t)(nonce >> 32);
+}
+
+static void chacha_split(mi_random_ctx_t* ctx, uint64_t nonce, mi_random_ctx_t* ctx_new) {
+  memset(ctx_new, 0, sizeof(*ctx_new));
+  _mi_memcpy(ctx_new->input, ctx->input, sizeof(ctx_new->input));
+  ctx_new->input[12] = 0;
+  ctx_new->input[13] = 0;
+  ctx_new->input[14] = (uint32_t)nonce;
+  ctx_new->input[15] = (uint32_t)(nonce >> 32);
+  mi_assert_internal(ctx->input[14] != ctx_new->input[14] || ctx->input[15] != ctx_new->input[15]); // do not reuse nonces!
+  chacha_block(ctx_new);
+}
+
+
+/* ----------------------------------------------------------------------------
+Random interface
+-----------------------------------------------------------------------------*/
+
+#if MI_DEBUG>1
+static bool mi_random_is_initialized(mi_random_ctx_t* ctx) {
+  return (ctx != NULL && ctx->input[0] != 0);
+}
+#endif
+
+void _mi_random_split(mi_random_ctx_t* ctx, mi_random_ctx_t* ctx_new) {
+  mi_assert_internal(mi_random_is_initialized(ctx));
+  mi_assert_internal(ctx != ctx_new);
+  chacha_split(ctx, (uintptr_t)ctx_new /*nonce*/, ctx_new);
+}
+
+uintptr_t _mi_random_next(mi_random_ctx_t* ctx) {
+  mi_assert_internal(mi_random_is_initialized(ctx));
+  #if MI_INTPTR_SIZE <= 4
+    return chacha_next32(ctx);
+  #elif MI_INTPTR_SIZE == 8
+    return (((uintptr_t)chacha_next32(ctx) << 32) | chacha_next32(ctx));
+  #else
+  # error "define mi_random_next for this platform"
+  #endif
+}
+
+
+/* ----------------------------------------------------------------------------
+To initialize a fresh random context.
+If we cannot get good randomness, we fall back to weak randomness based on a timer and ASLR.
+-----------------------------------------------------------------------------*/
+
+uintptr_t _mi_os_random_weak(uintptr_t extra_seed) {
+  uintptr_t x = (uintptr_t)&_mi_os_random_weak ^ extra_seed; // ASLR makes the address random
+  x ^= _mi_prim_clock_now();
+  // and do a few randomization steps
+  uintptr_t max = ((x ^ (x >> 17)) & 0x0F) + 1;
+  for (uintptr_t i = 0; i < max; i++) {
+    x = _mi_random_shuffle(x);
+  }
+  mi_assert_internal(x != 0);
+  return x;
+}
+
+static void mi_random_init_ex(mi_random_ctx_t* ctx, bool use_weak) {
+  uint8_t key[32];
+  if (use_weak || !_mi_prim_random_buf(key, sizeof(key))) {
+    // if we fail to get random data from the OS, we fall back to a
+    // weak random source based on the current time
+    #if !defined(__wasi__)
+    if (!use_weak) { _mi_warning_message("unable to use secure randomness\n"); }
+    #endif
+    uintptr_t x = _mi_os_random_weak(0);
+    for (size_t i = 0; i < 8; i++) {  // key is eight 32-bit words.
+      x = _mi_random_shuffle(x);
+      ((uint32_t*)key)[i] = (uint32_t)x;
+    }
+    ctx->weak = true;
+  }
+  else {
+    ctx->weak = false;
+  }
+  chacha_init(ctx, key, (uintptr_t)ctx /*nonce*/ );
+}
+
+void _mi_random_init(mi_random_ctx_t* ctx) {
+  mi_random_init_ex(ctx, false);
+}
+
+void _mi_random_init_weak(mi_random_ctx_t * ctx) {
+  mi_random_init_ex(ctx, true);
+}
+
+void _mi_random_reinit_if_weak(mi_random_ctx_t * ctx) {
+  if (ctx->weak) {
+    _mi_random_init(ctx);
+  }
+}
+
+/* --------------------------------------------------------
+test vectors from <https://tools.ietf.org/html/rfc8439>
+----------------------------------------------------------- */
+/*
+static bool array_equals(uint32_t* x, uint32_t* y, size_t n) {
+  for (size_t i = 0; i < n; i++) {
+    if (x[i] != y[i]) return false;
+  }
+  return true;
+}
+static void chacha_test(void)
+{
+  uint32_t x[4] = { 0x11111111, 0x01020304, 0x9b8d6f43, 0x01234567 };
+  uint32_t x_out[4] = { 0xea2a92f4, 0xcb1cf8ce, 0x4581472e, 0x5881c4bb };
+  qround(x, 0, 1, 2, 3);
+  mi_assert_internal(array_equals(x, x_out, 4));
+
+  uint32_t y[16] = {
+       0x879531e0,  0xc5ecf37d,  0x516461b1,  0xc9a62f8a,
+       0x44c20ef3,  0x3390af7f,  0xd9fc690b,  0x2a5f714c,
+       0x53372767,  0xb00a5631,  0x974c541a,  0x359e9963,
+       0x5c971061,  0x3d631689,  0x2098d9d6,  0x91dbd320 };
+  uint32_t y_out[16] = {
+       0x879531e0,  0xc5ecf37d,  0xbdb886dc,  0xc9a62f8a,
+       0x44c20ef3,  0x3390af7f,  0xd9fc690b,  0xcfacafd2,
+       0xe46bea80,  0xb00a5631,  0x974c541a,  0x359e9963,
+       0x5c971061,  0xccc07c79,  0x2098d9d6,  0x91dbd320 };
+  qround(y, 2, 7, 8, 13);
+  mi_assert_internal(array_equals(y, y_out, 16));
+
+  mi_random_ctx_t r = {
+    { 0x61707865, 0x3320646e, 0x79622d32, 0x6b206574,
+      0x03020100, 0x07060504, 0x0b0a0908, 0x0f0e0d0c,
+      0x13121110, 0x17161514, 0x1b1a1918, 0x1f1e1d1c,
+      0x00000001, 0x09000000, 0x4a000000, 0x00000000 },
+    {0},
+    0
+  };
+  uint32_t r_out[16] = {
+       0xe4e7f110, 0x15593bd1, 0x1fdd0f50, 0xc47120a3,
+       0xc7f4d1c7, 0x0368c033, 0x9aaa2204, 0x4e6cd4c3,
+       0x466482d2, 0x09aa9f07, 0x05d7c214, 0xa2028bd9,
+       0xd19c12b5, 0xb94e16de, 0xe883d0cb, 0x4e3c50a2 };
+  chacha_block(&r);
+  mi_assert_internal(array_equals(r.output, r_out, 16));
+}
+*/
diff --git a/compat/mimalloc/segment-cache.c b/compat/mimalloc/segment-cache.c
new file mode 100644
index 00000000000000..e69de29bb2d1d6
diff --git a/compat/mimalloc/segment-map.c b/compat/mimalloc/segment-map.c
new file mode 100644
index 00000000000000..3cd2127e56c1a7
--- /dev/null
+++ b/compat/mimalloc/segment-map.c
@@ -0,0 +1,153 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2019-2023, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+
+/* -----------------------------------------------------------
+  The following functions are to reliably find the segment or
+  block that encompasses any pointer p (or NULL if it is not
+  in any of our segments).
+  We maintain a bitmap of all memory with 1 bit per MI_SEGMENT_SIZE (64MiB)
+  set to 1 if it contains the segment meta data.
+----------------------------------------------------------- */
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "mimalloc/atomic.h"
+
+#if (MI_INTPTR_SIZE==8)
+#define MI_MAX_ADDRESS    ((size_t)40 << 40)  // 40TB (to include huge page areas)
+#else
+#define MI_MAX_ADDRESS    ((size_t)2 << 30)   // 2Gb
+#endif
+
+#define MI_SEGMENT_MAP_BITS  (MI_MAX_ADDRESS / MI_SEGMENT_SIZE)
+#define MI_SEGMENT_MAP_SIZE  (MI_SEGMENT_MAP_BITS / 8)
+#define MI_SEGMENT_MAP_WSIZE (MI_SEGMENT_MAP_SIZE / MI_INTPTR_SIZE)
+
+static _Atomic(uintptr_t) mi_segment_map[MI_SEGMENT_MAP_WSIZE + 1];  // 2KiB per TB with 64MiB segments
+
+static size_t mi_segment_map_index_of(const mi_segment_t* segment, size_t* bitidx) {
+  mi_assert_internal(_mi_ptr_segment(segment + 1) == segment); // is it aligned on MI_SEGMENT_SIZE?
+  if ((uintptr_t)segment >= MI_MAX_ADDRESS) {
+    *bitidx = 0;
+    return MI_SEGMENT_MAP_WSIZE;
+  }
+  else {
+    const uintptr_t segindex = ((uintptr_t)segment) / MI_SEGMENT_SIZE;
+    *bitidx = segindex % MI_INTPTR_BITS;
+    const size_t mapindex = segindex / MI_INTPTR_BITS;
+    mi_assert_internal(mapindex < MI_SEGMENT_MAP_WSIZE);
+    return mapindex;
+  }
+}
+
+void _mi_segment_map_allocated_at(const mi_segment_t* segment) {
+  size_t bitidx;
+  size_t index = mi_segment_map_index_of(segment, &bitidx);
+  mi_assert_internal(index <= MI_SEGMENT_MAP_WSIZE);
+  if (index==MI_SEGMENT_MAP_WSIZE) return;
+  uintptr_t mask = mi_atomic_load_relaxed(&mi_segment_map[index]);
+  uintptr_t newmask;
+  do {
+    newmask = (mask | ((uintptr_t)1 << bitidx));
+  } while (!mi_atomic_cas_weak_release(&mi_segment_map[index], &mask, newmask));
+}
+
+void _mi_segment_map_freed_at(const mi_segment_t* segment) {
+  size_t bitidx;
+  size_t index = mi_segment_map_index_of(segment, &bitidx);
+  mi_assert_internal(index <= MI_SEGMENT_MAP_WSIZE);
+  if (index == MI_SEGMENT_MAP_WSIZE) return;
+  uintptr_t mask = mi_atomic_load_relaxed(&mi_segment_map[index]);
+  uintptr_t newmask;
+  do {
+    newmask = (mask & ~((uintptr_t)1 << bitidx));
+  } while (!mi_atomic_cas_weak_release(&mi_segment_map[index], &mask, newmask));
+}
+
+// Determine the segment belonging to a pointer or NULL if it is not in a valid segment.
+static mi_segment_t* _mi_segment_of(const void* p) {
+  if (p == NULL) return NULL;
+  mi_segment_t* segment = _mi_ptr_segment(p);
+  mi_assert_internal(segment != NULL);
+  size_t bitidx;
+  size_t index = mi_segment_map_index_of(segment, &bitidx);
+  // fast path: for any pointer to valid small/medium/large object or first MI_SEGMENT_SIZE in huge
+  const uintptr_t mask = mi_atomic_load_relaxed(&mi_segment_map[index]);
+  if mi_likely((mask & ((uintptr_t)1 << bitidx)) != 0) {
+    return segment; // yes, allocated by us
+  }
+  if (index==MI_SEGMENT_MAP_WSIZE) return NULL;
+
+  // TODO: maintain max/min allocated range for efficiency for more efficient rejection of invalid pointers?
+
+  // search downwards for the first segment in case it is an interior pointer
+  // could be slow but searches in MI_INTPTR_SIZE * MI_SEGMENT_SIZE (512MiB) steps trough
+  // valid huge objects
+  // note: we could maintain a lowest index to speed up the path for invalid pointers?
+  size_t lobitidx;
+  size_t loindex;
+  uintptr_t lobits = mask & (((uintptr_t)1 << bitidx) - 1);
+  if (lobits != 0) {
+    loindex = index;
+    lobitidx = mi_bsr(lobits);    // lobits != 0
+  }
+  else if (index == 0) {
+    return NULL;
+  }
+  else {
+    mi_assert_internal(index > 0);
+    uintptr_t lomask = mask;
+    loindex = index;
+    do {
+      loindex--;
+      lomask = mi_atomic_load_relaxed(&mi_segment_map[loindex]);
+    } while (lomask != 0 && loindex > 0);
+    if (lomask == 0) return NULL;
+    lobitidx = mi_bsr(lomask);    // lomask != 0
+  }
+  mi_assert_internal(loindex < MI_SEGMENT_MAP_WSIZE);
+  // take difference as the addresses could be larger than the MAX_ADDRESS space.
+  size_t diff = (((index - loindex) * (8*MI_INTPTR_SIZE)) + bitidx - lobitidx) * MI_SEGMENT_SIZE;
+  segment = (mi_segment_t*)((uint8_t*)segment - diff);
+
+  if (segment == NULL) return NULL;
+  mi_assert_internal((void*)segment < p);
+  bool cookie_ok = (_mi_ptr_cookie(segment) == segment->cookie);
+  mi_assert_internal(cookie_ok);
+  if mi_unlikely(!cookie_ok) return NULL;
+  if (((uint8_t*)segment + mi_segment_size(segment)) <= (uint8_t*)p) return NULL; // outside the range
+  mi_assert_internal(p >= (void*)segment && (uint8_t*)p < (uint8_t*)segment + mi_segment_size(segment));
+  return segment;
+}
+
+// Is this a valid pointer in our heap?
+static bool  mi_is_valid_pointer(const void* p) {
+  return ((_mi_segment_of(p) != NULL) || (_mi_arena_contains(p)));
+}
+
+mi_decl_nodiscard mi_decl_export bool mi_is_in_heap_region(const void* p) mi_attr_noexcept {
+  return mi_is_valid_pointer(p);
+}
+
+/*
+// Return the full segment range belonging to a pointer
+static void* mi_segment_range_of(const void* p, size_t* size) {
+  mi_segment_t* segment = _mi_segment_of(p);
+  if (segment == NULL) {
+    if (size != NULL) *size = 0;
+    return NULL;
+  }
+  else {
+    if (size != NULL) *size = segment->segment_size;
+    return segment;
+  }
+  mi_assert_expensive(page == NULL || mi_segment_is_valid(_mi_page_segment(page),tld));
+  mi_assert_internal(page == NULL || (mi_segment_page_size(_mi_page_segment(page)) - (MI_SECURE == 0 ? 0 : _mi_os_page_size())) >= block_size);
+  mi_reset_delayed(tld);
+  mi_assert_internal(page == NULL || mi_page_not_in_queue(page, tld));
+  return page;
+}
+*/
diff --git a/compat/mimalloc/segment.c b/compat/mimalloc/segment.c
new file mode 100644
index 00000000000000..6b901f6cc80f13
--- /dev/null
+++ b/compat/mimalloc/segment.c
@@ -0,0 +1,1617 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2020, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "mimalloc/atomic.h"
+
+#include <string.h>  // memset
+#include <stdio.h>
+
+#define MI_PAGE_HUGE_ALIGN   (256*1024)
+
+static void mi_segment_try_purge(mi_segment_t* segment, bool force, mi_stats_t* stats);
+
+
+// -------------------------------------------------------------------
+// commit mask
+// -------------------------------------------------------------------
+
+static bool mi_commit_mask_all_set(const mi_commit_mask_t* commit, const mi_commit_mask_t* cm) {
+  for (size_t i = 0; i < MI_COMMIT_MASK_FIELD_COUNT; i++) {
+    if ((commit->mask[i] & cm->mask[i]) != cm->mask[i]) return false;
+  }
+  return true;
+}
+
+static bool mi_commit_mask_any_set(const mi_commit_mask_t* commit, const mi_commit_mask_t* cm) {
+  for (size_t i = 0; i < MI_COMMIT_MASK_FIELD_COUNT; i++) {
+    if ((commit->mask[i] & cm->mask[i]) != 0) return true;
+  }
+  return false;
+}
+
+static void mi_commit_mask_create_intersect(const mi_commit_mask_t* commit, const mi_commit_mask_t* cm, mi_commit_mask_t* res) {
+  for (size_t i = 0; i < MI_COMMIT_MASK_FIELD_COUNT; i++) {
+    res->mask[i] = (commit->mask[i] & cm->mask[i]);
+  }
+}
+
+static void mi_commit_mask_clear(mi_commit_mask_t* res, const mi_commit_mask_t* cm) {
+  for (size_t i = 0; i < MI_COMMIT_MASK_FIELD_COUNT; i++) {
+    res->mask[i] &= ~(cm->mask[i]);
+  }
+}
+
+static void mi_commit_mask_set(mi_commit_mask_t* res, const mi_commit_mask_t* cm) {
+  for (size_t i = 0; i < MI_COMMIT_MASK_FIELD_COUNT; i++) {
+    res->mask[i] |= cm->mask[i];
+  }
+}
+
+static void mi_commit_mask_create(size_t bitidx, size_t bitcount, mi_commit_mask_t* cm) {
+  mi_assert_internal(bitidx < MI_COMMIT_MASK_BITS);
+  mi_assert_internal((bitidx + bitcount) <= MI_COMMIT_MASK_BITS);
+  if (bitcount == MI_COMMIT_MASK_BITS) {
+    mi_assert_internal(bitidx==0);
+    mi_commit_mask_create_full(cm);
+  }
+  else if (bitcount == 0) {
+    mi_commit_mask_create_empty(cm);
+  }
+  else {
+    mi_commit_mask_create_empty(cm);
+    size_t i = bitidx / MI_COMMIT_MASK_FIELD_BITS;
+    size_t ofs = bitidx % MI_COMMIT_MASK_FIELD_BITS;
+    while (bitcount > 0) {
+      mi_assert_internal(i < MI_COMMIT_MASK_FIELD_COUNT);
+      size_t avail = MI_COMMIT_MASK_FIELD_BITS - ofs;
+      size_t count = (bitcount > avail ? avail : bitcount);
+      size_t mask = (count >= MI_COMMIT_MASK_FIELD_BITS ? ~((size_t)0) : (((size_t)1 << count) - 1) << ofs);
+      cm->mask[i] = mask;
+      bitcount -= count;
+      ofs = 0;
+      i++;
+    }
+  }
+}
+
+size_t _mi_commit_mask_committed_size(const mi_commit_mask_t* cm, size_t total) {
+  mi_assert_internal((total%MI_COMMIT_MASK_BITS)==0);
+  size_t count = 0;
+  for (size_t i = 0; i < MI_COMMIT_MASK_FIELD_COUNT; i++) {
+    size_t mask = cm->mask[i];
+    if (~mask == 0) {
+      count += MI_COMMIT_MASK_FIELD_BITS;
+    }
+    else {
+      for (; mask != 0; mask >>= 1) {  // todo: use popcount
+	if ((mask&1)!=0) count++;
+      }
+    }
+  }
+  // we use total since for huge segments each commit bit may represent a larger size
+  return ((total / MI_COMMIT_MASK_BITS) * count);
+}
+
+
+size_t _mi_commit_mask_next_run(const mi_commit_mask_t* cm, size_t* idx) {
+  size_t i = (*idx) / MI_COMMIT_MASK_FIELD_BITS;
+  size_t ofs = (*idx) % MI_COMMIT_MASK_FIELD_BITS;
+  size_t mask = 0;
+  // find first ones
+  while (i < MI_COMMIT_MASK_FIELD_COUNT) {
+    mask = cm->mask[i];
+    mask >>= ofs;
+    if (mask != 0) {
+      while ((mask&1) == 0) {
+	mask >>= 1;
+	ofs++;
+      }
+      break;
+    }
+    i++;
+    ofs = 0;
+  }
+  if (i >= MI_COMMIT_MASK_FIELD_COUNT) {
+    // not found
+    *idx = MI_COMMIT_MASK_BITS;
+    return 0;
+  }
+  else {
+    // found, count ones
+    size_t count = 0;
+    *idx = (i*MI_COMMIT_MASK_FIELD_BITS) + ofs;
+    do {
+      mi_assert_internal(ofs < MI_COMMIT_MASK_FIELD_BITS && (mask&1) == 1);
+      do {
+	count++;
+	mask >>= 1;
+      } while ((mask&1) == 1);
+      if ((((*idx + count) % MI_COMMIT_MASK_FIELD_BITS) == 0)) {
+	i++;
+	if (i >= MI_COMMIT_MASK_FIELD_COUNT) break;
+	mask = cm->mask[i];
+	ofs = 0;
+      }
+    } while ((mask&1) == 1);
+    mi_assert_internal(count > 0);
+    return count;
+  }
+}
+
+
+/* --------------------------------------------------------------------------------
+  Segment allocation
+
+  If a  thread ends, it "abandons" pages with used blocks
+  and there is an abandoned segment list whose segments can
+  be reclaimed by still running threads, much like work-stealing.
+-------------------------------------------------------------------------------- */
+
+
+/* -----------------------------------------------------------
+   Slices
+----------------------------------------------------------- */
+
+
+static const mi_slice_t* mi_segment_slices_end(const mi_segment_t* segment) {
+  return &segment->slices[segment->slice_entries];
+}
+
+static uint8_t* mi_slice_start(const mi_slice_t* slice) {
+  mi_segment_t* segment = _mi_ptr_segment(slice);
+  mi_assert_internal(slice >= segment->slices && slice < mi_segment_slices_end(segment));
+  return ((uint8_t*)segment + ((slice - segment->slices)*MI_SEGMENT_SLICE_SIZE));
+}
+
+
+/* -----------------------------------------------------------
+   Bins
+----------------------------------------------------------- */
+// Use bit scan forward to quickly find the first zero bit if it is available
+
+static inline size_t mi_slice_bin8(size_t slice_count) {
+  if (slice_count<=1) return slice_count;
+  mi_assert_internal(slice_count <= MI_SLICES_PER_SEGMENT);
+  slice_count--;
+  size_t s = mi_bsr(slice_count);  // slice_count > 1
+  if (s <= 2) return slice_count + 1;
+  size_t bin = ((s << 2) | ((slice_count >> (s - 2))&0x03)) - 4;
+  return bin;
+}
+
+static inline size_t mi_slice_bin(size_t slice_count) {
+  mi_assert_internal(slice_count*MI_SEGMENT_SLICE_SIZE <= MI_SEGMENT_SIZE);
+  mi_assert_internal(mi_slice_bin8(MI_SLICES_PER_SEGMENT) <= MI_SEGMENT_BIN_MAX);
+  size_t bin = mi_slice_bin8(slice_count);
+  mi_assert_internal(bin <= MI_SEGMENT_BIN_MAX);
+  return bin;
+}
+
+static inline size_t mi_slice_index(const mi_slice_t* slice) {
+  mi_segment_t* segment = _mi_ptr_segment(slice);
+  ptrdiff_t index = slice - segment->slices;
+  mi_assert_internal(index >= 0 && index < (ptrdiff_t)segment->slice_entries);
+  return index;
+}
+
+
+/* -----------------------------------------------------------
+   Slice span queues
+----------------------------------------------------------- */
+
+static void mi_span_queue_push(mi_span_queue_t* sq, mi_slice_t* slice) {
+  // todo: or push to the end?
+  mi_assert_internal(slice->prev == NULL && slice->next==NULL);
+  slice->prev = NULL; // paranoia
+  slice->next = sq->first;
+  sq->first = slice;
+  if (slice->next != NULL) slice->next->prev = slice;
+		     else sq->last = slice;
+  slice->xblock_size = 0; // free
+}
+
+static mi_span_queue_t* mi_span_queue_for(size_t slice_count, mi_segments_tld_t* tld) {
+  size_t bin = mi_slice_bin(slice_count);
+  mi_span_queue_t* sq = &tld->spans[bin];
+  mi_assert_internal(sq->slice_count >= slice_count);
+  return sq;
+}
+
+static void mi_span_queue_delete(mi_span_queue_t* sq, mi_slice_t* slice) {
+  mi_assert_internal(slice->xblock_size==0 && slice->slice_count>0 && slice->slice_offset==0);
+  // should work too if the queue does not contain slice (which can happen during reclaim)
+  if (slice->prev != NULL) slice->prev->next = slice->next;
+  if (slice == sq->first) sq->first = slice->next;
+  if (slice->next != NULL) slice->next->prev = slice->prev;
+  if (slice == sq->last) sq->last = slice->prev;
+  slice->prev = NULL;
+  slice->next = NULL;
+  slice->xblock_size = 1; // no more free
+}
+
+
+/* -----------------------------------------------------------
+ Invariant checking
+----------------------------------------------------------- */
+
+static bool mi_slice_is_used(const mi_slice_t* slice) {
+  return (slice->xblock_size > 0);
+}
+
+
+#if (MI_DEBUG>=3)
+static bool mi_span_queue_contains(mi_span_queue_t* sq, mi_slice_t* slice) {
+  for (mi_slice_t* s = sq->first; s != NULL; s = s->next) {
+    if (s==slice) return true;
+  }
+  return false;
+}
+
+static bool mi_segment_is_valid(mi_segment_t* segment, mi_segments_tld_t* tld) {
+  mi_assert_internal(segment != NULL);
+  mi_assert_internal(_mi_ptr_cookie(segment) == segment->cookie);
+  mi_assert_internal(segment->abandoned <= segment->used);
+  mi_assert_internal(segment->thread_id == 0 || segment->thread_id == _mi_thread_id());
+  mi_assert_internal(mi_commit_mask_all_set(&segment->commit_mask, &segment->purge_mask)); // can only decommit committed blocks
+  //mi_assert_internal(segment->segment_info_size % MI_SEGMENT_SLICE_SIZE == 0);
+  mi_slice_t* slice = &segment->slices[0];
+  const mi_slice_t* end = mi_segment_slices_end(segment);
+  size_t used_count = 0;
+  mi_span_queue_t* sq;
+  while(slice < end) {
+    mi_assert_internal(slice->slice_count > 0);
+    mi_assert_internal(slice->slice_offset == 0);
+    size_t index = mi_slice_index(slice);
+    size_t maxindex = (index + slice->slice_count >= segment->slice_entries ? segment->slice_entries : index + slice->slice_count) - 1;
+    if (mi_slice_is_used(slice)) { // a page in use, we need at least MAX_SLICE_OFFSET valid back offsets
+      used_count++;
+      for (size_t i = 0; i <= MI_MAX_SLICE_OFFSET && index + i <= maxindex; i++) {
+	mi_assert_internal(segment->slices[index + i].slice_offset == i*sizeof(mi_slice_t));
+	mi_assert_internal(i==0 || segment->slices[index + i].slice_count == 0);
+	mi_assert_internal(i==0 || segment->slices[index + i].xblock_size == 1);
+      }
+      // and the last entry as well (for coalescing)
+      const mi_slice_t* last = slice + slice->slice_count - 1;
+      if (last > slice && last < mi_segment_slices_end(segment)) {
+	mi_assert_internal(last->slice_offset == (slice->slice_count-1)*sizeof(mi_slice_t));
+	mi_assert_internal(last->slice_count == 0);
+	mi_assert_internal(last->xblock_size == 1);
+      }
+    }
+    else {  // free range of slices; only last slice needs a valid back offset
+      mi_slice_t* last = &segment->slices[maxindex];
+      if (segment->kind != MI_SEGMENT_HUGE || slice->slice_count <= (segment->slice_entries - segment->segment_info_slices)) {
+	mi_assert_internal((uint8_t*)slice == (uint8_t*)last - last->slice_offset);
+      }
+      mi_assert_internal(slice == last || last->slice_count == 0 );
+      mi_assert_internal(last->xblock_size == 0 || (segment->kind==MI_SEGMENT_HUGE && last->xblock_size==1));
+      if (segment->kind != MI_SEGMENT_HUGE && segment->thread_id != 0) { // segment is not huge or abandoned
+	sq = mi_span_queue_for(slice->slice_count,tld);
+	mi_assert_internal(mi_span_queue_contains(sq,slice));
+      }
+    }
+    slice = &segment->slices[maxindex+1];
+  }
+  mi_assert_internal(slice == end);
+  mi_assert_internal(used_count == segment->used + 1);
+  return true;
+}
+#endif
+
+/* -----------------------------------------------------------
+ Segment size calculations
+----------------------------------------------------------- */
+
+static size_t mi_segment_info_size(mi_segment_t* segment) {
+  return segment->segment_info_slices * MI_SEGMENT_SLICE_SIZE;
+}
+
+static uint8_t* _mi_segment_page_start_from_slice(const mi_segment_t* segment, const mi_slice_t* slice, size_t xblock_size, size_t* page_size)
+{
+  ptrdiff_t idx = slice - segment->slices;
+  size_t psize = (size_t)slice->slice_count * MI_SEGMENT_SLICE_SIZE;
+  // make the start not OS page aligned for smaller blocks to avoid page/cache effects
+  // note: the offset must always be an xblock_size multiple since we assume small allocations
+  // are aligned (see `mi_heap_malloc_aligned`).
+  size_t start_offset = 0;
+  if (xblock_size >= MI_INTPTR_SIZE) {
+    if (xblock_size <= 64) { start_offset = 3*xblock_size; }
+    else if (xblock_size <= 512) { start_offset = xblock_size; }
+  }
+  if (page_size != NULL) { *page_size = psize - start_offset; }
+  return (uint8_t*)segment + ((idx*MI_SEGMENT_SLICE_SIZE) + start_offset);
+}
+
+// Start of the page available memory; can be used on uninitialized pages
+uint8_t* _mi_segment_page_start(const mi_segment_t* segment, const mi_page_t* page, size_t* page_size)
+{
+  const mi_slice_t* slice = mi_page_to_slice((mi_page_t*)page);
+  uint8_t* p = _mi_segment_page_start_from_slice(segment, slice, page->xblock_size, page_size);
+  mi_assert_internal(page->xblock_size > 0 || _mi_ptr_page(p) == page);
+  mi_assert_internal(_mi_ptr_segment(p) == segment);
+  return p;
+}
+
+
+static size_t mi_segment_calculate_slices(size_t required, size_t* pre_size, size_t* info_slices) {
+  size_t page_size = _mi_os_page_size();
+  size_t isize     = _mi_align_up(sizeof(mi_segment_t), page_size);
+  size_t guardsize = 0;
+
+  if (MI_SECURE>0) {
+    // in secure mode, we set up a protected page in between the segment info
+    // and the page data (and one at the end of the segment)
+    guardsize = page_size;
+    if (required > 0) {
+      required = _mi_align_up(required, MI_SEGMENT_SLICE_SIZE) + page_size;
+    }
+  }
+
+  if (pre_size != NULL) *pre_size = isize;
+  isize = _mi_align_up(isize + guardsize, MI_SEGMENT_SLICE_SIZE);
+  if (info_slices != NULL) *info_slices = isize / MI_SEGMENT_SLICE_SIZE;
+  size_t segment_size = (required==0 ? MI_SEGMENT_SIZE : _mi_align_up( required + isize + guardsize, MI_SEGMENT_SLICE_SIZE) );
+  mi_assert_internal(segment_size % MI_SEGMENT_SLICE_SIZE == 0);
+  return (segment_size / MI_SEGMENT_SLICE_SIZE);
+}
+
+
+/* ----------------------------------------------------------------------------
+Segment caches
+We keep a small segment cache per thread to increase local
+reuse and avoid setting/clearing guard pages in secure mode.
+------------------------------------------------------------------------------- */
+
+static void mi_segments_track_size(long segment_size, mi_segments_tld_t* tld) {
+  if (segment_size>=0) _mi_stat_increase(&tld->stats->segments,1);
+		  else _mi_stat_decrease(&tld->stats->segments,1);
+  tld->count += (segment_size >= 0 ? 1 : -1);
+  if (tld->count > tld->peak_count) tld->peak_count = tld->count;
+  tld->current_size += segment_size;
+  if (tld->current_size > tld->peak_size) tld->peak_size = tld->current_size;
+}
+
+static void mi_segment_os_free(mi_segment_t* segment, mi_segments_tld_t* tld) {
+  segment->thread_id = 0;
+  _mi_segment_map_freed_at(segment);
+  mi_segments_track_size(-((long)mi_segment_size(segment)),tld);
+  if (MI_SECURE>0) {
+    // _mi_os_unprotect(segment, mi_segment_size(segment)); // ensure no more guard pages are set
+    // unprotect the guard pages; we cannot just unprotect the whole segment size as part may be decommitted
+    size_t os_pagesize = _mi_os_page_size();
+    _mi_os_unprotect((uint8_t*)segment + mi_segment_info_size(segment) - os_pagesize, os_pagesize);
+    uint8_t* end = (uint8_t*)segment + mi_segment_size(segment) - os_pagesize;
+    _mi_os_unprotect(end, os_pagesize);
+  }
+
+  // purge delayed decommits now? (no, leave it to the arena)
+  // mi_segment_try_purge(segment,true,tld->stats);
+
+  const size_t size = mi_segment_size(segment);
+  const size_t csize = _mi_commit_mask_committed_size(&segment->commit_mask, size);
+
+  _mi_abandoned_await_readers();  // wait until safe to free
+  _mi_arena_free(segment, mi_segment_size(segment), csize, segment->memid, tld->stats);
+}
+
+// called by threads that are terminating
+void _mi_segment_thread_collect(mi_segments_tld_t* tld) {
+  MI_UNUSED(tld);
+  // nothing to do
+}
+
+
+/* -----------------------------------------------------------
+   Commit/Decommit ranges
+----------------------------------------------------------- */
+
+static void mi_segment_commit_mask(mi_segment_t* segment, bool conservative, uint8_t* p, size_t size, uint8_t** start_p, size_t* full_size, mi_commit_mask_t* cm) {
+  mi_assert_internal(_mi_ptr_segment(p + 1) == segment);
+  mi_assert_internal(segment->kind != MI_SEGMENT_HUGE);
+  mi_commit_mask_create_empty(cm);
+  if (size == 0 || size > MI_SEGMENT_SIZE || segment->kind == MI_SEGMENT_HUGE) return;
+  const size_t segstart = mi_segment_info_size(segment);
+  const size_t segsize = mi_segment_size(segment);
+  if (p >= (uint8_t*)segment + segsize) return;
+
+  size_t pstart = (p - (uint8_t*)segment);
+  mi_assert_internal(pstart + size <= segsize);
+
+  size_t start;
+  size_t end;
+  if (conservative) {
+    // decommit conservative
+    start = _mi_align_up(pstart, MI_COMMIT_SIZE);
+    end   = _mi_align_down(pstart + size, MI_COMMIT_SIZE);
+    mi_assert_internal(start >= segstart);
+    mi_assert_internal(end <= segsize);
+  }
+  else {
+    // commit liberal
+    start = _mi_align_down(pstart, MI_MINIMAL_COMMIT_SIZE);
+    end   = _mi_align_up(pstart + size, MI_MINIMAL_COMMIT_SIZE);
+  }
+  if (pstart >= segstart && start < segstart) {  // note: the mask is also calculated for an initial commit of the info area
+    start = segstart;
+  }
+  if (end > segsize) {
+    end = segsize;
+  }
+
+  mi_assert_internal(start <= pstart && (pstart + size) <= end);
+  mi_assert_internal(start % MI_COMMIT_SIZE==0 && end % MI_COMMIT_SIZE == 0);
+  *start_p   = (uint8_t*)segment + start;
+  *full_size = (end > start ? end - start : 0);
+  if (*full_size == 0) return;
+
+  size_t bitidx = start / MI_COMMIT_SIZE;
+  mi_assert_internal(bitidx < MI_COMMIT_MASK_BITS);
+
+  size_t bitcount = *full_size / MI_COMMIT_SIZE; // can be 0
+  if (bitidx + bitcount > MI_COMMIT_MASK_BITS) {
+    _mi_warning_message("commit mask overflow: idx=%zu count=%zu start=%zx end=%zx p=0x%p size=%zu fullsize=%zu\n", bitidx, bitcount, start, end, p, size, *full_size);
+  }
+  mi_assert_internal((bitidx + bitcount) <= MI_COMMIT_MASK_BITS);
+  mi_commit_mask_create(bitidx, bitcount, cm);
+}
+
+static bool mi_segment_commit(mi_segment_t* segment, uint8_t* p, size_t size, mi_stats_t* stats) {
+  mi_assert_internal(mi_commit_mask_all_set(&segment->commit_mask, &segment->purge_mask));
+
+  // commit liberal
+  uint8_t* start = NULL;
+  size_t   full_size = 0;
+  mi_commit_mask_t mask;
+  mi_segment_commit_mask(segment, false /* conservative? */, p, size, &start, &full_size, &mask);
+  if (mi_commit_mask_is_empty(&mask) || full_size == 0) return true;
+
+  if (!mi_commit_mask_all_set(&segment->commit_mask, &mask)) {
+    // committing
+    bool is_zero = false;
+    mi_commit_mask_t cmask;
+    mi_commit_mask_create_intersect(&segment->commit_mask, &mask, &cmask);
+    _mi_stat_decrease(&_mi_stats_main.committed, _mi_commit_mask_committed_size(&cmask, MI_SEGMENT_SIZE)); // adjust for overlap
+    if (!_mi_os_commit(start, full_size, &is_zero, stats)) return false;
+    mi_commit_mask_set(&segment->commit_mask, &mask);
+  }
+
+  // increase purge expiration when using part of delayed purges -- we assume more allocations are coming soon.
+  if (mi_commit_mask_any_set(&segment->purge_mask, &mask)) {
+    segment->purge_expire = _mi_clock_now() + mi_option_get(mi_option_purge_delay);
+  }
+
+  // always clear any delayed purges in our range (as they are either committed now)
+  mi_commit_mask_clear(&segment->purge_mask, &mask);
+  return true;
+}
+
+static bool mi_segment_ensure_committed(mi_segment_t* segment, uint8_t* p, size_t size, mi_stats_t* stats) {
+  mi_assert_internal(mi_commit_mask_all_set(&segment->commit_mask, &segment->purge_mask));
+  // note: assumes commit_mask is always full for huge segments as otherwise the commit mask bits can overflow
+  if (mi_commit_mask_is_full(&segment->commit_mask) && mi_commit_mask_is_empty(&segment->purge_mask)) return true; // fully committed
+  mi_assert_internal(segment->kind != MI_SEGMENT_HUGE);
+  return mi_segment_commit(segment, p, size, stats);
+}
+
+static bool mi_segment_purge(mi_segment_t* segment, uint8_t* p, size_t size, mi_stats_t* stats) {
+  mi_assert_internal(mi_commit_mask_all_set(&segment->commit_mask, &segment->purge_mask));
+  if (!segment->allow_purge) return true;
+
+  // purge conservative
+  uint8_t* start = NULL;
+  size_t   full_size = 0;
+  mi_commit_mask_t mask;
+  mi_segment_commit_mask(segment, true /* conservative? */, p, size, &start, &full_size, &mask);
+  if (mi_commit_mask_is_empty(&mask) || full_size==0) return true;
+
+  if (mi_commit_mask_any_set(&segment->commit_mask, &mask)) {
+    // purging
+    mi_assert_internal((void*)start != (void*)segment);
+    mi_assert_internal(segment->allow_decommit);
+    const bool decommitted = _mi_os_purge(start, full_size, stats);  // reset or decommit
+    if (decommitted) {
+      mi_commit_mask_t cmask;
+      mi_commit_mask_create_intersect(&segment->commit_mask, &mask, &cmask);
+      _mi_stat_increase(&_mi_stats_main.committed, full_size - _mi_commit_mask_committed_size(&cmask, MI_SEGMENT_SIZE)); // adjust for double counting
+      mi_commit_mask_clear(&segment->commit_mask, &mask);
+    }
+  }
+
+  // always clear any scheduled purges in our range
+  mi_commit_mask_clear(&segment->purge_mask, &mask);
+  return true;
+}
+
+static void mi_segment_schedule_purge(mi_segment_t* segment, uint8_t* p, size_t size, mi_stats_t* stats) {
+  if (!segment->allow_purge) return;
+
+  if (mi_option_get(mi_option_purge_delay) == 0) {
+    mi_segment_purge(segment, p, size, stats);
+  }
+  else {
+    // register for future purge in the purge mask
+    uint8_t* start = NULL;
+    size_t   full_size = 0;
+    mi_commit_mask_t mask;
+    mi_segment_commit_mask(segment, true /*conservative*/, p, size, &start, &full_size, &mask);
+    if (mi_commit_mask_is_empty(&mask) || full_size==0) return;
+
+    // update delayed commit
+    mi_assert_internal(segment->purge_expire > 0 || mi_commit_mask_is_empty(&segment->purge_mask));
+    mi_commit_mask_t cmask;
+    mi_commit_mask_create_intersect(&segment->commit_mask, &mask, &cmask);  // only purge what is committed; span_free may try to decommit more
+    mi_commit_mask_set(&segment->purge_mask, &cmask);
+    mi_msecs_t now = _mi_clock_now();
+    if (segment->purge_expire == 0) {
+      // no previous purgess, initialize now
+      segment->purge_expire = now + mi_option_get(mi_option_purge_delay);
+    }
+    else if (segment->purge_expire <= now) {
+      // previous purge mask already expired
+      if (segment->purge_expire + mi_option_get(mi_option_purge_extend_delay) <= now) {
+	mi_segment_try_purge(segment, true, stats);
+      }
+      else {
+	segment->purge_expire = now + mi_option_get(mi_option_purge_extend_delay); // (mi_option_get(mi_option_purge_delay) / 8); // wait a tiny bit longer in case there is a series of free's
+      }
+    }
+    else {
+      // previous purge mask is not yet expired, increase the expiration by a bit.
+      segment->purge_expire += mi_option_get(mi_option_purge_extend_delay);
+    }
+  }
+}
+
+static void mi_segment_try_purge(mi_segment_t* segment, bool force, mi_stats_t* stats) {
+  if (!segment->allow_purge || mi_commit_mask_is_empty(&segment->purge_mask)) return;
+  mi_msecs_t now = _mi_clock_now();
+  if (!force && now < segment->purge_expire) return;
+
+  mi_commit_mask_t mask = segment->purge_mask;
+  segment->purge_expire = 0;
+  mi_commit_mask_create_empty(&segment->purge_mask);
+
+  size_t idx;
+  size_t count;
+  mi_commit_mask_foreach(&mask, idx, count) {
+    // if found, decommit that sequence
+    if (count > 0) {
+      uint8_t* p = (uint8_t*)segment + (idx*MI_COMMIT_SIZE);
+      size_t size = count * MI_COMMIT_SIZE;
+      mi_segment_purge(segment, p, size, stats);
+    }
+  }
+  mi_commit_mask_foreach_end()
+  mi_assert_internal(mi_commit_mask_is_empty(&segment->purge_mask));
+}
+
+
+/* -----------------------------------------------------------
+   Span free
+----------------------------------------------------------- */
+
+static bool mi_segment_is_abandoned(mi_segment_t* segment) {
+  return (segment->thread_id == 0);
+}
+
+// note: can be called on abandoned segments
+static void mi_segment_span_free(mi_segment_t* segment, size_t slice_index, size_t slice_count, bool allow_purge, mi_segments_tld_t* tld) {
+  mi_assert_internal(slice_index < segment->slice_entries);
+  mi_span_queue_t* sq = (segment->kind == MI_SEGMENT_HUGE || mi_segment_is_abandoned(segment)
+			  ? NULL : mi_span_queue_for(slice_count,tld));
+  if (slice_count==0) slice_count = 1;
+  mi_assert_internal(slice_index + slice_count - 1 < segment->slice_entries);
+
+  // set first and last slice (the intermediates can be undetermined)
+  mi_slice_t* slice = &segment->slices[slice_index];
+  slice->slice_count = (uint32_t)slice_count;
+  mi_assert_internal(slice->slice_count == slice_count); // no overflow?
+  slice->slice_offset = 0;
+  if (slice_count > 1) {
+    mi_slice_t* last = &segment->slices[slice_index + slice_count - 1];
+    last->slice_count = 0;
+    last->slice_offset = (uint32_t)(sizeof(mi_page_t)*(slice_count - 1));
+    last->xblock_size = 0;
+  }
+
+  // perhaps decommit
+  if (allow_purge) {
+    mi_segment_schedule_purge(segment, mi_slice_start(slice), slice_count * MI_SEGMENT_SLICE_SIZE, tld->stats);
+  }
+
+  // and push it on the free page queue (if it was not a huge page)
+  if (sq != NULL) mi_span_queue_push( sq, slice );
+	     else slice->xblock_size = 0; // mark huge page as free anyways
+}
+
+/*
+// called from reclaim to add existing free spans
+static void mi_segment_span_add_free(mi_slice_t* slice, mi_segments_tld_t* tld) {
+  mi_segment_t* segment = _mi_ptr_segment(slice);
+  mi_assert_internal(slice->xblock_size==0 && slice->slice_count>0 && slice->slice_offset==0);
+  size_t slice_index = mi_slice_index(slice);
+  mi_segment_span_free(segment,slice_index,slice->slice_count,tld);
+}
+*/
+
+static void mi_segment_span_remove_from_queue(mi_slice_t* slice, mi_segments_tld_t* tld) {
+  mi_assert_internal(slice->slice_count > 0 && slice->slice_offset==0 && slice->xblock_size==0);
+  mi_assert_internal(_mi_ptr_segment(slice)->kind != MI_SEGMENT_HUGE);
+  mi_span_queue_t* sq = mi_span_queue_for(slice->slice_count, tld);
+  mi_span_queue_delete(sq, slice);
+}
+
+// note: can be called on abandoned segments
+static mi_slice_t* mi_segment_span_free_coalesce(mi_slice_t* slice, mi_segments_tld_t* tld) {
+  mi_assert_internal(slice != NULL && slice->slice_count > 0 && slice->slice_offset == 0);
+  mi_segment_t* segment = _mi_ptr_segment(slice);
+  bool is_abandoned = mi_segment_is_abandoned(segment);
+
+  // for huge pages, just mark as free but don't add to the queues
+  if (segment->kind == MI_SEGMENT_HUGE) {
+    // issue #691: segment->used can be 0 if the huge page block was freed while abandoned (reclaim will get here in that case)
+    mi_assert_internal((segment->used==0 && slice->xblock_size==0) || segment->used == 1);  // decreased right after this call in `mi_segment_page_clear`
+    slice->xblock_size = 0;  // mark as free anyways
+    // we should mark the last slice `xblock_size=0` now to maintain invariants but we skip it to
+    // avoid a possible cache miss (and the segment is about to be freed)
+    return slice;
+  }
+
+  // otherwise coalesce the span and add to the free span queues
+  size_t slice_count = slice->slice_count;
+  mi_slice_t* next = slice + slice->slice_count;
+  mi_assert_internal(next <= mi_segment_slices_end(segment));
+  if (next < mi_segment_slices_end(segment) && next->xblock_size==0) {
+    // free next block -- remove it from free and merge
+    mi_assert_internal(next->slice_count > 0 && next->slice_offset==0);
+    slice_count += next->slice_count; // extend
+    if (!is_abandoned) { mi_segment_span_remove_from_queue(next, tld); }
+  }
+  if (slice > segment->slices) {
+    mi_slice_t* prev = mi_slice_first(slice - 1);
+    mi_assert_internal(prev >= segment->slices);
+    if (prev->xblock_size==0) {
+      // free previous slice -- remove it from free and merge
+      mi_assert_internal(prev->slice_count > 0 && prev->slice_offset==0);
+      slice_count += prev->slice_count;
+      if (!is_abandoned) { mi_segment_span_remove_from_queue(prev, tld); }
+      slice = prev;
+    }
+  }
+
+  // and add the new free page
+  mi_segment_span_free(segment, mi_slice_index(slice), slice_count, true, tld);
+  return slice;
+}
+
+
+
+/* -----------------------------------------------------------
+   Page allocation
+----------------------------------------------------------- */
+
+// Note: may still return NULL if committing the memory failed
+static mi_page_t* mi_segment_span_allocate(mi_segment_t* segment, size_t slice_index, size_t slice_count, mi_segments_tld_t* tld) {
+  mi_assert_internal(slice_index < segment->slice_entries);
+  mi_slice_t* const slice = &segment->slices[slice_index];
+  mi_assert_internal(slice->xblock_size==0 || slice->xblock_size==1);
+
+  // commit before changing the slice data
+  if (!mi_segment_ensure_committed(segment, _mi_segment_page_start_from_slice(segment, slice, 0, NULL), slice_count * MI_SEGMENT_SLICE_SIZE, tld->stats)) {
+    return NULL;  // commit failed!
+  }
+
+  // convert the slices to a page
+  slice->slice_offset = 0;
+  slice->slice_count = (uint32_t)slice_count;
+  mi_assert_internal(slice->slice_count == slice_count);
+  const size_t bsize = slice_count * MI_SEGMENT_SLICE_SIZE;
+  slice->xblock_size = (uint32_t)(bsize >= MI_HUGE_BLOCK_SIZE ? MI_HUGE_BLOCK_SIZE : bsize);
+  mi_page_t*  page = mi_slice_to_page(slice);
+  mi_assert_internal(mi_page_block_size(page) == bsize);
+
+  // set slice back pointers for the first MI_MAX_SLICE_OFFSET entries
+  size_t extra = slice_count-1;
+  if (extra > MI_MAX_SLICE_OFFSET) extra = MI_MAX_SLICE_OFFSET;
+  if (slice_index + extra >= segment->slice_entries) extra = segment->slice_entries - slice_index - 1;  // huge objects may have more slices than avaiable entries in the segment->slices
+
+  mi_slice_t* slice_next = slice + 1;
+  for (size_t i = 1; i <= extra; i++, slice_next++) {
+    slice_next->slice_offset = (uint32_t)(sizeof(mi_slice_t)*i);
+    slice_next->slice_count = 0;
+    slice_next->xblock_size = 1;
+  }
+
+  // and also for the last one (if not set already) (the last one is needed for coalescing and for large alignments)
+  // note: the cast is needed for ubsan since the index can be larger than MI_SLICES_PER_SEGMENT for huge allocations (see #543)
+  mi_slice_t* last = slice + slice_count - 1;
+  mi_slice_t* end = (mi_slice_t*)mi_segment_slices_end(segment);
+  if (last > end) last = end;
+  if (last > slice) {
+    last->slice_offset = (uint32_t)(sizeof(mi_slice_t) * (last - slice));
+    last->slice_count = 0;
+    last->xblock_size = 1;
+  }
+
+  // and initialize the page
+  page->is_committed = true;
+  segment->used++;
+  return page;
+}
+
+static void mi_segment_slice_split(mi_segment_t* segment, mi_slice_t* slice, size_t slice_count, mi_segments_tld_t* tld) {
+  mi_assert_internal(_mi_ptr_segment(slice) == segment);
+  mi_assert_internal(slice->slice_count >= slice_count);
+  mi_assert_internal(slice->xblock_size > 0); // no more in free queue
+  if (slice->slice_count <= slice_count) return;
+  mi_assert_internal(segment->kind != MI_SEGMENT_HUGE);
+  size_t next_index = mi_slice_index(slice) + slice_count;
+  size_t next_count = slice->slice_count - slice_count;
+  mi_segment_span_free(segment, next_index, next_count, false /* don't purge left-over part */, tld);
+  slice->slice_count = (uint32_t)slice_count;
+}
+
+static mi_page_t* mi_segments_page_find_and_allocate(size_t slice_count, mi_arena_id_t req_arena_id, mi_segments_tld_t* tld) {
+  mi_assert_internal(slice_count*MI_SEGMENT_SLICE_SIZE <= MI_LARGE_OBJ_SIZE_MAX);
+  // search from best fit up
+  mi_span_queue_t* sq = mi_span_queue_for(slice_count, tld);
+  if (slice_count == 0) slice_count = 1;
+  while (sq <= &tld->spans[MI_SEGMENT_BIN_MAX]) {
+    for (mi_slice_t* slice = sq->first; slice != NULL; slice = slice->next) {
+      if (slice->slice_count >= slice_count) {
+	// found one
+	mi_segment_t* segment = _mi_ptr_segment(slice);
+	if (_mi_arena_memid_is_suitable(segment->memid, req_arena_id)) {
+	  // found a suitable page span
+	  mi_span_queue_delete(sq, slice);
+
+	  if (slice->slice_count > slice_count) {
+	    mi_segment_slice_split(segment, slice, slice_count, tld);
+	  }
+	  mi_assert_internal(slice != NULL && slice->slice_count == slice_count && slice->xblock_size > 0);
+	  mi_page_t* page = mi_segment_span_allocate(segment, mi_slice_index(slice), slice->slice_count, tld);
+	  if (page == NULL) {
+	    // commit failed; return NULL but first restore the slice
+	    mi_segment_span_free_coalesce(slice, tld);
+	    return NULL;
+	  }
+	  return page;
+	}
+      }
+    }
+    sq++;
+  }
+  // could not find a page..
+  return NULL;
+}
+
+
+/* -----------------------------------------------------------
+   Segment allocation
+----------------------------------------------------------- */
+
+static mi_segment_t* mi_segment_os_alloc( size_t required, size_t page_alignment, bool eager_delayed, mi_arena_id_t req_arena_id,
+					  size_t* psegment_slices, size_t* ppre_size, size_t* pinfo_slices,
+					  bool commit, mi_segments_tld_t* tld, mi_os_tld_t* os_tld)
+
+{
+  mi_memid_t memid;
+  bool   allow_large = (!eager_delayed && (MI_SECURE == 0)); // only allow large OS pages once we are no longer lazy
+  size_t align_offset = 0;
+  size_t alignment = MI_SEGMENT_ALIGN;
+
+  if (page_alignment > 0) {
+    // mi_assert_internal(huge_page != NULL);
+    mi_assert_internal(page_alignment >= MI_SEGMENT_ALIGN);
+    alignment = page_alignment;
+    const size_t info_size = (*pinfo_slices) * MI_SEGMENT_SLICE_SIZE;
+    align_offset = _mi_align_up( info_size, MI_SEGMENT_ALIGN );
+    const size_t extra = align_offset - info_size;
+    // recalculate due to potential guard pages
+    *psegment_slices = mi_segment_calculate_slices(required + extra, ppre_size, pinfo_slices);
+  }
+
+  const size_t segment_size = (*psegment_slices) * MI_SEGMENT_SLICE_SIZE;
+  mi_segment_t* segment = (mi_segment_t*)_mi_arena_alloc_aligned(segment_size, alignment, align_offset, commit, allow_large, req_arena_id, &memid, os_tld);
+  if (segment == NULL) {
+    return NULL;  // failed to allocate
+  }
+
+  // ensure metadata part of the segment is committed
+  mi_commit_mask_t commit_mask;
+  if (memid.initially_committed) {
+    mi_commit_mask_create_full(&commit_mask);
+  }
+  else {
+    // at least commit the info slices
+    const size_t commit_needed = _mi_divide_up((*pinfo_slices)*MI_SEGMENT_SLICE_SIZE, MI_COMMIT_SIZE);
+    mi_assert_internal(commit_needed>0);
+    mi_commit_mask_create(0, commit_needed, &commit_mask);
+    mi_assert_internal(commit_needed*MI_COMMIT_SIZE >= (*pinfo_slices)*MI_SEGMENT_SLICE_SIZE);
+    if (!_mi_os_commit(segment, commit_needed*MI_COMMIT_SIZE, NULL, tld->stats)) {
+      _mi_arena_free(segment,segment_size,0,memid,tld->stats);
+      return NULL;
+    }
+  }
+  mi_assert_internal(segment != NULL && (uintptr_t)segment % MI_SEGMENT_SIZE == 0);
+
+  segment->memid = memid;
+  segment->allow_decommit = !memid.is_pinned;
+  segment->allow_purge = segment->allow_decommit && (mi_option_get(mi_option_purge_delay) >= 0);
+  segment->segment_size = segment_size;
+  segment->commit_mask = commit_mask;
+  segment->purge_expire = 0;
+  mi_commit_mask_create_empty(&segment->purge_mask);
+  mi_atomic_store_ptr_release(mi_segment_t, &segment->abandoned_next, NULL);  // tsan
+
+  mi_segments_track_size((long)(segment_size), tld);
+  _mi_segment_map_allocated_at(segment);
+  return segment;
+}
+
+
+// Allocate a segment from the OS aligned to `MI_SEGMENT_SIZE` .
+static mi_segment_t* mi_segment_alloc(size_t required, size_t page_alignment, mi_arena_id_t req_arena_id, mi_segments_tld_t* tld, mi_os_tld_t* os_tld, mi_page_t** huge_page)
+{
+  mi_assert_internal((required==0 && huge_page==NULL) || (required>0 && huge_page != NULL));
+
+  // calculate needed sizes first
+  size_t info_slices;
+  size_t pre_size;
+  size_t segment_slices = mi_segment_calculate_slices(required, &pre_size, &info_slices);
+
+  // Commit eagerly only if not the first N lazy segments (to reduce impact of many threads that allocate just a little)
+  const bool eager_delay = (// !_mi_os_has_overcommit() &&             // never delay on overcommit systems
+			    _mi_current_thread_count() > 1 &&       // do not delay for the first N threads
+			    tld->count < (size_t)mi_option_get(mi_option_eager_commit_delay));
+  const bool eager = !eager_delay && mi_option_is_enabled(mi_option_eager_commit);
+  bool commit = eager || (required > 0);
+
+  // Allocate the segment from the OS
+  mi_segment_t* segment = mi_segment_os_alloc(required, page_alignment, eager_delay, req_arena_id,
+					      &segment_slices, &pre_size, &info_slices, commit, tld, os_tld);
+  if (segment == NULL) return NULL;
+
+  // zero the segment info? -- not always needed as it may be zero initialized from the OS
+  if (!segment->memid.initially_zero) {
+    ptrdiff_t ofs    = offsetof(mi_segment_t, next);
+    size_t    prefix = offsetof(mi_segment_t, slices) - ofs;
+    size_t    zsize  = prefix + (sizeof(mi_slice_t) * (segment_slices + 1)); // one more
+    _mi_memzero((uint8_t*)segment + ofs, zsize);
+  }
+
+  // initialize the rest of the segment info
+  const size_t slice_entries = (segment_slices > MI_SLICES_PER_SEGMENT ? MI_SLICES_PER_SEGMENT : segment_slices);
+  segment->segment_slices = segment_slices;
+  segment->segment_info_slices = info_slices;
+  segment->thread_id = _mi_thread_id();
+  segment->cookie = _mi_ptr_cookie(segment);
+  segment->slice_entries = slice_entries;
+  segment->kind = (required == 0 ? MI_SEGMENT_NORMAL : MI_SEGMENT_HUGE);
+
+  // _mi_memzero(segment->slices, sizeof(mi_slice_t)*(info_slices+1));
+  _mi_stat_increase(&tld->stats->page_committed, mi_segment_info_size(segment));
+
+  // set up guard pages
+  size_t guard_slices = 0;
+  if (MI_SECURE>0) {
+    // in secure mode, we set up a protected page in between the segment info
+    // and the page data, and at the end of the segment.
+    size_t os_pagesize = _mi_os_page_size();
+    mi_assert_internal(mi_segment_info_size(segment) - os_pagesize >= pre_size);
+    _mi_os_protect((uint8_t*)segment + mi_segment_info_size(segment) - os_pagesize, os_pagesize);
+    uint8_t* end = (uint8_t*)segment + mi_segment_size(segment) - os_pagesize;
+    mi_segment_ensure_committed(segment, end, os_pagesize, tld->stats);
+    _mi_os_protect(end, os_pagesize);
+    if (slice_entries == segment_slices) segment->slice_entries--; // don't use the last slice :-(
+    guard_slices = 1;
+  }
+
+  // reserve first slices for segment info
+  mi_page_t* page0 = mi_segment_span_allocate(segment, 0, info_slices, tld);
+  mi_assert_internal(page0!=NULL); if (page0==NULL) return NULL; // cannot fail as we always commit in advance
+  mi_assert_internal(segment->used == 1);
+  segment->used = 0; // don't count our internal slices towards usage
+
+  // initialize initial free pages
+  if (segment->kind == MI_SEGMENT_NORMAL) { // not a huge page
+    mi_assert_internal(huge_page==NULL);
+    mi_segment_span_free(segment, info_slices, segment->slice_entries - info_slices, false /* don't purge */, tld);
+  }
+  else {
+    mi_assert_internal(huge_page!=NULL);
+    mi_assert_internal(mi_commit_mask_is_empty(&segment->purge_mask));
+    mi_assert_internal(mi_commit_mask_is_full(&segment->commit_mask));
+    *huge_page = mi_segment_span_allocate(segment, info_slices, segment_slices - info_slices - guard_slices, tld);
+    mi_assert_internal(*huge_page != NULL); // cannot fail as we commit in advance
+  }
+
+  mi_assert_expensive(mi_segment_is_valid(segment,tld));
+  return segment;
+}
+
+
+static void mi_segment_free(mi_segment_t* segment, bool force, mi_segments_tld_t* tld) {
+  MI_UNUSED(force);
+  mi_assert_internal(segment != NULL);
+  mi_assert_internal(segment->next == NULL);
+  mi_assert_internal(segment->used == 0);
+
+  // Remove the free pages
+  mi_slice_t* slice = &segment->slices[0];
+  const mi_slice_t* end = mi_segment_slices_end(segment);
+  #if MI_DEBUG>1
+  size_t page_count = 0;
+  #endif
+  while (slice < end) {
+    mi_assert_internal(slice->slice_count > 0);
+    mi_assert_internal(slice->slice_offset == 0);
+    mi_assert_internal(mi_slice_index(slice)==0 || slice->xblock_size == 0); // no more used pages ..
+    if (slice->xblock_size == 0 && segment->kind != MI_SEGMENT_HUGE) {
+      mi_segment_span_remove_from_queue(slice, tld);
+    }
+    #if MI_DEBUG>1
+    page_count++;
+    #endif
+    slice = slice + slice->slice_count;
+  }
+  mi_assert_internal(page_count == 2); // first page is allocated by the segment itself
+
+  // stats
+  _mi_stat_decrease(&tld->stats->page_committed, mi_segment_info_size(segment));
+
+  // return it to the OS
+  mi_segment_os_free(segment, tld);
+}
+
+
+/* -----------------------------------------------------------
+   Page Free
+----------------------------------------------------------- */
+
+static void mi_segment_abandon(mi_segment_t* segment, mi_segments_tld_t* tld);
+
+// note: can be called on abandoned pages
+static mi_slice_t* mi_segment_page_clear(mi_page_t* page, mi_segments_tld_t* tld) {
+  mi_assert_internal(page->xblock_size > 0);
+  mi_assert_internal(mi_page_all_free(page));
+  mi_segment_t* segment = _mi_ptr_segment(page);
+  mi_assert_internal(segment->used > 0);
+
+  size_t inuse = page->capacity * mi_page_block_size(page);
+  _mi_stat_decrease(&tld->stats->page_committed, inuse);
+  _mi_stat_decrease(&tld->stats->pages, 1);
+
+  // reset the page memory to reduce memory pressure?
+  if (segment->allow_decommit && mi_option_is_enabled(mi_option_deprecated_page_reset)) {
+    size_t psize;
+    uint8_t* start = _mi_page_start(segment, page, &psize);
+    _mi_os_reset(start, psize, tld->stats);
+  }
+
+  // zero the page data, but not the segment fields
+  page->is_zero_init = false;
+  ptrdiff_t ofs = offsetof(mi_page_t, capacity);
+  _mi_memzero((uint8_t*)page + ofs, sizeof(*page) - ofs);
+  page->xblock_size = 1;
+
+  // and free it
+  mi_slice_t* slice = mi_segment_span_free_coalesce(mi_page_to_slice(page), tld);
+  segment->used--;
+  // cannot assert segment valid as it is called during reclaim
+  // mi_assert_expensive(mi_segment_is_valid(segment, tld));
+  return slice;
+}
+
+void _mi_segment_page_free(mi_page_t* page, bool force, mi_segments_tld_t* tld)
+{
+  mi_assert(page != NULL);
+
+  mi_segment_t* segment = _mi_page_segment(page);
+  mi_assert_expensive(mi_segment_is_valid(segment,tld));
+
+  // mark it as free now
+  mi_segment_page_clear(page, tld);
+  mi_assert_expensive(mi_segment_is_valid(segment, tld));
+
+  if (segment->used == 0) {
+    // no more used pages; remove from the free list and free the segment
+    mi_segment_free(segment, force, tld);
+  }
+  else if (segment->used == segment->abandoned) {
+    // only abandoned pages; remove from free list and abandon
+    mi_segment_abandon(segment,tld);
+  }
+}
+
+
+/* -----------------------------------------------------------
+Abandonment
+
+When threads terminate, they can leave segments with
+live blocks (reachable through other threads). Such segments
+are "abandoned" and will be reclaimed by other threads to
+reuse their pages and/or free them eventually
+
+We maintain a global list of abandoned segments that are
+reclaimed on demand. Since this is shared among threads
+the implementation needs to avoid the A-B-A problem on
+popping abandoned segments: <https://en.wikipedia.org/wiki/ABA_problem>
+We use tagged pointers to avoid accidentally identifying
+reused segments, much like stamped references in Java.
+Secondly, we maintain a reader counter to avoid resetting
+or decommitting segments that have a pending read operation.
+
+Note: the current implementation is one possible design;
+another way might be to keep track of abandoned segments
+in the arenas/segment_cache's. This would have the advantage of keeping
+all concurrent code in one place and not needing to deal
+with ABA issues. The drawback is that it is unclear how to
+scan abandoned segments efficiently in that case as they
+would be spread among all other segments in the arenas.
+----------------------------------------------------------- */
+
+// Use the bottom 20-bits (on 64-bit) of the aligned segment pointers
+// to put in a tag that increments on update to avoid the A-B-A problem.
+#define MI_TAGGED_MASK   MI_SEGMENT_MASK
+typedef uintptr_t        mi_tagged_segment_t;
+
+static mi_segment_t* mi_tagged_segment_ptr(mi_tagged_segment_t ts) {
+  return (mi_segment_t*)(ts & ~MI_TAGGED_MASK);
+}
+
+static mi_tagged_segment_t mi_tagged_segment(mi_segment_t* segment, mi_tagged_segment_t ts) {
+  mi_assert_internal(((uintptr_t)segment & MI_TAGGED_MASK) == 0);
+  uintptr_t tag = ((ts & MI_TAGGED_MASK) + 1) & MI_TAGGED_MASK;
+  return ((uintptr_t)segment | tag);
+}
+
+// This is a list of visited abandoned pages that were full at the time.
+// this list migrates to `abandoned` when that becomes NULL. The use of
+// this list reduces contention and the rate at which segments are visited.
+static mi_decl_cache_align _Atomic(mi_segment_t*)       abandoned_visited; // = NULL
+
+// The abandoned page list (tagged as it supports pop)
+static mi_decl_cache_align _Atomic(mi_tagged_segment_t) abandoned;         // = NULL
+
+// Maintain these for debug purposes (these counts may be a bit off)
+static mi_decl_cache_align _Atomic(size_t)           abandoned_count;
+static mi_decl_cache_align _Atomic(size_t)           abandoned_visited_count;
+
+// We also maintain a count of current readers of the abandoned list
+// in order to prevent resetting/decommitting segment memory if it might
+// still be read.
+static mi_decl_cache_align _Atomic(size_t)           abandoned_readers; // = 0
+
+// Push on the visited list
+static void mi_abandoned_visited_push(mi_segment_t* segment) {
+  mi_assert_internal(segment->thread_id == 0);
+  mi_assert_internal(mi_atomic_load_ptr_relaxed(mi_segment_t,&segment->abandoned_next) == NULL);
+  mi_assert_internal(segment->next == NULL);
+  mi_assert_internal(segment->used > 0);
+  mi_segment_t* anext = mi_atomic_load_ptr_relaxed(mi_segment_t, &abandoned_visited);
+  do {
+    mi_atomic_store_ptr_release(mi_segment_t, &segment->abandoned_next, anext);
+  } while (!mi_atomic_cas_ptr_weak_release(mi_segment_t, &abandoned_visited, &anext, segment));
+  mi_atomic_increment_relaxed(&abandoned_visited_count);
+}
+
+// Move the visited list to the abandoned list.
+static bool mi_abandoned_visited_revisit(void)
+{
+  // quick check if the visited list is empty
+  if (mi_atomic_load_ptr_relaxed(mi_segment_t, &abandoned_visited) == NULL) return false;
+
+  // grab the whole visited list
+  mi_segment_t* first = mi_atomic_exchange_ptr_acq_rel(mi_segment_t, &abandoned_visited, NULL);
+  if (first == NULL) return false;
+
+  // first try to swap directly if the abandoned list happens to be NULL
+  mi_tagged_segment_t afirst;
+  mi_tagged_segment_t ts = mi_atomic_load_relaxed(&abandoned);
+  if (mi_tagged_segment_ptr(ts)==NULL) {
+    size_t count = mi_atomic_load_relaxed(&abandoned_visited_count);
+    afirst = mi_tagged_segment(first, ts);
+    if (mi_atomic_cas_strong_acq_rel(&abandoned, &ts, afirst)) {
+      mi_atomic_add_relaxed(&abandoned_count, count);
+      mi_atomic_sub_relaxed(&abandoned_visited_count, count);
+      return true;
+    }
+  }
+
+  // find the last element of the visited list: O(n)
+  mi_segment_t* last = first;
+  mi_segment_t* next;
+  while ((next = mi_atomic_load_ptr_relaxed(mi_segment_t, &last->abandoned_next)) != NULL) {
+    last = next;
+  }
+
+  // and atomically prepend to the abandoned list
+  // (no need to increase the readers as we don't access the abandoned segments)
+  mi_tagged_segment_t anext = mi_atomic_load_relaxed(&abandoned);
+  size_t count;
+  do {
+    count = mi_atomic_load_relaxed(&abandoned_visited_count);
+    mi_atomic_store_ptr_release(mi_segment_t, &last->abandoned_next, mi_tagged_segment_ptr(anext));
+    afirst = mi_tagged_segment(first, anext);
+  } while (!mi_atomic_cas_weak_release(&abandoned, &anext, afirst));
+  mi_atomic_add_relaxed(&abandoned_count, count);
+  mi_atomic_sub_relaxed(&abandoned_visited_count, count);
+  return true;
+}
+
+// Push on the abandoned list.
+static void mi_abandoned_push(mi_segment_t* segment) {
+  mi_assert_internal(segment->thread_id == 0);
+  mi_assert_internal(mi_atomic_load_ptr_relaxed(mi_segment_t, &segment->abandoned_next) == NULL);
+  mi_assert_internal(segment->next == NULL);
+  mi_assert_internal(segment->used > 0);
+  mi_tagged_segment_t next;
+  mi_tagged_segment_t ts = mi_atomic_load_relaxed(&abandoned);
+  do {
+    mi_atomic_store_ptr_release(mi_segment_t, &segment->abandoned_next, mi_tagged_segment_ptr(ts));
+    next = mi_tagged_segment(segment, ts);
+  } while (!mi_atomic_cas_weak_release(&abandoned, &ts, next));
+  mi_atomic_increment_relaxed(&abandoned_count);
+}
+
+// Wait until there are no more pending reads on segments that used to be in the abandoned list
+// called for example from `arena.c` before decommitting
+void _mi_abandoned_await_readers(void) {
+  size_t n;
+  do {
+    n = mi_atomic_load_acquire(&abandoned_readers);
+    if (n != 0) mi_atomic_yield();
+  } while (n != 0);
+}
+
+// Pop from the abandoned list
+static mi_segment_t* mi_abandoned_pop(void) {
+  mi_segment_t* segment;
+  // Check efficiently if it is empty (or if the visited list needs to be moved)
+  mi_tagged_segment_t ts = mi_atomic_load_relaxed(&abandoned);
+  segment = mi_tagged_segment_ptr(ts);
+  if mi_likely(segment == NULL) {
+    if mi_likely(!mi_abandoned_visited_revisit()) { // try to swap in the visited list on NULL
+      return NULL;
+    }
+  }
+
+  // Do a pop. We use a reader count to prevent
+  // a segment to be decommitted while a read is still pending,
+  // and a tagged pointer to prevent A-B-A link corruption.
+  // (this is called from `region.c:_mi_mem_free` for example)
+  mi_atomic_increment_relaxed(&abandoned_readers);  // ensure no segment gets decommitted
+  mi_tagged_segment_t next = 0;
+  ts = mi_atomic_load_acquire(&abandoned);
+  do {
+    segment = mi_tagged_segment_ptr(ts);
+    if (segment != NULL) {
+      mi_segment_t* anext = mi_atomic_load_ptr_relaxed(mi_segment_t, &segment->abandoned_next);
+      next = mi_tagged_segment(anext, ts); // note: reads the segment's `abandoned_next` field so should not be decommitted
+    }
+  } while (segment != NULL && !mi_atomic_cas_weak_acq_rel(&abandoned, &ts, next));
+  mi_atomic_decrement_relaxed(&abandoned_readers);  // release reader lock
+  if (segment != NULL) {
+    mi_atomic_store_ptr_release(mi_segment_t, &segment->abandoned_next, NULL);
+    mi_atomic_decrement_relaxed(&abandoned_count);
+  }
+  return segment;
+}
+
+/* -----------------------------------------------------------
+   Abandon segment/page
+----------------------------------------------------------- */
+
+static void mi_segment_abandon(mi_segment_t* segment, mi_segments_tld_t* tld) {
+  mi_assert_internal(segment->used == segment->abandoned);
+  mi_assert_internal(segment->used > 0);
+  mi_assert_internal(mi_atomic_load_ptr_relaxed(mi_segment_t, &segment->abandoned_next) == NULL);
+  mi_assert_internal(segment->abandoned_visits == 0);
+  mi_assert_expensive(mi_segment_is_valid(segment,tld));
+
+  // remove the free pages from the free page queues
+  mi_slice_t* slice = &segment->slices[0];
+  const mi_slice_t* end = mi_segment_slices_end(segment);
+  while (slice < end) {
+    mi_assert_internal(slice->slice_count > 0);
+    mi_assert_internal(slice->slice_offset == 0);
+    if (slice->xblock_size == 0) { // a free page
+      mi_segment_span_remove_from_queue(slice,tld);
+      slice->xblock_size = 0; // but keep it free
+    }
+    slice = slice + slice->slice_count;
+  }
+
+  // perform delayed decommits (forcing is much slower on mstress)
+  mi_segment_try_purge(segment, mi_option_is_enabled(mi_option_abandoned_page_purge) /* force? */, tld->stats);
+
+  // all pages in the segment are abandoned; add it to the abandoned list
+  _mi_stat_increase(&tld->stats->segments_abandoned, 1);
+  mi_segments_track_size(-((long)mi_segment_size(segment)), tld);
+  segment->thread_id = 0;
+  mi_atomic_store_ptr_release(mi_segment_t, &segment->abandoned_next, NULL);
+  segment->abandoned_visits = 1;   // from 0 to 1 to signify it is abandoned
+  mi_abandoned_push(segment);
+}
+
+void _mi_segment_page_abandon(mi_page_t* page, mi_segments_tld_t* tld) {
+  mi_assert(page != NULL);
+  mi_assert_internal(mi_page_thread_free_flag(page)==MI_NEVER_DELAYED_FREE);
+  mi_assert_internal(mi_page_heap(page) == NULL);
+  mi_segment_t* segment = _mi_page_segment(page);
+
+  mi_assert_expensive(mi_segment_is_valid(segment,tld));
+  segment->abandoned++;
+
+  _mi_stat_increase(&tld->stats->pages_abandoned, 1);
+  mi_assert_internal(segment->abandoned <= segment->used);
+  if (segment->used == segment->abandoned) {
+    // all pages are abandoned, abandon the entire segment
+    mi_segment_abandon(segment, tld);
+  }
+}
+
+/* -----------------------------------------------------------
+  Reclaim abandoned pages
+----------------------------------------------------------- */
+
+static mi_slice_t* mi_slices_start_iterate(mi_segment_t* segment, const mi_slice_t** end) {
+  mi_slice_t* slice = &segment->slices[0];
+  *end = mi_segment_slices_end(segment);
+  mi_assert_internal(slice->slice_count>0 && slice->xblock_size>0); // segment allocated page
+  slice = slice + slice->slice_count; // skip the first segment allocated page
+  return slice;
+}
+
+// Possibly free pages and check if free space is available
+static bool mi_segment_check_free(mi_segment_t* segment, size_t slices_needed, size_t block_size, mi_segments_tld_t* tld)
+{
+  mi_assert_internal(block_size < MI_HUGE_BLOCK_SIZE);
+  mi_assert_internal(mi_segment_is_abandoned(segment));
+  bool has_page = false;
+
+  // for all slices
+  const mi_slice_t* end;
+  mi_slice_t* slice = mi_slices_start_iterate(segment, &end);
+  while (slice < end) {
+    mi_assert_internal(slice->slice_count > 0);
+    mi_assert_internal(slice->slice_offset == 0);
+    if (mi_slice_is_used(slice)) { // used page
+      // ensure used count is up to date and collect potential concurrent frees
+      mi_page_t* const page = mi_slice_to_page(slice);
+      _mi_page_free_collect(page, false);
+      if (mi_page_all_free(page)) {
+	// if this page is all free now, free it without adding to any queues (yet)
+	mi_assert_internal(page->next == NULL && page->prev==NULL);
+	_mi_stat_decrease(&tld->stats->pages_abandoned, 1);
+	segment->abandoned--;
+	slice = mi_segment_page_clear(page, tld); // re-assign slice due to coalesce!
+	mi_assert_internal(!mi_slice_is_used(slice));
+	if (slice->slice_count >= slices_needed) {
+	  has_page = true;
+	}
+      }
+      else {
+	if (page->xblock_size == block_size && mi_page_has_any_available(page)) {
+	  // a page has available free blocks of the right size
+	  has_page = true;
+	}
+      }
+    }
+    else {
+      // empty span
+      if (slice->slice_count >= slices_needed) {
+	has_page = true;
+      }
+    }
+    slice = slice + slice->slice_count;
+  }
+  return has_page;
+}
+
+// Reclaim an abandoned segment; returns NULL if the segment was freed
+// set `right_page_reclaimed` to `true` if it reclaimed a page of the right `block_size` that was not full.
+static mi_segment_t* mi_segment_reclaim(mi_segment_t* segment, mi_heap_t* heap, size_t requested_block_size, bool* right_page_reclaimed, mi_segments_tld_t* tld) {
+  mi_assert_internal(mi_atomic_load_ptr_relaxed(mi_segment_t, &segment->abandoned_next) == NULL);
+  mi_assert_expensive(mi_segment_is_valid(segment, tld));
+  if (right_page_reclaimed != NULL) { *right_page_reclaimed = false; }
+
+  segment->thread_id = _mi_thread_id();
+  segment->abandoned_visits = 0;
+  mi_segments_track_size((long)mi_segment_size(segment), tld);
+  mi_assert_internal(segment->next == NULL);
+  _mi_stat_decrease(&tld->stats->segments_abandoned, 1);
+
+  // for all slices
+  const mi_slice_t* end;
+  mi_slice_t* slice = mi_slices_start_iterate(segment, &end);
+  while (slice < end) {
+    mi_assert_internal(slice->slice_count > 0);
+    mi_assert_internal(slice->slice_offset == 0);
+    if (mi_slice_is_used(slice)) {
+      // in use: reclaim the page in our heap
+      mi_page_t* page = mi_slice_to_page(slice);
+      mi_assert_internal(page->is_committed);
+      mi_assert_internal(mi_page_thread_free_flag(page)==MI_NEVER_DELAYED_FREE);
+      mi_assert_internal(mi_page_heap(page) == NULL);
+      mi_assert_internal(page->next == NULL && page->prev==NULL);
+      _mi_stat_decrease(&tld->stats->pages_abandoned, 1);
+      segment->abandoned--;
+      // set the heap again and allow delayed free again
+      mi_page_set_heap(page, heap);
+      _mi_page_use_delayed_free(page, MI_USE_DELAYED_FREE, true); // override never (after heap is set)
+      _mi_page_free_collect(page, false); // ensure used count is up to date
+      if (mi_page_all_free(page)) {
+	// if everything free by now, free the page
+	slice = mi_segment_page_clear(page, tld);   // set slice again due to coalesceing
+      }
+      else {
+	// otherwise reclaim it into the heap
+	_mi_page_reclaim(heap, page);
+	if (requested_block_size == page->xblock_size && mi_page_has_any_available(page)) {
+	  if (right_page_reclaimed != NULL) { *right_page_reclaimed = true; }
+	}
+      }
+    }
+    else {
+      // the span is free, add it to our page queues
+      slice = mi_segment_span_free_coalesce(slice, tld); // set slice again due to coalesceing
+    }
+    mi_assert_internal(slice->slice_count>0 && slice->slice_offset==0);
+    slice = slice + slice->slice_count;
+  }
+
+  mi_assert(segment->abandoned == 0);
+  if (segment->used == 0) {  // due to page_clear
+    mi_assert_internal(right_page_reclaimed == NULL || !(*right_page_reclaimed));
+    mi_segment_free(segment, false, tld);
+    return NULL;
+  }
+  else {
+    return segment;
+  }
+}
+
+
+void _mi_abandoned_reclaim_all(mi_heap_t* heap, mi_segments_tld_t* tld) {
+  mi_segment_t* segment;
+  while ((segment = mi_abandoned_pop()) != NULL) {
+    mi_segment_reclaim(segment, heap, 0, NULL, tld);
+  }
+}
+
+static mi_segment_t* mi_segment_try_reclaim(mi_heap_t* heap, size_t needed_slices, size_t block_size, bool* reclaimed, mi_segments_tld_t* tld)
+{
+  *reclaimed = false;
+  mi_segment_t* segment;
+  long max_tries = mi_option_get_clamp(mi_option_max_segment_reclaim, 8, 1024);     // limit the work to bound allocation times
+  while ((max_tries-- > 0) && ((segment = mi_abandoned_pop()) != NULL)) {
+    segment->abandoned_visits++;
+    // todo: an arena exclusive heap will potentially visit many abandoned unsuitable segments
+    // and push them into the visited list and use many tries. Perhaps we can skip non-suitable ones in a better way?
+    bool is_suitable = _mi_heap_memid_is_suitable(heap, segment->memid);
+    bool has_page = mi_segment_check_free(segment,needed_slices,block_size,tld); // try to free up pages (due to concurrent frees)
+    if (segment->used == 0) {
+      // free the segment (by forced reclaim) to make it available to other threads.
+      // note1: we prefer to free a segment as that might lead to reclaiming another
+      // segment that is still partially used.
+      // note2: we could in principle optimize this by skipping reclaim and directly
+      // freeing but that would violate some invariants temporarily)
+      mi_segment_reclaim(segment, heap, 0, NULL, tld);
+    }
+    else if (has_page && is_suitable) {
+      // found a large enough free span, or a page of the right block_size with free space
+      // we return the result of reclaim (which is usually `segment`) as it might free
+      // the segment due to concurrent frees (in which case `NULL` is returned).
+      return mi_segment_reclaim(segment, heap, block_size, reclaimed, tld);
+    }
+    else if (segment->abandoned_visits > 3 && is_suitable) {
+      // always reclaim on 3rd visit to limit the abandoned queue length.
+      mi_segment_reclaim(segment, heap, 0, NULL, tld);
+    }
+    else {
+      // otherwise, push on the visited list so it gets not looked at too quickly again
+      mi_segment_try_purge(segment, true /* force? */, tld->stats); // force purge if needed as we may not visit soon again
+      mi_abandoned_visited_push(segment);
+    }
+  }
+  return NULL;
+}
+
+
+void _mi_abandoned_collect(mi_heap_t* heap, bool force, mi_segments_tld_t* tld)
+{
+  mi_segment_t* segment;
+  int max_tries = (force ? 16*1024 : 1024); // limit latency
+  if (force) {
+    mi_abandoned_visited_revisit();
+  }
+  while ((max_tries-- > 0) && ((segment = mi_abandoned_pop()) != NULL)) {
+    mi_segment_check_free(segment,0,0,tld); // try to free up pages (due to concurrent frees)
+    if (segment->used == 0) {
+      // free the segment (by forced reclaim) to make it available to other threads.
+      // note: we could in principle optimize this by skipping reclaim and directly
+      // freeing but that would violate some invariants temporarily)
+      mi_segment_reclaim(segment, heap, 0, NULL, tld);
+    }
+    else {
+      // otherwise, purge if needed and push on the visited list
+      // note: forced purge can be expensive if many threads are destroyed/created as in mstress.
+      mi_segment_try_purge(segment, force, tld->stats);
+      mi_abandoned_visited_push(segment);
+    }
+  }
+}
+
+/* -----------------------------------------------------------
+   Reclaim or allocate
+----------------------------------------------------------- */
+
+static mi_segment_t* mi_segment_reclaim_or_alloc(mi_heap_t* heap, size_t needed_slices, size_t block_size, mi_segments_tld_t* tld, mi_os_tld_t* os_tld)
+{
+  mi_assert_internal(block_size < MI_HUGE_BLOCK_SIZE);
+  mi_assert_internal(block_size <= MI_LARGE_OBJ_SIZE_MAX);
+
+  // 1. try to reclaim an abandoned segment
+  bool reclaimed;
+  mi_segment_t* segment = mi_segment_try_reclaim(heap, needed_slices, block_size, &reclaimed, tld);
+  if (reclaimed) {
+    // reclaimed the right page right into the heap
+    mi_assert_internal(segment != NULL);
+    return NULL; // pretend out-of-memory as the page will be in the page queue of the heap with available blocks
+  }
+  else if (segment != NULL) {
+    // reclaimed a segment with a large enough empty span in it
+    return segment;
+  }
+  // 2. otherwise allocate a fresh segment
+  return mi_segment_alloc(0, 0, heap->arena_id, tld, os_tld, NULL);
+}
+
+
+/* -----------------------------------------------------------
+   Page allocation
+----------------------------------------------------------- */
+
+static mi_page_t* mi_segments_page_alloc(mi_heap_t* heap, mi_page_kind_t page_kind, size_t required, size_t block_size, mi_segments_tld_t* tld, mi_os_tld_t* os_tld)
+{
+  mi_assert_internal(required <= MI_LARGE_OBJ_SIZE_MAX && page_kind <= MI_PAGE_LARGE);
+
+  // find a free page
+  size_t page_size = _mi_align_up(required, (required > MI_MEDIUM_PAGE_SIZE ? MI_MEDIUM_PAGE_SIZE : MI_SEGMENT_SLICE_SIZE));
+  size_t slices_needed = page_size / MI_SEGMENT_SLICE_SIZE;
+  mi_assert_internal(slices_needed * MI_SEGMENT_SLICE_SIZE == page_size);
+  mi_page_t* page = mi_segments_page_find_and_allocate(slices_needed, heap->arena_id, tld); //(required <= MI_SMALL_SIZE_MAX ? 0 : slices_needed), tld);
+  if (page==NULL) {
+    // no free page, allocate a new segment and try again
+    if (mi_segment_reclaim_or_alloc(heap, slices_needed, block_size, tld, os_tld) == NULL) {
+      // OOM or reclaimed a good page in the heap
+      return NULL;
+    }
+    else {
+      // otherwise try again
+      return mi_segments_page_alloc(heap, page_kind, required, block_size, tld, os_tld);
+    }
+  }
+  mi_assert_internal(page != NULL && page->slice_count*MI_SEGMENT_SLICE_SIZE == page_size);
+  mi_assert_internal(_mi_ptr_segment(page)->thread_id == _mi_thread_id());
+  mi_segment_try_purge(_mi_ptr_segment(page), false, tld->stats);
+  return page;
+}
+
+
+
+/* -----------------------------------------------------------
+   Huge page allocation
+----------------------------------------------------------- */
+
+static mi_page_t* mi_segment_huge_page_alloc(size_t size, size_t page_alignment, mi_arena_id_t req_arena_id, mi_segments_tld_t* tld, mi_os_tld_t* os_tld)
+{
+  mi_page_t* page = NULL;
+  mi_segment_t* segment = mi_segment_alloc(size,page_alignment,req_arena_id,tld,os_tld,&page);
+  if (segment == NULL || page==NULL) return NULL;
+  mi_assert_internal(segment->used==1);
+  mi_assert_internal(mi_page_block_size(page) >= size);
+  #if MI_HUGE_PAGE_ABANDON
+  segment->thread_id = 0; // huge segments are immediately abandoned
+  #endif
+
+  // for huge pages we initialize the xblock_size as we may
+  // overallocate to accommodate large alignments.
+  size_t psize;
+  uint8_t* start = _mi_segment_page_start(segment, page, &psize);
+  page->xblock_size = (psize > MI_HUGE_BLOCK_SIZE ? MI_HUGE_BLOCK_SIZE : (uint32_t)psize);
+
+  // decommit the part of the prefix of a page that will not be used; this can be quite large (close to MI_SEGMENT_SIZE)
+  if (page_alignment > 0 && segment->allow_decommit) {
+    uint8_t* aligned_p = (uint8_t*)_mi_align_up((uintptr_t)start, page_alignment);
+    mi_assert_internal(_mi_is_aligned(aligned_p, page_alignment));
+    mi_assert_internal(psize - (aligned_p - start) >= size);
+    uint8_t* decommit_start = start + sizeof(mi_block_t);              // for the free list
+    ptrdiff_t decommit_size = aligned_p - decommit_start;
+    _mi_os_reset(decommit_start, decommit_size, &_mi_stats_main);   // note: cannot use segment_decommit on huge segments
+  }
+
+  return page;
+}
+
+#if MI_HUGE_PAGE_ABANDON
+// free huge block from another thread
+void _mi_segment_huge_page_free(mi_segment_t* segment, mi_page_t* page, mi_block_t* block) {
+  // huge page segments are always abandoned and can be freed immediately by any thread
+  mi_assert_internal(segment->kind==MI_SEGMENT_HUGE);
+  mi_assert_internal(segment == _mi_page_segment(page));
+  mi_assert_internal(mi_atomic_load_relaxed(&segment->thread_id)==0);
+
+  // claim it and free
+  mi_heap_t* heap = mi_heap_get_default(); // issue #221; don't use the internal get_default_heap as we need to ensure the thread is initialized.
+  // paranoia: if this it the last reference, the cas should always succeed
+  size_t expected_tid = 0;
+  if (mi_atomic_cas_strong_acq_rel(&segment->thread_id, &expected_tid, heap->thread_id)) {
+    mi_block_set_next(page, block, page->free);
+    page->free = block;
+    page->used--;
+    page->is_zero = false;
+    mi_assert(page->used == 0);
+    mi_tld_t* tld = heap->tld;
+    _mi_segment_page_free(page, true, &tld->segments);
+  }
+#if (MI_DEBUG!=0)
+  else {
+    mi_assert_internal(false);
+  }
+#endif
+}
+
+#else
+// reset memory of a huge block from another thread
+void _mi_segment_huge_page_reset(mi_segment_t* segment, mi_page_t* page, mi_block_t* block) {
+  MI_UNUSED(page);
+  mi_assert_internal(segment->kind == MI_SEGMENT_HUGE);
+  mi_assert_internal(segment == _mi_page_segment(page));
+  mi_assert_internal(page->used == 1); // this is called just before the free
+  mi_assert_internal(page->free == NULL);
+  if (segment->allow_decommit) {
+    size_t csize = mi_usable_size(block);
+    if (csize > sizeof(mi_block_t)) {
+      csize = csize - sizeof(mi_block_t);
+      uint8_t* p = (uint8_t*)block + sizeof(mi_block_t);
+      _mi_os_reset(p, csize, &_mi_stats_main);  // note: cannot use segment_decommit on huge segments
+    }
+  }
+}
+#endif
+
+/* -----------------------------------------------------------
+   Page allocation and free
+----------------------------------------------------------- */
+mi_page_t* _mi_segment_page_alloc(mi_heap_t* heap, size_t block_size, size_t page_alignment, mi_segments_tld_t* tld, mi_os_tld_t* os_tld) {
+  mi_page_t* page;
+  if mi_unlikely(page_alignment > MI_ALIGNMENT_MAX) {
+    mi_assert_internal(_mi_is_power_of_two(page_alignment));
+    mi_assert_internal(page_alignment >= MI_SEGMENT_SIZE);
+    if (page_alignment < MI_SEGMENT_SIZE) { page_alignment = MI_SEGMENT_SIZE; }
+    page = mi_segment_huge_page_alloc(block_size,page_alignment,heap->arena_id,tld,os_tld);
+  }
+  else if (block_size <= MI_SMALL_OBJ_SIZE_MAX) {
+    page = mi_segments_page_alloc(heap,MI_PAGE_SMALL,block_size,block_size,tld,os_tld);
+  }
+  else if (block_size <= MI_MEDIUM_OBJ_SIZE_MAX) {
+    page = mi_segments_page_alloc(heap,MI_PAGE_MEDIUM,MI_MEDIUM_PAGE_SIZE,block_size,tld, os_tld);
+  }
+  else if (block_size <= MI_LARGE_OBJ_SIZE_MAX) {
+    page = mi_segments_page_alloc(heap,MI_PAGE_LARGE,block_size,block_size,tld, os_tld);
+  }
+  else {
+    page = mi_segment_huge_page_alloc(block_size,page_alignment,heap->arena_id,tld,os_tld);
+  }
+  mi_assert_internal(page == NULL || _mi_heap_memid_is_suitable(heap, _mi_page_segment(page)->memid));
+  mi_assert_expensive(page == NULL || mi_segment_is_valid(_mi_page_segment(page),tld));
+  return page;
+}
diff --git a/compat/mimalloc/stats.c b/compat/mimalloc/stats.c
new file mode 100644
index 00000000000000..6817e07aa1ee9f
--- /dev/null
+++ b/compat/mimalloc/stats.c
@@ -0,0 +1,467 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2018-2021, Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+#include "mimalloc.h"
+#include "mimalloc/internal.h"
+#include "mimalloc/atomic.h"
+#include "mimalloc/prim.h"
+
+#include <stdio.h>  // snprintf
+#include <string.h> // memset
+
+#if defined(_MSC_VER) && (_MSC_VER < 1920)
+#pragma warning(disable:4204)  // non-constant aggregate initializer
+#endif
+
+/* -----------------------------------------------------------
+  Statistics operations
+----------------------------------------------------------- */
+
+static bool mi_is_in_main(void* stat) {
+  return ((uint8_t*)stat >= (uint8_t*)&_mi_stats_main
+	 && (uint8_t*)stat < ((uint8_t*)&_mi_stats_main + sizeof(mi_stats_t)));
+}
+
+static void mi_stat_update(mi_stat_count_t* stat, int64_t amount) {
+  if (amount == 0) return;
+  if (mi_is_in_main(stat))
+  {
+    // add atomically (for abandoned pages)
+    int64_t current = mi_atomic_addi64_relaxed(&stat->current, amount);
+    mi_atomic_maxi64_relaxed(&stat->peak, current + amount);
+    if (amount > 0) {
+      mi_atomic_addi64_relaxed(&stat->allocated,amount);
+    }
+    else {
+      mi_atomic_addi64_relaxed(&stat->freed, -amount);
+    }
+  }
+  else {
+    // add thread local
+    stat->current += amount;
+    if (stat->current > stat->peak) stat->peak = stat->current;
+    if (amount > 0) {
+      stat->allocated += amount;
+    }
+    else {
+      stat->freed += -amount;
+    }
+  }
+}
+
+void _mi_stat_counter_increase(mi_stat_counter_t* stat, size_t amount) {
+  if (mi_is_in_main(stat)) {
+    mi_atomic_addi64_relaxed( &stat->count, 1 );
+    mi_atomic_addi64_relaxed( &stat->total, (int64_t)amount );
+  }
+  else {
+    stat->count++;
+    stat->total += amount;
+  }
+}
+
+void _mi_stat_increase(mi_stat_count_t* stat, size_t amount) {
+  mi_stat_update(stat, (int64_t)amount);
+}
+
+void _mi_stat_decrease(mi_stat_count_t* stat, size_t amount) {
+  mi_stat_update(stat, -((int64_t)amount));
+}
+
+// must be thread safe as it is called from stats_merge
+static void mi_stat_add(mi_stat_count_t* stat, const mi_stat_count_t* src, int64_t unit) {
+  if (stat==src) return;
+  if (src->allocated==0 && src->freed==0) return;
+  mi_atomic_addi64_relaxed( &stat->allocated, src->allocated * unit);
+  mi_atomic_addi64_relaxed( &stat->current, src->current * unit);
+  mi_atomic_addi64_relaxed( &stat->freed, src->freed * unit);
+  // peak scores do not work across threads..
+  mi_atomic_addi64_relaxed( &stat->peak, src->peak * unit);
+}
+
+static void mi_stat_counter_add(mi_stat_counter_t* stat, const mi_stat_counter_t* src, int64_t unit) {
+  if (stat==src) return;
+  mi_atomic_addi64_relaxed( &stat->total, src->total * unit);
+  mi_atomic_addi64_relaxed( &stat->count, src->count * unit);
+}
+
+// must be thread safe as it is called from stats_merge
+static void mi_stats_add(mi_stats_t* stats, const mi_stats_t* src) {
+  if (stats==src) return;
+  mi_stat_add(&stats->segments, &src->segments,1);
+  mi_stat_add(&stats->pages, &src->pages,1);
+  mi_stat_add(&stats->reserved, &src->reserved, 1);
+  mi_stat_add(&stats->committed, &src->committed, 1);
+  mi_stat_add(&stats->reset, &src->reset, 1);
+  mi_stat_add(&stats->purged, &src->purged, 1);
+  mi_stat_add(&stats->page_committed, &src->page_committed, 1);
+
+  mi_stat_add(&stats->pages_abandoned, &src->pages_abandoned, 1);
+  mi_stat_add(&stats->segments_abandoned, &src->segments_abandoned, 1);
+  mi_stat_add(&stats->threads, &src->threads, 1);
+
+  mi_stat_add(&stats->malloc, &src->malloc, 1);
+  mi_stat_add(&stats->segments_cache, &src->segments_cache, 1);
+  mi_stat_add(&stats->normal, &src->normal, 1);
+  mi_stat_add(&stats->huge, &src->huge, 1);
+  mi_stat_add(&stats->large, &src->large, 1);
+
+  mi_stat_counter_add(&stats->pages_extended, &src->pages_extended, 1);
+  mi_stat_counter_add(&stats->mmap_calls, &src->mmap_calls, 1);
+  mi_stat_counter_add(&stats->commit_calls, &src->commit_calls, 1);
+  mi_stat_counter_add(&stats->reset_calls, &src->reset_calls, 1);
+  mi_stat_counter_add(&stats->purge_calls, &src->purge_calls, 1);
+
+  mi_stat_counter_add(&stats->page_no_retire, &src->page_no_retire, 1);
+  mi_stat_counter_add(&stats->searches, &src->searches, 1);
+  mi_stat_counter_add(&stats->normal_count, &src->normal_count, 1);
+  mi_stat_counter_add(&stats->huge_count, &src->huge_count, 1);
+  mi_stat_counter_add(&stats->large_count, &src->large_count, 1);
+#if MI_STAT>1
+  for (size_t i = 0; i <= MI_BIN_HUGE; i++) {
+    if (src->normal_bins[i].allocated > 0 || src->normal_bins[i].freed > 0) {
+      mi_stat_add(&stats->normal_bins[i], &src->normal_bins[i], 1);
+    }
+  }
+#endif
+}
+
+/* -----------------------------------------------------------
+  Display statistics
+----------------------------------------------------------- */
+
+// unit > 0 : size in binary bytes
+// unit == 0: count as decimal
+// unit < 0 : count in binary
+static void mi_printf_amount(int64_t n, int64_t unit, mi_output_fun* out, void* arg, const char* fmt) {
+  char buf[32]; buf[0] = 0;
+  int  len = 32;
+  const char* suffix = (unit <= 0 ? " " : "B");
+  const int64_t base = (unit == 0 ? 1000 : 1024);
+  if (unit>0) n *= unit;
+
+  const int64_t pos = (n < 0 ? -n : n);
+  if (pos < base) {
+    if (n!=1 || suffix[0] != 'B') {  // skip printing 1 B for the unit column
+      snprintf(buf, len, "%d   %-3s", (int)n, (n==0 ? "" : suffix));
+    }
+  }
+  else {
+    int64_t divider = base;
+    const char* magnitude = "K";
+    if (pos >= divider*base) { divider *= base; magnitude = "M"; }
+    if (pos >= divider*base) { divider *= base; magnitude = "G"; }
+    const int64_t tens = (n / (divider/10));
+    const long whole = (long)(tens/10);
+    const long frac1 = (long)(tens%10);
+    char unitdesc[8];
+    snprintf(unitdesc, 8, "%s%s%s", magnitude, (base==1024 ? "i" : ""), suffix);
+    snprintf(buf, len, "%ld.%ld %-3s", whole, (frac1 < 0 ? -frac1 : frac1), unitdesc);
+  }
+  _mi_fprintf(out, arg, (fmt==NULL ? "%12s" : fmt), buf);
+}
+
+
+static void mi_print_amount(int64_t n, int64_t unit, mi_output_fun* out, void* arg) {
+  mi_printf_amount(n,unit,out,arg,NULL);
+}
+
+static void mi_print_count(int64_t n, int64_t unit, mi_output_fun* out, void* arg) {
+  if (unit==1) _mi_fprintf(out, arg, "%12s"," ");
+	  else mi_print_amount(n,0,out,arg);
+}
+
+static void mi_stat_print_ex(const mi_stat_count_t* stat, const char* msg, int64_t unit, mi_output_fun* out, void* arg, const char* notok ) {
+  _mi_fprintf(out, arg,"%10s:", msg);
+  if (unit > 0) {
+    mi_print_amount(stat->peak, unit, out, arg);
+    mi_print_amount(stat->allocated, unit, out, arg);
+    mi_print_amount(stat->freed, unit, out, arg);
+    mi_print_amount(stat->current, unit, out, arg);
+    mi_print_amount(unit, 1, out, arg);
+    mi_print_count(stat->allocated, unit, out, arg);
+    if (stat->allocated > stat->freed) {
+      _mi_fprintf(out, arg, "  ");
+      _mi_fprintf(out, arg, (notok == NULL ? "not all freed" : notok));
+      _mi_fprintf(out, arg, "\n");
+    }
+    else {
+      _mi_fprintf(out, arg, "  ok\n");
+    }
+  }
+  else if (unit<0) {
+    mi_print_amount(stat->peak, -1, out, arg);
+    mi_print_amount(stat->allocated, -1, out, arg);
+    mi_print_amount(stat->freed, -1, out, arg);
+    mi_print_amount(stat->current, -1, out, arg);
+    if (unit==-1) {
+      _mi_fprintf(out, arg, "%24s", "");
+    }
+    else {
+      mi_print_amount(-unit, 1, out, arg);
+      mi_print_count((stat->allocated / -unit), 0, out, arg);
+    }
+    if (stat->allocated > stat->freed)
+      _mi_fprintf(out, arg, "  not all freed!\n");
+    else
+      _mi_fprintf(out, arg, "  ok\n");
+  }
+  else {
+    mi_print_amount(stat->peak, 1, out, arg);
+    mi_print_amount(stat->allocated, 1, out, arg);
+    _mi_fprintf(out, arg, "%11s", " ");  // no freed
+    mi_print_amount(stat->current, 1, out, arg);
+    _mi_fprintf(out, arg, "\n");
+  }
+}
+
+static void mi_stat_print(const mi_stat_count_t* stat, const char* msg, int64_t unit, mi_output_fun* out, void* arg) {
+  mi_stat_print_ex(stat, msg, unit, out, arg, NULL);
+}
+
+static void mi_stat_peak_print(const mi_stat_count_t* stat, const char* msg, int64_t unit, mi_output_fun* out, void* arg) {
+  _mi_fprintf(out, arg, "%10s:", msg);
+  mi_print_amount(stat->peak, unit, out, arg);
+  _mi_fprintf(out, arg, "\n");
+}
+
+static void mi_stat_counter_print(const mi_stat_counter_t* stat, const char* msg, mi_output_fun* out, void* arg ) {
+  _mi_fprintf(out, arg, "%10s:", msg);
+  mi_print_amount(stat->total, -1, out, arg);
+  _mi_fprintf(out, arg, "\n");
+}
+
+
+static void mi_stat_counter_print_avg(const mi_stat_counter_t* stat, const char* msg, mi_output_fun* out, void* arg) {
+  const int64_t avg_tens = (stat->count == 0 ? 0 : (stat->total*10 / stat->count));
+  const long avg_whole = (long)(avg_tens/10);
+  const long avg_frac1 = (long)(avg_tens%10);
+  _mi_fprintf(out, arg, "%10s: %5ld.%ld avg\n", msg, avg_whole, avg_frac1);
+}
+
+
+static void mi_print_header(mi_output_fun* out, void* arg ) {
+  _mi_fprintf(out, arg, "%10s: %11s %11s %11s %11s %11s %11s\n", "heap stats", "peak   ", "total   ", "freed   ", "current   ", "unit   ", "count   ");
+}
+
+#if MI_STAT>1
+static void mi_stats_print_bins(const mi_stat_count_t* bins, size_t max, const char* fmt, mi_output_fun* out, void* arg) {
+  bool found = false;
+  char buf[64];
+  for (size_t i = 0; i <= max; i++) {
+    if (bins[i].allocated > 0) {
+      found = true;
+      int64_t unit = _mi_bin_size((uint8_t)i);
+      snprintf(buf, 64, "%s %3lu", fmt, (long)i);
+      mi_stat_print(&bins[i], buf, unit, out, arg);
+    }
+  }
+  if (found) {
+    _mi_fprintf(out, arg, "\n");
+    mi_print_header(out, arg);
+  }
+}
+#endif
+
+
+
+//------------------------------------------------------------
+// Use an output wrapper for line-buffered output
+// (which is nice when using loggers etc.)
+//------------------------------------------------------------
+typedef struct buffered_s {
+  mi_output_fun* out;   // original output function
+  void*          arg;   // and state
+  char*          buf;   // local buffer of at least size `count+1`
+  size_t         used;  // currently used chars `used <= count`
+  size_t         count; // total chars available for output
+} buffered_t;
+
+static void mi_buffered_flush(buffered_t* buf) {
+  buf->buf[buf->used] = 0;
+  _mi_fputs(buf->out, buf->arg, NULL, buf->buf);
+  buf->used = 0;
+}
+
+static void mi_cdecl mi_buffered_out(const char* msg, void* arg) {
+  buffered_t* buf = (buffered_t*)arg;
+  if (msg==NULL || buf==NULL) return;
+  for (const char* src = msg; *src != 0; src++) {
+    char c = *src;
+    if (buf->used >= buf->count) mi_buffered_flush(buf);
+    mi_assert_internal(buf->used < buf->count);
+    buf->buf[buf->used++] = c;
+    if (c == '\n') mi_buffered_flush(buf);
+  }
+}
+
+//------------------------------------------------------------
+// Print statistics
+//------------------------------------------------------------
+
+static void _mi_stats_print(mi_stats_t* stats, mi_output_fun* out0, void* arg0) mi_attr_noexcept {
+  // wrap the output function to be line buffered
+  char buf[256];
+  buffered_t buffer = { out0, arg0, NULL, 0, 255 };
+  buffer.buf = buf;
+  mi_output_fun* out = &mi_buffered_out;
+  void* arg = &buffer;
+
+  // and print using that
+  mi_print_header(out,arg);
+  #if MI_STAT>1
+  mi_stats_print_bins(stats->normal_bins, MI_BIN_HUGE, "normal",out,arg);
+  #endif
+  #if MI_STAT
+  mi_stat_print(&stats->normal, "normal", (stats->normal_count.count == 0 ? 1 : -(stats->normal.allocated / stats->normal_count.count)), out, arg);
+  mi_stat_print(&stats->large, "large", (stats->large_count.count == 0 ? 1 : -(stats->large.allocated / stats->large_count.count)), out, arg);
+  mi_stat_print(&stats->huge, "huge", (stats->huge_count.count == 0 ? 1 : -(stats->huge.allocated / stats->huge_count.count)), out, arg);
+  mi_stat_count_t total = { 0,0,0,0 };
+  mi_stat_add(&total, &stats->normal, 1);
+  mi_stat_add(&total, &stats->large, 1);
+  mi_stat_add(&total, &stats->huge, 1);
+  mi_stat_print(&total, "total", 1, out, arg);
+  #endif
+  #if MI_STAT>1
+  mi_stat_print(&stats->malloc, "malloc req", 1, out, arg);
+  _mi_fprintf(out, arg, "\n");
+  #endif
+  mi_stat_print_ex(&stats->reserved, "reserved", 1, out, arg, "");
+  mi_stat_print_ex(&stats->committed, "committed", 1, out, arg, "");
+  mi_stat_peak_print(&stats->reset, "reset", 1, out, arg );
+  mi_stat_peak_print(&stats->purged, "purged", 1, out, arg );
+  mi_stat_print(&stats->page_committed, "touched", 1, out, arg);
+  mi_stat_print(&stats->segments, "segments", -1, out, arg);
+  mi_stat_print(&stats->segments_abandoned, "-abandoned", -1, out, arg);
+  mi_stat_print(&stats->segments_cache, "-cached", -1, out, arg);
+  mi_stat_print(&stats->pages, "pages", -1, out, arg);
+  mi_stat_print(&stats->pages_abandoned, "-abandoned", -1, out, arg);
+  mi_stat_counter_print(&stats->pages_extended, "-extended", out, arg);
+  mi_stat_counter_print(&stats->page_no_retire, "-noretire", out, arg);
+  mi_stat_counter_print(&stats->mmap_calls, "mmaps", out, arg);
+  mi_stat_counter_print(&stats->commit_calls, "commits", out, arg);
+  mi_stat_counter_print(&stats->reset_calls, "resets", out, arg);
+  mi_stat_counter_print(&stats->purge_calls, "purges", out, arg);
+  mi_stat_print(&stats->threads, "threads", -1, out, arg);
+  mi_stat_counter_print_avg(&stats->searches, "searches", out, arg);
+  _mi_fprintf(out, arg, "%10s: %5zu\n", "numa nodes", _mi_os_numa_node_count());
+
+  size_t elapsed;
+  size_t user_time;
+  size_t sys_time;
+  size_t current_rss;
+  size_t peak_rss;
+  size_t current_commit;
+  size_t peak_commit;
+  size_t page_faults;
+  mi_process_info(&elapsed, &user_time, &sys_time, &current_rss, &peak_rss, &current_commit, &peak_commit, &page_faults);
+  _mi_fprintf(out, arg, "%10s: %5ld.%03ld s\n", "elapsed", elapsed/1000, elapsed%1000);
+  _mi_fprintf(out, arg, "%10s: user: %ld.%03ld s, system: %ld.%03ld s, faults: %lu, rss: ", "process",
+	      user_time/1000, user_time%1000, sys_time/1000, sys_time%1000, (unsigned long)page_faults );
+  mi_printf_amount((int64_t)peak_rss, 1, out, arg, "%s");
+  if (peak_commit > 0) {
+    _mi_fprintf(out, arg, ", commit: ");
+    mi_printf_amount((int64_t)peak_commit, 1, out, arg, "%s");
+  }
+  _mi_fprintf(out, arg, "\n");
+}
+
+static mi_msecs_t mi_process_start; // = 0
+
+static mi_stats_t* mi_stats_get_default(void) {
+  mi_heap_t* heap = mi_heap_get_default();
+  return &heap->tld->stats;
+}
+
+static void mi_stats_merge_from(mi_stats_t* stats) {
+  if (stats != &_mi_stats_main) {
+    mi_stats_add(&_mi_stats_main, stats);
+    memset(stats, 0, sizeof(mi_stats_t));
+  }
+}
+
+void mi_stats_reset(void) mi_attr_noexcept {
+  mi_stats_t* stats = mi_stats_get_default();
+  if (stats != &_mi_stats_main) { memset(stats, 0, sizeof(mi_stats_t)); }
+  memset(&_mi_stats_main, 0, sizeof(mi_stats_t));
+  if (mi_process_start == 0) { mi_process_start = _mi_clock_start(); };
+}
+
+void mi_stats_merge(void) mi_attr_noexcept {
+  mi_stats_merge_from( mi_stats_get_default() );
+}
+
+void _mi_stats_done(mi_stats_t* stats) {  // called from `mi_thread_done`
+  mi_stats_merge_from(stats);
+}
+
+void mi_stats_print_out(mi_output_fun* out, void* arg) mi_attr_noexcept {
+  mi_stats_merge_from(mi_stats_get_default());
+  _mi_stats_print(&_mi_stats_main, out, arg);
+}
+
+void mi_stats_print(void* out) mi_attr_noexcept {
+  // for compatibility there is an `out` parameter (which can be `stdout` or `stderr`)
+  mi_stats_print_out((mi_output_fun*)out, NULL);
+}
+
+void mi_thread_stats_print_out(mi_output_fun* out, void* arg) mi_attr_noexcept {
+  _mi_stats_print(mi_stats_get_default(), out, arg);
+}
+
+
+// ----------------------------------------------------------------
+// Basic timer for convenience; use milli-seconds to avoid doubles
+// ----------------------------------------------------------------
+
+static mi_msecs_t mi_clock_diff;
+
+mi_msecs_t _mi_clock_now(void) {
+  return _mi_prim_clock_now();
+}
+
+mi_msecs_t _mi_clock_start(void) {
+  if (mi_clock_diff == 0.0) {
+    mi_msecs_t t0 = _mi_clock_now();
+    mi_clock_diff = _mi_clock_now() - t0;
+  }
+  return _mi_clock_now();
+}
+
+mi_msecs_t _mi_clock_end(mi_msecs_t start) {
+  mi_msecs_t end = _mi_clock_now();
+  return (end - start - mi_clock_diff);
+}
+
+
+// --------------------------------------------------------
+// Basic process statistics
+// --------------------------------------------------------
+
+mi_decl_export void mi_process_info(size_t* elapsed_msecs, size_t* user_msecs, size_t* system_msecs, size_t* current_rss, size_t* peak_rss, size_t* current_commit, size_t* peak_commit, size_t* page_faults) mi_attr_noexcept
+{
+  mi_process_info_t pinfo;
+  _mi_memzero_var(pinfo);
+  pinfo.elapsed        = _mi_clock_end(mi_process_start);
+  pinfo.current_commit = (size_t)(mi_atomic_loadi64_relaxed((_Atomic(int64_t)*)&_mi_stats_main.committed.current));
+  pinfo.peak_commit    = (size_t)(mi_atomic_loadi64_relaxed((_Atomic(int64_t)*)&_mi_stats_main.committed.peak));
+  pinfo.current_rss    = pinfo.current_commit;
+  pinfo.peak_rss       = pinfo.peak_commit;
+  pinfo.utime          = 0;
+  pinfo.stime          = 0;
+  pinfo.page_faults    = 0;
+
+  _mi_prim_process_info(&pinfo);
+
+  if (elapsed_msecs!=NULL)  *elapsed_msecs  = (pinfo.elapsed < 0 ? 0 : (pinfo.elapsed < (mi_msecs_t)PTRDIFF_MAX ? (size_t)pinfo.elapsed : PTRDIFF_MAX));
+  if (user_msecs!=NULL)     *user_msecs     = (pinfo.utime < 0 ? 0 : (pinfo.utime < (mi_msecs_t)PTRDIFF_MAX ? (size_t)pinfo.utime : PTRDIFF_MAX));
+  if (system_msecs!=NULL)   *system_msecs   = (pinfo.stime < 0 ? 0 : (pinfo.stime < (mi_msecs_t)PTRDIFF_MAX ? (size_t)pinfo.stime : PTRDIFF_MAX));
+  if (current_rss!=NULL)    *current_rss    = pinfo.current_rss;
+  if (peak_rss!=NULL)       *peak_rss       = pinfo.peak_rss;
+  if (current_commit!=NULL) *current_commit = pinfo.current_commit;
+  if (peak_commit!=NULL)    *peak_commit    = pinfo.peak_commit;
+  if (page_faults!=NULL)    *page_faults    = pinfo.page_faults;
+}

From b9c4eb2a71a9cddd563a71b7425238aa2fe903ac Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 24 Jun 2019 23:41:27 +0200
Subject: [PATCH 032/259] mimalloc: adjust for building inside Git

We want to compile mimalloc's source code as part of Git, rather than
requiring the code to be built as an external library: mimalloc uses a
CMake-based build, which is not necessarily easy to integrate into the
flavors of Git for Windows (which will be the main benefitting port).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mimalloc/alloc.c    | 4 ----
 compat/mimalloc/mimalloc.h | 3 ++-
 2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/compat/mimalloc/alloc.c b/compat/mimalloc/alloc.c
index 961f6d53d0f2c7..ae272c1fb54504 100644
--- a/compat/mimalloc/alloc.c
+++ b/compat/mimalloc/alloc.c
@@ -16,10 +16,6 @@ terms of the MIT license. A copy of the license can be found in the file
 #include <string.h>      // memset, strlen (for mi_strdup)
 #include <stdlib.h>      // malloc, abort
 
-#define MI_IN_ALLOC_C
-#include "alloc-override.c"
-#undef MI_IN_ALLOC_C
-
 // ------------------------------------------------------
 // Allocation
 // ------------------------------------------------------
diff --git a/compat/mimalloc/mimalloc.h b/compat/mimalloc/mimalloc.h
index c0f5e96e51e975..7e3b5dd66e91a0 100644
--- a/compat/mimalloc/mimalloc.h
+++ b/compat/mimalloc/mimalloc.h
@@ -95,7 +95,8 @@ terms of the MIT license. A copy of the license can be found in the file
 // Includes
 // ------------------------------------------------------
 
-#include <stddef.h>     // size_t
+#include "git-compat-util.h"
+
 #include <stdbool.h>    // bool
 #include <stdint.h>     // INTPTR_MAX
 

From d5ee8ff407ba920b34c3e6572688e2cdb7dabda7 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 24 Jun 2019 23:43:06 +0200
Subject: [PATCH 033/259] mimalloc: offer a build-time option to enable it

By defining `USE_MIMALLOC`, Git can now be compiled with that
nicely-fast and small allocator.

Note that we have to disable a couple `DEVELOPER` options to build
mimalloc's source code, as it makes heavy use of declarations after
statements, among other things that disagree with Git's conventions.

We even have to silence some GCC warnings in non-DEVELOPER mode. For
example, the `-Wno-array-bounds` flag is needed because in `-O2` builds,
trying to call `NtCurrentTeb()` (which `_mi_thread_id()` does on
Windows) causes the bogus warning about a system header, likely related
to https://sourceforge.net/p/mingw-w64/mailman/message/37674519/ and to
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99578:

C:/git-sdk-64-minimal/mingw64/include/psdk_inc/intrin-impl.h:838:1:
        error: array subscript 0 is outside array bounds of 'long long unsigned int[0]' [-Werror=array-bounds]
  838 | __buildreadseg(__readgsqword, unsigned __int64, "gs", "q")
      | ^~~~~~~~~~~~~~

Also: The `mimalloc` library uses C11-style atomics, therefore we must
require that standard when compiling with GCC if we want to use
`mimalloc` (instead of requiring "only" C99). This is what we do in the
CMake definition already, therefore this commit does not need to touch
`contrib/buildsystems/`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 Makefile          | 37 +++++++++++++++++++++++++++++++++++++
 config.mak.dev    |  2 ++
 config.mak.uname  |  2 +-
 git-compat-util.h | 10 ++++++++++
 4 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index db48c72620c78d..600f7380e70127 100644
--- a/Makefile
+++ b/Makefile
@@ -2072,6 +2072,43 @@ ifdef USE_NED_ALLOCATOR
 	OVERRIDE_STRDUP = YesPlease
 endif
 
+ifdef USE_MIMALLOC
+	MIMALLOC_OBJS = \
+		compat/mimalloc/alloc-aligned.o \
+		compat/mimalloc/alloc.o \
+		compat/mimalloc/arena.o \
+		compat/mimalloc/bitmap.o \
+		compat/mimalloc/heap.o \
+		compat/mimalloc/init.o \
+		compat/mimalloc/options.o \
+		compat/mimalloc/os.o \
+		compat/mimalloc/page.o \
+		compat/mimalloc/random.o \
+		compat/mimalloc/prim/windows/prim.o \
+		compat/mimalloc/segment.o \
+		compat/mimalloc/segment-cache.o \
+		compat/mimalloc/segment-map.o \
+		compat/mimalloc/stats.o
+
+	COMPAT_CFLAGS += -Icompat/mimalloc -DMI_DEBUG=0 -DUSE_MIMALLOC --std=gnu11
+	COMPAT_OBJS += $(MIMALLOC_OBJS)
+
+$(MIMALLOC_OBJS): COMPAT_CFLAGS += -DBANNED_H
+
+$(MIMALLOC_OBJS): COMPAT_CFLAGS += \
+	-Wno-attributes \
+	-Wno-unknown-pragmas \
+	-Wno-array-bounds
+
+ifdef DEVELOPER
+$(MIMALLOC_OBJS): COMPAT_CFLAGS += \
+	-Wno-pedantic \
+	-Wno-declaration-after-statement \
+	-Wno-old-style-definition \
+	-Wno-missing-prototypes
+endif
+endif
+
 ifdef OVERRIDE_STRDUP
 	COMPAT_CFLAGS += -DOVERRIDE_STRDUP
 	COMPAT_OBJS += compat/strdup.o
diff --git a/config.mak.dev b/config.mak.dev
index 5229c3548451b7..56b2a581475160 100644
--- a/config.mak.dev
+++ b/config.mak.dev
@@ -22,8 +22,10 @@ endif
 
 ifneq ($(uname_S),FreeBSD)
 ifneq ($(or $(filter gcc6,$(COMPILER_FEATURES)),$(filter clang7,$(COMPILER_FEATURES))),)
+ifndef USE_MIMALLOC
 DEVELOPER_CFLAGS += -std=gnu99
 endif
+endif
 else
 # FreeBSD cannot limit to C99 because its system headers unconditionally
 # rely on C11 features.
diff --git a/config.mak.uname b/config.mak.uname
index d59f01a562ed36..1102ee11a76a8b 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -495,7 +495,7 @@ endif
 	CC = compat/vcbuild/scripts/clink.pl
 	AR = compat/vcbuild/scripts/lib.pl
 	CFLAGS =
-	BASIC_CFLAGS = -nologo -I. -Icompat/vcbuild/include -DWIN32 -D_CONSOLE -DHAVE_STRING_H -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_DEPRECATE
+	BASIC_CFLAGS = -nologo -I. -Icompat/vcbuild/include -DWIN32 -D_CONSOLE -DHAVE_STRING_H -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_DEPRECATE -MP -std:c11
 	COMPAT_OBJS = compat/msvc.o compat/winansi.o \
 		compat/win32/flush.o \
 		compat/win32/path-utils.o \
diff --git a/git-compat-util.h b/git-compat-util.h
index 468d40498fd35a..4fc80210ede16f 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -420,6 +420,16 @@ char *gitdirname(char *);
 # include <sys/sysinfo.h>
 #endif
 
+#ifdef USE_MIMALLOC
+#include "mimalloc.h"
+#define malloc mi_malloc
+#define calloc mi_calloc
+#define realloc mi_realloc
+#define free mi_free
+#define strdup mi_strdup
+#define strndup mi_strndup
+#endif
+
 /* On most systems <netdb.h> would have given us this, but
  * not on some systems (e.g. z/OS).
  */

From 4530a6bf49c4ec7fb890c1249d439704c57e1bc0 Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhostetler@github.com>
Date: Fri, 12 May 2023 15:54:11 -0400
Subject: [PATCH 034/259] mimalloc: use "weak" random seed when statically
 linked

Always use the internal "use_weak" random seed when initializing
the "mimalloc" heap when statically linked on Windows.

The imported "mimalloc" routines support several random sources
to seed the heap data structures, including BCrypt.dll and
RtlGenRandom.  Crashes have been reported when using BCrypt.dll
if it initialized during an `atexit()` handler function.  Granted,
such DLL initialization should not happen in an atexit handler,
but yet the crashes remain.

It should be noted that on Windows when statically linked, the
mimalloc startup code (called by the GCC CRT to initialize static
data prior to calling `main()`) always uses the internal "weak"
random seed.  "mimalloc" does not try to load an alternate
random source until after the OS initialization has completed.

Heap data is stored in `__declspec(thread)` TLS data and in theory
each Git thread will have its own heap data.  However, testing
shows that the "mimalloc" library doesn't actually call
`os_random_buf()` (to load a new random source) when creating these
new per-thread heap structures.

However, if an atexit handler is forced to run on a non-main
thread, the "mimalloc" library *WILL* try to create a new heap
and seed it with `os_random_buf()`.  (The reason for this is still
a mystery to this author.)  The `os_random_buf()` call can cause
the (previously uninitialized BCrypt.dll library) to be dynamically
loaded and a call made into it.  Crashes have been reported in
v2.40.1.vfs.0.0 while in this call.

As a workaround, the fix here forces the use of the internal
"use_weak" random code for the subsequent `os_random_buf()` calls.
Since we have been using that random generator for the majority
of the program, it seems safe to use it for the final few mallocs
in the atexit handler (of which there really shouldn't be that many.

Signed-off-by: Jeff Hostetler <jeffhostetler@github.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mimalloc/init.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/compat/mimalloc/init.c b/compat/mimalloc/init.c
index 4670d5510db187..4ec5812e3ce1d0 100644
--- a/compat/mimalloc/init.c
+++ b/compat/mimalloc/init.c
@@ -302,7 +302,11 @@ static bool _mi_heap_init(void) {
     _mi_memcpy_aligned(tld, &tld_empty, sizeof(*tld));
     _mi_memcpy_aligned(heap, &_mi_heap_empty, sizeof(*heap));
     heap->thread_id = _mi_thread_id();
+    #if defined(_WIN32) && !defined(MI_SHARED_LIB)
+    _mi_random_init_weak(&heap->random); // match mi_heap_main_init()
+    #else
     _mi_random_init(&heap->random);
+    #endif
     heap->cookie  = _mi_heap_random_next(heap) | 1;
     heap->keys[0] = _mi_heap_random_next(heap);
     heap->keys[1] = _mi_heap_random_next(heap);

From 721eec29a811423a0f4730f0bd56db0c09553523 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 24 Jun 2019 23:45:21 +0200
Subject: [PATCH 035/259] mingw: use mimalloc

Thorough benchmarking with repacking a subset of linux.git (the commit
history reachable from 93a6fefe2f ([PATCH] fix the SYSCTL=n compilation,
2007-02-28), to be precise) suggest that this allocator is on par, in
multi-threaded situations maybe even better than nedmalloc:

`git repack -adfq` with mimalloc, 8 threads:

31.166991900 27.576763800 28.712311000 27.373859000 27.163141900

`git repack -adfq` with nedmalloc, 8 threads:

31.915032900 27.149883100 28.244933700 27.240188800 28.580849500

In a different test using GitHub Actions build agents (probably
single-threaded, a core-strength of nedmalloc)):

`git repack -q -d -l -A --unpack-unreachable=2.weeks.ago` with mimalloc:

943.426 978.500 939.709 959.811 954.605

`git repack -q -d -l -A --unpack-unreachable=2.weeks.ago` with nedmalloc:

995.383 952.179 943.253 963.043 980.468

While these measurements were not executed with complete scientific
rigor, as no hardware was set aside specifically for these benchmarks,
it shows that mimalloc and nedmalloc perform almost the same, nedmalloc
with a bit higher variance and also slightly higher average (further
testing suggests that nedmalloc performs worse in multi-threaded
situations than in single-threaded ones).

In short: mimalloc seems to be slightly better suited for our purposes
than nedmalloc.

Seeing that mimalloc is developed actively, while nedmalloc ceased to
see any updates in eight years, let's use mimalloc on Windows instead.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 config.mak.uname | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/config.mak.uname b/config.mak.uname
index 1102ee11a76a8b..36b3943bbdee86 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -738,7 +738,7 @@ ifeq ($(uname_S),MINGW)
 	HAVE_LIBCHARSET_H = YesPlease
 	USE_GETTEXT_SCHEME = fallthrough
 	USE_LIBPCRE = YesPlease
-	USE_NED_ALLOCATOR = YesPlease
+	USE_MIMALLOC = YesPlease
 	NO_PYTHON =
         ifeq (/mingw64,$(subst 32,64,$(prefix)))
 		# Move system config into top-level /etc/

From 31160bb960bb9753429f1eac1b2a37797477ac34 Mon Sep 17 00:00:00 2001
From: Thomas Braun <thomas.braun@byte-physics.de>
Date: Thu, 8 May 2014 21:43:24 +0200
Subject: [PATCH 036/259] transport: optionally disable side-band-64k

Since commit 0c499ea60fda (send-pack: demultiplex a sideband stream with
status data, 2010-02-05) the send-pack builtin uses the side-band-64k
capability if advertised by the server.

Unfortunately this breaks pushing over the dump git protocol if used
over a network connection.

The detailed reasons for this breakage are (by courtesy of Jeff Preshing,
quoted from https://groups.google.com/d/msg/msysgit/at8D7J-h7mw/eaLujILGUWoJ):

	MinGW wraps Windows sockets in CRT file descriptors in order to
	mimic the functionality of POSIX sockets. This causes msvcrt.dll
	to treat sockets as Installable File System (IFS) handles,
	calling ReadFile, WriteFile, DuplicateHandle and CloseHandle on
	them. This approach works well in simple cases on recent
	versions of Windows, but does not support all usage patterns. In
	particular, using this approach, any attempt to read & write
	concurrently on the same socket (from one or more processes)
	will deadlock in a scenario where the read waits for a response
	from the server which is only invoked after the write. This is
	what send_pack currently attempts to do in the use_sideband
	codepath.

The new config option `sendpack.sideband` allows to override the
side-band-64k capability of the server, and thus makes the dumb git
protocol work.

Other transportation methods like ssh and http/https still benefit from
the sideband channel, therefore the default value of `sendpack.sideband`
is still true.

Signed-off-by: Thomas Braun <thomas.braun@byte-physics.de>
Signed-off-by: Oliver Schneider <oliver@assarbad.net>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 Documentation/config.txt          | 2 ++
 Documentation/config/sendpack.txt | 5 +++++
 send-pack.c                       | 6 +++---
 3 files changed, 10 insertions(+), 3 deletions(-)
 create mode 100644 Documentation/config/sendpack.txt

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 8c0b3ed8075214..3ad4956fe48944 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -518,6 +518,8 @@ include::config/safe.txt[]
 
 include::config/sendemail.txt[]
 
+include::config/sendpack.txt[]
+
 include::config/sequencer.txt[]
 
 include::config/showbranch.txt[]
diff --git a/Documentation/config/sendpack.txt b/Documentation/config/sendpack.txt
new file mode 100644
index 00000000000000..e306f657fba7dd
--- /dev/null
+++ b/Documentation/config/sendpack.txt
@@ -0,0 +1,5 @@
+sendpack.sideband::
+	Allows to disable the side-band-64k capability for send-pack even
+	when it is advertised by the server. Makes it possible to work
+	around a limitation in the git for windows implementation together
+	with the dump git protocol. Defaults to true.
diff --git a/send-pack.c b/send-pack.c
index fa2f5eec17bba1..f9e6255ee13328 100644
--- a/send-pack.c
+++ b/send-pack.c
@@ -488,7 +488,7 @@ int send_pack(struct send_pack_args *args,
 	int need_pack_data = 0;
 	int allow_deleting_refs = 0;
 	int status_report = 0;
-	int use_sideband = 0;
+	int use_sideband = 1;
 	int quiet_supported = 0;
 	int agent_supported = 0;
 	int advertise_sid = 0;
@@ -511,6 +511,7 @@ int send_pack(struct send_pack_args *args,
 		return 0;
 	}
 
+	git_config_get_bool("sendpack.sideband", &use_sideband);
 	git_config_get_bool("push.negotiate", &push_negotiate);
 	if (push_negotiate)
 		get_commons_through_negotiation(args->url, remote_refs, &commons);
@@ -529,8 +530,7 @@ int send_pack(struct send_pack_args *args,
 		allow_deleting_refs = 1;
 	if (server_supports("ofs-delta"))
 		args->use_ofs_delta = 1;
-	if (server_supports("side-band-64k"))
-		use_sideband = 1;
+	use_sideband = use_sideband && server_supports("side-band-64k");
 	if (server_supports("quiet"))
 		quiet_supported = 1;
 	if (server_supports("agent"))

From 3ba8c79559f438dd0cce5840ad9853d9b754614e Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 14 Nov 2019 20:09:23 +0100
Subject: [PATCH 037/259] mingw: make sure `errno` is set correctly when socket
 operations fail

The winsock2 library provides functions that work on different data
types than file descriptors, therefore we wrap them.

But that is not the only difference: they also do not set `errno` but
expect the callers to enquire about errors via `WSAGetLastError()`.

Let's translate that into appropriate `errno` values whenever the socket
operations fail so that Git's code base does not have to change its
expectations.

This closes https://github.com/git-for-windows/git/issues/2404

Helped-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 157 +++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 147 insertions(+), 10 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 29d3f09768c29a..40b952071e8243 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2041,18 +2041,150 @@ static void ensure_socket_initialization(void)
 	initialized = 1;
 }
 
+static int winsock_error_to_errno(DWORD err)
+{
+	switch (err) {
+	case WSAEINTR: return EINTR;
+	case WSAEBADF: return EBADF;
+	case WSAEACCES: return EACCES;
+	case WSAEFAULT: return EFAULT;
+	case WSAEINVAL: return EINVAL;
+	case WSAEMFILE: return EMFILE;
+	case WSAEWOULDBLOCK: return EWOULDBLOCK;
+	case WSAEINPROGRESS: return EINPROGRESS;
+	case WSAEALREADY: return EALREADY;
+	case WSAENOTSOCK: return ENOTSOCK;
+	case WSAEDESTADDRREQ: return EDESTADDRREQ;
+	case WSAEMSGSIZE: return EMSGSIZE;
+	case WSAEPROTOTYPE: return EPROTOTYPE;
+	case WSAENOPROTOOPT: return ENOPROTOOPT;
+	case WSAEPROTONOSUPPORT: return EPROTONOSUPPORT;
+	case WSAEOPNOTSUPP: return EOPNOTSUPP;
+	case WSAEAFNOSUPPORT: return EAFNOSUPPORT;
+	case WSAEADDRINUSE: return EADDRINUSE;
+	case WSAEADDRNOTAVAIL: return EADDRNOTAVAIL;
+	case WSAENETDOWN: return ENETDOWN;
+	case WSAENETUNREACH: return ENETUNREACH;
+	case WSAENETRESET: return ENETRESET;
+	case WSAECONNABORTED: return ECONNABORTED;
+	case WSAECONNRESET: return ECONNRESET;
+	case WSAENOBUFS: return ENOBUFS;
+	case WSAEISCONN: return EISCONN;
+	case WSAENOTCONN: return ENOTCONN;
+	case WSAETIMEDOUT: return ETIMEDOUT;
+	case WSAECONNREFUSED: return ECONNREFUSED;
+	case WSAELOOP: return ELOOP;
+	case WSAENAMETOOLONG: return ENAMETOOLONG;
+	case WSAEHOSTUNREACH: return EHOSTUNREACH;
+	case WSAENOTEMPTY: return ENOTEMPTY;
+	/* No errno equivalent; default to EIO */
+	case WSAESOCKTNOSUPPORT:
+	case WSAEPFNOSUPPORT:
+	case WSAESHUTDOWN:
+	case WSAETOOMANYREFS:
+	case WSAEHOSTDOWN:
+	case WSAEPROCLIM:
+	case WSAEUSERS:
+	case WSAEDQUOT:
+	case WSAESTALE:
+	case WSAEREMOTE:
+	case WSASYSNOTREADY:
+	case WSAVERNOTSUPPORTED:
+	case WSANOTINITIALISED:
+	case WSAEDISCON:
+	case WSAENOMORE:
+	case WSAECANCELLED:
+	case WSAEINVALIDPROCTABLE:
+	case WSAEINVALIDPROVIDER:
+	case WSAEPROVIDERFAILEDINIT:
+	case WSASYSCALLFAILURE:
+	case WSASERVICE_NOT_FOUND:
+	case WSATYPE_NOT_FOUND:
+	case WSA_E_NO_MORE:
+	case WSA_E_CANCELLED:
+	case WSAEREFUSED:
+	case WSAHOST_NOT_FOUND:
+	case WSATRY_AGAIN:
+	case WSANO_RECOVERY:
+	case WSANO_DATA:
+	case WSA_QOS_RECEIVERS:
+	case WSA_QOS_SENDERS:
+	case WSA_QOS_NO_SENDERS:
+	case WSA_QOS_NO_RECEIVERS:
+	case WSA_QOS_REQUEST_CONFIRMED:
+	case WSA_QOS_ADMISSION_FAILURE:
+	case WSA_QOS_POLICY_FAILURE:
+	case WSA_QOS_BAD_STYLE:
+	case WSA_QOS_BAD_OBJECT:
+	case WSA_QOS_TRAFFIC_CTRL_ERROR:
+	case WSA_QOS_GENERIC_ERROR:
+	case WSA_QOS_ESERVICETYPE:
+	case WSA_QOS_EFLOWSPEC:
+	case WSA_QOS_EPROVSPECBUF:
+	case WSA_QOS_EFILTERSTYLE:
+	case WSA_QOS_EFILTERTYPE:
+	case WSA_QOS_EFILTERCOUNT:
+	case WSA_QOS_EOBJLENGTH:
+	case WSA_QOS_EFLOWCOUNT:
+#ifndef _MSC_VER
+	case WSA_QOS_EUNKNOWNPSOBJ:
+#endif
+	case WSA_QOS_EPOLICYOBJ:
+	case WSA_QOS_EFLOWDESC:
+	case WSA_QOS_EPSFLOWSPEC:
+	case WSA_QOS_EPSFILTERSPEC:
+	case WSA_QOS_ESDMODEOBJ:
+	case WSA_QOS_ESHAPERATEOBJ:
+	case WSA_QOS_RESERVED_PETYPE:
+	default: return EIO;
+	}
+}
+
+/*
+ * On Windows, `errno` is a global macro to a function call.
+ * This makes it difficult to debug and single-step our mappings.
+ */
+static inline void set_wsa_errno(void)
+{
+	DWORD wsa = WSAGetLastError();
+	int e = winsock_error_to_errno(wsa);
+	errno = e;
+
+#ifdef DEBUG_WSA_ERRNO
+	fprintf(stderr, "winsock error: %d -> %d\n", wsa, e);
+	fflush(stderr);
+#endif
+}
+
+static inline int winsock_return(int ret)
+{
+	if (ret < 0)
+		set_wsa_errno();
+
+	return ret;
+}
+
+#define WINSOCK_RETURN(x) do { return winsock_return(x); } while (0)
+
 #undef gethostname
 int mingw_gethostname(char *name, int namelen)
 {
-    ensure_socket_initialization();
-    return gethostname(name, namelen);
+	ensure_socket_initialization();
+	WINSOCK_RETURN(gethostname(name, namelen));
 }
 
 #undef gethostbyname
 struct hostent *mingw_gethostbyname(const char *host)
 {
+	struct hostent *ret;
+
 	ensure_socket_initialization();
-	return gethostbyname(host);
+
+	ret = gethostbyname(host);
+	if (!ret)
+		set_wsa_errno();
+
+	return ret;
 }
 
 #undef getaddrinfo
@@ -2060,7 +2192,7 @@ int mingw_getaddrinfo(const char *node, const char *service,
 		      const struct addrinfo *hints, struct addrinfo **res)
 {
 	ensure_socket_initialization();
-	return getaddrinfo(node, service, hints, res);
+	WINSOCK_RETURN(getaddrinfo(node, service, hints, res));
 }
 
 int mingw_socket(int domain, int type, int protocol)
@@ -2080,7 +2212,7 @@ int mingw_socket(int domain, int type, int protocol)
 		 * in errno so that _if_ someone looks up the code somewhere,
 		 * then it is at least the number that are usually listed.
 		 */
-		errno = WSAGetLastError();
+		set_wsa_errno();
 		return -1;
 	}
 	/* convert into a file descriptor */
@@ -2096,35 +2228,35 @@ int mingw_socket(int domain, int type, int protocol)
 int mingw_connect(int sockfd, struct sockaddr *sa, size_t sz)
 {
 	SOCKET s = (SOCKET)_get_osfhandle(sockfd);
-	return connect(s, sa, sz);
+	WINSOCK_RETURN(connect(s, sa, sz));
 }
 
 #undef bind
 int mingw_bind(int sockfd, struct sockaddr *sa, size_t sz)
 {
 	SOCKET s = (SOCKET)_get_osfhandle(sockfd);
-	return bind(s, sa, sz);
+	WINSOCK_RETURN(bind(s, sa, sz));
 }
 
 #undef setsockopt
 int mingw_setsockopt(int sockfd, int lvl, int optname, void *optval, int optlen)
 {
 	SOCKET s = (SOCKET)_get_osfhandle(sockfd);
-	return setsockopt(s, lvl, optname, (const char*)optval, optlen);
+	WINSOCK_RETURN(setsockopt(s, lvl, optname, (const char*)optval, optlen));
 }
 
 #undef shutdown
 int mingw_shutdown(int sockfd, int how)
 {
 	SOCKET s = (SOCKET)_get_osfhandle(sockfd);
-	return shutdown(s, how);
+	WINSOCK_RETURN(shutdown(s, how));
 }
 
 #undef listen
 int mingw_listen(int sockfd, int backlog)
 {
 	SOCKET s = (SOCKET)_get_osfhandle(sockfd);
-	return listen(s, backlog);
+	WINSOCK_RETURN(listen(s, backlog));
 }
 
 #undef accept
@@ -2135,6 +2267,11 @@ int mingw_accept(int sockfd1, struct sockaddr *sa, socklen_t *sz)
 	SOCKET s1 = (SOCKET)_get_osfhandle(sockfd1);
 	SOCKET s2 = accept(s1, sa, sz);
 
+	if (s2 == INVALID_SOCKET) {
+		set_wsa_errno();
+		return -1;
+	}
+
 	/* convert into a file descriptor */
 	if ((sockfd2 = _open_osfhandle(s2, O_RDWR|O_BINARY)) < 0) {
 		int err = errno;

From afee39f6e3ca1d011b7cce7f3208cdbdae9d3299 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 1 Jan 2020 21:07:22 +0100
Subject: [PATCH 038/259] mingw: do resolve symlinks in `getcwd()`

As pointed out in https://github.com/git-for-windows/git/issues/1676,
the `git rev-parse --is-inside-work-tree` command currently fails when
the current directory's path contains symbolic links.

The underlying reason for this bug is that `getcwd()` is supposed to
resolve symbolic links, but our `mingw_getcwd()` implementation did not.

We do have all the building blocks for that, though: the
`GetFinalPathByHandleW()` function will resolve symbolic links. However,
we only called that function if `GetLongPathNameW()` failed, for
historical reasons: the latter function was supported for a long time,
but the former API function was introduced only with Windows Vista, and
we used to support also Windows XP. With that support having been
dropped, we are free to call the symbolic link-resolving function right
away.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 29d3f09768c29a..0c8e526e3ece64 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1141,18 +1141,16 @@ char *mingw_getcwd(char *pointer, int len)
 {
 	wchar_t cwd[MAX_PATH], wpointer[MAX_PATH];
 	DWORD ret = GetCurrentDirectoryW(ARRAY_SIZE(cwd), cwd);
+	HANDLE hnd;
 
 	if (!ret || ret >= ARRAY_SIZE(cwd)) {
 		errno = ret ? ENAMETOOLONG : err_win_to_posix(GetLastError());
 		return NULL;
 	}
-	ret = GetLongPathNameW(cwd, wpointer, ARRAY_SIZE(wpointer));
-	if (!ret && GetLastError() == ERROR_ACCESS_DENIED) {
-		HANDLE hnd = CreateFileW(cwd, 0,
-			FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
-			OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
-		if (hnd == INVALID_HANDLE_VALUE)
-			return NULL;
+	hnd = CreateFileW(cwd, 0,
+			  FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
+			  OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+	if (hnd != INVALID_HANDLE_VALUE) {
 		ret = GetFinalPathNameByHandleW(hnd, wpointer, ARRAY_SIZE(wpointer), 0);
 		CloseHandle(hnd);
 		if (!ret || ret >= ARRAY_SIZE(wpointer))
@@ -1161,13 +1159,11 @@ char *mingw_getcwd(char *pointer, int len)
 			return NULL;
 		return pointer;
 	}
-	if (!ret || ret >= ARRAY_SIZE(wpointer))
-		return NULL;
-	if (GetFileAttributesW(wpointer) == INVALID_FILE_ATTRIBUTES) {
+	if (GetFileAttributesW(cwd) == INVALID_FILE_ATTRIBUTES) {
 		errno = ENOENT;
 		return NULL;
 	}
-	if (xwcstoutf(pointer, wpointer, len) < 0)
+	if (xwcstoutf(pointer, cwd, len) < 0)
 		return NULL;
 	convert_slashes(pointer);
 	return pointer;

From 32bad31b90848a66b1a235ba85d8c0917b4ca1a2 Mon Sep 17 00:00:00 2001
From: Bjoern Mueller <bjoernm@gmx.de>
Date: Wed, 22 Jan 2020 13:49:13 +0100
Subject: [PATCH 039/259] mingw: fix fatal error working on mapped network
 drives on Windows

In 1e64d18 (mingw: do resolve symlinks in `getcwd()`) a problem was
introduced that causes git for Windows to stop working with certain
mapped network drives (in particular, drives that are mapped to
locations with long path names). Error message was "fatal: Unable to
read current working directory: No such file or directory". Present
change fixes this issue as discussed in
https://github.com/git-for-windows/git/issues/2480

Signed-off-by: Bjoern Mueller <bjoernm@gmx.de>
---
 compat/mingw.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 29d3f09768c29a..d45ba0a06400a2 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1155,8 +1155,13 @@ char *mingw_getcwd(char *pointer, int len)
 			return NULL;
 		ret = GetFinalPathNameByHandleW(hnd, wpointer, ARRAY_SIZE(wpointer), 0);
 		CloseHandle(hnd);
-		if (!ret || ret >= ARRAY_SIZE(wpointer))
-			return NULL;
+		if (!ret || ret >= ARRAY_SIZE(wpointer)) {
+			ret = GetLongPathNameW(cwd, wpointer, ARRAY_SIZE(wpointer));
+			if (!ret || ret >= ARRAY_SIZE(wpointer)) {
+				errno = ret ? ENAMETOOLONG : err_win_to_posix(GetLastError());
+				return NULL;
+			}
+		}
 		if (xwcstoutf(pointer, normalize_ntpath(wpointer), len) < 0)
 			return NULL;
 		return pointer;

From e6ec5097af67db72a0ebee09b0e9fa8f36bb3876 Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Thu, 30 Jan 2020 14:22:27 -0500
Subject: [PATCH 040/259] clink.pl: fix MSVC compile script to handle
 libcurl-d.lib

Update clink.pl to link with either libcurl.lib or libcurl-d.lib
depending on whether DEBUG=1 is set.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/vcbuild/scripts/clink.pl | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/compat/vcbuild/scripts/clink.pl b/compat/vcbuild/scripts/clink.pl
index 3bd824154be381..c4c99d1a11f18c 100755
--- a/compat/vcbuild/scripts/clink.pl
+++ b/compat/vcbuild/scripts/clink.pl
@@ -56,7 +56,8 @@
 		# need to use that instead?
 		foreach my $flag (@lflags) {
 			if ($flag =~ /^-LIBPATH:(.*)/) {
-				foreach my $l ("libcurl_imp.lib", "libcurl.lib") {
+				my $libcurl = $is_debug ? "libcurl-d.lib" : "libcurl.lib";
+				foreach my $l ("libcurl_imp.lib", $libcurl) {
 					if (-f "$1/$l") {
 						$lib = $l;
 						last;

From 14c3501a4b550a58d261eff8af3f608f4195b2a9 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 31 Jan 2020 12:02:47 +0100
Subject: [PATCH 041/259] mingw: demonstrate a `git add` issue with NTFS
 junctions

NTFS junctions are somewhat similar in spirit to Unix bind mounts: they
point to a different directory and are resolved by the filesystem
driver. As such, they appear to `lstat()` as if they are directories,
not as if they are symbolic links.

_Any_ user can create junctions, while symbolic links can only be
created by non-administrators in Developer Mode on Windows 10. Hence
NTFS junctions are much more common "in the wild" than NTFS symbolic
links.

It was reported in https://github.com/git-for-windows/git/issues/2481
that adding files via an absolute path that traverses an NTFS junction:
since 1e64d18 (mingw: do resolve symlinks in `getcwd()`), we resolve not
only symbolic links but also NTFS junctions when determining the
absolute path of the current directory. The same is not true for `git
add <file>`, where symbolic links are resolved in `<file>`, but not NTFS
junctions.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t3700-add.sh | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/t/t3700-add.sh b/t/t3700-add.sh
index 839c904745a286..2e0cd98d0e7167 100755
--- a/t/t3700-add.sh
+++ b/t/t3700-add.sh
@@ -549,4 +549,15 @@ test_expect_success CASE_INSENSITIVE_FS 'path is case-insensitive' '
 	git add "$downcased"
 '
 
+test_expect_failure MINGW 'can add files via NTFS junctions' '
+	test_when_finished "cmd //c rmdir junction && rm -rf target" &&
+	test_create_repo target &&
+	cmd //c "mklink /j junction target" &&
+	>target/via-junction &&
+	git -C junction add "$(pwd)/junction/via-junction" &&
+	echo via-junction >expect &&
+	git -C target diff --cached --name-only >actual &&
+	test_cmp expect actual
+'
+
 test_done

From c561389eb64733859a131313917cb84ecda13325 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 21 Feb 2017 13:28:58 +0100
Subject: [PATCH 042/259] mingw: ensure valid CTYPE

A change between versions 2.4.1 and 2.6.0 of the MSYS2 runtime modified
how Cygwin's runtime (and hence Git for Windows' MSYS2 runtime
derivative) handles locales: d16a56306d (Consolidate wctomb/mbtowc calls
for POSIX-1.2008, 2016-07-20).

An unintended side-effect is that "cold-calling" into the POSIX
emulation will start with a locale based on the current code page,
something that Git for Windows is very ill-prepared for, as it expects
to be able to pass a command-line containing non-ASCII characters to the
shell without having those characters munged.

One symptom of this behavior: when `git clone` or `git fetch` shell out
to call `git-upload-pack` with a path that contains non-ASCII
characters, the shell tried to interpret the entire command-line
(including command-line parameters) as executable path, which obviously
must fail.

This fixes https://github.com/git-for-windows/git/issues/1036

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/compat/mingw.c b/compat/mingw.c
index 29d3f09768c29a..f20d36a04113eb 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2669,6 +2669,9 @@ static void setup_windows_environment(void)
 		if (!tmp && (tmp = getenv("USERPROFILE")))
 			setenv("HOME", tmp, 1);
 	}
+
+	if (!getenv("LC_ALL") && !getenv("LC_CTYPE") && !getenv("LANG"))
+		setenv("LC_CTYPE", "C.UTF-8", 1);
 }
 
 static PSID get_current_user_sid(void)

From 8801afca7d321f58244a3b76edd9131906ca2814 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sat, 9 May 2020 14:08:36 +0200
Subject: [PATCH 043/259] vcxproj: unclash project directories with build
 outputs

It already caused problems with the test suite that the directory
containing `git.vcxproj` is called the same as the Git executable
without its file extension: `./git` is ambiguous, it could refer both to
the directory `git/` as well as to `git.exe`.

Now there is one more problem: when our GitHub workflow runs on the
`vs/master` branch, it fails in all but the Windows builds, as they want
to write the file `git` but there is already a directory in the way.

Let's just go ahead and append `.proj` to all of those directories, e.g.
`git.proj/` instead of `git/`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 config.mak.uname                           |  8 ++++----
 contrib/buildsystems/Generators/Vcxproj.pm | 18 ++++++++++--------
 2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/config.mak.uname b/config.mak.uname
index bbf7744ddd5d0f..20ed2c261650b0 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -768,7 +768,7 @@ vcxproj:
 
 	# Make .vcxproj files and add them
 	perl contrib/buildsystems/generate -g Vcxproj
-	git add -f git.sln {*,*/lib,t/helper/*}/*.vcxproj
+	git add -f git.sln {*,*/lib.proj,t/helper/*}/*.vcxproj
 
 	# Generate the LinkOrCopyBuiltins.targets and LinkOrCopyRemoteHttp.targets file
 	(echo '<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">' && \
@@ -778,7 +778,7 @@ vcxproj:
 	   echo '    <Copy SourceFiles="$$(OutDir)\git.exe" DestinationFiles="$$(OutDir)\'"$$name"'" SkipUnchangedFiles="true" UseHardlinksIfPossible="true" />'; \
 	 done && \
 	 echo '  </Target>' && \
-	 echo '</Project>') >git/LinkOrCopyBuiltins.targets
+	 echo '</Project>') >git.proj/LinkOrCopyBuiltins.targets
 	(echo '<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">' && \
 	 echo '  <Target Name="CopyBuiltins_AfterBuild" AfterTargets="AfterBuild">' && \
 	 for name in $(REMOTE_CURL_ALIASES); \
@@ -786,8 +786,8 @@ vcxproj:
 	   echo '    <Copy SourceFiles="$$(OutDir)\'"$(REMOTE_CURL_PRIMARY)"'" DestinationFiles="$$(OutDir)\'"$$name"'" SkipUnchangedFiles="true" UseHardlinksIfPossible="true" />'; \
 	 done && \
 	 echo '  </Target>' && \
-	 echo '</Project>') >git-remote-http/LinkOrCopyRemoteHttp.targets
-	git add -f git/LinkOrCopyBuiltins.targets git-remote-http/LinkOrCopyRemoteHttp.targets
+	 echo '</Project>') >git-remote-http.proj/LinkOrCopyRemoteHttp.targets
+	git add -f git.proj/LinkOrCopyBuiltins.targets git-remote-http.proj/LinkOrCopyRemoteHttp.targets
 
 	# Add generated headers
 	$(MAKE) MSVC=1 SKIP_VCPKG=1 prefix=/mingw64 $(GENERATED_H)
diff --git a/contrib/buildsystems/Generators/Vcxproj.pm b/contrib/buildsystems/Generators/Vcxproj.pm
index b2e68a16715e39..0439b82f55e243 100644
--- a/contrib/buildsystems/Generators/Vcxproj.pm
+++ b/contrib/buildsystems/Generators/Vcxproj.pm
@@ -58,8 +58,8 @@ sub createProject {
     my $uuid = generate_guid($name);
     $$build_structure{"$prefix${target}_GUID"} = $uuid;
     my $vcxproj = $target;
-    $vcxproj =~ s/(.*\/)?(.*)/$&\/$2.vcxproj/;
-    $vcxproj =~ s/([^\/]*)(\/lib)\/(lib.vcxproj)/$1$2\/$1_$3/;
+    $vcxproj =~ s/(.*\/)?(.*)/$&.proj\/$2.vcxproj/;
+    $vcxproj =~ s/([^\/]*)(\/lib\.proj)\/(lib.vcxproj)/$1$2\/$1_$3/;
     $$build_structure{"$prefix${target}_VCXPROJ"} = $vcxproj;
 
     my @srcs = sort(map("$rel_dir\\$_", @{$$build_structure{"$prefix${name}_SOURCES"}}));
@@ -89,7 +89,9 @@ sub createProject {
     $defines =~ s/>/&gt;/g;
     $defines =~ s/\'//g;
 
-    die "Could not create the directory $target for $label project!\n" unless (-d "$target" || mkdir "$target");
+    my $dir = $vcxproj;
+    $dir =~ s/\/[^\/]*$//;
+    die "Could not create the directory $dir for $label project!\n" unless (-d "$dir" || mkdir "$dir");
 
     open F, ">$vcxproj" or die "Could not open $vcxproj for writing!\n";
     binmode F, ":crlf :utf8";
@@ -237,7 +239,7 @@ EOM
 
       print F << "EOM";
   <ItemGroup>
-    <ProjectReference Include="$cdup\\libgit\\libgit.vcxproj">
+    <ProjectReference Include="$cdup\\libgit.proj\\libgit.vcxproj">
       <Project>$uuid_libgit</Project>
       <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
     </ProjectReference>
@@ -252,7 +254,7 @@ EOM
       }
       if (!($name =~ 'xdiff')) {
         print F << "EOM";
-    <ProjectReference Include="$cdup\\xdiff\\lib\\xdiff_lib.vcxproj">
+    <ProjectReference Include="$cdup\\xdiff\\lib.proj\\xdiff_lib.vcxproj">
       <Project>$uuid_xdiff_lib</Project>
       <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
     </ProjectReference>
@@ -261,7 +263,7 @@ EOM
       if ($name =~ /(test-(line-buffer|svn-fe)|^git-remote-testsvn)\.exe$/) {
         my $uuid_vcs_svn_lib = $$build_structure{"LIBS_vcs-svn/lib_GUID"};
         print F << "EOM";
-    <ProjectReference Include="$cdup\\vcs-svn\\lib\\vcs-svn_lib.vcxproj">
+    <ProjectReference Include="$cdup\\vcs-svn\\lib.proj\\vcs-svn_lib.vcxproj">
       <Project>$uuid_vcs_svn_lib</Project>
       <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
     </ProjectReference>
@@ -338,7 +340,7 @@ sub createGlueProject {
 	my $vcxproj = $build_structure{"APPS_${appname}_VCXPROJ"};
 	$vcxproj =~ s/\//\\/g;
         $appname =~ s/.*\///;
-        print F "\"${appname}\", \"${vcxproj}\", \"${uuid}\"";
+        print F "\"${appname}.proj\", \"${vcxproj}\", \"${uuid}\"";
         print F "$SLN_POST";
     }
     foreach (@libs) {
@@ -348,7 +350,7 @@ sub createGlueProject {
         my $vcxproj = $build_structure{"LIBS_${libname}_VCXPROJ"};
 	$vcxproj =~ s/\//\\/g;
         $libname =~ s/\//_/g;
-        print F "\"${libname}\", \"${vcxproj}\", \"${uuid}\"";
+        print F "\"${libname}.proj\", \"${vcxproj}\", \"${uuid}\"";
         print F "$SLN_POST";
     }
 

From 367af8a40bb9244c82220db89e4b33cf3d8647ec Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 31 Jan 2020 11:44:31 +0100
Subject: [PATCH 044/259] strbuf_realpath(): use platform-dependent API if
 available

Some platforms (e.g. Windows) provide API functions to resolve paths
much quicker. Let's offer a way to short-cut `strbuf_realpath()` on
those platforms.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 abspath.c         | 3 +++
 git-compat-util.h | 4 ++++
 2 files changed, 7 insertions(+)

diff --git a/abspath.c b/abspath.c
index 1202cde23dbc9b..0c17e98654e4b0 100644
--- a/abspath.c
+++ b/abspath.c
@@ -93,6 +93,9 @@ static char *strbuf_realpath_1(struct strbuf *resolved, const char *path,
 			goto error_out;
 	}
 
+	if (platform_strbuf_realpath(resolved, path))
+		return resolved->buf;
+
 	strbuf_addstr(&remaining, path);
 	get_root_part(resolved, &remaining);
 
diff --git a/git-compat-util.h b/git-compat-util.h
index 71b4d23f0386b2..6c5d2e18d203dc 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -607,6 +607,10 @@ static inline int git_has_dir_sep(const char *path)
 #define query_user_email() NULL
 #endif
 
+#ifndef platform_strbuf_realpath
+#define platform_strbuf_realpath(resolved, path) NULL
+#endif
+
 #ifdef __TANDEM
 #include <floss.h(floss_execl,floss_execlp,floss_execv,floss_execvp)>
 #include <floss.h(floss_getpwuid)>

From b31479666d21bcd7e8928b105c2334f61017234f Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sat, 1 Feb 2020 00:31:16 +0100
Subject: [PATCH 045/259] mingw: allow `git.exe` to be used instead of the "Git
 wrapper"

Git for Windows wants to add `git.exe` to the users' `PATH`, without
cluttering the latter with unnecessary executables such as `wish.exe`.
To that end, it invented the concept of its "Git wrapper", i.e. a tiny
executable located in `C:\Program Files\Git\cmd\git.exe` (originally a
CMD script) whose sole purpose is to set up a couple of environment
variables and then spawn the _actual_ `git.exe` (which nowadays lives in
`C:\Program Files\Git\mingw64\bin\git.exe` for 64-bit, and the obvious
equivalent for 32-bit installations).

Currently, the following environment variables are set unless already
initialized:

- `MSYSTEM`, to make sure that the MSYS2 Bash and the MSYS2 Perl
  interpreter behave as expected, and

- `PLINK_PROTOCOL`, to force PuTTY's `plink.exe` to use the SSH
  protocol instead of Telnet,

- `PATH`, to make sure that the `bin` folder in the user's home
  directory, as well as the `/mingw64/bin` and the `/usr/bin`
  directories are included. The trick here is that the `/mingw64/bin/`
  and `/usr/bin/` directories are relative to the top-level installation
  directory of Git for Windows (which the included Bash interprets as
  `/`, i.e. as the MSYS pseudo root directory).

Using the absence of `MSYSTEM` as a tell-tale, we can detect in
`git.exe` whether these environment variables have been initialized
properly. Therefore we can call `C:\Program Files\Git\mingw64\bin\git`
in-place after this change, without having to call Git through the Git
wrapper.

Obviously, above-mentioned directories must be _prepended_ to the `PATH`
variable, otherwise we risk picking up executables from unrelated Git
installations. We do that by constructing the new `PATH` value from
scratch, appending `$HOME/bin` (if `HOME` is set), then the MSYS2 system
directories, and then appending the original `PATH`.

Side note: this modification of the `PATH` variable is independent of
the modification necessary to reach the executables and scripts in
`/mingw64/libexec/git-core/`, i.e. the `GIT_EXEC_PATH`. That
modification is still performed by Git, elsewhere, long after making the
changes described above.

While we _still_ cannot simply hard-link `mingw64\bin\git.exe` to `cmd`
(because the former depends on a couple of `.dll` files that are only in
`mingw64\bin`, i.e. calling `...\cmd\git.exe` would fail to load due to
missing dependencies), at least we can now avoid that extra process of
running the Git wrapper (which then has to wait for the spawned
`git.exe` to finish) by calling `...\mingw64\bin\git.exe` directly, via
its absolute path.

Testing this is in Git's test suite tricky: we set up a "new" MSYS
pseudo-root and copy the `git.exe` file into the appropriate location,
then verify that `MSYSTEM` is set properly, and also that the `PATH` is
modified so that scripts can be found in `$HOME/bin`, `/mingw64/bin/`
and `/usr/bin/`.

This addresses https://github.com/git-for-windows/git/issues/2283

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c        | 69 +++++++++++++++++++++++++++++++++++++++++++
 config.mak.uname      |  4 +--
 t/t0060-path-utils.sh | 31 ++++++++++++++++++-
 3 files changed, 101 insertions(+), 3 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index f20d36a04113eb..3ec814aa1e8f2a 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2618,6 +2618,47 @@ int xwcstoutf(char *utf, const wchar_t *wcs, size_t utflen)
 	return -1;
 }
 
+#ifdef ENSURE_MSYSTEM_IS_SET
+static size_t append_system_bin_dirs(char *path, size_t size)
+{
+#if !defined(RUNTIME_PREFIX) || !defined(HAVE_WPGMPTR)
+	return 0;
+#else
+	char prefix[32768];
+	const char *slash;
+	size_t len = xwcstoutf(prefix, _wpgmptr, sizeof(prefix)), off = 0;
+
+	if (len == 0 || len >= sizeof(prefix) ||
+	    !(slash = find_last_dir_sep(prefix)))
+		return 0;
+	/* strip trailing `git.exe` */
+	len = slash - prefix;
+
+	/* strip trailing `cmd` or `mingw64\bin` or `mingw32\bin` or `bin` or `libexec\git-core` */
+	if (strip_suffix_mem(prefix, &len, "\\mingw64\\libexec\\git-core") ||
+	    strip_suffix_mem(prefix, &len, "\\mingw64\\bin"))
+		off += xsnprintf(path + off, size - off,
+				 "%.*s\\mingw64\\bin;", (int)len, prefix);
+	else if (strip_suffix_mem(prefix, &len, "\\mingw32\\libexec\\git-core") ||
+		 strip_suffix_mem(prefix, &len, "\\mingw32\\bin"))
+		off += xsnprintf(path + off, size - off,
+				 "%.*s\\mingw32\\bin;", (int)len, prefix);
+	else if (strip_suffix_mem(prefix, &len, "\\cmd") ||
+		 strip_suffix_mem(prefix, &len, "\\bin") ||
+		 strip_suffix_mem(prefix, &len, "\\libexec\\git-core"))
+		off += xsnprintf(path + off, size - off,
+				 "%.*s\\mingw%d\\bin;", (int)len, prefix,
+				 (int)(sizeof(void *) * 8));
+	else
+		return 0;
+
+	off += xsnprintf(path + off, size - off,
+			 "%.*s\\usr\\bin;", (int)len, prefix);
+	return off;
+#endif
+}
+#endif
+
 static void setup_windows_environment(void)
 {
 	char *tmp = getenv("TMPDIR");
@@ -2670,6 +2711,34 @@ static void setup_windows_environment(void)
 			setenv("HOME", tmp, 1);
 	}
 
+	if (!getenv("PLINK_PROTOCOL"))
+		setenv("PLINK_PROTOCOL", "ssh", 0);
+
+#ifdef ENSURE_MSYSTEM_IS_SET
+	if (!(tmp = getenv("MSYSTEM")) || !tmp[0]) {
+		const char *home = getenv("HOME"), *path = getenv("PATH");
+		char buf[32768];
+		size_t off = 0;
+
+		xsnprintf(buf, sizeof(buf),
+			  "MINGW%d", (int)(sizeof(void *) * 8));
+		setenv("MSYSTEM", buf, 1);
+
+		if (home)
+			off += xsnprintf(buf + off, sizeof(buf) - off,
+					 "%s\\bin;", home);
+		off += append_system_bin_dirs(buf + off, sizeof(buf) - off);
+		if (path)
+			off += xsnprintf(buf + off, sizeof(buf) - off,
+					 "%s", path);
+		else if (off > 0)
+			buf[off - 1] = '\0';
+		else
+			buf[0] = '\0';
+		setenv("PATH", buf, 1);
+	}
+#endif
+
 	if (!getenv("LC_ALL") && !getenv("LC_CTYPE") && !getenv("LANG"))
 		setenv("LC_CTYPE", "C.UTF-8", 1);
 }
diff --git a/config.mak.uname b/config.mak.uname
index bbf7744ddd5d0f..a429e09800a947 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -502,7 +502,7 @@ endif
 		compat/win32/pthread.o compat/win32/syslog.o \
 		compat/win32/trace2_win32_process_info.o \
 		compat/win32/dirent.o
-	COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DDETECT_MSYS_TTY -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
+	COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DDETECT_MSYS_TTY -DENSURE_MSYSTEM_IS_SET -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
 	BASIC_LDFLAGS = -IGNORE:4217 -IGNORE:4049 -NOLOGO -ENTRY:wmainCRTStartup -SUBSYSTEM:CONSOLE
 	# invalidcontinue.obj allows Git's source code to close the same file
 	# handle twice, or to access the osfhandle of an already-closed stdout
@@ -730,7 +730,7 @@ ifeq ($(uname_S),MINGW)
         endif
 	CC = gcc
 	COMPAT_CFLAGS += -D__USE_MINGW_ANSI_STDIO=0 -DDETECT_MSYS_TTY \
-		-fstack-protector-strong
+		-DENSURE_MSYSTEM_IS_SET -fstack-protector-strong
 	EXTLIBS += -lntdll
 	EXTRA_PROGRAMS += headless-git$X
 	INSTALL = /bin/install
diff --git a/t/t0060-path-utils.sh b/t/t0060-path-utils.sh
index 0afa3d0d312ca6..e73835e41b96e4 100755
--- a/t/t0060-path-utils.sh
+++ b/t/t0060-path-utils.sh
@@ -599,7 +599,8 @@ test_expect_success !VALGRIND,RUNTIME_PREFIX,CAN_EXEC_IN_PWD 'RUNTIME_PREFIX wor
 	cp "$GIT_EXEC_PATH"/git$X pretend/bin/ &&
 	GIT_EXEC_PATH= ./pretend/bin/git here >actual &&
 	echo HERE >expect &&
-	test_cmp expect actual'
+	test_cmp expect actual
+'
 
 test_expect_success !VALGRIND,RUNTIME_PREFIX,CAN_EXEC_IN_PWD '%(prefix)/ works' '
 	mkdir -p pretend/bin &&
@@ -610,4 +611,32 @@ test_expect_success !VALGRIND,RUNTIME_PREFIX,CAN_EXEC_IN_PWD '%(prefix)/ works'
 	test_cmp expect actual
 '
 
+test_expect_success MINGW 'MSYSTEM/PATH is adjusted if necessary' '
+	mkdir -p "$HOME"/bin pretend/mingw64/bin \
+		pretend/mingw64/libexec/git-core pretend/usr/bin &&
+	cp "$GIT_EXEC_PATH"/git.exe pretend/mingw64/bin/ &&
+	cp "$GIT_EXEC_PATH"/git.exe pretend/mingw64/libexec/git-core/ &&
+	# copy the .dll files, if any (happens when building via CMake)
+	case "$GIT_EXEC_PATH"/*.dll in
+	*/"*.dll") ;; # no `.dll` files to be copied
+	*)
+		cp "$GIT_EXEC_PATH"/*.dll pretend/mingw64/bin/ &&
+		cp "$GIT_EXEC_PATH"/*.dll pretend/mingw64/libexec/git-core/
+		;;
+	esac &&
+	echo "env | grep MSYSTEM=" | write_script "$HOME"/bin/git-test-home &&
+	echo "echo mingw64" | write_script pretend/mingw64/bin/git-test-bin &&
+	echo "echo usr" | write_script pretend/usr/bin/git-test-bin2 &&
+
+	(
+		MSYSTEM= &&
+		GIT_EXEC_PATH= &&
+		pretend/mingw64/libexec/git-core/git.exe test-home >actual &&
+		pretend/mingw64/libexec/git-core/git.exe test-bin >>actual &&
+		pretend/mingw64/bin/git.exe test-bin2 >>actual
+	) &&
+	test_write_lines MSYSTEM=$MSYSTEM mingw64 usr >expect &&
+	test_cmp expect actual
+'
+
 test_done

From 189d1cd5936303d43c01daf6bc60cfbc299e18b0 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sat, 9 May 2020 16:19:06 +0200
Subject: [PATCH 046/259] t5505/t5516: allow running without `.git/branches/`
 in the templates

When we commit the template directory as part of `make vcxproj`, the
`branches/` directory is not actually commited, as it is empty.

Two tests were not prepared for that situation.

This developer tried to get rid of the support for `.git/branches/` a
long time ago, but that effort did not bear fruit, so the best we can do
is work around in these here tests.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t5505-remote.sh     | 4 ++--
 t/t5516-fetch-push.sh | 8 ++++----
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/t/t5505-remote.sh b/t/t5505-remote.sh
index 08424e878e104c..c3728f2065987e 100755
--- a/t/t5505-remote.sh
+++ b/t/t5505-remote.sh
@@ -1039,7 +1039,7 @@ test_expect_success 'migrate a remote from named file in $GIT_DIR/branches' '
 	(
 		cd six &&
 		git remote rm origin &&
-		mkdir .git/branches &&
+		mkdir -p .git/branches &&
 		echo "$origin_url#main" >.git/branches/origin &&
 		git remote rename origin origin &&
 		test_path_is_missing .git/branches/origin &&
@@ -1054,7 +1054,7 @@ test_expect_success 'migrate a remote from named file in $GIT_DIR/branches (2)'
 	(
 		cd seven &&
 		git remote rm origin &&
-		mkdir .git/branches &&
+		mkdir -p .git/branches &&
 		echo "quux#foom" > .git/branches/origin &&
 		git remote rename origin origin &&
 		test_path_is_missing .git/branches/origin &&
diff --git a/t/t5516-fetch-push.sh b/t/t5516-fetch-push.sh
index 9d693eb57f7790..7827db70b53b06 100755
--- a/t/t5516-fetch-push.sh
+++ b/t/t5516-fetch-push.sh
@@ -979,7 +979,7 @@ test_expect_success 'fetch with branches' '
 	mk_empty testrepo &&
 	git branch second $the_first_commit &&
 	git checkout second &&
-	mkdir testrepo/.git/branches &&
+	mkdir -p testrepo/.git/branches &&
 	echo ".." > testrepo/.git/branches/branch1 &&
 	(
 		cd testrepo &&
@@ -993,7 +993,7 @@ test_expect_success 'fetch with branches' '
 
 test_expect_success 'fetch with branches containing #' '
 	mk_empty testrepo &&
-	mkdir testrepo/.git/branches &&
+	mkdir -p testrepo/.git/branches &&
 	echo "..#second" > testrepo/.git/branches/branch2 &&
 	(
 		cd testrepo &&
@@ -1010,7 +1010,7 @@ test_expect_success 'push with branches' '
 	git checkout second &&
 
 	test_when_finished "rm -rf .git/branches" &&
-	mkdir .git/branches &&
+	mkdir -p .git/branches &&
 	echo "testrepo" > .git/branches/branch1 &&
 
 	git push branch1 &&
@@ -1026,7 +1026,7 @@ test_expect_success 'push with branches containing #' '
 	mk_empty testrepo &&
 
 	test_when_finished "rm -rf .git/branches" &&
-	mkdir .git/branches &&
+	mkdir -p .git/branches &&
 	echo "testrepo#branch3" > .git/branches/branch2 &&
 
 	git push branch2 &&

From 884fbfbf76bfc348f4ec376d9cb563cff4a95b61 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 31 Jan 2020 11:49:04 +0100
Subject: [PATCH 047/259] mingw: implement a platform-specific
 `strbuf_realpath()`

There is a Win32 API function to resolve symbolic links, and we can use
that instead of resolving them manually. Even better, this function also
resolves NTFS junction points (which are somewhat similar to bind
mounts).

This fixes https://github.com/git-for-windows/git/issues/2481.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c        | 76 +++++++++++++++++++++++++++++++++++++++++++
 compat/mingw.h        |  3 ++
 t/t0060-path-utils.sh |  8 +++++
 t/t3700-add.sh        |  2 +-
 t/t5601-clone.sh      |  7 ++++
 5 files changed, 95 insertions(+), 1 deletion(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 29d3f09768c29a..e9d2b4d11c8e8c 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1137,6 +1137,82 @@ struct tm *localtime_r(const time_t *timep, struct tm *result)
 }
 #endif
 
+char *mingw_strbuf_realpath(struct strbuf *resolved, const char *path)
+{
+	wchar_t wpath[MAX_PATH];
+	HANDLE h;
+	DWORD ret;
+	int len;
+	const char *last_component = NULL;
+	char *append = NULL;
+
+	if (xutftowcs_path(wpath, path) < 0)
+		return NULL;
+
+	h = CreateFileW(wpath, 0,
+			FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
+			OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+
+	/*
+	 * strbuf_realpath() allows the last path component to not exist. If
+	 * that is the case, now it's time to try without last component.
+	 */
+	if (h == INVALID_HANDLE_VALUE &&
+	    GetLastError() == ERROR_FILE_NOT_FOUND) {
+		/* cut last component off of `wpath` */
+		wchar_t *p = wpath + wcslen(wpath);
+
+		while (p != wpath)
+			if (*(--p) == L'/' || *p == L'\\')
+				break; /* found start of last component */
+
+		if (p != wpath && (last_component = find_last_dir_sep(path))) {
+			append = xstrdup(last_component + 1); /* skip directory separator */
+			/*
+			 * Do not strip the trailing slash at the drive root, otherwise
+			 * the path would be e.g. `C:` (which resolves to the
+			 * _current_ directory on that drive).
+			 */
+			if (p[-1] == L':')
+				p[1] = L'\0';
+			else
+				*p = L'\0';
+			h = CreateFileW(wpath, 0, FILE_SHARE_READ |
+					FILE_SHARE_WRITE | FILE_SHARE_DELETE,
+					NULL, OPEN_EXISTING,
+					FILE_FLAG_BACKUP_SEMANTICS, NULL);
+		}
+	}
+
+	if (h == INVALID_HANDLE_VALUE) {
+realpath_failed:
+		FREE_AND_NULL(append);
+		return NULL;
+	}
+
+	ret = GetFinalPathNameByHandleW(h, wpath, ARRAY_SIZE(wpath), 0);
+	CloseHandle(h);
+	if (!ret || ret >= ARRAY_SIZE(wpath))
+		goto realpath_failed;
+
+	len = wcslen(wpath) * 3;
+	strbuf_grow(resolved, len);
+	len = xwcstoutf(resolved->buf, normalize_ntpath(wpath), len);
+	if (len < 0)
+		goto realpath_failed;
+	resolved->len = len;
+
+	if (append) {
+		/* Use forward-slash, like `normalize_ntpath()` */
+		strbuf_complete(resolved, '/');
+		strbuf_addstr(resolved, append);
+		FREE_AND_NULL(append);
+	}
+
+	return resolved->buf;
+
+}
+
 char *mingw_getcwd(char *pointer, int len)
 {
 	wchar_t cwd[MAX_PATH], wpointer[MAX_PATH];
diff --git a/compat/mingw.h b/compat/mingw.h
index 27b61284f46be6..150ce2432f8f99 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -457,6 +457,9 @@ static inline void convert_slashes(char *path)
 #define PATH_SEP ';'
 char *mingw_query_user_email(void);
 #define query_user_email mingw_query_user_email
+struct strbuf;
+char *mingw_strbuf_realpath(struct strbuf *resolved, const char *path);
+#define platform_strbuf_realpath mingw_strbuf_realpath
 #if !defined(__MINGW64_VERSION_MAJOR) && (!defined(_MSC_VER) || _MSC_VER < 1800)
 #define PRIuMAX "I64u"
 #define PRId64 "I64d"
diff --git a/t/t0060-path-utils.sh b/t/t0060-path-utils.sh
index 0afa3d0d312ca6..7a31cdd0d0ca48 100755
--- a/t/t0060-path-utils.sh
+++ b/t/t0060-path-utils.sh
@@ -282,6 +282,14 @@ test_expect_success SYMLINKS 'real path works on symlinks' '
 	test_cmp expect actual
 '
 
+test_expect_success MINGW 'real path works near drive root' '
+	# we need a non-existing path at the drive root; simply skip if C:/xyz exists
+	if test ! -e C:/xyz
+	then
+		test C:/xyz = $(test-tool path-utils real_path C:/xyz)
+	fi
+'
+
 test_expect_success SYMLINKS 'prefix_path works with absolute paths to work tree symlinks' '
 	ln -s target symlink &&
 	echo "symlink" >expect &&
diff --git a/t/t3700-add.sh b/t/t3700-add.sh
index 2e0cd98d0e7167..ad7a0e925b195e 100755
--- a/t/t3700-add.sh
+++ b/t/t3700-add.sh
@@ -549,7 +549,7 @@ test_expect_success CASE_INSENSITIVE_FS 'path is case-insensitive' '
 	git add "$downcased"
 '
 
-test_expect_failure MINGW 'can add files via NTFS junctions' '
+test_expect_success MINGW 'can add files via NTFS junctions' '
 	test_when_finished "cmd //c rmdir junction && rm -rf target" &&
 	test_create_repo target &&
 	cmd //c "mklink /j junction target" &&
diff --git a/t/t5601-clone.sh b/t/t5601-clone.sh
index 5d7ea147f1abc5..6ee5495a32ab73 100755
--- a/t/t5601-clone.sh
+++ b/t/t5601-clone.sh
@@ -78,6 +78,13 @@ test_expect_success 'clone respects GIT_WORK_TREE' '
 
 '
 
+test_expect_success CASE_INSENSITIVE_FS 'core.worktree is not added due to path case' '
+
+	mkdir UPPERCASE &&
+	git clone src "$(pwd)/uppercase" &&
+	test "unset" = "$(git -C UPPERCASE config --default unset core.worktree)"
+'
+
 test_expect_success 'clone from hooks' '
 
 	test_create_repo r0 &&

From d83f5e8029f7bfeabfbbb4d108cab22981611256 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 25 Aug 2020 12:13:26 +0200
Subject: [PATCH 048/259] mingw: ignore HOMEDRIVE/HOMEPATH if it points to
 Windows' system directory

Internally, Git expects the environment variable `HOME` to be set, and
to point to the current user's home directory.

This environment variable is not set by default on Windows, and
therefore Git tries its best to construct one if it finds `HOME` unset.

There are actually two different approaches Git tries: first, it looks
at `HOMEDRIVE`/`HOMEPATH` because this is widely used in corporate
environments with roaming profiles, and a user generally wants their
global Git settings to be in a roaming profile.

Only when `HOMEDRIVE`/`HOMEPATH` is either unset or does not point to a
valid location, Git will fall back to using `USERPROFILE` instead.

However, starting with Windows Vista, for secondary logons and services,
the environment variables `HOMEDRIVE`/`HOMEPATH` point to Windows'
system directory (usually `C:\Windows\system32`).

That is undesirable, and that location is usually write-protected anyway.

So let's verify that the `HOMEDRIVE`/`HOMEPATH` combo does not point to
Windows' system directory before using it, falling back to `USERPROFILE`
if it does.

This fixes git-for-windows#2709

Initial-Path-by: Ivan Pozdeev <vano@mail.mipt.ru>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 3ec814aa1e8f2a..7a98ce22273b3a 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2659,6 +2659,18 @@ static size_t append_system_bin_dirs(char *path, size_t size)
 }
 #endif
 
+static int is_system32_path(const char *path)
+{
+	WCHAR system32[MAX_PATH], wpath[MAX_PATH];
+
+	if (xutftowcs_path(wpath, path) < 0 ||
+	    !GetSystemDirectoryW(system32, ARRAY_SIZE(system32)) ||
+	    _wcsicmp(system32, wpath))
+		return 0;
+
+	return 1;
+}
+
 static void setup_windows_environment(void)
 {
 	char *tmp = getenv("TMPDIR");
@@ -2699,7 +2711,8 @@ static void setup_windows_environment(void)
 			strbuf_addstr(&buf, tmp);
 			if ((tmp = getenv("HOMEPATH"))) {
 				strbuf_addstr(&buf, tmp);
-				if (is_directory(buf.buf))
+				if (!is_system32_path(buf.buf) &&
+				    is_directory(buf.buf))
 					setenv("HOME", buf.buf, 1);
 				else
 					tmp = NULL; /* use $USERPROFILE */

From 27e161a46a7759b4f0631f2a70620acab53c480d Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 4 Mar 2020 21:55:28 +0100
Subject: [PATCH 049/259] http: use new "best effort" strategy for Secure
 Channel revoke checking
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The native Windows HTTPS backend is based on Secure Channel which lets
the caller decide how to handle revocation checking problems caused by
missing information in the certificate or offline CRL distribution
points.

Unfortunately, cURL chose to handle these problems differently than
OpenSSL by default: while OpenSSL happily ignores those problems
(essentially saying "¯\_(ツ)_/¯"), the Secure Channel backend will error
out instead.

As a remedy, the "no revoke" mode was introduced, which turns off
revocation checking altogether. This is a bit heavy-handed. We support
this via the `http.schannelCheckRevoke` setting.

In https://github.com/curl/curl/pull/4981, we contributed an opt-in
"best effort" strategy that emulates what OpenSSL seems to do.

In Git for Windows, we actually want this to be the default. This patch
makes it so, introducing it as a new value for the
`http.schannelCheckRevoke" setting, which now becmes a tristate: it
accepts the values "false", "true" or "best-effort" (defaulting to the
last one).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 Documentation/config/http.txt | 12 +++++++-----
 http.c                        | 26 ++++++++++++++++++++++----
 2 files changed, 29 insertions(+), 9 deletions(-)

diff --git a/Documentation/config/http.txt b/Documentation/config/http.txt
index 162b33fc52f967..101487cfa43a32 100644
--- a/Documentation/config/http.txt
+++ b/Documentation/config/http.txt
@@ -218,11 +218,13 @@ http.sslBackend::
 
 http.schannelCheckRevoke::
 	Used to enforce or disable certificate revocation checks in cURL
-	when http.sslBackend is set to "schannel". Defaults to `true` if
-	unset. Only necessary to disable this if Git consistently errors
-	and the message is about checking the revocation status of a
-	certificate. This option is ignored if cURL lacks support for
-	setting the relevant SSL option at runtime.
+	when http.sslBackend is set to "schannel" via "true" and "false",
+	respectively. Another accepted value is "best-effort" (the default)
+	in which case revocation checks are performed, but errors due to
+	revocation list distribution points that are offline are silently
+	ignored, as well as errors due to certificates missing revocation
+	list distribution points. This option is ignored if cURL lacks
+	support for setting the relevant SSL option at runtime.
 
 http.schannelUseSSLCAInfo::
 	As of cURL v7.60.0, the Secure Channel backend can use the
diff --git a/http.c b/http.c
index 623ed234891f44..f9c55c5cacff37 100644
--- a/http.c
+++ b/http.c
@@ -147,7 +147,13 @@ static char *cached_accept_language;
 
 static char *http_ssl_backend;
 
-static int http_schannel_check_revoke = 1;
+static int http_schannel_check_revoke_mode =
+#ifdef CURLSSLOPT_REVOKE_BEST_EFFORT
+	CURLSSLOPT_REVOKE_BEST_EFFORT;
+#else
+	CURLSSLOPT_NO_REVOKE;
+#endif
+
 /*
  * With the backend being set to `schannel`, setting sslCAinfo would override
  * the Certificate Store in cURL v7.60.0 and later, which is not what we want
@@ -422,7 +428,19 @@ static int http_options(const char *var, const char *value,
 	}
 
 	if (!strcmp("http.schannelcheckrevoke", var)) {
-		http_schannel_check_revoke = git_config_bool(var, value);
+		if (value && !strcmp(value, "best-effort")) {
+			http_schannel_check_revoke_mode =
+#ifdef CURLSSLOPT_REVOKE_BEST_EFFORT
+				CURLSSLOPT_REVOKE_BEST_EFFORT;
+#else
+				CURLSSLOPT_NO_REVOKE;
+			warning(_("%s=%s unsupported by current cURL"),
+				var, value);
+#endif
+		} else
+			http_schannel_check_revoke_mode =
+				(git_config_bool(var, value) ?
+				 0 : CURLSSLOPT_NO_REVOKE);
 		return 0;
 	}
 
@@ -1084,9 +1102,9 @@ static CURL *get_curl_handle(void)
 #endif
 
 	if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
-	    !http_schannel_check_revoke) {
+	    http_schannel_check_revoke_mode) {
 #ifdef GIT_CURL_HAVE_CURLSSLOPT_NO_REVOKE
-		curl_easy_setopt(result, CURLOPT_SSL_OPTIONS, CURLSSLOPT_NO_REVOKE);
+		curl_easy_setopt(result, CURLOPT_SSL_OPTIONS, http_schannel_check_revoke_mode);
 #else
 		warning(_("CURLSSLOPT_NO_REVOKE not supported with cURL < 7.44.0"));
 #endif

From fc86e022ae6a07cf0850eed1e10e3254bf71d009 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sat, 9 May 2020 19:24:23 +0200
Subject: [PATCH 050/259] t5505/t5516: fix white-space around redirectors

The convention in Git project's shell scripts is to have white-space
_before_, but not _after_ the `>` (or `<`).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t5505-remote.sh     |  6 +++---
 t/t5516-fetch-push.sh | 10 +++++-----
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/t/t5505-remote.sh b/t/t5505-remote.sh
index c3728f2065987e..57fdd3f9ab5a48 100755
--- a/t/t5505-remote.sh
+++ b/t/t5505-remote.sh
@@ -835,8 +835,8 @@ test_expect_success '"remote show" does not show symbolic refs' '
 	(
 		cd three &&
 		git remote show origin >output &&
-		! grep "^ *HEAD$" < output &&
-		! grep -i stale < output
+		! grep "^ *HEAD$" <output &&
+		! grep -i stale <output
 	)
 '
 
@@ -1055,7 +1055,7 @@ test_expect_success 'migrate a remote from named file in $GIT_DIR/branches (2)'
 		cd seven &&
 		git remote rm origin &&
 		mkdir -p .git/branches &&
-		echo "quux#foom" > .git/branches/origin &&
+		echo "quux#foom" >.git/branches/origin &&
 		git remote rename origin origin &&
 		test_path_is_missing .git/branches/origin &&
 		test "$(git config remote.origin.url)" = "quux" &&
diff --git a/t/t5516-fetch-push.sh b/t/t5516-fetch-push.sh
index 7827db70b53b06..1fc37f2350aa3d 100755
--- a/t/t5516-fetch-push.sh
+++ b/t/t5516-fetch-push.sh
@@ -980,7 +980,7 @@ test_expect_success 'fetch with branches' '
 	git branch second $the_first_commit &&
 	git checkout second &&
 	mkdir -p testrepo/.git/branches &&
-	echo ".." > testrepo/.git/branches/branch1 &&
+	echo ".." >testrepo/.git/branches/branch1 &&
 	(
 		cd testrepo &&
 		git fetch branch1 &&
@@ -994,7 +994,7 @@ test_expect_success 'fetch with branches' '
 test_expect_success 'fetch with branches containing #' '
 	mk_empty testrepo &&
 	mkdir -p testrepo/.git/branches &&
-	echo "..#second" > testrepo/.git/branches/branch2 &&
+	echo "..#second" >testrepo/.git/branches/branch2 &&
 	(
 		cd testrepo &&
 		git fetch branch2 &&
@@ -1011,7 +1011,7 @@ test_expect_success 'push with branches' '
 
 	test_when_finished "rm -rf .git/branches" &&
 	mkdir -p .git/branches &&
-	echo "testrepo" > .git/branches/branch1 &&
+	echo "testrepo" >.git/branches/branch1 &&
 
 	git push branch1 &&
 	(
@@ -1027,7 +1027,7 @@ test_expect_success 'push with branches containing #' '
 
 	test_when_finished "rm -rf .git/branches" &&
 	mkdir -p .git/branches &&
-	echo "testrepo#branch3" > .git/branches/branch2 &&
+	echo "testrepo#branch3" >.git/branches/branch2 &&
 
 	git push branch2 &&
 	(
@@ -1556,7 +1556,7 @@ EOF
 	git init no-thin &&
 	git --git-dir=no-thin/.git config receive.unpacklimit 0 &&
 	git push no-thin/.git refs/heads/main:refs/heads/foo &&
-	echo modified >> path1 &&
+	echo modified >>path1 &&
 	git commit -am modified &&
 	git repack -adf &&
 	rcvpck="git receive-pack --reject-thin-pack-for-testing" &&

From 68c871fa56788f48c432d900883cd154083de2a3 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sat, 12 Sep 2015 12:25:47 +0200
Subject: [PATCH 051/259] t3701: verify that we can add *lots* of files
 interactively

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t3701-add-interactive.sh | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/t/t3701-add-interactive.sh b/t/t3701-add-interactive.sh
index 9a48933cecf5ae..947bd21c67a943 100755
--- a/t/t3701-add-interactive.sh
+++ b/t/t3701-add-interactive.sh
@@ -1119,6 +1119,27 @@ test_expect_success 'checkout -p patch editing of added file' '
 	)
 '
 
+test_expect_success EXPENSIVE 'add -i with a lot of files' '
+	git reset --hard &&
+	x160=0123456789012345678901234567890123456789 &&
+	x160=$x160$x160$x160$x160 &&
+	y= &&
+	i=0 &&
+	while test $i -le 200
+	do
+		name=$(printf "%s%03d" $x160 $i) &&
+		echo $name >$name &&
+		git add -N $name &&
+		y="${y}y$LF" &&
+		i=$(($i+1)) ||
+		exit 1
+	done &&
+	echo "$y" | git add -p -- . &&
+	git diff --cached >staged &&
+	test_line_count = 1407 staged &&
+	git reset --hard
+'
+
 test_expect_success 'show help from add--helper' '
 	git reset --hard &&
 	cat >expect <<-EOF &&

From d0963a2d5292b90b5bc3381c1f8ad8d911f947ed Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Tue, 30 Mar 2021 14:25:31 -0400
Subject: [PATCH 052/259] clink.pl: fix libexpatd.lib link error when using
 MSVC

When building with `make MSVC=1 DEBUG=1`, link to `libexpatd.lib`
rather than `libexpat.lib`.

It appears that the `vcpkg` package for "libexpat" has changed and now
creates `libexpatd.lib` for debug mode builds.  Previously, both debug
and release builds created a ".lib" with the same basename.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 compat/vcbuild/scripts/clink.pl | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/compat/vcbuild/scripts/clink.pl b/compat/vcbuild/scripts/clink.pl
index 3bd824154be381..2768ae15f1879f 100755
--- a/compat/vcbuild/scripts/clink.pl
+++ b/compat/vcbuild/scripts/clink.pl
@@ -66,7 +66,11 @@
 		}
 		push(@args, $lib);
 	} elsif ("$arg" eq "-lexpat") {
+	    if ($is_debug) {
+		push(@args, "libexpatd.lib");
+	    } else {
 		push(@args, "libexpat.lib");
+	    }
 	} elsif ("$arg" =~ /^-L/ && "$arg" ne "-LTCG") {
 		$arg =~ s/^-L/-LIBPATH:/;
 		push(@lflags, $arg);

From 347d2d32d10b096579faad7ea740e4e8b9874de6 Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Mon, 5 Apr 2021 15:27:38 -0400
Subject: [PATCH 053/259] Makefile: clean up .ilk files when MSVC=1

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 Makefile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Makefile b/Makefile
index d6479092a0b8df..51ec3ae131873d 100644
--- a/Makefile
+++ b/Makefile
@@ -3734,12 +3734,15 @@ ifdef MSVC
 	$(RM) $(patsubst %.o,%.o.pdb,$(OBJECTS))
 	$(RM) headless-git.o.pdb
 	$(RM) $(patsubst %.exe,%.pdb,$(OTHER_PROGRAMS))
+	$(RM) $(patsubst %.exe,%.ilk,$(OTHER_PROGRAMS))
 	$(RM) $(patsubst %.exe,%.iobj,$(OTHER_PROGRAMS))
 	$(RM) $(patsubst %.exe,%.ipdb,$(OTHER_PROGRAMS))
 	$(RM) $(patsubst %.exe,%.pdb,$(PROGRAMS))
+	$(RM) $(patsubst %.exe,%.ilk,$(PROGRAMS))
 	$(RM) $(patsubst %.exe,%.iobj,$(PROGRAMS))
 	$(RM) $(patsubst %.exe,%.ipdb,$(PROGRAMS))
 	$(RM) $(patsubst %.exe,%.pdb,$(TEST_PROGRAMS))
+	$(RM) $(patsubst %.exe,%.ilk,$(TEST_PROGRAMS))
 	$(RM) $(patsubst %.exe,%.iobj,$(TEST_PROGRAMS))
 	$(RM) $(patsubst %.exe,%.ipdb,$(TEST_PROGRAMS))
 	$(RM) compat/vcbuild/MSVC-DEFS-GEN

From c6ee424c10b826b7cb81f33f9b0c6d882b4d3838 Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Mon, 5 Apr 2021 14:08:22 -0400
Subject: [PATCH 054/259] vcbuild: add support for compiling Windows resource
 files

Create a wrapper for the Windows Resource Compiler (RC.EXE)
for use by the MSVC=1 builds. This is similar to the CL.EXE
and LIB.EXE wrappers used for the MSVC=1 builds.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 compat/vcbuild/find_vs_env.bat |  7 ++++++
 compat/vcbuild/scripts/rc.pl   | 46 ++++++++++++++++++++++++++++++++++
 config.mak.uname               |  3 ++-
 3 files changed, 55 insertions(+), 1 deletion(-)
 create mode 100644 compat/vcbuild/scripts/rc.pl

diff --git a/compat/vcbuild/find_vs_env.bat b/compat/vcbuild/find_vs_env.bat
index b35d264c0e6bed..379b16296e09c2 100644
--- a/compat/vcbuild/find_vs_env.bat
+++ b/compat/vcbuild/find_vs_env.bat
@@ -99,6 +99,7 @@ REM ================================================================
 
    SET sdk_dir=%WindowsSdkDir%
    SET sdk_ver=%WindowsSDKVersion%
+   SET sdk_ver_bin_dir=%WindowsSdkVerBinPath%%tgt%
    SET si=%sdk_dir%Include\%sdk_ver%
    SET sdk_includes=-I"%si%ucrt" -I"%si%um" -I"%si%shared"
    SET sl=%sdk_dir%lib\%sdk_ver%
@@ -130,6 +131,7 @@ REM ================================================================
 
    SET sdk_dir=%WindowsSdkDir%
    SET sdk_ver=%WindowsSDKVersion%
+   SET sdk_ver_bin_dir=%WindowsSdkVerBinPath%bin\amd64
    SET si=%sdk_dir%Include\%sdk_ver%
    SET sdk_includes=-I"%si%ucrt" -I"%si%um" -I"%si%shared" -I"%si%winrt"
    SET sl=%sdk_dir%lib\%sdk_ver%
@@ -160,6 +162,11 @@ REM ================================================================
    echo msvc_includes=%msvc_includes%
    echo msvc_libs=%msvc_libs%
 
+   echo sdk_ver_bin_dir=%sdk_ver_bin_dir%
+   SET X1=%sdk_ver_bin_dir:C:=/C%
+   SET X2=%X1:\=/%
+   echo sdk_ver_bin_dir_msys=%X2%
+
    echo sdk_includes=%sdk_includes%
    echo sdk_libs=%sdk_libs%
 
diff --git a/compat/vcbuild/scripts/rc.pl b/compat/vcbuild/scripts/rc.pl
new file mode 100644
index 00000000000000..7bca4cd81c6c63
--- /dev/null
+++ b/compat/vcbuild/scripts/rc.pl
@@ -0,0 +1,46 @@
+#!/usr/bin/perl -w
+######################################################################
+# Compile Resources on Windows
+#
+# This is a wrapper to facilitate the compilation of Git with MSVC
+# using GNU Make as the build system. So, instead of manipulating the
+# Makefile into something nasty, just to support non-space arguments
+# etc, we use this wrapper to fix the command line options
+#
+######################################################################
+use strict;
+my @args = ();
+my @input = ();
+
+while (@ARGV) {
+	my $arg = shift @ARGV;
+	if ("$arg" =~ /^-[dD]/) {
+		# GIT_VERSION gets passed with too many
+		# layers of dquote escaping.
+		$arg =~ s/\\"/"/g;
+
+		push(@args, $arg);
+
+	} elsif ("$arg" eq "-i") {
+		my $arg = shift @ARGV;
+		# TODO complain if NULL or is dashed ??
+		push(@input, $arg);
+
+	} elsif ("$arg" eq "-o") {
+		my $arg = shift @ARGV;
+		# TODO complain if NULL or is dashed ??
+		push(@args, "-fo$arg");
+
+	} else {
+		push(@args, $arg);
+	}
+}
+
+push(@args, "-nologo");
+push(@args, "-v");
+push(@args, @input);
+
+unshift(@args, "rc.exe");
+printf("**** @args\n");
+
+exit (system(@args) != 0);
diff --git a/config.mak.uname b/config.mak.uname
index c69e98b30866b1..a94cdb9cb98991 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -441,7 +441,7 @@ ifeq ($(uname_S),Windows)
 	# link.exe next to, and required by, cl.exe, we have to prepend this
 	# onto the existing $PATH.
 	#
-	SANE_TOOL_PATH ?= $(msvc_bin_dir_msys)
+	SANE_TOOL_PATH ?= $(msvc_bin_dir_msys):$(sdk_ver_bin_dir_msys)
 	HAVE_ALLOCA_H = YesPlease
 	NO_PREAD = YesPlease
 	NEEDS_CRYPTO_WITH_SSL = YesPlease
@@ -509,6 +509,7 @@ endif
 	# See https://msdn.microsoft.com/en-us/library/ms235330.aspx
 	EXTLIBS = user32.lib advapi32.lib shell32.lib wininet.lib ws2_32.lib invalidcontinue.obj kernel32.lib ntdll.lib
 	PTHREAD_LIBS =
+	RC = compat/vcbuild/scripts/rc.pl
 	lib =
 	BASIC_CFLAGS += $(vcpkg_inc) $(sdk_includes) $(msvc_includes)
 ifndef DEBUG

From 3f1f131c44f70c668ceef0e90b5c59eaed1c39ff Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Mon, 5 Apr 2021 14:12:14 -0400
Subject: [PATCH 055/259] config.mak.uname: add git.rc to MSVC builds

Teach MSVC=1 builds to depend on the `git.rc` file so that
the resulting executables have Windows-style resources and
version number information within them.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 config.mak.uname | 1 +
 1 file changed, 1 insertion(+)

diff --git a/config.mak.uname b/config.mak.uname
index a94cdb9cb98991..89404a7886e919 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -508,6 +508,7 @@ endif
 	# handle twice, or to access the osfhandle of an already-closed stdout
 	# See https://msdn.microsoft.com/en-us/library/ms235330.aspx
 	EXTLIBS = user32.lib advapi32.lib shell32.lib wininet.lib ws2_32.lib invalidcontinue.obj kernel32.lib ntdll.lib
+	GITLIBS += git.res
 	PTHREAD_LIBS =
 	RC = compat/vcbuild/scripts/rc.pl
 	lib =

From 3a12e6d7320d94e87dd508ece6fc86c523f9252e Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Mon, 5 Apr 2021 14:24:52 -0400
Subject: [PATCH 056/259] clink.pl: ignore no-stack-protector arg on MSVC=1
 builds

Ignore the `-fno-stack-protector` compiler argument when building
with MSVC.  This will be used in a later commit that needs to build
a Win32 GUI app.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 compat/vcbuild/scripts/clink.pl | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compat/vcbuild/scripts/clink.pl b/compat/vcbuild/scripts/clink.pl
index 2768ae15f1879f..73c8a2b184f38b 100755
--- a/compat/vcbuild/scripts/clink.pl
+++ b/compat/vcbuild/scripts/clink.pl
@@ -122,6 +122,8 @@
 		push(@cflags, "-wd4996");
 	} elsif ("$arg" =~ /^-W[a-z]/) {
 		# let's ignore those
+	} elsif ("$arg" eq "-fno-stack-protector") {
+		# eat this
 	} else {
 		push(@args, $arg);
 	}

From c7efa0430a44626e0c8b78f90392a1982ec554b2 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 2 Jul 2020 16:35:05 +0200
Subject: [PATCH 057/259] git add -i: handle CR/LF line endings in the
 interactive input

As of Git for Windows v2.27.0, there is an option to use Windows'
newly-introduced Pseudo Console support. When running an interactive add
operation with this support enabled, Git will receive CR/LF line
endings.

Therefore, let's not pretend that we are expecting Unix line endings.

This fixes https://github.com/git-for-windows/git/issues/2729

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 prompt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/prompt.c b/prompt.c
index 8935fe4dfb9414..cfce7e15a091a7 100644
--- a/prompt.c
+++ b/prompt.c
@@ -78,7 +78,7 @@ int git_read_line_interactively(struct strbuf *line)
 	int ret;
 
 	fflush(stdout);
-	ret = strbuf_getline_lf(line, stdin);
+	ret = strbuf_getline(line, stdin);
 	if (ret != EOF)
 		strbuf_trim_trailing_newline(line);
 

From 96f3555dd5f2177ebe8d2496007111cff5481505 Mon Sep 17 00:00:00 2001
From: Luke Bonanomi <lbonanomi@gmail.com>
Date: Wed, 24 Jun 2020 07:45:52 -0400
Subject: [PATCH 058/259] commit: accept "scissors" with CR/LF line endings

This change enhances `git commit --cleanup=scissors` by detecting
scissors lines ending in either LF (UNIX-style) or CR/LF (DOS-style).

Regression tests are included to specifically test for trailing
comments after a CR/LF-terminated scissors line.

Signed-off-by: Luke Bonanomi <lbonanomi@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t7502-commit-porcelain.sh | 42 +++++++++++++++++++++++++++++++++++++
 wt-status.c                 | 13 +++++++++---
 2 files changed, 52 insertions(+), 3 deletions(-)

diff --git a/t/t7502-commit-porcelain.sh b/t/t7502-commit-porcelain.sh
index b37e2018a74a7b..c38b96b66cd20a 100755
--- a/t/t7502-commit-porcelain.sh
+++ b/t/t7502-commit-porcelain.sh
@@ -623,6 +623,48 @@ test_expect_success 'cleanup commit messages (scissors option,-F,-e, scissors on
 	test_must_be_empty actual
 '
 
+test_expect_success 'helper-editor' '
+
+	write_script lf-to-crlf.sh <<-\EOF
+	sed "s/\$/Q/" <"$1" | tr Q "\\015" >"$1".new &&
+	mv -f "$1".new "$1"
+	EOF
+'
+
+test_expect_success 'cleanup commit messages (scissors option,-F,-e, CR/LF line endings)' '
+
+	test_config core.editor "\"$PWD/lf-to-crlf.sh\"" &&
+	scissors="# ------------------------ >8 ------------------------" &&
+
+	test_write_lines >text \
+	"# Keep this comment" "" " $scissors" \
+	"# Keep this comment, too" "$scissors" \
+	"# Remove this comment" "$scissors" \
+	"Remove this comment, too" &&
+
+	test_write_lines >expect \
+	"# Keep this comment" "" " $scissors" \
+	"# Keep this comment, too" &&
+
+	git commit --cleanup=scissors -e -F text --allow-empty &&
+	git cat-file -p HEAD >raw &&
+	sed -e "1,/^\$/d" raw >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'cleanup commit messages (scissors option,-F,-e, scissors on first line, CR/LF line endings)' '
+
+	scissors="# ------------------------ >8 ------------------------" &&
+	test_write_lines >text \
+	"$scissors" \
+	"# Remove this comment and any following lines" &&
+	cp text /tmp/test2-text &&
+	git commit --cleanup=scissors -e -F text --allow-empty --allow-empty-message &&
+	git cat-file -p HEAD >raw &&
+	sed -e "1,/^\$/d" raw >actual &&
+	test_must_be_empty actual
+'
+
 test_expect_success 'cleanup commit messages (strip option,-F)' '
 
 	echo >>negative &&
diff --git a/wt-status.c b/wt-status.c
index b778eef989d5a8..e9b09675822440 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -38,7 +38,7 @@
 #define UF_DELAY_WARNING_IN_MS (2 * 1000)
 
 static const char cut_line[] =
-"------------------------ >8 ------------------------\n";
+"------------------------ >8 ------------------------";
 
 static char default_wt_status_colors[][COLOR_MAXLEN] = {
 	GIT_COLOR_NORMAL, /* WT_STATUS_HEADER */
@@ -1090,15 +1090,22 @@ static void wt_longstatus_print_other(struct wt_status *s,
 	status_printf_ln(s, GIT_COLOR_NORMAL, "%s", "");
 }
 
+static inline int starts_with_newline(const char *p)
+{
+    return *p == '\n' || (*p == '\r' && p[1] == '\n');
+}
+
 size_t wt_status_locate_end(const char *s, size_t len)
 {
 	const char *p;
 	struct strbuf pattern = STRBUF_INIT;
 
 	strbuf_addf(&pattern, "\n%s %s", comment_line_str, cut_line);
-	if (starts_with(s, pattern.buf + 1))
+	if (starts_with(s, pattern.buf + 1) &&
+	    starts_with_newline(s + pattern.len - 1))
 		len = 0;
-	else if ((p = strstr(s, pattern.buf))) {
+	else if ((p = strstr(s, pattern.buf)) &&
+		 starts_with_newline(p + pattern.len)) {
 		size_t newlen = p - s + 1;
 		if (newlen < len)
 			len = newlen;

From 2415aa8f48d7dc30422495cb9268799df642c13b Mon Sep 17 00:00:00 2001
From: Jens Glathe <jens.glathe@oldschoolsolutions.biz>
Date: Tue, 2 Jun 2020 12:12:25 +0200
Subject: [PATCH 059/259] t0014: fix indentation

For some reason, this test case was indented with 4 spaces instead of 1
horizontal tab. The other test cases in the same test script are fine.

Signed-off-by: Jens Glathe <jens.glathe@oldschoolsolutions.biz>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t0014-alias.sh | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/t/t0014-alias.sh b/t/t0014-alias.sh
index 854d59ec58c25a..30708146887d19 100755
--- a/t/t0014-alias.sh
+++ b/t/t0014-alias.sh
@@ -38,10 +38,10 @@ test_expect_success 'looping aliases - internal execution' '
 #'
 
 test_expect_success 'run-command formats empty args properly' '
-    test_must_fail env GIT_TRACE=1 git frotz a "" b " " c 2>actual.raw &&
-    sed -ne "/run_command:/s/.*trace: run_command: //p" actual.raw >actual &&
-    echo "git-frotz a '\'''\'' b '\'' '\'' c" >expect &&
-    test_cmp expect actual
+	test_must_fail env GIT_TRACE=1 git frotz a "" b " " c 2>actual.raw &&
+	sed -ne "/run_command:/s/.*trace: run_command: //p" actual.raw >actual &&
+	echo "git-frotz a '\'''\'' b '\'' '\'' c" >expect &&
+	test_cmp expect actual
 '
 
 test_expect_success 'tracing a shell alias with arguments shows trace of prepared command' '

From caaf8ac95ea82c53b656892a4e91e6eb82bfda93 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 12 Aug 2020 15:06:17 +0000
Subject: [PATCH 060/259] git-gui: accommodate for intent-to-add files

As of Git v2.28.0, the diff for files staged via `git add -N` marks them
as new files. Git GUI was ill-prepared for that, and this patch teaches
Git GUI about them.

Please note that this will not even fix things with v2.28.0, as the
`rp/apply-cached-with-i-t-a` patches are required on Git's side, too.

This fixes https://github.com/git-for-windows/git/issues/2779

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Pratyush Yadav <me@yadavpratyush.com>
---
 git-gui/git-gui.sh   |  2 ++
 git-gui/lib/diff.tcl | 12 ++++++++----
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/git-gui/git-gui.sh b/git-gui/git-gui.sh
index 8fe7538e72084d..9f2ea858edb594 100755
--- a/git-gui/git-gui.sh
+++ b/git-gui/git-gui.sh
@@ -2079,6 +2079,7 @@ set all_icons(U$ui_index)   file_merge
 set all_icons(T$ui_index)   file_statechange
 
 set all_icons(_$ui_workdir) file_plain
+set all_icons(A$ui_workdir) file_plain
 set all_icons(M$ui_workdir) file_mod
 set all_icons(D$ui_workdir) file_question
 set all_icons(U$ui_workdir) file_merge
@@ -2105,6 +2106,7 @@ foreach i {
 		{A_ {mc "Staged for commit"}}
 		{AM {mc "Portions staged for commit"}}
 		{AD {mc "Staged for commit, missing"}}
+		{AA {mc "Intended to be added"}}
 
 		{_D {mc "Missing"}}
 		{D_ {mc "Staged for removal"}}
diff --git a/git-gui/lib/diff.tcl b/git-gui/lib/diff.tcl
index 871ad488c2a1c0..36d3715f7b25a2 100644
--- a/git-gui/lib/diff.tcl
+++ b/git-gui/lib/diff.tcl
@@ -582,7 +582,8 @@ proc apply_or_revert_hunk {x y revert} {
 	if {$current_diff_side eq $ui_index} {
 		set failed_msg [mc "Failed to unstage selected hunk."]
 		lappend apply_cmd --reverse --cached
-		if {[string index $mi 0] ne {M}} {
+		set file_state [string index $mi 0]
+		if {$file_state ne {M} && $file_state ne {A}} {
 			unlock_index
 			return
 		}
@@ -595,7 +596,8 @@ proc apply_or_revert_hunk {x y revert} {
 			lappend apply_cmd --cached
 		}
 
-		if {[string index $mi 1] ne {M}} {
+		set file_state [string index $mi 1]
+		if {$file_state ne {M} && $file_state ne {A}} {
 			unlock_index
 			return
 		}
@@ -687,7 +689,8 @@ proc apply_or_revert_range_or_line {x y revert} {
 		set failed_msg [mc "Failed to unstage selected line."]
 		set to_context {+}
 		lappend apply_cmd --reverse --cached
-		if {[string index $mi 0] ne {M}} {
+		set file_state [string index $mi 0]
+		if {$file_state ne {M} && $file_state ne {A}} {
 			unlock_index
 			return
 		}
@@ -702,7 +705,8 @@ proc apply_or_revert_range_or_line {x y revert} {
 			lappend apply_cmd --cached
 		}
 
-		if {[string index $mi 1] ne {M}} {
+		set file_state [string index $mi 1]
+		if {$file_state ne {M} && $file_state ne {A}} {
 			unlock_index
 			return
 		}

From 3a2a268a2072097fa3673fb5d401f059e875a7c0 Mon Sep 17 00:00:00 2001
From: Ian Bearman <ianb@microsoft.com>
Date: Fri, 31 Jan 2020 15:37:27 -0800
Subject: [PATCH 061/259] vcxproj: support building Windows/ARM64 binaries

Signed-off-by: Ian Bearman <ianb@microsoft.com>
Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 contrib/buildsystems/Generators/Vcxproj.pm | 23 ++++++++++++++++++++--
 1 file changed, 21 insertions(+), 2 deletions(-)

diff --git a/contrib/buildsystems/Generators/Vcxproj.pm b/contrib/buildsystems/Generators/Vcxproj.pm
index b2e68a16715e39..f9db773fdbb6cb 100644
--- a/contrib/buildsystems/Generators/Vcxproj.pm
+++ b/contrib/buildsystems/Generators/Vcxproj.pm
@@ -114,12 +114,21 @@ sub createProject {
       <Configuration>Release</Configuration>
       <Platform>x64</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
   </ItemGroup>
   <PropertyGroup Label="Globals">
     <ProjectGuid>$uuid</ProjectGuid>
     <Keyword>Win32Proj</Keyword>
     <VCPKGArch Condition="'\$(Platform)'=='Win32'">x86-windows</VCPKGArch>
-    <VCPKGArch Condition="'\$(Platform)'!='Win32'">x64-windows</VCPKGArch>
+    <VCPKGArch Condition="'\$(Platform)'=='x64'">x64-windows</VCPKGArch>
+    <VCPKGArch Condition="'\$(Platform)'=='ARM64'">arm64-windows</VCPKGArch>
     <VCPKGArchDirectory>$cdup\\compat\\vcbuild\\vcpkg\\installed\\\$(VCPKGArch)</VCPKGArchDirectory>
     <VCPKGBinDirectory Condition="'\$(Configuration)'=='Debug'">\$(VCPKGArchDirectory)\\debug\\bin</VCPKGBinDirectory>
     <VCPKGLibDirectory Condition="'\$(Configuration)'=='Debug'">\$(VCPKGArchDirectory)\\debug\\lib</VCPKGLibDirectory>
@@ -140,7 +149,7 @@ sub createProject {
   </PropertyGroup>
   <PropertyGroup>
     <ConfigurationType>$config_type</ConfigurationType>
-    <PlatformToolset>v140</PlatformToolset>
+    <PlatformToolset>v142</PlatformToolset>
     <!-- <CharacterSet>UTF-8</CharacterSet> -->
     <OutDir>..\\</OutDir>
     <!-- <IntDir>\$(ProjectDir)\$(Configuration)\\</IntDir> -->
@@ -355,8 +364,10 @@ sub createGlueProject {
     print F << "EOM";
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|ARM64 = Debug|ARM64
 		Debug|x64 = Debug|x64
 		Debug|x86 = Debug|x86
+		Release|ARM64 = Release|ARM64
 		Release|x64 = Release|x64
 		Release|x86 = Release|x86
 	EndGlobalSection
@@ -367,10 +378,14 @@ EOM
     foreach (@apps) {
         my $appname = $_;
         my $uuid = $build_structure{"APPS_${appname}_GUID"};
+        print F "\t\t${uuid}.Debug|ARM64.ActiveCfg = Debug|ARM64\n";
+        print F "\t\t${uuid}.Debug|ARM64.Build.0 = Debug|ARM64\n";
         print F "\t\t${uuid}.Debug|x64.ActiveCfg = Debug|x64\n";
         print F "\t\t${uuid}.Debug|x64.Build.0 = Debug|x64\n";
         print F "\t\t${uuid}.Debug|x86.ActiveCfg = Debug|Win32\n";
         print F "\t\t${uuid}.Debug|x86.Build.0 = Debug|Win32\n";
+        print F "\t\t${uuid}.Release|ARM64.ActiveCfg = Release|ARM64\n";
+        print F "\t\t${uuid}.Release|ARM64.Build.0 = Release|ARM64\n";
         print F "\t\t${uuid}.Release|x64.ActiveCfg = Release|x64\n";
         print F "\t\t${uuid}.Release|x64.Build.0 = Release|x64\n";
         print F "\t\t${uuid}.Release|x86.ActiveCfg = Release|Win32\n";
@@ -379,10 +394,14 @@ EOM
     foreach (@libs) {
         my $libname = $_;
         my $uuid = $build_structure{"LIBS_${libname}_GUID"};
+        print F "\t\t${uuid}.Debug|ARM64.ActiveCfg = Debug|ARM64\n";
+        print F "\t\t${uuid}.Debug|ARM64.Build.0 = Debug|ARM64\n";
         print F "\t\t${uuid}.Debug|x64.ActiveCfg = Debug|x64\n";
         print F "\t\t${uuid}.Debug|x64.Build.0 = Debug|x64\n";
         print F "\t\t${uuid}.Debug|x86.ActiveCfg = Debug|Win32\n";
         print F "\t\t${uuid}.Debug|x86.Build.0 = Debug|Win32\n";
+        print F "\t\t${uuid}.Release|ARM64.ActiveCfg = Release|ARM64\n";
+        print F "\t\t${uuid}.Release|ARM64.Build.0 = Release|ARM64\n";
         print F "\t\t${uuid}.Release|x64.ActiveCfg = Release|x64\n";
         print F "\t\t${uuid}.Release|x64.Build.0 = Release|x64\n";
         print F "\t\t${uuid}.Release|x86.ActiveCfg = Release|Win32\n";

From bbdb2e33316161c1f3d5ce7032ab4a87f49903b4 Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Mon, 5 Apr 2021 14:39:33 -0400
Subject: [PATCH 062/259] clink.pl: move default linker options for MSVC=1
 builds

Move the default `-ENTRY` and `-SUBSYSTEM` arguments for
MSVC=1 builds from `config.mak.uname` into `clink.pl`.
These args are constant for console-mode executables.

Add support to `clink.pl` for generating a Win32 GUI application
using the `-mwindows` argument (to match how GCC does it).  This
changes the `-ENTRY` and `-SUBSYSTEM` arguments accordingly.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 compat/vcbuild/scripts/clink.pl | 11 +++++++++++
 config.mak.uname                |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/compat/vcbuild/scripts/clink.pl b/compat/vcbuild/scripts/clink.pl
index 73c8a2b184f38b..a38b360015ece9 100755
--- a/compat/vcbuild/scripts/clink.pl
+++ b/compat/vcbuild/scripts/clink.pl
@@ -15,6 +15,7 @@
 my @lflags = ();
 my $is_linking = 0;
 my $is_debug = 0;
+my $is_gui = 0;
 while (@ARGV) {
 	my $arg = shift @ARGV;
 	if ("$arg" eq "-DDEBUG") {
@@ -124,11 +125,21 @@
 		# let's ignore those
 	} elsif ("$arg" eq "-fno-stack-protector") {
 		# eat this
+	} elsif ("$arg" eq "-mwindows") {
+		$is_gui = 1;
 	} else {
 		push(@args, $arg);
 	}
 }
 if ($is_linking) {
+	if ($is_gui) {
+		push(@args, "-ENTRY:wWinMainCRTStartup");
+		push(@args, "-SUBSYSTEM:WINDOWS");
+	} else {
+		push(@args, "-ENTRY:wmainCRTStartup");
+		push(@args, "-SUBSYSTEM:CONSOLE");
+	}
+
 	push(@args, @lflags);
 	unshift(@args, "link.exe");
 } else {
diff --git a/config.mak.uname b/config.mak.uname
index 89404a7886e919..d9d750251bc2b9 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -503,7 +503,7 @@ endif
 		compat/win32/trace2_win32_process_info.o \
 		compat/win32/dirent.o
 	COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DDETECT_MSYS_TTY -DENSURE_MSYSTEM_IS_SET -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
-	BASIC_LDFLAGS = -IGNORE:4217 -IGNORE:4049 -NOLOGO -ENTRY:wmainCRTStartup -SUBSYSTEM:CONSOLE
+	BASIC_LDFLAGS = -IGNORE:4217 -IGNORE:4049 -NOLOGO
 	# invalidcontinue.obj allows Git's source code to close the same file
 	# handle twice, or to access the osfhandle of an already-closed stdout
 	# See https://msdn.microsoft.com/en-us/library/ms235330.aspx

From e1cdf71fc8958d38274c908b9dced13ef731bfa1 Mon Sep 17 00:00:00 2001
From: Ian Bearman <ianb@microsoft.com>
Date: Fri, 31 Jan 2020 16:00:25 -0800
Subject: [PATCH 063/259] vcbuild: install ARM64 dependencies when building
 ARM64 binaries

Co-authored-by: Dennis Ameling <dennis@dennisameling.com>
Signed-off-by: Ian Bearman <ianb@microsoft.com>
Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/vcbuild/README                      | 6 +++++-
 compat/vcbuild/vcpkg_copy_dlls.bat         | 7 ++++++-
 compat/vcbuild/vcpkg_install.bat           | 9 +++++++--
 contrib/buildsystems/Generators/Vcxproj.pm | 2 +-
 4 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/compat/vcbuild/README b/compat/vcbuild/README
index 29ec1d0f104b80..1df1cabb1ebbbd 100644
--- a/compat/vcbuild/README
+++ b/compat/vcbuild/README
@@ -6,7 +6,11 @@ The Steps to Build Git with VS2015 or VS2017 from the command line.
    Prompt or from an SDK bash window:
 
    $ cd <repo_root>
-   $ ./compat/vcbuild/vcpkg_install.bat
+   $ ./compat/vcbuild/vcpkg_install.bat x64-windows
+
+   or
+
+   $ ./compat/vcbuild/vcpkg_install.bat arm64-windows
 
    The vcpkg tools and all of the third-party sources will be installed
    in this folder:
diff --git a/compat/vcbuild/vcpkg_copy_dlls.bat b/compat/vcbuild/vcpkg_copy_dlls.bat
index 13661c14f8705c..8bea0cbf83b6cf 100644
--- a/compat/vcbuild/vcpkg_copy_dlls.bat
+++ b/compat/vcbuild/vcpkg_copy_dlls.bat
@@ -15,7 +15,12 @@ REM ================================================================
 	@FOR /F "delims=" %%D IN ("%~dp0") DO @SET cwd=%%~fD
 	cd %cwd%
 
-	SET arch=x64-windows
+	SET arch=%2
+	IF NOT DEFINED arch (
+		echo defaulting to 'x64-windows`. Invoke %0 with 'x86-windows', 'x64-windows', or 'arm64-windows'
+		set arch=x64-windows
+	)
+
 	SET inst=%cwd%vcpkg\installed\%arch%
 
 	IF [%1]==[release] (
diff --git a/compat/vcbuild/vcpkg_install.bat b/compat/vcbuild/vcpkg_install.bat
index 8330d8120fb511..cacef18c11dc79 100644
--- a/compat/vcbuild/vcpkg_install.bat
+++ b/compat/vcbuild/vcpkg_install.bat
@@ -31,6 +31,12 @@ REM ================================================================
 
 	SETLOCAL EnableDelayedExpansion
 
+	SET arch=%1
+	IF NOT DEFINED arch (
+		echo defaulting to 'x64-windows`. Invoke %0 with 'x86-windows', 'x64-windows', or 'arm64-windows'
+		set arch=x64-windows
+	)
+
 	@FOR /F "delims=" %%D IN ("%~dp0") DO @SET cwd=%%~fD
 	cd %cwd%
 
@@ -55,9 +61,8 @@ REM ================================================================
 	echo Successfully installed %cwd%vcpkg\vcpkg.exe
 
 :install_libraries
-	SET arch=x64-windows
 
-	echo Installing third-party libraries...
+	echo Installing third-party libraries(%arch%)...
 	FOR %%i IN (zlib expat libiconv openssl libssh2 curl) DO (
 	    cd %cwd%vcpkg
 	    IF NOT EXIST "packages\%%i_%arch%" CALL :sub__install_one %%i
diff --git a/contrib/buildsystems/Generators/Vcxproj.pm b/contrib/buildsystems/Generators/Vcxproj.pm
index f9db773fdbb6cb..dc32493f91bf7f 100644
--- a/contrib/buildsystems/Generators/Vcxproj.pm
+++ b/contrib/buildsystems/Generators/Vcxproj.pm
@@ -193,7 +193,7 @@ EOM
     <PreBuildEvent Condition="!Exists('$cdup\\compat\\vcbuild\\vcpkg\\installed\\\$(VCPKGArch)\\include\\openssl\\ssl.h')">
       <Message>Initialize VCPKG</Message>
       <Command>del "$cdup\\compat\\vcbuild\\vcpkg"</Command>
-      <Command>call "$cdup\\compat\\vcbuild\\vcpkg_install.bat"</Command>
+      <Command>call "$cdup\\compat\\vcbuild\\vcpkg_install.bat" \$(VCPKGArch)</Command>
     </PreBuildEvent>
 EOM
     }

From 5dcf680da73a284f7c92385dd2e234defa7fea89 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 7 Apr 2021 15:29:21 +0200
Subject: [PATCH 064/259] buildsystems: remove duplicate clause

This seems to have been there since 259d87c35495 (Add scripts to
generate projects for other buildsystems (MSVC vcproj, QMake),
2009-09-16), i.e. since the beginning of that file.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 contrib/buildsystems/engine.pl | 1 -
 1 file changed, 1 deletion(-)

diff --git a/contrib/buildsystems/engine.pl b/contrib/buildsystems/engine.pl
index 069be7e4befcd7..4243784e8a6b6e 100755
--- a/contrib/buildsystems/engine.pl
+++ b/contrib/buildsystems/engine.pl
@@ -265,7 +265,6 @@ sub handleCompileLine
             shift @parts;
         } elsif ("$part" eq "-c") {
             # ignore compile flag
-        } elsif ("$part" eq "-c") {
         } elsif ($part =~ /^.?-I/) {
             push(@incpaths, $part);
         } elsif ($part =~ /^.?-D/) {

From e63298f0b7de37f485a89ba3d65f8a4306e9fc19 Mon Sep 17 00:00:00 2001
From: Ian Bearman <ianb@microsoft.com>
Date: Tue, 4 Feb 2020 10:34:40 -0800
Subject: [PATCH 065/259] vcbuild: add an option to install individual
 'features'

In this context, a "feature" is a dependency combined with its own
dependencies.

Signed-off-by: Ian Bearman <ianb@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/vcbuild/vcpkg_install.bat | 35 +++++++++++++++++++++++++++++++-
 1 file changed, 34 insertions(+), 1 deletion(-)

diff --git a/compat/vcbuild/vcpkg_install.bat b/compat/vcbuild/vcpkg_install.bat
index cacef18c11dc79..8da212487ae97d 100644
--- a/compat/vcbuild/vcpkg_install.bat
+++ b/compat/vcbuild/vcpkg_install.bat
@@ -85,14 +85,47 @@ REM ================================================================
 :sub__install_one
 	echo     Installing package %1...
 
+	call :%1_features
+
 	REM vcpkg may not be reliable on slow, intermittent or proxy
 	REM connections, see e.g.
 	REM https://social.msdn.microsoft.com/Forums/windowsdesktop/en-US/4a8f7be5-5e15-4213-a7bb-ddf424a954e6/winhttpsendrequest-ends-with-12002-errorhttptimeout-after-21-seconds-no-matter-what-timeout?forum=windowssdk
 	REM which explains the hidden 21 second timeout
 	REM (last post by Dave : Microsoft - Windows Networking team)
 
-	.\vcpkg.exe install %1:%arch%
+	.\vcpkg.exe install %1%features%:%arch%
 	IF ERRORLEVEL 1 ( EXIT /B 1 )
 
 	echo     Finished %1
 	goto :EOF
+
+::
+:: features for each vcpkg to install
+:: there should be an entry here for each package to install
+:: 'set features=' means use the default otherwise
+:: 'set features=[comma-delimited-feature-set]' is the syntax
+::
+
+:zlib_features
+set features=
+goto :EOF
+
+:expat_features
+set features=
+goto :EOF
+
+:libiconv_features
+set features=
+goto :EOF
+
+:openssl_features
+set features=
+goto :EOF
+
+:libssh2_features
+set features=
+goto :EOF
+
+:curl_features
+set features=[core,openssl]
+goto :EOF

From e7b1310a82c1b0e975a8fd317f4d5196882e4c03 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 7 Apr 2021 15:15:08 +0200
Subject: [PATCH 066/259] vcxproj: handle resource files, too

On Windows, we also compile a "resource" file, which is similar to
source code, but contains metadata (such as the program version).

So far, we did not compile it in `MSVC` mode, only when compiling Git
for Windows with the GNU C Compiler.

In preparation for including it also when compiling with MS Visual C,
let's teach our `vcxproj` generator to handle those sort of files, too.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 contrib/buildsystems/Generators/Vcxproj.pm | 17 ++++++++++++++++-
 contrib/buildsystems/engine.pl             |  9 +++++----
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/contrib/buildsystems/Generators/Vcxproj.pm b/contrib/buildsystems/Generators/Vcxproj.pm
index 0439b82f55e243..5e97f2ff99d344 100644
--- a/contrib/buildsystems/Generators/Vcxproj.pm
+++ b/contrib/buildsystems/Generators/Vcxproj.pm
@@ -89,6 +89,9 @@ sub createProject {
     $defines =~ s/>/&gt;/g;
     $defines =~ s/\'//g;
 
+    my $rcdefines = $defines;
+    $rcdefines =~ s/(?<!\\)"/\\$&/g;
+
     my $dir = $vcxproj;
     $dir =~ s/\/[^\/]*$//;
     die "Could not create the directory $dir for $label project!\n" unless (-d "$dir" || mkdir "$dir");
@@ -203,6 +206,9 @@ EOM
       <PreprocessorDefinitions>WIN32;_DEBUG;$defines;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
     </ClCompile>
+    <ResourceCompile>
+      <PreprocessorDefinitions>WIN32;_DEBUG;$rcdefines;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+    </ResourceCompile>
     <Link>
       <GenerateDebugInformation>true</GenerateDebugInformation>
     </Link>
@@ -216,6 +222,9 @@ EOM
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <FavorSizeOrSpeed>Speed</FavorSizeOrSpeed>
     </ClCompile>
+    <ResourceCompile>
+      <PreprocessorDefinitions>WIN32;NDEBUG;$rcdefines;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+    </ResourceCompile>
     <Link>
       <GenerateDebugInformation>true</GenerateDebugInformation>
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
@@ -225,9 +234,15 @@ EOM
   <ItemGroup>
 EOM
     foreach(@sources) {
-        print F << "EOM";
+        if (/\.rc$/) {
+            print F << "EOM";
+    <ResourceCompile Include="$_" />
+EOM
+        } else {
+            print F << "EOM";
     <ClCompile Include="$_" />
 EOM
+        }
     }
     print F << "EOM";
   </ItemGroup>
diff --git a/contrib/buildsystems/engine.pl b/contrib/buildsystems/engine.pl
index 4243784e8a6b6e..82849812212efc 100755
--- a/contrib/buildsystems/engine.pl
+++ b/contrib/buildsystems/engine.pl
@@ -165,7 +165,7 @@ sub parseMakeOutput
             next;
         }
 
-        if($text =~ / -c /) {
+        if($text =~ / -c / || $text =~ / -i \S+\.rc /) {
             # compilation
             handleCompileLine($text, $line);
 
@@ -263,7 +263,7 @@ sub handleCompileLine
         if ("$part" eq "-o") {
             # ignore object file
             shift @parts;
-        } elsif ("$part" eq "-c") {
+        } elsif ("$part" eq "-c" || "$part" eq "-i") {
             # ignore compile flag
         } elsif ($part =~ /^.?-I/) {
             push(@incpaths, $part);
@@ -271,7 +271,7 @@ sub handleCompileLine
             push(@defines, $part);
         } elsif ($part =~ /^-/) {
             push(@cflags, $part);
-        } elsif ($part =~ /\.(c|cc|cpp)$/) {
+        } elsif ($part =~ /\.(c|cc|cpp|rc)$/) {
             $sourcefile = $part;
         } else {
             die "Unhandled compiler option @ line $lineno: $part";
@@ -358,7 +358,7 @@ sub handleLinkLine
             push(@libs, $part);
         } elsif ($part eq 'invalidcontinue.obj') {
             # ignore - known to MSVC
-        } elsif ($part =~ /\.o$/) {
+        } elsif ($part =~ /\.(o|res)$/) {
             push(@objfiles, $part);
         } elsif ($part =~ /\.obj$/) {
             # do nothing, 'make' should not be producing .obj, only .o files
@@ -372,6 +372,7 @@ sub handleLinkLine
         my $sourcefile = $_;
         $sourcefile =~ s/^headless-git\.o$/compat\/win32\/headless.c/;
         $sourcefile =~ s/\.o$/.c/;
+        $sourcefile =~ s/\.res$/.rc/;
         push(@sources, $sourcefile);
         push(@cflags, @{$compile_options{"${sourcefile}_CFLAGS"}});
         push(@defines, @{$compile_options{"${sourcefile}_DEFINES"}});

From 99c4bdae84add03fc803c76d3bbea2e099e90747 Mon Sep 17 00:00:00 2001
From: Dennis Ameling <dennis@dennisameling.com>
Date: Fri, 4 Dec 2020 14:11:34 +0100
Subject: [PATCH 067/259] cmake: allow building for Windows/ARM64

Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 contrib/buildsystems/CMakeLists.txt | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index 832f46b316b764..fb1abbea219bde 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -65,9 +65,9 @@ if(USE_VCPKG)
 	set(VCPKG_DIR "${CMAKE_SOURCE_DIR}/compat/vcbuild/vcpkg")
 	if(NOT EXISTS ${VCPKG_DIR})
 		message("Initializing vcpkg and building the Git's dependencies (this will take a while...)")
-		execute_process(COMMAND ${CMAKE_SOURCE_DIR}/compat/vcbuild/vcpkg_install.bat)
+		execute_process(COMMAND ${CMAKE_SOURCE_DIR}/compat/vcbuild/vcpkg_install.bat ${VCPKG_ARCH})
 	endif()
-	list(APPEND CMAKE_PREFIX_PATH "${VCPKG_DIR}/installed/x64-windows")
+	list(APPEND CMAKE_PREFIX_PATH "${VCPKG_DIR}/installed/${VCPKG_ARCH}")
 
 	# In the vcpkg edition, we need this to be able to link to libcurl
 	set(CURL_NO_CURL_CMAKE ON)
@@ -1106,7 +1106,7 @@ file(APPEND ${CMAKE_BINARY_DIR}/GIT-BUILD-OPTIONS "RUNTIME_PREFIX='${RUNTIME_PRE
 file(APPEND ${CMAKE_BINARY_DIR}/GIT-BUILD-OPTIONS "NO_PYTHON='${NO_PYTHON}'\n")
 file(APPEND ${CMAKE_BINARY_DIR}/GIT-BUILD-OPTIONS "SUPPORTS_SIMPLE_IPC='${SUPPORTS_SIMPLE_IPC}'\n")
 if(USE_VCPKG)
-	file(APPEND ${CMAKE_BINARY_DIR}/GIT-BUILD-OPTIONS "PATH=\"$PATH:$TEST_DIRECTORY/../compat/vcbuild/vcpkg/installed/x64-windows/bin\"\n")
+	file(APPEND ${CMAKE_BINARY_DIR}/GIT-BUILD-OPTIONS "PATH=\"$PATH:$TEST_DIRECTORY/../compat/vcbuild/vcpkg/installed/${VCPKG_ARCH}/bin\"\n")
 endif()
 
 #Make the tests work when building out of the source tree

From 1f8310d1ca4ee5fb5305db5174b4068663fc9df6 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 7 Apr 2021 21:57:31 +0200
Subject: [PATCH 068/259] vcxproj: ignore -fno-stack-protector and -fno-common

An upcoming commit will introduce those compile options; MSVC does not
understand them, so let's suppress them when generating the Visual
Studio project files.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 contrib/buildsystems/engine.pl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/contrib/buildsystems/engine.pl b/contrib/buildsystems/engine.pl
index 82849812212efc..417ae71d44ccab 100755
--- a/contrib/buildsystems/engine.pl
+++ b/contrib/buildsystems/engine.pl
@@ -263,7 +263,7 @@ sub handleCompileLine
         if ("$part" eq "-o") {
             # ignore object file
             shift @parts;
-        } elsif ("$part" eq "-c" || "$part" eq "-i") {
+        } elsif ("$part" eq "-c" || "$part" eq "-i" || "$part" =~ /^-fno-/) {
             # ignore compile flag
         } elsif ($part =~ /^.?-I/) {
             push(@incpaths, $part);

From de509786483163470edceefc5deeafc3066f0642 Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.email>
Date: Sun, 6 Oct 2019 18:40:55 +0100
Subject: [PATCH 069/259] vcpkg_install: detect lack of Git

The vcpkg_install batch file depends on the availability of a
working Git on the CMD path. This may not be present if the user
has selected the 'bash only' option during Git-for-Windows install.

Detect and tell the user about their lack of a working Git in the CMD
window.

Fixes #2348.
A separate PR https://github.com/git-for-windows/build-extra/pull/258
now highlights the recommended path setting during install.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
---
 compat/vcbuild/vcpkg_install.bat | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/compat/vcbuild/vcpkg_install.bat b/compat/vcbuild/vcpkg_install.bat
index ebd0bad242a8ca..bcbbf536af3141 100644
--- a/compat/vcbuild/vcpkg_install.bat
+++ b/compat/vcbuild/vcpkg_install.bat
@@ -36,6 +36,13 @@ REM ================================================================
 
 	dir vcpkg\vcpkg.exe >nul 2>nul && GOTO :install_libraries
 
+	git.exe version 2>nul
+	IF ERRORLEVEL 1 (
+	echo "***"
+	echo "Git not found. Please adjust your CMD path or Git install option."
+	echo "***"
+	EXIT /B 1 )
+
 	echo Fetching vcpkg in %cwd%vcpkg
 	git.exe clone https://github.com/Microsoft/vcpkg vcpkg
 	IF ERRORLEVEL 1 ( EXIT /B 1 )

From abb12a3f44ea4e54df61e99862888bb44936a574 Mon Sep 17 00:00:00 2001
From: Dennis Ameling <dennis@dennisameling.com>
Date: Sun, 29 Nov 2020 00:12:26 +0100
Subject: [PATCH 070/259] ci(vs-build) also build Windows/ARM64 artifacts

There are no Windows/ARM64 agents in GitHub Actions yet, therefore we
just skip adjusting the `vs-test` job for now.

Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 .github/workflows/main.yml | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 916a64b6736d1c..a3a97088cd8380 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -169,8 +169,11 @@ jobs:
       NO_PERL: 1
       GIT_CONFIG_PARAMETERS: "'user.name=CI' 'user.email=ci@git'"
     runs-on: windows-latest
+    strategy:
+      matrix:
+        arch: [x64, arm64]
     concurrency:
-      group: vs-build-${{ github.ref }}
+      group: vs-build-${{ github.ref }}-${{ matrix.arch }}
       cancel-in-progress: ${{ needs.ci-config.outputs.skip_concurrent == 'yes' }}
     steps:
     - uses: actions/checkout@v4
@@ -189,14 +192,14 @@ jobs:
       uses: microsoft/setup-msbuild@v2
     - name: copy dlls to root
       shell: cmd
-      run: compat\vcbuild\vcpkg_copy_dlls.bat release
+      run: compat\vcbuild\vcpkg_copy_dlls.bat release ${{ matrix.arch }}-windows
     - name: generate Visual Studio solution
       shell: bash
       run: |
-        cmake `pwd`/contrib/buildsystems/ -DCMAKE_PREFIX_PATH=`pwd`/compat/vcbuild/vcpkg/installed/x64-windows \
-        -DNO_GETTEXT=YesPlease -DPERL_TESTS=OFF -DPYTHON_TESTS=OFF -DCURL_NO_CURL_CMAKE=ON
+        cmake `pwd`/contrib/buildsystems/ -DCMAKE_PREFIX_PATH=`pwd`/compat/vcbuild/vcpkg/installed/${{ matrix.arch }}-windows \
+        -DNO_GETTEXT=YesPlease -DPERL_TESTS=OFF -DPYTHON_TESTS=OFF -DCURL_NO_CURL_CMAKE=ON -DCMAKE_GENERATOR_PLATFORM=${{ matrix.arch }} -DVCPKG_ARCH=${{ matrix.arch }}-windows
     - name: MSBuild
-      run: msbuild git.sln -property:Configuration=Release -property:Platform=x64 -maxCpuCount:4 -property:PlatformToolset=v142
+      run: msbuild git.sln -property:Configuration=Release -property:Platform=${{ matrix.arch }} -maxCpuCount:4 -property:PlatformToolset=v142
     - name: bundle artifact tar
       shell: bash
       env:
@@ -210,7 +213,7 @@ jobs:
     - name: upload tracked files and build artifacts
       uses: actions/upload-artifact@v4
       with:
-        name: vs-artifacts
+        name: vs-artifacts-${{ matrix.arch }}
         path: artifacts
   vs-test:
     name: win+VS test
@@ -228,7 +231,7 @@ jobs:
     - name: download tracked files and build artifacts
       uses: actions/download-artifact@v4
       with:
-        name: vs-artifacts
+        name: vs-artifacts-x64
         path: ${{github.workspace}}
     - name: extract tracked files and build artifacts
       shell: bash

From 179e8ac8e2cd626bb1755f1ea7f52dd3dc7adc5d Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 7 Apr 2021 15:48:50 +0200
Subject: [PATCH 071/259] vcxproj: handle GUI programs, too

So far, we only built Console programs, but we are about to introduce a
program that targets the Windows subsystem (i.e. it is a so-called "GUI"
program).

Let's handle this preemptively in the script that generates the Visual
Studio files.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 contrib/buildsystems/Generators/Vcxproj.pm | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/contrib/buildsystems/Generators/Vcxproj.pm b/contrib/buildsystems/Generators/Vcxproj.pm
index 5e97f2ff99d344..a6d1c6b8d05682 100644
--- a/contrib/buildsystems/Generators/Vcxproj.pm
+++ b/contrib/buildsystems/Generators/Vcxproj.pm
@@ -92,6 +92,13 @@ sub createProject {
     my $rcdefines = $defines;
     $rcdefines =~ s/(?<!\\)"/\\$&/g;
 
+    my $entrypoint = 'wmainCRTStartup';
+    my $subsystem = 'Console';
+    if (grep /^-mwindows$/, @{$$build_structure{"$prefix${name}_LFLAGS"}}) {
+        $entrypoint = 'wWinMainCRTStartup';
+        $subsystem = 'Windows';
+    }
+
     my $dir = $vcxproj;
     $dir =~ s/\/[^\/]*$//;
     die "Could not create the directory $dir for $label project!\n" unless (-d "$dir" || mkdir "$dir");
@@ -179,9 +186,9 @@ sub createProject {
       <AdditionalLibraryDirectories>\$(VCPKGLibDirectory);%(AdditionalLibraryDirectories)</AdditionalLibraryDirectories>
       <AdditionalDependencies>\$(VCPKGLibs);\$(AdditionalDependencies)</AdditionalDependencies>
       <AdditionalOptions>invalidcontinue.obj %(AdditionalOptions)</AdditionalOptions>
-      <EntryPointSymbol>wmainCRTStartup</EntryPointSymbol>
+      <EntryPointSymbol>$entrypoint</EntryPointSymbol>
       <ManifestFile>$cdup\\compat\\win32\\git.manifest</ManifestFile>
-      <SubSystem>Console</SubSystem>
+      <SubSystem>$subsystem</SubSystem>
     </Link>
 EOM
     if ($target eq 'libgit') {

From 00848d088ba4201d19ed6e42c0efb75ffa2e7ed1 Mon Sep 17 00:00:00 2001
From: Yuyi Wang <Strawberry_Str@hotmail.com>
Date: Sat, 11 Mar 2023 17:51:18 +0800
Subject: [PATCH 072/259] cmake: install headless-git.

headless-git is a git executable without opening a console window. It is
useful when other GUI executables want to call git. We should install it
together with git on Windows.

Signed-off-by: Yuyi Wang <Strawberry_Str@hotmail.com>
---
 contrib/buildsystems/CMakeLists.txt | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index 832f46b316b764..5775c1c7bbdfad 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -740,6 +740,7 @@ if(WIN32)
 	endif()
 
 	add_executable(headless-git ${CMAKE_SOURCE_DIR}/compat/win32/headless.c)
+	list(APPEND PROGRAMS_BUILT headless-git)
 	if(CMAKE_C_COMPILER_ID STREQUAL "GNU" OR CMAKE_C_COMPILER_ID STREQUAL "Clang")
 		target_link_options(headless-git PUBLIC -municode -Wl,-subsystem,windows)
 	elseif(CMAKE_C_COMPILER_ID STREQUAL "MSVC")
@@ -919,7 +920,7 @@ list(TRANSFORM git_perl_scripts PREPEND "${CMAKE_BINARY_DIR}/")
 
 #install
 foreach(program ${PROGRAMS_BUILT})
-if(program MATCHES "^(git|git-shell|scalar)$")
+if(program MATCHES "^(git|git-shell|headless-git|scalar)$")
 install(TARGETS ${program}
 	RUNTIME DESTINATION bin)
 else()

From 12048b5647befc335c8dc955156a94614c1731df Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.email>
Date: Sun, 6 Oct 2019 18:43:57 +0100
Subject: [PATCH 073/259] vcpkg_install: add comment regarding slow network
 connections

The vcpkg downloads may not succeed. Warn careful readers of the time out.

A simple retry will usually resolve the issue.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/vcbuild/vcpkg_install.bat | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/compat/vcbuild/vcpkg_install.bat b/compat/vcbuild/vcpkg_install.bat
index bcbbf536af3141..8330d8120fb511 100644
--- a/compat/vcbuild/vcpkg_install.bat
+++ b/compat/vcbuild/vcpkg_install.bat
@@ -80,6 +80,12 @@ REM ================================================================
 :sub__install_one
 	echo     Installing package %1...
 
+	REM vcpkg may not be reliable on slow, intermittent or proxy
+	REM connections, see e.g.
+	REM https://social.msdn.microsoft.com/Forums/windowsdesktop/en-US/4a8f7be5-5e15-4213-a7bb-ddf424a954e6/winhttpsendrequest-ends-with-12002-errorhttptimeout-after-21-seconds-no-matter-what-timeout?forum=windowssdk
+	REM which explains the hidden 21 second timeout
+	REM (last post by Dave : Microsoft - Windows Networking team)
+
 	.\vcpkg.exe install %1:%arch%
 	IF ERRORLEVEL 1 ( EXIT /B 1 )
 

From 14b74598d056744095bc8749e96308183c183816 Mon Sep 17 00:00:00 2001
From: Dennis Ameling <dennis@dennisameling.com>
Date: Sun, 6 Dec 2020 18:39:26 +0100
Subject: [PATCH 074/259] Add schannel to curl installation

Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
---
 compat/vcbuild/vcpkg_install.bat | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compat/vcbuild/vcpkg_install.bat b/compat/vcbuild/vcpkg_install.bat
index 8da212487ae97d..575c65c20ba307 100644
--- a/compat/vcbuild/vcpkg_install.bat
+++ b/compat/vcbuild/vcpkg_install.bat
@@ -127,5 +127,5 @@ set features=
 goto :EOF
 
 :curl_features
-set features=[core,openssl]
+set features=[core,openssl,schannel]
 goto :EOF

From b38a487321a5aaa12062896637bd9b0e1d207eab Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.email>
Date: Fri, 2 Jul 2021 00:30:24 +0100
Subject: [PATCH 075/259] CMake: default Visual Studio generator has changed

Correct some wording and inform users regarding the Visual Studio
changes (from V16.6) to the default generator.

Subsequent commits ensure that Git for Windows can be directly
opened in modern Visual Studio without needing special configuration
of the CMakeLists settings.

It appeares that internally Visual Studio creates it's own version of the
.sln file (etc.) for extension tools that expect them.

The large number of references below document the shifting of Visual Studio
default and CMake setting options.

refs: https://docs.microsoft.com/en-us/search/?scope=C%2B%2B&view=msvc-150&terms=Ninja

1. https://docs.microsoft.com/en-us/cpp/linux/cmake-linux-configure?view=msvc-160
(note the linux bit)
 "In Visual Studio 2019 version 16.6 or later ***, Ninja is the default
generator for configurations targeting a remote system or WSL. For more
information, see this post on the C++ Team Blog
[https://devblogs.microsoft.com/cppblog/linux-development-with-visual-studio-first-class-support-for-gdbserver-improved-build-times-with-ninja-and-updates-to-the-connection-manager/].

For more information about these settings, see CMakeSettings.json reference
[https://docs.microsoft.com/en-us/cpp/build/cmakesettings-reference?view=msvc-160]."

2. https://docs.microsoft.com/en-us/cpp/build/cmake-presets-vs?view=msvc-160
"CMake supports two files that allow users to specify common configure,
build, and test options and share them with others: CMakePresets.json
and CMakeUserPresets.json."

" Both files are supported in Visual Studio 2019 version 16.10 or later.
***"
3. https://devblogs.microsoft.com/cppblog/linux-development-with-visual-studio-first-class-support-for-gdbserver-improved-build-times-with-ninja-and-updates-to-the-connection-manager/
" Ninja has been the default generator (underlying build system) for
CMake configurations targeting Windows for some time***, but in Visual
Studio 2019 version 16.6 Preview 3*** we added support for Ninja on Linux."

4. https://docs.microsoft.com/en-us/cpp/build/cmakesettings-reference?view=msvc-160
" `generator`: specifies CMake generator to use for this configuration.
May be one of:

    Visual Studio 2019 only:
        Visual Studio 16 2019
        Visual Studio 16 2019 Win64
        Visual Studio 16 2019 ARM

    Visual Studio 2017 and later:
        Visual Studio 15 2017
        Visual Studio 15 2017 Win64
        Visual Studio 15 2017 ARM
        Visual Studio 14 2015
        Visual Studio 14 2015 Win64
        Visual Studio 14 2015 ARM
        Unix Makefiles
        Ninja

Because Ninja is designed for fast build speeds instead of flexibility
and function, it is set as the default. However, some CMake projects may
be unable to correctly build using Ninja. If this occurs, you can
instruct CMake to generate Visual Studio projects instead.

To specify a Visual Studio generator in Visual Studio 2017, open the
settings editor from the main menu by choosing CMake | Change CMake
Settings. Delete "Ninja" and type "V". This activates IntelliSense,
which enables you to choose the generator you want."

"To specify a Visual Studio generator in Visual Studio 2019, right-click
on the CMakeLists.txt file in Solution Explorer and choose CMake
Settings for project > Show Advanced Settings > CMake Generator.

When the active configuration specifies a Visual Studio generator, by
default MSBuild.exe is invoked with` -m -v:minimal` arguments."

5. https://docs.microsoft.com/en-us/cpp/build/cmake-presets-vs?view=msvc-160#enable-cmakepresetsjson-integration-in-visual-studio-2019
"Enable CMakePresets.json integration in Visual Studio 2019

CMakePresets.json integration isn't enabled by default in Visual Studio
2019. You can enable it for all CMake projects in Tools > Options >
CMake > General: (tick a box)" ... see more.

6. https://docs.microsoft.com/en-us/cpp/build/cmakesettings-reference?view=msvc-140
(whichever v140 is..)
"CMake projects are supported in Visual Studio 2017 and later."

7. https://docs.microsoft.com/en-us/cpp/overview/what-s-new-for-cpp-2017?view=msvc-150
"Support added for the CMake Ninja generator."

8. https://docs.microsoft.com/en-us/cpp/overview/what-s-new-for-cpp-2017?view=msvc-150#cmake-support-via-open-folder
"CMake support via Open Folder
Visual Studio 2017 introduces support for using CMake projects without
converting to MSBuild project files (.vcxproj). For more information,
see CMake projects in Visual
Studio[https://docs.microsoft.com/en-us/cpp/build/cmake-projects-in-visual-studio?view=msvc-150].
Opening CMake projects with Open Folder automatically configures the
environment for C++ editing, building, and debugging." ... +more!

9. https://docs.microsoft.com/en-us/cpp/build/cmake-presets-vs?view=msvc-160#supported-cmake-and-cmakepresetsjson-versions
"Visual Studio reads and evaluates CMakePresets.json and
CMakeUserPresets.json itself and doesn't invoke CMake directly with the
--preset option. So, CMake version 3.20 or later isn't strictly required
when you're building with CMakePresets.json inside Visual Studio. We
recommend using CMake version 3.14 or later."

10. https://docs.microsoft.com/en-us/cpp/build/cmake-presets-vs?view=msvc-160#enable-cmakepresetsjson-integration-in-visual-studio-2019
"If you don't want to enable CMakePresets.json integration for all CMake
projects, you can enable CMakePresets.json integration for a single
CMake project by adding a CMakePresets.json file to the root of the open
folder. You must close and reopen the folder in Visual Studio to
activate the integration.

11. https://docs.microsoft.com/en-us/cpp/build/cmake-presets-vs?view=msvc-160#default-configure-presets
***(doesn't actually say which version..)
"Default Configure Presets
If no CMakePresets.json or CMakeUserPresets.json file exists, or if
CMakePresets.json or CMakeUserPresets.json is invalid, Visual Studio
will fall back*** on the following default Configure Presets:

Windows example
JSON
{
  "name": "windows-default",
  "displayName": "Windows x64 Debug",
  "description": "Sets Ninja generator, compilers, x64 architecture,
build and install directory, debug build type",
  "generator": "Ninja",
  "binaryDir": "${sourceDir}/out/build/${presetName}",
  "architecture": {
    "value": "x64",
    "strategy": "external"
  },
  "cacheVariables": {
    "CMAKE_BUILD_TYPE": "Debug",
    "CMAKE_INSTALL_PREFIX": "${sourceDir}/out/install/${presetName}"
  },
  "vendor": {
    "microsoft.com/VisualStudioSettings/CMake/1.0": {
      "hostOS": [ "Windows" ]
    }
  }
},
"

Signed-off-by: Philip Oakley <philipoakley@iee.email>
---
 contrib/buildsystems/CMakeLists.txt | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index d3d14501b437e2..03e63ec4feec7f 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -14,6 +14,11 @@ Note: Visual Studio also has the option of opening `CMakeLists.txt`
 directly; Using this option, Visual Studio will not find the source code,
 though, therefore the `File>Open>Folder...` option is preferred.
 
+Visual Studio does not produce a .sln solution file nor the .vcxproj files
+that may be required by VS extension tools.
+
+To generate the .sln/.vcxproj files run CMake manually, as described below.
+
 Instructions to run CMake manually:
 
     mkdir -p contrib/buildsystems/out
@@ -22,7 +27,7 @@ Instructions to run CMake manually:
 
 This will build the git binaries in contrib/buildsystems/out
 directory (our top-level .gitignore file knows to ignore contents of
-this directory).
+this directory). The project .sln and .vcxproj files are also generated.
 
 Possible build configurations(-DCMAKE_BUILD_TYPE) with corresponding
 compiler flags
@@ -35,17 +40,16 @@ empty(default) :
 NOTE: -DCMAKE_BUILD_TYPE is optional. For multi-config generators like Visual Studio
 this option is ignored
 
-This process generates a Makefile(Linux/*BSD/MacOS) , Visual Studio solution(Windows) by default.
+This process generates a Makefile(Linux/*BSD/MacOS), Visual Studio solution(Windows) by default.
 Run `make` to build Git on Linux/*BSD/MacOS.
 Open git.sln on Windows and build Git.
 
-NOTE: By default CMake uses Makefile as the build tool on Linux and Visual Studio in Windows,
-to use another tool say `ninja` add this to the command line when configuring.
-`-G Ninja`
-
 NOTE: By default CMake will install vcpkg locally to your source tree on configuration,
 to avoid this, add `-DNO_VCPKG=TRUE` to the command line when configuring.
 
+The Visual Studio default generator changed in v16.6 from its Visual Studio
+implemenation to `Ninja` This required changes to many CMake scripts.
+
 ]]
 cmake_minimum_required(VERSION 3.14)
 

From 5ba41773ec5b9cc5a125d6e136d29bd1b4a801dd Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.email>
Date: Sat, 24 Apr 2021 11:09:58 +0100
Subject: [PATCH 076/259] .gitignore: add Visual Studio CMakeSetting.json file

The CMakeSettings.json file is tool generated. Developers may track it
should they provide additional settings.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
---
 .gitignore | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.gitignore b/.gitignore
index 8caf3700c2305d..bf97276163b19b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -248,3 +248,4 @@ Release/
 /git.VC.db
 *.dSYM
 /contrib/buildsystems/out
+CMakeSettings.json

From 9282eff92c8a55f9cbbd78809adc3c2faa2cacfb Mon Sep 17 00:00:00 2001
From: Victoria Dye <vdye@github.com>
Date: Thu, 5 Aug 2021 19:04:13 -0400
Subject: [PATCH 077/259] subtree: update `contrib/subtree` `test` target

The intention of this change is to align with how the top-level git
`Makefile` defines its own test target (which also internally calls
`$(MAKE) -C t/ all`). This change also ensures the consistency of
`make -C contrib/subtree test` with other testing in CI executions
(which rely on `$DEFAULT_TEST_TARGET` being defined as `prove`).

Signed-off-by: Victoria Dye <vdye@github.com>
---
 contrib/subtree/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/contrib/subtree/Makefile b/contrib/subtree/Makefile
index 6fa7496bfdb3fd..6f6e90c4cb49b6 100644
--- a/contrib/subtree/Makefile
+++ b/contrib/subtree/Makefile
@@ -94,7 +94,7 @@ $(GIT_SUBTREE_TEST): $(GIT_SUBTREE)
 	cp $< $@
 
 test: $(GIT_SUBTREE_TEST)
-	$(MAKE) -C t/ test
+	$(MAKE) -C t/ all
 
 clean:
 	$(RM) $(GIT_SUBTREE)

From 8cfea371105acbf17a011ad0017e9bf7dfc4a660 Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.email>
Date: Thu, 22 Apr 2021 11:11:38 +0100
Subject: [PATCH 078/259] CMakeLists: add default "x64-windows" arch for Visual
 Studio

In Git-for-Windows, work on using ARM64 has progressed. The
commit 2d94b77b27 (cmake: allow building for Windows/ARM64, 2020-12-04)
failed to notice that /compat/vcbuild/vcpkg_install.bat will default to
using the "x64-windows" architecture for the vcpkg installation if not set,
but CMake is not told of this default. Commit 635b6d99b3 (vcbuild: install
ARM64 dependencies when building ARM64 binaries, 2020-01-31) later updated
vcpkg_install.bat to accept an arch (%1) parameter, but retained the default.

This default is neccessary for the use case where the project directory is
opened directly in Visual Studio, which will find and build a CMakeLists.txt
file without any parameters, thus expecting use of the default setting.

Also Visual studio will generate internal .sln solution and .vcxproj project
files needed for some extension tools. Inform users of the additional
.sln/.vcxproj generation.

** How to test:
 rm -rf '.vs' # remove old visual studio settings
 rm -rf 'compat/vcbuild/vcpkg' # remove any vcpkg downloads
 rm -rf 'contrib/buildsystems/out' # remove builds & CMake artifacts
 with a fresh Visual Studio Community Edition, File>>Open>>(git *folder*)
   to load the project (which will take some time!).
 check for successful compilation.
The implicit .sln (etc.) are in the hidden .vs directory created by
Visual Studio.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
---
 contrib/buildsystems/CMakeLists.txt | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index 03e63ec4feec7f..951473c76e046b 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -71,6 +71,10 @@ if(USE_VCPKG)
 		message("Initializing vcpkg and building the Git's dependencies (this will take a while...)")
 		execute_process(COMMAND ${CMAKE_SOURCE_DIR}/compat/vcbuild/vcpkg_install.bat ${VCPKG_ARCH})
 	endif()
+	if(NOT EXISTS ${VCPKG_ARCH})
+		message("VCPKG_ARCH: unset, using 'x64-windows'")
+		set(VCPKG_ARCH "x64-windows") # default from vcpkg_install.bat
+	endif()
 	list(APPEND CMAKE_PREFIX_PATH "${VCPKG_DIR}/installed/${VCPKG_ARCH}")
 
 	# In the vcpkg edition, we need this to be able to link to libcurl

From 7e4f22909930fad1dc62f980b1887dd998a8b75d Mon Sep 17 00:00:00 2001
From: Dennis Ameling <dennis@dennisameling.com>
Date: Mon, 19 Jul 2021 13:02:16 +0200
Subject: [PATCH 079/259] cmake(): allow setting HOST_CPU for cross-compilation

Git's regular Makefile mentions that HOST_CPU should be defined when cross-compiling Git: https://github.com/git-for-windows/git/blob/37796bca76ef4180c39ee508ca3e42c0777ba444/Makefile#L438-L439

This is then used to set the GIT_HOST_CPU variable when compiling Git: https://github.com/git-for-windows/git/blob/37796bca76ef4180c39ee508ca3e42c0777ba444/Makefile#L1337-L1341

Then, when the user runs `git version --build-options`, it returns that value: https://github.com/git-for-windows/git/blob/37796bca76ef4180c39ee508ca3e42c0777ba444/help.c#L658

This commit adds the same functionality to the CMake configuration. Users can now set -DHOST_CPU= to set the target architecture.

Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
---
 .github/workflows/main.yml          | 2 +-
 contrib/buildsystems/CMakeLists.txt | 9 ++++++++-
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index a3a97088cd8380..be34a81b4ec9ab 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -197,7 +197,7 @@ jobs:
       shell: bash
       run: |
         cmake `pwd`/contrib/buildsystems/ -DCMAKE_PREFIX_PATH=`pwd`/compat/vcbuild/vcpkg/installed/${{ matrix.arch }}-windows \
-        -DNO_GETTEXT=YesPlease -DPERL_TESTS=OFF -DPYTHON_TESTS=OFF -DCURL_NO_CURL_CMAKE=ON -DCMAKE_GENERATOR_PLATFORM=${{ matrix.arch }} -DVCPKG_ARCH=${{ matrix.arch }}-windows
+        -DNO_GETTEXT=YesPlease -DPERL_TESTS=OFF -DPYTHON_TESTS=OFF -DCURL_NO_CURL_CMAKE=ON -DCMAKE_GENERATOR_PLATFORM=${{ matrix.arch }} -DVCPKG_ARCH=${{ matrix.arch }}-windows -DHOST_CPU=${{ matrix.arch }}
     - name: MSBuild
       run: msbuild git.sln -property:Configuration=Release -property:Platform=${{ matrix.arch }} -maxCpuCount:4 -property:PlatformToolset=v142
     - name: bundle artifact tar
diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index fb1abbea219bde..d3d14501b437e2 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -223,7 +223,14 @@ endif()
 
 #default behaviour
 include_directories(${CMAKE_SOURCE_DIR})
-add_compile_definitions(GIT_HOST_CPU="${CMAKE_SYSTEM_PROCESSOR}")
+
+# When cross-compiling, define HOST_CPU as the canonical name of the CPU on
+# which the built Git will run (for instance "x86_64").
+if(NOT HOST_CPU)
+	add_compile_definitions(GIT_HOST_CPU="${CMAKE_SYSTEM_PROCESSOR}")
+else()
+	add_compile_definitions(GIT_HOST_CPU="${HOST_CPU}")
+endif()
 add_compile_definitions(SHA256_BLK INTERNAL_QSORT RUNTIME_PREFIX)
 add_compile_definitions(NO_OPENSSL SHA1_DC SHA1DC_NO_STANDARD_INCLUDES
 			SHA1DC_INIT_SAFE_HASH_DEFAULT=0

From b8b12967bde0c3c2ee784e0cd9581dab42ffb5f0 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 2 Apr 2021 22:50:54 +0200
Subject: [PATCH 080/259] mingw: allow for longer paths in
 `parse_interpreter()`
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

As reported in https://github.com/newren/git-filter-repo/pull/225, it
looks like 99 bytes is not really sufficient to represent e.g. the full
path to Python when installed via Windows Store (and this path is used
in the hasb bang line when installing scripts via `pip`).

Let's increase it to what is probably the maximum sensible path size:
MAX_PATH. This makes `parse_interpreter()` in line with what
`lookup_prog()` handles.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Vilius Šumskas <vilius@sumskas.eu>
---
 compat/mingw.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 29d3f09768c29a..afb6ccb95ef92a 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1269,7 +1269,7 @@ static const char *quote_arg_msys2(const char *arg)
 
 static const char *parse_interpreter(const char *cmd)
 {
-	static char buf[100];
+	static char buf[MAX_PATH];
 	char *p, *opt;
 	int n, fd;
 

From cab2b72d4b609e0f2a81cefc5f98b11e2dcdf523 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 17 May 2021 10:46:52 +0200
Subject: [PATCH 081/259] compat/vcbuild: document preferred way to build in
 Visual Studio

We used to have that `make vcxproj` hack, but a hack it is. In the
meantime, we have a much cleaner solution: using CMake, either
explicitly, or even more conveniently via Visual Studio's built-in CMake
support (simply open Git's top-level directory via File>Open>Folder...).

Let's let the `README` reflect this.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/vcbuild/README | 28 +++++++++-------------------
 1 file changed, 9 insertions(+), 19 deletions(-)

diff --git a/compat/vcbuild/README b/compat/vcbuild/README
index 29ec1d0f104b80..5c71ea2daa4017 100644
--- a/compat/vcbuild/README
+++ b/compat/vcbuild/README
@@ -37,27 +37,17 @@ The Steps to Build Git with VS2015 or VS2017 from the command line.
 
 ================================================================
 
-Alternatively, run `make vcxproj` and then load the generated `git.sln` in
-Visual Studio. The initial build will install the vcpkg system and build the
+Alternatively, just open Git's top-level directory in Visual Studio, via
+`File>Open>Folder...`. This will use CMake internally to generate the
+project definitions. It will also install the vcpkg system and build the
 dependencies automatically. This will take a while.
 
-Instead of generating the `git.sln` file yourself (which requires a full Git
-for Windows SDK), you may want to consider fetching the `vs/master` branch of
-https://github.com/git-for-windows/git instead (which is updated automatically
-via CI running `make vcxproj`). The `vs/master` branch does not require a Git
-for Windows to build, but you can run the test scripts in a regular Git Bash.
-
-Note that `make vcxproj` will automatically add and commit the generated `.sln`
-and `.vcxproj` files to the repo. This is necessary to allow building a
-fully-testable Git in Visual Studio, where a regular Git Bash can be used to
-run the test scripts (as opposed to a full Git for Windows SDK): a number of
-build targets, such as Git commands implemented as Unix shell scripts (where
-`@@SHELL_PATH@@` and other placeholders are interpolated) require a full-blown
-Git for Windows SDK (which is about 10x the size of a regular Git for Windows
-installation).
-
-If your plan is to open a Pull Request with Git for Windows, it is a good idea
-to drop this commit before submitting.
+You can also generate the Visual Studio solution manually by downloading
+and running CMake explicitly rather than letting Visual Studio doing
+that implicitly.
+
+Another, deprecated option is to run `make vcxproj`. This option is
+superseded by the CMake-based build, and will be removed at some point.
 
 ================================================================
 The Steps of Build Git with VS2008

From ed39322a64035ca9ff78fa2d9f992f77e7e5071d Mon Sep 17 00:00:00 2001
From: Pascal Muller <pascalmuller@gmail.com>
Date: Wed, 23 Jun 2021 21:21:10 +0200
Subject: [PATCH 082/259] http: optionally send SSL client certificate

This adds support for a new http.sslAutoClientCert config value.

In cURL 7.77 or later the schannel backend does not automatically send
client certificates from the Windows Certificate Store anymore.

This config value is only used if http.sslBackend is set to "schannel",
and can be used to opt in to the old behavior and force cURL to send
client certificates.

This fixes https://github.com/git-for-windows/git/issues/3292

Signed-off-by: Pascal Muller <pascalmuller@gmail.com>
---
 Documentation/config/http.txt |  5 +++++
 git-curl-compat.h             |  8 ++++++++
 http.c                        | 26 ++++++++++++++++++++++----
 3 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/Documentation/config/http.txt b/Documentation/config/http.txt
index 101487cfa43a32..dcd3dd90e34013 100644
--- a/Documentation/config/http.txt
+++ b/Documentation/config/http.txt
@@ -234,6 +234,11 @@ http.schannelUseSSLCAInfo::
 	when the `schannel` backend was configured via `http.sslBackend`,
 	unless `http.schannelUseSSLCAInfo` overrides this behavior.
 
+http.sslAutoClientCert::
+	As of cURL v7.77.0, the Secure Channel backend won't automatically
+	send client certificates from the Windows Certificate Store anymore.
+	To opt in to the old behavior, http.sslAutoClientCert can be set.
+
 http.pinnedPubkey::
 	Public key of the https service. It may either be the filename of
 	a PEM or DER encoded public key file or a string starting with
diff --git a/git-curl-compat.h b/git-curl-compat.h
index e1d0bdd273501f..d4755194ae0940 100644
--- a/git-curl-compat.h
+++ b/git-curl-compat.h
@@ -143,4 +143,12 @@
 #define GIT_CURL_HAVE_CURLOPT_PROTOCOLS_STR 1
 #endif
 
+/**
+ * CURLSSLOPT_AUTO_CLIENT_CERT was added in 7.77.0, released in May
+ * 2021.
+ */
+#if LIBCURL_VERSION_NUM >= 0x074d00
+#define GIT_CURL_HAVE_CURLSSLOPT_AUTO_CLIENT_CERT
+#endif
+
 #endif
diff --git a/http.c b/http.c
index f9c55c5cacff37..c89f96cebab17b 100644
--- a/http.c
+++ b/http.c
@@ -161,6 +161,8 @@ static int http_schannel_check_revoke_mode =
  */
 static int http_schannel_use_ssl_cainfo;
 
+static int http_auto_client_cert;
+
 static int always_auth_proactively(void)
 {
 	return http_proactive_auth != PROACTIVE_AUTH_NONE &&
@@ -449,6 +451,11 @@ static int http_options(const char *var, const char *value,
 		return 0;
 	}
 
+	if (!strcmp("http.sslautoclientcert", var)) {
+		http_auto_client_cert = git_config_bool(var, value);
+		return 0;
+	}
+
 	if (!strcmp("http.minsessions", var)) {
 		min_curl_sessions = git_config_int(var, value, ctx->kvi);
 		if (min_curl_sessions > 1)
@@ -1101,13 +1108,24 @@ static CURL *get_curl_handle(void)
 	}
 #endif
 
-	if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
-	    http_schannel_check_revoke_mode) {
+	if (http_ssl_backend && !strcmp("schannel", http_ssl_backend)) {
+		long ssl_options = 0;
+		if (http_schannel_check_revoke_mode) {
 #ifdef GIT_CURL_HAVE_CURLSSLOPT_NO_REVOKE
-		curl_easy_setopt(result, CURLOPT_SSL_OPTIONS, http_schannel_check_revoke_mode);
+			ssl_options |= http_schannel_check_revoke_mode;
 #else
-		warning(_("CURLSSLOPT_NO_REVOKE not supported with cURL < 7.44.0"));
+			warning(_("CURLSSLOPT_NO_REVOKE not supported with cURL < 7.44.0"));
 #endif
+		}
+
+		if (http_auto_client_cert) {
+#ifdef GIT_CURL_HAVE_CURLSSLOPT_AUTO_CLIENT_CERT
+			ssl_options |= CURLSSLOPT_AUTO_CLIENT_CERT;
+#endif
+		}
+
+		if (ssl_options)
+			curl_easy_setopt(result, CURLOPT_SSL_OPTIONS, ssl_options);
 	}
 
 	if (http_proactive_auth != PROACTIVE_AUTH_NONE)

From c7cf32d04d20e30ec68156eb9d8f7e8d62f1dfc8 Mon Sep 17 00:00:00 2001
From: Victoria Dye <vdye@github.com>
Date: Thu, 5 Aug 2021 19:11:59 -0400
Subject: [PATCH 083/259] ci: run `contrib/subtree` tests in CI builds

Because `git subtree` (unlike most other `contrib` modules) is included as
part of the standard release of Git for Windows, its stability should be
verified as consistently as it is for the rest of git. By including the
`git subtree` tests in the CI workflow, these tests are as much of a gate to
merging and indicator of stability as the standard test suite.

Signed-off-by: Victoria Dye <vdye@github.com>
---
 ci/run-build-and-tests.sh | 4 ++++
 ci/run-test-slice.sh      | 3 +++
 2 files changed, 7 insertions(+)

diff --git a/ci/run-build-and-tests.sh b/ci/run-build-and-tests.sh
index 98dda42045d3f3..18ffedba05081b 100755
--- a/ci/run-build-and-tests.sh
+++ b/ci/run-build-and-tests.sh
@@ -56,4 +56,8 @@ then
 fi
 check_unignored_build_artifacts
 
+case " $MAKE_TARGETS " in
+*" all "*) make -C contrib/subtree test;;
+esac
+
 save_good_tree
diff --git a/ci/run-test-slice.sh b/ci/run-test-slice.sh
index e167e646f79e3d..8cb0038d07ca64 100755
--- a/ci/run-test-slice.sh
+++ b/ci/run-test-slice.sh
@@ -20,4 +20,7 @@ if [ "$1" == "0" ] ; then
 	group "Run unit tests" make --quiet -C t unit-tests-test-tool
 fi
 
+# Run the git subtree tests only if main tests succeeded
+test 0 != "$1" || make -C contrib/subtree test
+
 check_unignored_build_artifacts

From 4ad003d5392d4999a16e148e9f0bd019091d01dd Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.email>
Date: Mon, 10 May 2021 16:47:40 +0100
Subject: [PATCH 084/259] CMake: show Win32 and Generator_platform build-option
 values

Ensure key CMake option values are part of the CMake output to
facilitate user support when tool updates impact the wider CMake
actions, particularly ongoing 'improvements' in Visual Studio.

These CMake displays perform the same function as the build-options.txt
provided in the main Git for Windows. CMake is already chatty.
The setting of CMAKE_EXPORT_COMPILE_COMMANDS is also reported.

Include the environment's CMAKE_EXPORT_COMPILE_COMMANDS value which
may have been propogated to CMake's internal value.

Testing the CMAKE_EXPORT_COMPILE_COMMANDS processing can be difficult
in the Visual Studio environment, as it may be cached in many places.
The 'environment' may include the OS, the user shell, CMake's
own environment, along with the Visual Studio presets and caches.

See previous commit for arefacts that need removing for a clean test.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
---
 contrib/buildsystems/CMakeLists.txt | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index 951473c76e046b..5100383ede92e0 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -63,10 +63,20 @@ endif()
 
 if(NOT DEFINED CMAKE_EXPORT_COMPILE_COMMANDS)
 	set(CMAKE_EXPORT_COMPILE_COMMANDS TRUE)
+	message("settting CMAKE_EXPORT_COMPILE_COMMANDS: ${CMAKE_EXPORT_COMPILE_COMMANDS}")
 endif()
 
 if(USE_VCPKG)
 	set(VCPKG_DIR "${CMAKE_SOURCE_DIR}/compat/vcbuild/vcpkg")
+	message("WIN32: ${WIN32}") # show its underlying text values
+	message("VCPKG_DIR: ${VCPKG_DIR}")
+	message("VCPKG_ARCH: ${VCPKG_ARCH}") # maybe unset
+	message("MSVC: ${MSVC}")
+	message("CMAKE_GENERATOR: ${CMAKE_GENERATOR}")
+	message("CMAKE_CXX_COMPILER_ID: ${CMAKE_CXX_COMPILER_ID}")
+	message("CMAKE_GENERATOR_PLATFORM: ${CMAKE_GENERATOR_PLATFORM}")
+	message("CMAKE_EXPORT_COMPILE_COMMANDS: ${CMAKE_EXPORT_COMPILE_COMMANDS}")
+	message("ENV(CMAKE_EXPORT_COMPILE_COMMANDS): $ENV{CMAKE_EXPORT_COMPILE_COMMANDS}")
 	if(NOT EXISTS ${VCPKG_DIR})
 		message("Initializing vcpkg and building the Git's dependencies (this will take a while...)")
 		execute_process(COMMAND ${CMAKE_SOURCE_DIR}/compat/vcbuild/vcpkg_install.bat ${VCPKG_ARCH})

From 404d93bfb437780bb84715929ec9a9dffa1c02bf Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 8 Sep 2021 13:05:42 +0200
Subject: [PATCH 085/259] init: do parse _all_ core.* settings early

In Git for Windows, `has_symlinks` is set to 0 by default. Therefore, we
need to parse the config setting `core.symlinks` to know if it has been
set to `true`. In `git init`, we must do that before copying the
templates because they might contain symbolic links.

Even if the support for symbolic links on Windows has not made it to
upstream Git yet, we really should make sure that all the `core.*`
settings are parsed before proceeding, as they might very well change
the behavior of `git init` in a way the user intended.

This fixes https://github.com/git-for-windows/git/issues/3414

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 config.c | 4 ++--
 config.h | 2 ++
 setup.c  | 2 +-
 3 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/config.c b/config.c
index 05f369ec0d8876..0a8d6901c83608 100644
--- a/config.c
+++ b/config.c
@@ -1387,8 +1387,8 @@ int git_config_color(char *dest, const char *var, const char *value)
 	return 0;
 }
 
-static int git_default_core_config(const char *var, const char *value,
-				   const struct config_context *ctx, void *cb)
+int git_default_core_config(const char *var, const char *value,
+			    const struct config_context *ctx, void *cb)
 {
 	/* This needs a better name */
 	if (!strcmp(var, "core.filemode")) {
diff --git a/config.h b/config.h
index 54b47dec9e2709..418384646b04d3 100644
--- a/config.h
+++ b/config.h
@@ -167,6 +167,8 @@ typedef int (*config_fn_t)(const char *, const char *,
 
 int git_default_config(const char *, const char *,
 		       const struct config_context *, void *);
+int git_default_core_config(const char *var, const char *value,
+			    const struct config_context *ctx, void *cb);
 
 /**
  * Read a specific file in git-config format.
diff --git a/setup.c b/setup.c
index 5f81d9fac0d7e8..79c8f52e59bd83 100644
--- a/setup.c
+++ b/setup.c
@@ -2411,7 +2411,7 @@ int init_db(const char *git_dir, const char *real_git_dir,
 	 * have set up the repository format such that we can evaluate
 	 * includeIf conditions correctly in the case of re-initialization.
 	 */
-	git_config(platform_core_config, NULL);
+	git_config(git_default_core_config, NULL);
 
 	safe_create_dir(git_dir, 0);
 

From f02954cd3b4a36874c27a482c8221270a0bfcbb1 Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.email>
Date: Sun, 31 Oct 2021 23:15:13 +0000
Subject: [PATCH 086/259] hash-object: demonstrate a >4GB/LLP64 problem

On LLP64 systems, such as Windows, the size of `long`, `int`, etc. is
only 32 bits (for backward compatibility). Git's use of `unsigned long`
for file memory sizes in many places, rather than size_t, limits the
handling of large files on LLP64 systems (commonly given as `>4GB`).

Provide a minimum test for handling a >4GB file. The `hash-object`
command, with the  `--literally` and without `-w` option avoids
writing the object, either loose or packed. This avoids the code paths
hitting the `bigFileThreshold` config test code, the zlib code, and the
pack code.

Subsequent patches will walk the test's call chain, converting types to
`size_t` (which is larger in LLP64 data models) where appropriate.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t1007-hash-object.sh | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/t/t1007-hash-object.sh b/t/t1007-hash-object.sh
index d73a5cc23705e2..6299612850e574 100755
--- a/t/t1007-hash-object.sh
+++ b/t/t1007-hash-object.sh
@@ -50,6 +50,9 @@ test_expect_success 'setup' '
 
 	example sha1:ddd3f836d3e3fbb7ae289aa9ae83536f76956399
 	example sha256:b44fe1fe65589848253737db859bd490453510719d7424daab03daf0767b85ae
+
+	large5GB sha1:0be2be10a4c8764f32c4bf372a98edc731a4b204
+	large5GB sha256:dc18ca621300c8d3cfa505a275641ebab00de189859e022a975056882d313e64
 	EOF
 '
 
@@ -266,4 +269,12 @@ test_expect_success '--stdin outside of repository (uses SHA-1)' '
 	test_cmp expect actual
 '
 
+test_expect_failure EXPENSIVE,SIZE_T_IS_64BIT,!LONG_IS_64BIT \
+		'files over 4GB hash literally' '
+	test-tool genzeros $((5*1024*1024*1024)) >big &&
+	test_oid large5GB >expect &&
+	git hash-object --stdin --literally <big >actual &&
+	test_cmp expect actual
+'
+
 test_done

From 7eff60f85d30d3c98715667dee350438905a03f7 Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.email>
Date: Fri, 12 Nov 2021 21:07:03 +0000
Subject: [PATCH 087/259] write_object_file_literally(): use size_t

The previous commit adds a test that demonstrates a problem in the
`hash-object --literally` command, manifesting in an unnecessary file
size limit on systems using the LLP64 data model (which includes
Windows).

Walking the affected code path is `cmd_hash_object()` >> `hash_fd()` >>
`hash_literally()` >> `hash_object_file_literally()`.

The function `hash_object_file_literally()` is the first with a file
length parameter (via a mem buffer). This commit changes the type of
that parameter to the LLP64 compatible `size_t` type.

There are no other uses of the function. The `strbuf` type is already
`size_t` compatible.

Note: The hash-object test does not yet pass. Subsequent commits will
continue to walk the call tree's lower level functions to identify
further fixes.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 object-file.c     | 4 ++--
 object-store-ll.h | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/object-file.c b/object-file.c
index 065103be3ea923..737a4902d5f183 100644
--- a/object-file.c
+++ b/object-file.c
@@ -1889,7 +1889,7 @@ static void write_object_file_prepare(const struct git_hash_algo *algo,
 }
 
 static void write_object_file_prepare_literally(const struct git_hash_algo *algo,
-				      const void *buf, unsigned long len,
+				      const void *buf, size_t len,
 				      const char *type, struct object_id *oid,
 				      char *hdr, int *hdrlen)
 {
@@ -2357,7 +2357,7 @@ int write_object_file_flags(const void *buf, unsigned long len,
 	return 0;
 }
 
-int write_object_file_literally(const void *buf, unsigned long len,
+int write_object_file_literally(const void *buf, size_t len,
 				const char *type, struct object_id *oid,
 				unsigned flags)
 {
diff --git a/object-store-ll.h b/object-store-ll.h
index c5f2bb2fc2fe6e..e1d61d15ffccda 100644
--- a/object-store-ll.h
+++ b/object-store-ll.h
@@ -262,7 +262,7 @@ static inline int write_object_file(const void *buf, unsigned long len,
 	return write_object_file_flags(buf, len, type, oid, NULL, 0);
 }
 
-int write_object_file_literally(const void *buf, unsigned long len,
+int write_object_file_literally(const void *buf, size_t len,
 				const char *type, struct object_id *oid,
 				unsigned flags);
 int stream_loose_object(struct input_stream *in_stream, size_t len,

From eb7bc6b6543af872b4b73ee44afab392b71a2509 Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.email>
Date: Fri, 12 Nov 2021 21:14:50 +0000
Subject: [PATCH 088/259] object-file.c: use size_t for header lengths

Continue walking the code path for the >4GB `hash-object --literally`
test. The `hash_object_file_literally()` function internally uses both
`hash_object_file()` and `write_object_file_prepare()`. Both function
signatures use `unsigned long` rather than `size_t` for the mem buffer
sizes. Use `size_t` instead, for LLP64 compatibility.

While at it, convert those function's object's header buffer length to
`size_t` for consistency. The value is already upcast to `uintmax_t` for
print format compatibility.

Note: The hash-object test still does not pass. A subsequent commit
continues to walk the call tree's lower level hash functions to identify
further fixes.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 object-file.c     | 22 +++++++++++-----------
 object-store-ll.h |  4 ++--
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/object-file.c b/object-file.c
index 737a4902d5f183..4b0f0d4a6749bf 100644
--- a/object-file.c
+++ b/object-file.c
@@ -1866,7 +1866,7 @@ void *read_object_with_reference(struct repository *r,
 static void hash_object_body(const struct git_hash_algo *algo, git_hash_ctx *c,
 			     const void *buf, unsigned long len,
 			     struct object_id *oid,
-			     char *hdr, int *hdrlen)
+			     char *hdr, size_t *hdrlen)
 {
 	algo->init_fn(c);
 	algo->update_fn(c, hdr, *hdrlen);
@@ -1875,9 +1875,9 @@ static void hash_object_body(const struct git_hash_algo *algo, git_hash_ctx *c,
 }
 
 static void write_object_file_prepare(const struct git_hash_algo *algo,
-				      const void *buf, unsigned long len,
+				      const void *buf, size_t len,
 				      enum object_type type, struct object_id *oid,
-				      char *hdr, int *hdrlen)
+				      char *hdr, size_t *hdrlen)
 {
 	git_hash_ctx c;
 
@@ -1891,7 +1891,7 @@ static void write_object_file_prepare(const struct git_hash_algo *algo,
 static void write_object_file_prepare_literally(const struct git_hash_algo *algo,
 				      const void *buf, size_t len,
 				      const char *type, struct object_id *oid,
-				      char *hdr, int *hdrlen)
+				      char *hdr, size_t *hdrlen)
 {
 	git_hash_ctx c;
 
@@ -1943,17 +1943,17 @@ int finalize_object_file(const char *tmpfile, const char *filename)
 }
 
 static void hash_object_file_literally(const struct git_hash_algo *algo,
-				       const void *buf, unsigned long len,
+				       const void *buf, size_t len,
 				       const char *type, struct object_id *oid)
 {
 	char hdr[MAX_HEADER_LEN];
-	int hdrlen = sizeof(hdr);
+	size_t hdrlen = sizeof(hdr);
 
 	write_object_file_prepare_literally(algo, buf, len, type, oid, hdr, &hdrlen);
 }
 
 void hash_object_file(const struct git_hash_algo *algo, const void *buf,
-		      unsigned long len, enum object_type type,
+		      size_t len, enum object_type type,
 		      struct object_id *oid)
 {
 	hash_object_file_literally(algo, buf, len, type_name(type), oid);
@@ -2317,7 +2317,7 @@ int stream_loose_object(struct input_stream *in_stream, size_t len,
 	return err;
 }
 
-int write_object_file_flags(const void *buf, unsigned long len,
+int write_object_file_flags(const void *buf, size_t len,
 			    enum object_type type, struct object_id *oid,
 			    struct object_id *compat_oid_in, unsigned flags)
 {
@@ -2326,7 +2326,7 @@ int write_object_file_flags(const void *buf, unsigned long len,
 	const struct git_hash_algo *compat = repo->compat_hash_algo;
 	struct object_id compat_oid;
 	char hdr[MAX_HEADER_LEN];
-	int hdrlen = sizeof(hdr);
+	size_t hdrlen = sizeof(hdr);
 
 	/* Generate compat_oid */
 	if (compat) {
@@ -2366,8 +2366,8 @@ int write_object_file_literally(const void *buf, size_t len,
 	const struct git_hash_algo *algo = repo->hash_algo;
 	const struct git_hash_algo *compat = repo->compat_hash_algo;
 	struct object_id compat_oid;
-	int hdrlen, status = 0;
-	int compat_type = -1;
+	size_t hdrlen;
+	int status = 0, compat_type = -1;
 
 	if (compat) {
 		compat_type = type_from_string_gently(type, -1, 1);
diff --git a/object-store-ll.h b/object-store-ll.h
index e1d61d15ffccda..ccade7117f8e37 100644
--- a/object-store-ll.h
+++ b/object-store-ll.h
@@ -250,10 +250,10 @@ void *repo_read_object_file(struct repository *r,
 int oid_object_info(struct repository *r, const struct object_id *, unsigned long *);
 
 void hash_object_file(const struct git_hash_algo *algo, const void *buf,
-		      unsigned long len, enum object_type type,
+		      size_t len, enum object_type type,
 		      struct object_id *oid);
 
-int write_object_file_flags(const void *buf, unsigned long len,
+int write_object_file_flags(const void *buf, size_t len,
 			    enum object_type type, struct object_id *oid,
 			    struct object_id *comapt_oid_in, unsigned flags);
 static inline int write_object_file(const void *buf, unsigned long len,

From 6faae20dc89d42e874bf2b69a0584a19344784f1 Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.email>
Date: Fri, 12 Nov 2021 21:16:51 +0000
Subject: [PATCH 089/259] hash algorithms: use size_t for section lengths

Continue walking the code path for the >4GB `hash-object --literally`
test to the hash algorithm step for LLP64 systems.

This patch lets the SHA1DC code use `size_t`, making it compatible with
LLP64 data models (as used e.g. by Windows).

The interested reader of this patch will note that we adjust the
signature of the `git_SHA1DCUpdate()` function without updating _any_
call site. This certainly puzzled at least one reviewer already, so here
is an explanation:

This function is never called directly, but always via the macro
`platform_SHA1_Update`, which is usually called via the macro
`git_SHA1_Update`. However, we never call `git_SHA1_Update()` directly
in `struct git_hash_algo`. Instead, we call `git_hash_sha1_update()`,
which is defined thusly:

    static void git_hash_sha1_update(git_hash_ctx *ctx,
                                     const void *data, size_t len)
    {
        git_SHA1_Update(&ctx->sha1, data, len);
    }

i.e. it contains an implicit downcast from `size_t` to `unsigned long`
(before this here patch). With this patch, there is no downcast anymore.

With this patch, finally, the t1007-hash-object.sh "files over 4GB hash
literally" test case is fixed.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 object-file.c          | 4 ++--
 sha1dc_git.c           | 3 +--
 sha1dc_git.h           | 2 +-
 t/t1007-hash-object.sh | 2 +-
 4 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/object-file.c b/object-file.c
index 4b0f0d4a6749bf..c672adc74ca791 100644
--- a/object-file.c
+++ b/object-file.c
@@ -1864,7 +1864,7 @@ void *read_object_with_reference(struct repository *r,
 }
 
 static void hash_object_body(const struct git_hash_algo *algo, git_hash_ctx *c,
-			     const void *buf, unsigned long len,
+			     const void *buf, size_t len,
 			     struct object_id *oid,
 			     char *hdr, size_t *hdrlen)
 {
@@ -1884,7 +1884,7 @@ static void write_object_file_prepare(const struct git_hash_algo *algo,
 	/* Generate the header */
 	*hdrlen = format_object_header(hdr, *hdrlen, type, len);
 
-	/* Sha1.. */
+	/* Hash (function pointers) computation */
 	hash_object_body(algo, &c, buf, len, oid, hdr, hdrlen);
 }
 
diff --git a/sha1dc_git.c b/sha1dc_git.c
index 9b675a046ee699..fe58d7962a30c9 100644
--- a/sha1dc_git.c
+++ b/sha1dc_git.c
@@ -27,10 +27,9 @@ void git_SHA1DCFinal(unsigned char hash[20], SHA1_CTX *ctx)
 /*
  * Same as SHA1DCUpdate, but adjust types to match git's usual interface.
  */
-void git_SHA1DCUpdate(SHA1_CTX *ctx, const void *vdata, unsigned long len)
+void git_SHA1DCUpdate(SHA1_CTX *ctx, const void *vdata, size_t len)
 {
 	const char *data = vdata;
-	/* We expect an unsigned long, but sha1dc only takes an int */
 	while (len > INT_MAX) {
 		SHA1DCUpdate(ctx, data, INT_MAX);
 		data += INT_MAX;
diff --git a/sha1dc_git.h b/sha1dc_git.h
index 60e3ce84395cea..159540e13a382a 100644
--- a/sha1dc_git.h
+++ b/sha1dc_git.h
@@ -15,7 +15,7 @@ void git_SHA1DCInit(SHA1_CTX *);
 #endif
 
 void git_SHA1DCFinal(unsigned char [20], SHA1_CTX *);
-void git_SHA1DCUpdate(SHA1_CTX *ctx, const void *data, unsigned long len);
+void git_SHA1DCUpdate(SHA1_CTX *ctx, const void *data, size_t len);
 
 #define platform_SHA_IS_SHA1DC /* used by "test-tool sha1-is-sha1dc" */
 #define platform_SHA_CTX SHA1_CTX
diff --git a/t/t1007-hash-object.sh b/t/t1007-hash-object.sh
index 6299612850e574..62166f5c057779 100755
--- a/t/t1007-hash-object.sh
+++ b/t/t1007-hash-object.sh
@@ -269,7 +269,7 @@ test_expect_success '--stdin outside of repository (uses SHA-1)' '
 	test_cmp expect actual
 '
 
-test_expect_failure EXPENSIVE,SIZE_T_IS_64BIT,!LONG_IS_64BIT \
+test_expect_success EXPENSIVE,SIZE_T_IS_64BIT,!LONG_IS_64BIT \
 		'files over 4GB hash literally' '
 	test-tool genzeros $((5*1024*1024*1024)) >big &&
 	test_oid large5GB >expect &&

From fc3e62eceb086afc79c6db636ea96675bfb0ab32 Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.email>
Date: Mon, 6 Dec 2021 22:26:50 +0000
Subject: [PATCH 090/259] hash-object --stdin: verify that it works with
 >4GB/LLP64

Just like the `hash-object --literally` code path, the `--stdin` code
path also needs to use `size_t` instead of `unsigned long` to represent
memory sizes, otherwise it would cause problems on platforms using the
LLP64 data model (such as Windows).

To limit the scope of the test case, the object is explicitly not
written to the object store, nor are any filters applied.

The `big` file from the previous test case is reused to save setup time;
To avoid relying on that side effect, it is generated if it does not
exist (e.g. when running via `sh t1007-*.sh --long --run=1,41`).

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t1007-hash-object.sh | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/t/t1007-hash-object.sh b/t/t1007-hash-object.sh
index 62166f5c057779..03cd0f8ba83532 100755
--- a/t/t1007-hash-object.sh
+++ b/t/t1007-hash-object.sh
@@ -277,4 +277,12 @@ test_expect_success EXPENSIVE,SIZE_T_IS_64BIT,!LONG_IS_64BIT \
 	test_cmp expect actual
 '
 
+test_expect_success EXPENSIVE,SIZE_T_IS_64BIT,!LONG_IS_64BIT \
+		'files over 4GB hash correctly via --stdin' '
+	{ test -f big || test-tool genzeros $((5*1024*1024*1024)) >big; } &&
+	test_oid large5GB >expect &&
+	git hash-object --stdin <big >actual &&
+	test_cmp expect actual
+'
+
 test_done

From 0f5221e9b0e9d1fe9fa434fb7a71cbfe8893a410 Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.email>
Date: Mon, 6 Dec 2021 22:42:46 +0000
Subject: [PATCH 091/259] hash-object: add another >4GB/LLP64 test case

To complement the `--stdin` and `--literally` test cases that verify
that we can hash files larger than 4GB on 64-bit platforms using the
LLP64 data model, here is a test case that exercises `hash-object`
_without_ any options.

Just as before, we use the `big` file from the previous test case if it
exists to save on setup time, otherwise generate it.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t1007-hash-object.sh | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/t/t1007-hash-object.sh b/t/t1007-hash-object.sh
index 03cd0f8ba83532..3ece6a9349ac53 100755
--- a/t/t1007-hash-object.sh
+++ b/t/t1007-hash-object.sh
@@ -285,4 +285,12 @@ test_expect_success EXPENSIVE,SIZE_T_IS_64BIT,!LONG_IS_64BIT \
 	test_cmp expect actual
 '
 
+test_expect_success EXPENSIVE,SIZE_T_IS_64BIT,!LONG_IS_64BIT \
+		'files over 4GB hash correctly' '
+	{ test -f big || test-tool genzeros $((5*1024*1024*1024)) >big; } &&
+	test_oid large5GB >expect &&
+	git hash-object -- big >actual &&
+	test_cmp expect actual
+'
+
 test_done

From 1023670e95fb0c6eb49392d631533c4982c791fa Mon Sep 17 00:00:00 2001
From: Derrick Stolee <derrickstolee@github.com>
Date: Wed, 13 Apr 2022 14:49:17 -0400
Subject: [PATCH 092/259] setup: properly use "%(prefix)/" when in WSL

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
---
 setup.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/setup.c b/setup.c
index 5f81d9fac0d7e8..a6abc27334834f 100644
--- a/setup.c
+++ b/setup.c
@@ -1671,10 +1671,19 @@ const char *setup_git_directory_gently(int *nongit_ok)
 		break;
 	case GIT_DIR_INVALID_OWNERSHIP:
 		if (!nongit_ok) {
+			struct strbuf prequoted = STRBUF_INIT;
 			struct strbuf quoted = STRBUF_INIT;
 
 			strbuf_complete(&report, '\n');
-			sq_quote_buf_pretty(&quoted, dir.buf);
+
+#ifdef __MINGW32__
+			if (dir.buf[0] == '/')
+				strbuf_addstr(&prequoted, "%(prefix)/");
+#endif
+
+			strbuf_add(&prequoted, dir.buf, dir.len);
+			sq_quote_buf_pretty(&quoted, prequoted.buf);
+
 			die(_("detected dubious ownership in repository at '%s'\n"
 			      "%s"
 			      "To add an exception for this directory, call:\n"

From a77fce499c42e60a74949ea35dc3805245f121f8 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 5 Mar 2021 23:12:11 +0100
Subject: [PATCH 093/259] Enable the built-in FSMonitor as an experimental
 feature

If `feature.experimental` and `feature.manyFiles` are set and the user
has not explicitly turned off the builtin FSMonitor, we now start
the built-in FSMonitor by default.

Only forcing it when UNSET matches the behavior of UPDATE_DEFAULT_BOOL()
used for other repo settings.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 repo-settings.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/repo-settings.c b/repo-settings.c
index 2b4e68731bedce..f104e6fc73c38f 100644
--- a/repo-settings.c
+++ b/repo-settings.c
@@ -2,6 +2,8 @@
 #include "config.h"
 #include "repository.h"
 #include "midx.h"
+#include "fsmonitor-ipc.h"
+#include "fsmonitor-settings.h"
 
 static void repo_cfg_bool(struct repository *r, const char *key, int *dest,
 			  int def)
@@ -45,6 +47,30 @@ void prepare_repo_settings(struct repository *r)
 		r->settings.fetch_negotiation_algorithm = FETCH_NEGOTIATION_SKIPPING;
 		r->settings.pack_use_bitmap_boundary_traversal = 1;
 		r->settings.pack_use_multi_pack_reuse = 1;
+
+		/*
+		 * Force enable the builtin FSMonitor (unless the repo
+		 * is incompatible or they've already selected it or
+		 * the hook version).  But only if they haven't
+		 * explicitly turned it off -- so only if our config
+		 * value is UNSET.
+		 *
+		 * lookup_fsmonitor_settings() and check_for_ipc() do
+		 * not distinguish between explicitly set FALSE and
+		 * UNSET, so we re-test for an UNSET config key here.
+		 *
+		 * I'm not sure I want to fix fsmonitor-settings.c to
+		 * have more than one _DISABLED state since our usage
+		 * here is only to support this experimental period
+		 * (and I don't want to overload the _reason field
+		 * because it describes incompabilities).
+		 */
+		if (manyfiles &&
+		    fsmonitor_ipc__is_supported()  &&
+		    fsm_settings__get_mode(r) == FSMONITOR_MODE_DISABLED &&
+		    repo_config_get_maybe_bool(r, "core.fsmonitor", &value) > 0 &&
+		    repo_config_get_bool(r, "core.useBuiltinFSMonitor", &value))
+			fsm_settings__set_ipc(r);
 	}
 	if (manyfiles) {
 		r->settings.index_version = 4;

From c4fe288ac6aabc82ac4dec438d399b01ab3e977e Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.email>
Date: Tue, 7 Dec 2021 09:53:41 +0000
Subject: [PATCH 094/259] hash-object: add a >4GB/LLP64 test case using
 filtered input

To verify that the `clean` side of the `clean`/`smudge` filter code is
correct with regards to LLP64 (read: to ensure that `size_t` is used
instead of `unsigned long`), here is a test case using a trivial filter,
specifically _not_ writing anything to the object store to limit the
scope of the test case.

As in previous commits, the `big` file from previous test cases is
reused if available, to save setup time, otherwise re-generated.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t1007-hash-object.sh | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/t/t1007-hash-object.sh b/t/t1007-hash-object.sh
index 3ece6a9349ac53..3035e612c0f42b 100755
--- a/t/t1007-hash-object.sh
+++ b/t/t1007-hash-object.sh
@@ -293,4 +293,16 @@ test_expect_success EXPENSIVE,SIZE_T_IS_64BIT,!LONG_IS_64BIT \
 	test_cmp expect actual
 '
 
+# This clean filter does nothing, other than excercising the interface.
+# We ensure that cleaning doesn't mangle large files on 64-bit Windows.
+test_expect_success EXPENSIVE,SIZE_T_IS_64BIT,!LONG_IS_64BIT \
+		'hash filtered files over 4GB correctly' '
+	{ test -f big || test-tool genzeros $((5*1024*1024*1024)) >big; } &&
+	test_oid large5GB >expect &&
+	test_config filter.null-filter.clean "cat" &&
+	echo "big filter=null-filter" >.gitattributes &&
+	git hash-object -- big >actual &&
+	test_cmp expect actual
+'
+
 test_done

From f86fa9fcc4477605aaa165a847b62148c089eadc Mon Sep 17 00:00:00 2001
From: Derrick Stolee <derrickstolee@github.com>
Date: Wed, 13 Apr 2022 14:54:43 -0400
Subject: [PATCH 095/259] compat/mingw.c: do not warn when failing to get owner

In the case of Git for Windows (say, in a Git Bash window) running in a
Windows Subsystem for Linux (WSL) directory, the GetNamedSecurityInfoW()
call in is_path_owned_By_current_side() returns an error code other than
ERROR_SUCCESS. This is consistent behavior across this boundary.

In these cases, the owner would always be different because the WSL
owner is a different entity than the Windows user.

The change here is to suppress the error message that looks like this:

  error: failed to get owner for '//wsl.localhost/...' (1)

Before this change, this warning happens for every Git command,
regardless of whether the directory is marked with safe.directory.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
---
 compat/mingw.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 29d3f09768c29a..6c2bb00cfacfe7 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2771,9 +2771,7 @@ int is_path_owned_by_current_sid(const char *path, struct strbuf *report)
 				    DACL_SECURITY_INFORMATION,
 				    &sid, NULL, NULL, NULL, &descriptor);
 
-	if (err != ERROR_SUCCESS)
-		error(_("failed to get owner for '%s' (%ld)"), path, err);
-	else if (sid && IsValidSid(sid)) {
+	if (err == ERROR_SUCCESS && sid && IsValidSid(sid)) {
 		/* Now, verify that the SID matches the current user's */
 		static PSID current_user_sid;
 		BOOL is_member;

From f5db3d8c27ba1d0505fe29247b82b9fc1e53c60d Mon Sep 17 00:00:00 2001
From: Rafael Kitover <rkitover@gmail.com>
Date: Tue, 12 Apr 2022 19:53:33 +0000
Subject: [PATCH 096/259] mingw: $env:TERM="xterm-256color" for newer OSes

For Windows builds >= 15063 set $env:TERM to "xterm-256color" instead of
"cygwin" because they have a more capable console system that supports
this. Also set $env:COLORTERM="truecolor" if unset.

$env:TERM is initialized so that ANSI colors in color.c work, see
29a3963484 (Win32: patch Windows environment on startup, 2012-01-15).

See git-for-windows/git#3629 regarding problems caused by always setting
$env:TERM="cygwin".

This is the same heuristic used by the Cygwin runtime.

Signed-off-by: Rafael Kitover <rkitover@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 29d3f09768c29a..0824849f209e4a 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2642,9 +2642,20 @@ static void setup_windows_environment(void)
 		convert_slashes(tmp);
 	}
 
-	/* simulate TERM to enable auto-color (see color.c) */
-	if (!getenv("TERM"))
-		setenv("TERM", "cygwin", 1);
+
+	/*
+	 * Make sure TERM is set up correctly to enable auto-color
+	 * (see color.c .) Use "cygwin" for older OS releases which
+	 * works correctly with MSYS2 utilities on older consoles.
+	 */
+	if (!getenv("TERM")) {
+		if ((GetVersion() >> 16) < 15063)
+			setenv("TERM", "cygwin", 0);
+		else {
+			setenv("TERM", "xterm-256color", 0);
+			setenv("COLORTERM", "truecolor", 0);
+		}
+	}
 
 	/* calculate HOME if not set */
 	if (!getenv("HOME")) {

From cb96a6eb05566c75e4946e46489b26b1f052acc2 Mon Sep 17 00:00:00 2001
From: Christopher Degawa <ccom@randomderp.com>
Date: Sat, 28 May 2022 14:53:54 -0500
Subject: [PATCH 097/259] winansi: check result and Buffer before using Name

NtQueryObject under Wine can return a success but fill out no name.
In those situations, Wine will set Buffer to NULL, and set result to
the sizeof(OBJECT_NAME_INFORMATION).

Running a command such as

echo "$(git.exe --version 2>/dev/null)"

will crash due to a NULL pointer dereference when the code attempts to
null terminate the buffer, although, weirdly, removing the subshell or
redirecting stdout to a file will not trigger the crash.

Code has been added to also check Buffer and Length to ensure the check
is as robust as possible due to the current behavior being fragile at
best, and could potentially change in the future

This code is based on the behavior of NtQueryObject under wine and
reactos.

Signed-off-by: Christopher Degawa <ccom@randomderp.com>
---
 compat/winansi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/compat/winansi.c b/compat/winansi.c
index 575813bde8e806..993c9a7945f8a6 100644
--- a/compat/winansi.c
+++ b/compat/winansi.c
@@ -573,6 +573,9 @@ static void detect_msys_tty(int fd)
 	if (!NT_SUCCESS(NtQueryObject(h, ObjectNameInformation,
 			buffer, sizeof(buffer) - 2, &result)))
 		return;
+	if (result < sizeof(*nameinfo) || !nameinfo->Name.Buffer ||
+		!nameinfo->Name.Length)
+		return;
 	name = nameinfo->Name.Buffer;
 	name[nameinfo->Name.Length / sizeof(*name)] = 0;
 

From 14c432a7da15f6be13e052bd958f143aa645d100 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=AD=99=E5=8D=93=E8=AF=86?= <sunzhuoshi@gmail.com>
Date: Sun, 16 Jan 2022 03:38:33 +0800
Subject: [PATCH 098/259] Add config option `windows.appendAtomically`
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Atomic append on windows is only supported on local disk files, and it may
cause errors in other situations, e.g. network file system. If that is the
case, this config option should be used to turn atomic append off.

Co-Authored-By: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: 孙卓识 <sunzhuoshi@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 Documentation/config.txt         |  2 ++
 Documentation/config/windows.txt |  4 ++++
 compat/mingw.c                   | 37 +++++++++++++++++++++++++++++---
 3 files changed, 40 insertions(+), 3 deletions(-)
 create mode 100644 Documentation/config/windows.txt

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 8c0b3ed8075214..f1510a85205487 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -554,4 +554,6 @@ include::config/versionsort.txt[]
 
 include::config/web.txt[]
 
+include::config/windows.txt[]
+
 include::config/worktree.txt[]
diff --git a/Documentation/config/windows.txt b/Documentation/config/windows.txt
new file mode 100644
index 00000000000000..fdaaf1c65504f3
--- /dev/null
+++ b/Documentation/config/windows.txt
@@ -0,0 +1,4 @@
+windows.appendAtomically::
+	By default, append atomic API is used on windows. But it works only with
+	local disk files, if you're working on a network file system, you should
+	set it false to turn it off.
diff --git a/compat/mingw.c b/compat/mingw.c
index 29d3f09768c29a..d9477f9e5a4e64 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1,3 +1,4 @@
+#define USE_THE_REPOSITORY_VARIABLE
 #include "../git-compat-util.h"
 #include "win32.h"
 #include <aclapi.h>
@@ -18,6 +19,7 @@
 #include "gettext.h"
 #define SECURITY_WIN32
 #include <sspi.h>
+#include "../repository.h"
 
 #define HCAST(type, handle) ((type)(intptr_t)handle)
 
@@ -546,6 +548,7 @@ static int is_local_named_pipe_path(const char *filename)
 
 int mingw_open (const char *filename, int oflags, ...)
 {
+	static int append_atomically = -1;
 	typedef int (*open_fn_t)(wchar_t const *wfilename, int oflags, ...);
 	va_list args;
 	unsigned mode;
@@ -562,7 +565,16 @@ int mingw_open (const char *filename, int oflags, ...)
 		return -1;
 	}
 
-	if ((oflags & O_APPEND) && !is_local_named_pipe_path(filename))
+	/*
+	 * Only set append_atomically to default value(1) when repo is initialized
+	 * and fail to get config value
+	 */
+	if (append_atomically < 0 && the_repository && the_repository->commondir &&
+		git_config_get_bool("windows.appendatomically", &append_atomically))
+		append_atomically = 1;
+
+	if (append_atomically && (oflags & O_APPEND) &&
+		!is_local_named_pipe_path(filename))
 		open_fn = mingw_open_append;
 	else
 		open_fn = _wopen;
@@ -711,9 +723,28 @@ ssize_t mingw_write(int fd, const void *buf, size_t len)
 
 		/* check if fd is a pipe */
 		HANDLE h = (HANDLE) _get_osfhandle(fd);
-		if (GetFileType(h) != FILE_TYPE_PIPE)
+		if (GetFileType(h) != FILE_TYPE_PIPE) {
+			if (orig == EINVAL) {
+				wchar_t path[MAX_PATH];
+				DWORD ret = GetFinalPathNameByHandleW(h, path,
+								ARRAY_SIZE(path), 0);
+				UINT drive_type = ret > 0 && ret < ARRAY_SIZE(path) ?
+					GetDriveTypeW(path) : DRIVE_UNKNOWN;
+
+				/*
+				 * The default atomic append causes such an error on
+				 * network file systems, in such a case, it should be
+				 * turned off via config.
+				 *
+				 * `drive_type` of UNC path: DRIVE_NO_ROOT_DIR
+				 */
+				if (DRIVE_NO_ROOT_DIR == drive_type || DRIVE_REMOTE == drive_type)
+					warning("invalid write operation detected; you may try:\n"
+						"\n\tgit config windows.appendAtomically false");
+			}
+
 			errno = orig;
-		else if (orig == EINVAL)
+		} else if (orig == EINVAL)
 			errno = EPIPE;
 		else {
 			DWORD buf_size;

From 340965d2aaa03bbd660e9cadfb2459b120ea3d60 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 29 Mar 2022 12:05:18 +0200
Subject: [PATCH 099/259] vcxproj: allow building with `NO_PERL` again

This is another fall-out of the recent refactoring flurry.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 config.mak.uname | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/config.mak.uname b/config.mak.uname
index d9d750251bc2b9..0325d52da2968e 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -802,9 +802,11 @@ vcxproj:
 	sed -i '/^git_broken_path_fix ".*/d' git-sh-setup
 	git add -f $(SCRIPT_LIB) $(SCRIPTS)
 
+ifndef NO_PERL
 	# Add Perl module
 	$(MAKE) $(LIB_PERL_GEN)
 	git add -f perl/build
+endif
 
 	# Add bin-wrappers, for testing
 	rm -rf bin-wrappers/

From b399e4d7dbdd59c531ff75985e393825a0f5a002 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 28 Jun 2022 16:35:04 +0200
Subject: [PATCH 100/259] vcxproj: require C11

This fixes the build after 7bc341e21b (git-compat-util: add a test
balloon for C99 support, 2021-12-01).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 contrib/buildsystems/Generators/Vcxproj.pm | 1 +
 1 file changed, 1 insertion(+)

diff --git a/contrib/buildsystems/Generators/Vcxproj.pm b/contrib/buildsystems/Generators/Vcxproj.pm
index a6d1c6b8d05682..1858107378396a 100644
--- a/contrib/buildsystems/Generators/Vcxproj.pm
+++ b/contrib/buildsystems/Generators/Vcxproj.pm
@@ -178,6 +178,7 @@ sub createProject {
       <InlineFunctionExpansion>OnlyExplicitInline</InlineFunctionExpansion>
       <PrecompiledHeader />
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <LanguageStandard_C>stdc11</LanguageStandard_C>
     </ClCompile>
     <Lib>
       <SuppressStartupBanner>true</SuppressStartupBanner>

From da2f86c193fae0a26d1017d06c83199580644fec Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 28 Jun 2022 16:38:12 +0200
Subject: [PATCH 101/259] vcxproj: ignore the `-pedantic` option

This is now passed by default, ever since 6a8cbc41ba (developer: enable
pedantic by default, 2021-09-03).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 contrib/buildsystems/engine.pl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/contrib/buildsystems/engine.pl b/contrib/buildsystems/engine.pl
index 417ae71d44ccab..ee4fca200cc506 100755
--- a/contrib/buildsystems/engine.pl
+++ b/contrib/buildsystems/engine.pl
@@ -263,7 +263,7 @@ sub handleCompileLine
         if ("$part" eq "-o") {
             # ignore object file
             shift @parts;
-        } elsif ("$part" eq "-c" || "$part" eq "-i" || "$part" =~ /^-fno-/) {
+        } elsif ("$part" eq "-c" || "$part" eq "-i" || "$part" =~ /^-fno-/ || "$part" eq '-pedantic') {
             # ignore compile flag
         } elsif ($part =~ /^.?-I/) {
             push(@incpaths, $part);

From dae1de22ee8942f78a2b09804721020b3b5f814d Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 28 Jun 2022 17:00:59 +0200
Subject: [PATCH 102/259] vcxproj: include reftable when committing `.vcxproj`
 files

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 config.mak.uname | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/config.mak.uname b/config.mak.uname
index 0325d52da2968e..4271e70a11d128 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -770,7 +770,7 @@ vcxproj:
 
 	# Make .vcxproj files and add them
 	perl contrib/buildsystems/generate -g Vcxproj
-	git add -f git.sln {*,*/lib.proj,t/helper/*}/*.vcxproj
+	git add -f git.sln {*,*/lib.proj,t/helper/*,reftable/libreftable{,_test}.proj}/*.vcxproj
 
 	# Generate the LinkOrCopyBuiltins.targets and LinkOrCopyRemoteHttp.targets file
 	(echo '<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">' && \

From 22cf7921b8ebc06d0020cb08c1070f76eab9022a Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 28 Jun 2022 18:04:01 +0200
Subject: [PATCH 103/259] vcxproj: handle libreftable_test, too

Since ef8a6c6268 (reftable: utility functions, 2021-10-07) we not only
have a libreftable, but also a libreftable_test.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 contrib/buildsystems/Generators/Vcxproj.pm | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/contrib/buildsystems/Generators/Vcxproj.pm b/contrib/buildsystems/Generators/Vcxproj.pm
index 1858107378396a..20d91ea84bfd44 100644
--- a/contrib/buildsystems/Generators/Vcxproj.pm
+++ b/contrib/buildsystems/Generators/Vcxproj.pm
@@ -77,7 +77,7 @@ sub createProject {
     my $libs_release = "\n    ";
     my $libs_debug = "\n    ";
     if (!$static_library && $name ne 'headless-git') {
-      $libs_release = join(";", sort(grep /^(?!libgit\.lib|xdiff\/lib\.lib|vcs-svn\/lib\.lib|reftable\/libreftable\.lib)/, @{$$build_structure{"$prefix${name}_LIBS"}}));
+      $libs_release = join(";", sort(grep /^(?!libgit\.lib|xdiff\/lib\.lib|vcs-svn\/lib\.lib|reftable\/libreftable(_test)?\.lib)/, @{$$build_structure{"$prefix${name}_LIBS"}}));
       $libs_debug = $libs_release;
       $libs_debug =~ s/zlib\.lib/zlibd\.lib/g;
       $libs_debug =~ s/libexpat\.lib/libexpatd\.lib/g;
@@ -258,6 +258,7 @@ EOM
     if ((!$static_library || $target =~ 'vcs-svn' || $target =~ 'xdiff') && !($name =~ /headless-git/)) {
       my $uuid_libgit = $$build_structure{"LIBS_libgit_GUID"};
       my $uuid_libreftable = $$build_structure{"LIBS_reftable/libreftable_GUID"};
+      my $uuid_libreftable_test = $$build_structure{"LIBS_reftable/libreftable_test_GUID"};
       my $uuid_xdiff_lib = $$build_structure{"LIBS_xdiff/lib_GUID"};
 
       print F << "EOM";
@@ -269,10 +270,14 @@ EOM
 EOM
       if (!($name =~ /xdiff|libreftable/)) {
         print F << "EOM";
-    <ProjectReference Include="$cdup\\reftable\\libreftable\\libreftable.vcxproj">
+    <ProjectReference Include="$cdup\\reftable\\libreftable.proj\\libreftable.vcxproj">
       <Project>$uuid_libreftable</Project>
       <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
     </ProjectReference>
+    <ProjectReference Include="$cdup\\reftable\\libreftable_test.proj\\libreftable_test.vcxproj">
+      <Project>$uuid_libreftable_test</Project>
+      <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
+    </ProjectReference>
 EOM
       }
       if (!($name =~ 'xdiff')) {

From 2d16464a9fb918078adad3096e0aee9c171cf6d1 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 28 Jun 2022 17:36:21 +0200
Subject: [PATCH 104/259] vcxproj: avoid escaping double quotes in the defines

Visual Studio 2022 does not like that at all.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 contrib/buildsystems/Generators/Vcxproj.pm | 1 +
 1 file changed, 1 insertion(+)

diff --git a/contrib/buildsystems/Generators/Vcxproj.pm b/contrib/buildsystems/Generators/Vcxproj.pm
index 20d91ea84bfd44..bf77a44e11f463 100644
--- a/contrib/buildsystems/Generators/Vcxproj.pm
+++ b/contrib/buildsystems/Generators/Vcxproj.pm
@@ -88,6 +88,7 @@ sub createProject {
     $defines =~ s/</&lt;/g;
     $defines =~ s/>/&gt;/g;
     $defines =~ s/\'//g;
+    $defines =~ s/\\"/"/g;
 
     my $rcdefines = $defines;
     $rcdefines =~ s/(?<!\\)"/\\$&/g;

From ca249001ec8164edaed6c964bf1ce358286e2840 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sun, 10 Jul 2022 00:39:32 +0200
Subject: [PATCH 105/259] ci: adjust Azure Pipeline for `runs_on_pool`

These refactorings are really gifts that keep on giving.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 ci/lib.sh | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/ci/lib.sh b/ci/lib.sh
index 74b430be2387ac..d1d40991c4ba42 100755
--- a/ci/lib.sh
+++ b/ci/lib.sh
@@ -224,6 +224,12 @@ then
 
 	GIT_TEST_OPTS="--write-junit-xml"
 	JOBS=10
+	case "$CI_OS_NAME" in
+	linux) runs_on_pool=ubuntu-latest;;
+	macos|osx) runs_on_pool=macos-latest;;
+	windows_nt) runs_on_pool=windows-latest;;
+	*) echo "Unhandled OS: $CI_OS_NAME" >&2; exit 1;;
+	esac
 elif test true = "$GITHUB_ACTIONS"
 then
 	CI_TYPE=github-actions

From d43e0c8ed098f199c4a87780f87df4c2a40ec4a5 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sun, 10 Jul 2022 01:15:08 +0200
Subject: [PATCH 106/259] ci: stop linking the `prove` cache

It is not useful because we do not have any persisted directory anymore,
not since dropping our Travis CI support.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 ci/run-build-and-tests.sh | 5 -----
 ci/run-test-slice.sh      | 5 -----
 2 files changed, 10 deletions(-)

diff --git a/ci/run-build-and-tests.sh b/ci/run-build-and-tests.sh
index 98dda42045d3f3..2df089e69d6b30 100755
--- a/ci/run-build-and-tests.sh
+++ b/ci/run-build-and-tests.sh
@@ -5,11 +5,6 @@
 
 . ${0%/*}/lib.sh
 
-case "$CI_OS_NAME" in
-windows*) cmd //c mklink //j t\\.prove "$(cygpath -aw "$cache_dir/.prove")";;
-*) ln -s "$cache_dir/.prove" t/.prove;;
-esac
-
 run_tests=t
 
 case "$jobname" in
diff --git a/ci/run-test-slice.sh b/ci/run-test-slice.sh
index e167e646f79e3d..0444c79c023c82 100755
--- a/ci/run-test-slice.sh
+++ b/ci/run-test-slice.sh
@@ -5,11 +5,6 @@
 
 . ${0%/*}/lib.sh
 
-case "$CI_OS_NAME" in
-windows*) cmd //c mklink //j t\\.prove "$(cygpath -aw "$cache_dir/.prove")";;
-*) ln -s "$cache_dir/.prove" t/.prove;;
-esac
-
 group "Run tests" make --quiet -C t T="$(cd t &&
 	./helper/test-tool path-utils slice-tests "$1" "$2" t[0-9]*.sh |
 	tr '\n' ' ')" ||

From 800490f91431f51c7ffcc67dae1139a83c9189f8 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 11 Feb 2021 15:09:57 +0100
Subject: [PATCH 107/259] ci: reinstate Azure Pipelines support

... so that we can test a MinGit backport in a private repository (with
GitHub Actions, minutes and parallel jobs are limited way more than with
Azure Pipelines in private repositories).

In this commit, we reinstate the exact version of `azure-pipelines.yml`
as 6081d3898fe (ci: retire the Azure Pipelines definition, 2020-04-11)
deleted.

Naturally, many adjustments are required to make it work again. Some of
the changes are actually outside of that file (such as the
`runs_on_pool` changes that are needed in the Azure Pipelines part of
`ci/lib.sh`) and they were made in the commits leading up to this here
commit.

However, other adjustments are required in the `azure-pipelines.yml`
file itself, and for ease of review (read: to build confidence in those
changes) they will be made in subsequent, individual commits that
explain the intent, context, implementation and justification like every
good commit message should do.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 azure-pipelines.yml | 558 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 558 insertions(+)
 create mode 100644 azure-pipelines.yml

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
new file mode 100644
index 00000000000000..11413f66f89662
--- /dev/null
+++ b/azure-pipelines.yml
@@ -0,0 +1,558 @@
+variables:
+  Agent.Source.Git.ShallowFetchDepth: 1
+
+jobs:
+- job: windows_build
+  displayName: Windows Build
+  condition: succeeded()
+  pool:
+    vmImage: windows-latest
+  timeoutInMinutes: 240
+  steps:
+  - powershell: |
+      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
+        net use s: \\gitfileshare.file.core.windows.net\test-cache "$GITFILESHAREPWD" /user:AZURE\gitfileshare /persistent:no
+        cmd /c mklink /d "$(Build.SourcesDirectory)\test-cache" S:\
+      }
+    displayName: 'Mount test-cache'
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+  - powershell: |
+      $urlbase = "https://dev.azure.com/git-for-windows/git/_apis/build/builds"
+      $id = ((Invoke-WebRequest -UseBasicParsing "${urlbase}?definitions=22&statusFilter=completed&resultFilter=succeeded&`$top=1").content | ConvertFrom-JSON).value[0].id
+      $downloadUrl = ((Invoke-WebRequest -UseBasicParsing "${urlbase}/$id/artifacts").content | ConvertFrom-JSON).value[1].resource.downloadUrl
+      (New-Object Net.WebClient).DownloadFile($downloadUrl,"git-sdk-64-minimal.zip")
+      Expand-Archive git-sdk-64-minimal.zip -DestinationPath . -Force
+      Remove-Item git-sdk-64-minimal.zip
+
+      # Let Git ignore the SDK and the test-cache
+      "/git-sdk-64-minimal/`n/test-cache/`n" | Out-File -NoNewLine -Encoding ascii -Append "$(Build.SourcesDirectory)\.git\info\exclude"
+    displayName: 'Download git-sdk-64-minimal'
+  - powershell: |
+      & git-sdk-64-minimal\usr\bin\bash.exe -lc @"
+        ci/make-test-artifacts.sh artifacts
+      "@
+      if (!$?) { exit(1) }
+    displayName: Build
+    env:
+      HOME: $(Build.SourcesDirectory)
+      MSYSTEM: MINGW64
+      DEVELOPER: 1
+      NO_PERL: 1
+  - task: PublishPipelineArtifact@0
+    displayName: 'Publish Pipeline Artifact: test artifacts'
+    inputs:
+      artifactName: 'windows-artifacts'
+      targetPath: '$(Build.SourcesDirectory)\artifacts'
+  - task: PublishPipelineArtifact@0
+    displayName: 'Publish Pipeline Artifact: git-sdk-64-minimal'
+    inputs:
+      artifactName: 'git-sdk-64-minimal'
+      targetPath: '$(Build.SourcesDirectory)\git-sdk-64-minimal'
+  - powershell: |
+      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
+        cmd /c rmdir "$(Build.SourcesDirectory)\test-cache"
+      }
+    displayName: 'Unmount test-cache'
+    condition: true
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+
+- job: windows_test
+  displayName: Windows Test
+  dependsOn: windows_build
+  condition: succeeded()
+  pool:
+    vmImage: windows-latest
+  timeoutInMinutes: 240
+  strategy:
+    parallel: 10
+  steps:
+  - powershell: |
+      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
+        net use s: \\gitfileshare.file.core.windows.net\test-cache "$GITFILESHAREPWD" /user:AZURE\gitfileshare /persistent:no
+        cmd /c mklink /d "$(Build.SourcesDirectory)\test-cache" S:\
+      }
+    displayName: 'Mount test-cache'
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+  - task: DownloadPipelineArtifact@0
+    displayName: 'Download Pipeline Artifact: test artifacts'
+    inputs:
+      artifactName: 'windows-artifacts'
+      targetPath: '$(Build.SourcesDirectory)'
+  - task: DownloadPipelineArtifact@0
+    displayName: 'Download Pipeline Artifact: git-sdk-64-minimal'
+    inputs:
+      artifactName: 'git-sdk-64-minimal'
+      targetPath: '$(Build.SourcesDirectory)\git-sdk-64-minimal'
+  - powershell: |
+      & git-sdk-64-minimal\usr\bin\bash.exe -lc @"
+        test -f artifacts.tar.gz || {
+          echo No test artifacts found\; skipping >&2
+          exit 0
+        }
+        tar xf artifacts.tar.gz || exit 1
+
+        # Let Git ignore the SDK and the test-cache
+        printf '%s\n' /git-sdk-64-minimal/ /test-cache/ >>.git/info/exclude
+
+        ci/run-test-slice.sh `$SYSTEM_JOBPOSITIONINPHASE `$SYSTEM_TOTALJOBSINPHASE || {
+          ci/print-test-failures.sh
+          exit 1
+        }
+      "@
+      if (!$?) { exit(1) }
+    displayName: 'Test (parallel)'
+    env:
+      HOME: $(Build.SourcesDirectory)
+      MSYSTEM: MINGW64
+      NO_SVN_TESTS: 1
+      GIT_TEST_SKIP_REBASE_P: 1
+  - powershell: |
+      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
+        cmd /c rmdir "$(Build.SourcesDirectory)\test-cache"
+      }
+    displayName: 'Unmount test-cache'
+    condition: true
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+  - task: PublishTestResults@2
+    displayName: 'Publish Test Results **/TEST-*.xml'
+    inputs:
+      mergeTestResults: true
+      testRunTitle: 'windows'
+      platform: Windows
+      publishRunAttachments: false
+    condition: succeededOrFailed()
+  - task: PublishBuildArtifacts@1
+    displayName: 'Publish trash directories of failed tests'
+    condition: failed()
+    inputs:
+      PathtoPublish: t/failed-test-artifacts
+      ArtifactName: failed-test-artifacts
+
+- job: vs_build
+  displayName: Visual Studio Build
+  condition: succeeded()
+  pool:
+    vmImage: windows-latest
+  timeoutInMinutes: 240
+  steps:
+  - powershell: |
+      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
+        net use s: \\gitfileshare.file.core.windows.net\test-cache "$GITFILESHAREPWD" /user:AZURE\gitfileshare /persistent:no
+        cmd /c mklink /d "$(Build.SourcesDirectory)\test-cache" S:\
+      }
+    displayName: 'Mount test-cache'
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+  - powershell: |
+      $urlbase = "https://dev.azure.com/git-for-windows/git/_apis/build/builds"
+      $id = ((Invoke-WebRequest -UseBasicParsing "${urlbase}?definitions=22&statusFilter=completed&resultFilter=succeeded&`$top=1").content | ConvertFrom-JSON).value[0].id
+      $downloadUrl = ((Invoke-WebRequest -UseBasicParsing "${urlbase}/$id/artifacts").content | ConvertFrom-JSON).value[1].resource.downloadUrl
+      (New-Object Net.WebClient).DownloadFile($downloadUrl,"git-sdk-64-minimal.zip")
+      Expand-Archive git-sdk-64-minimal.zip -DestinationPath . -Force
+      Remove-Item git-sdk-64-minimal.zip
+
+      # Let Git ignore the SDK and the test-cache
+      "/git-sdk-64-minimal/`n/test-cache/`n" | Out-File -NoNewLine -Encoding ascii -Append "$(Build.SourcesDirectory)\.git\info\exclude"
+    displayName: 'Download git-sdk-64-minimal'
+  - powershell: |
+      & git-sdk-64-minimal\usr\bin\bash.exe -lc @"
+        make NDEBUG=1 DEVELOPER=1 vcxproj
+      "@
+      if (!$?) { exit(1) }
+    displayName: Generate Visual Studio Solution
+    env:
+      HOME: $(Build.SourcesDirectory)
+      MSYSTEM: MINGW64
+      DEVELOPER: 1
+      NO_PERL: 1
+      GIT_CONFIG_PARAMETERS: "'user.name=CI' 'user.email=ci@git'"
+  - powershell: |
+      $urlbase = "https://dev.azure.com/git/git/_apis/build/builds"
+      $id = ((Invoke-WebRequest -UseBasicParsing "${urlbase}?definitions=9&statusFilter=completed&resultFilter=succeeded&`$top=1").content | ConvertFrom-JSON).value[0].id
+      $downloadUrl = ((Invoke-WebRequest -UseBasicParsing "${urlbase}/$id/artifacts").content | ConvertFrom-JSON).value[0].resource.downloadUrl
+      (New-Object Net.WebClient).DownloadFile($downloadUrl, "compat.zip")
+      Expand-Archive compat.zip -DestinationPath . -Force
+      Remove-Item compat.zip
+    displayName: 'Download vcpkg artifacts'
+  - task: MSBuild@1
+    inputs:
+      solution: git.sln
+      platform: x64
+      configuration: Release
+      maximumCpuCount: 4
+      msbuildArguments: /p:PlatformToolset=v142
+  - powershell: |
+      & compat\vcbuild\vcpkg_copy_dlls.bat release
+      if (!$?) { exit(1) }
+      & git-sdk-64-minimal\usr\bin\bash.exe -lc @"
+        mkdir -p artifacts &&
+        eval \"`$(make -n artifacts-tar INCLUDE_DLLS_IN_ARTIFACTS=YesPlease ARTIFACTS_DIRECTORY=artifacts | grep ^tar)\"
+      "@
+      if (!$?) { exit(1) }
+    displayName: Bundle artifact tar
+    env:
+      HOME: $(Build.SourcesDirectory)
+      MSYSTEM: MINGW64
+      DEVELOPER: 1
+      NO_PERL: 1
+      MSVC: 1
+      VCPKG_ROOT: $(Build.SourcesDirectory)\compat\vcbuild\vcpkg
+  - powershell: |
+      $tag = (Invoke-WebRequest -UseBasicParsing "https://gitforwindows.org/latest-tag.txt").content
+      $version = (Invoke-WebRequest -UseBasicParsing "https://gitforwindows.org/latest-version.txt").content
+      $url = "https://github.com/git-for-windows/git/releases/download/${tag}/PortableGit-${version}-64-bit.7z.exe"
+      (New-Object Net.WebClient).DownloadFile($url,"PortableGit.exe")
+      & .\PortableGit.exe -y -oartifacts\PortableGit
+      # Wait until it is unpacked
+      while (-not @(Remove-Item -ErrorAction SilentlyContinue PortableGit.exe; $?)) { sleep 1 }
+    displayName: Download & extract portable Git
+  - task: PublishPipelineArtifact@0
+    displayName: 'Publish Pipeline Artifact: MSVC test artifacts'
+    inputs:
+      artifactName: 'vs-artifacts'
+      targetPath: '$(Build.SourcesDirectory)\artifacts'
+  - powershell: |
+      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
+        cmd /c rmdir "$(Build.SourcesDirectory)\test-cache"
+      }
+    displayName: 'Unmount test-cache'
+    condition: true
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+
+- job: vs_test
+  displayName: Visual Studio Test
+  dependsOn: vs_build
+  condition: succeeded()
+  pool:
+    vmImage: windows-latest
+  timeoutInMinutes: 240
+  strategy:
+    parallel: 10
+  steps:
+  - powershell: |
+      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
+        net use s: \\gitfileshare.file.core.windows.net\test-cache "$GITFILESHAREPWD" /user:AZURE\gitfileshare /persistent:no
+        cmd /c mklink /d "$(Build.SourcesDirectory)\test-cache" S:\
+      }
+    displayName: 'Mount test-cache'
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+  - task: DownloadPipelineArtifact@0
+    displayName: 'Download Pipeline Artifact: VS test artifacts'
+    inputs:
+      artifactName: 'vs-artifacts'
+      targetPath: '$(Build.SourcesDirectory)'
+  - powershell: |
+      & PortableGit\git-cmd.exe --command=usr\bin\bash.exe -lc @"
+        test -f artifacts.tar.gz || {
+          echo No test artifacts found\; skipping >&2
+          exit 0
+        }
+        tar xf artifacts.tar.gz || exit 1
+
+        # Let Git ignore the SDK and the test-cache
+        printf '%s\n' /PortableGit/ /test-cache/ >>.git/info/exclude
+
+        cd t &&
+        PATH=\"`$PWD/helper:`$PATH\" &&
+        test-tool.exe run-command testsuite --jobs=10 -V -x --write-junit-xml \
+                `$(test-tool.exe path-utils slice-tests \
+                        `$SYSTEM_JOBPOSITIONINPHASE `$SYSTEM_TOTALJOBSINPHASE t[0-9]*.sh)
+      "@
+      if (!$?) { exit(1) }
+    displayName: 'Test (parallel)'
+    env:
+      HOME: $(Build.SourcesDirectory)
+      MSYSTEM: MINGW64
+      NO_SVN_TESTS: 1
+      GIT_TEST_SKIP_REBASE_P: 1
+  - powershell: |
+      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
+        cmd /c rmdir "$(Build.SourcesDirectory)\test-cache"
+      }
+    displayName: 'Unmount test-cache'
+    condition: true
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+  - task: PublishTestResults@2
+    displayName: 'Publish Test Results **/TEST-*.xml'
+    inputs:
+      mergeTestResults: true
+      testRunTitle: 'vs'
+      platform: Windows
+      publishRunAttachments: false
+    condition: succeededOrFailed()
+  - task: PublishBuildArtifacts@1
+    displayName: 'Publish trash directories of failed tests'
+    condition: failed()
+    inputs:
+      PathtoPublish: t/failed-test-artifacts
+      ArtifactName: failed-vs-test-artifacts
+
+- job: linux_clang
+  displayName: linux-clang
+  condition: succeeded()
+  pool:
+    vmImage: ubuntu-latest
+  steps:
+  - bash: |
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
+
+       sudo apt-get update &&
+       sudo apt-get -y install git gcc make libssl-dev libcurl4-openssl-dev libexpat-dev tcl tk gettext git-email zlib1g-dev apache2-bin &&
+
+       export CC=clang || exit 1
+
+       ci/install-dependencies.sh || exit 1
+       ci/run-build-and-tests.sh || {
+           ci/print-test-failures.sh
+           exit 1
+       }
+
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || sudo umount "$HOME/test-cache" || exit 1
+    displayName: 'ci/run-build-and-tests.sh'
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+  - task: PublishTestResults@2
+    displayName: 'Publish Test Results **/TEST-*.xml'
+    inputs:
+      mergeTestResults: true
+      testRunTitle: 'linux-clang'
+      platform: Linux
+      publishRunAttachments: false
+    condition: succeededOrFailed()
+  - task: PublishBuildArtifacts@1
+    displayName: 'Publish trash directories of failed tests'
+    condition: failed()
+    inputs:
+      PathtoPublish: t/failed-test-artifacts
+      ArtifactName: failed-test-artifacts
+
+- job: linux_gcc
+  displayName: linux-gcc
+  condition: succeeded()
+  pool:
+    vmImage: ubuntu-latest
+  steps:
+  - bash: |
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
+
+       sudo add-apt-repository ppa:ubuntu-toolchain-r/test &&
+       sudo apt-get update &&
+       sudo apt-get -y install git gcc make libssl-dev libcurl4-openssl-dev libexpat-dev tcl tk gettext git-email zlib1g-dev apache2 language-pack-is git-svn gcc-8 || exit 1
+
+       ci/install-dependencies.sh || exit 1
+       ci/run-build-and-tests.sh || {
+           ci/print-test-failures.sh
+           exit 1
+       }
+
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || sudo umount "$HOME/test-cache" || exit 1
+    displayName: 'ci/run-build-and-tests.sh'
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+  - task: PublishTestResults@2
+    displayName: 'Publish Test Results **/TEST-*.xml'
+    inputs:
+      mergeTestResults: true
+      testRunTitle: 'linux-gcc'
+      platform: Linux
+      publishRunAttachments: false
+    condition: succeededOrFailed()
+  - task: PublishBuildArtifacts@1
+    displayName: 'Publish trash directories of failed tests'
+    condition: failed()
+    inputs:
+      PathtoPublish: t/failed-test-artifacts
+      ArtifactName: failed-test-artifacts
+
+- job: osx_clang
+  displayName: osx-clang
+  condition: succeeded()
+  pool:
+    vmImage: macOS-latest
+  steps:
+  - bash: |
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
+
+       export CC=clang
+
+       ci/install-dependencies.sh || exit 1
+       ci/run-build-and-tests.sh || {
+           ci/print-test-failures.sh
+           exit 1
+       }
+
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || umount "$HOME/test-cache" || exit 1
+    displayName: 'ci/run-build-and-tests.sh'
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+  - task: PublishTestResults@2
+    displayName: 'Publish Test Results **/TEST-*.xml'
+    inputs:
+      mergeTestResults: true
+      testRunTitle: 'osx-clang'
+      platform: macOS
+      publishRunAttachments: false
+    condition: succeededOrFailed()
+  - task: PublishBuildArtifacts@1
+    displayName: 'Publish trash directories of failed tests'
+    condition: failed()
+    inputs:
+      PathtoPublish: t/failed-test-artifacts
+      ArtifactName: failed-test-artifacts
+
+- job: osx_gcc
+  displayName: osx-gcc
+  condition: succeeded()
+  pool:
+    vmImage: macOS-latest
+  steps:
+  - bash: |
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
+
+       ci/install-dependencies.sh || exit 1
+       ci/run-build-and-tests.sh || {
+           ci/print-test-failures.sh
+           exit 1
+       }
+
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || umount "$HOME/test-cache" || exit 1
+    displayName: 'ci/run-build-and-tests.sh'
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+  - task: PublishTestResults@2
+    displayName: 'Publish Test Results **/TEST-*.xml'
+    inputs:
+      mergeTestResults: true
+      testRunTitle: 'osx-gcc'
+      platform: macOS
+      publishRunAttachments: false
+    condition: succeededOrFailed()
+  - task: PublishBuildArtifacts@1
+    displayName: 'Publish trash directories of failed tests'
+    condition: failed()
+    inputs:
+      PathtoPublish: t/failed-test-artifacts
+      ArtifactName: failed-test-artifacts
+
+- job: gettext_poison
+  displayName: GETTEXT_POISON
+  condition: succeeded()
+  pool:
+    vmImage: ubuntu-latest
+  steps:
+  - bash: |
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
+
+       sudo apt-get update &&
+       sudo apt-get -y install git gcc make libssl-dev libcurl4-openssl-dev libexpat-dev tcl tk gettext git-email zlib1g-dev &&
+
+       export jobname=GETTEXT_POISON || exit 1
+
+       ci/run-build-and-tests.sh || {
+           ci/print-test-failures.sh
+           exit 1
+       }
+
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || sudo umount "$HOME/test-cache" || exit 1
+    displayName: 'ci/run-build-and-tests.sh'
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+  - task: PublishTestResults@2
+    displayName: 'Publish Test Results **/TEST-*.xml'
+    inputs:
+      mergeTestResults: true
+      testRunTitle: 'gettext-poison'
+      platform: Linux
+      publishRunAttachments: false
+    condition: succeededOrFailed()
+  - task: PublishBuildArtifacts@1
+    displayName: 'Publish trash directories of failed tests'
+    condition: failed()
+    inputs:
+      PathtoPublish: t/failed-test-artifacts
+      ArtifactName: failed-test-artifacts
+
+- job: linux32
+  displayName: Linux32
+  condition: succeeded()
+  pool:
+    vmImage: ubuntu-latest
+  steps:
+  - bash: |
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
+
+       res=0
+       sudo AGENT_OS="$AGENT_OS" BUILD_BUILDNUMBER="$BUILD_BUILDNUMBER" BUILD_REPOSITORY_URI="$BUILD_REPOSITORY_URI" BUILD_SOURCEBRANCH="$BUILD_SOURCEBRANCH" BUILD_SOURCEVERSION="$BUILD_SOURCEVERSION" SYSTEM_PHASENAME="$SYSTEM_PHASENAME" SYSTEM_TASKDEFINITIONSURI="$SYSTEM_TASKDEFINITIONSURI" SYSTEM_TEAMPROJECT="$SYSTEM_TEAMPROJECT" CC=$CC MAKEFLAGS="$MAKEFLAGS" jobname=Linux32 bash -lxc ci/run-docker.sh || res=1
+
+       sudo chmod a+r t/out/TEST-*.xml
+       test ! -d t/failed-test-artifacts || sudo chmod a+r t/failed-test-artifacts
+
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || sudo umount "$HOME/test-cache" || res=1
+       exit $res
+    displayName: 'jobname=Linux32 ci/run-docker.sh'
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+  - task: PublishTestResults@2
+    displayName: 'Publish Test Results **/TEST-*.xml'
+    inputs:
+      mergeTestResults: true
+      testRunTitle: 'linux32'
+      platform: Linux
+      publishRunAttachments: false
+    condition: succeededOrFailed()
+  - task: PublishBuildArtifacts@1
+    displayName: 'Publish trash directories of failed tests'
+    condition: failed()
+    inputs:
+      PathtoPublish: t/failed-test-artifacts
+      ArtifactName: failed-test-artifacts
+
+- job: static_analysis
+  displayName: StaticAnalysis
+  condition: succeeded()
+  pool:
+    vmImage: ubuntu-latest
+  steps:
+  - bash: |
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
+
+       sudo apt-get update &&
+       sudo apt-get install -y coccinelle libcurl4-openssl-dev libssl-dev libexpat-dev gettext &&
+
+       export jobname=StaticAnalysis &&
+
+       ci/run-static-analysis.sh || exit 1
+
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || sudo umount "$HOME/test-cache" || exit 1
+    displayName: 'ci/run-static-analysis.sh'
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)
+
+- job: documentation
+  displayName: Documentation
+  condition: succeeded()
+  pool:
+    vmImage: ubuntu-latest
+  steps:
+  - bash: |
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
+
+       sudo apt-get update &&
+       sudo apt-get install -y asciidoc xmlto asciidoctor docbook-xsl-ns &&
+
+       export ALREADY_HAVE_ASCIIDOCTOR=yes. &&
+       export jobname=Documentation &&
+
+       ci/test-documentation.sh || exit 1
+
+       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || sudo umount "$HOME/test-cache" || exit 1
+    displayName: 'ci/test-documentation.sh'
+    env:
+      GITFILESHAREPWD: $(gitfileshare.pwd)

From a599e1bfb4a24efd8db3f404a092cd22a233cb34 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 29 Mar 2022 13:42:19 +0200
Subject: [PATCH 108/259] azure-pipeline: drop the `GETTEXT_POISON` job

This is a follow-up to 6c280b4142 (ci: remove GETTEXT_POISON jobs,
2021-01-20) after reinstating the Azure Pipeline.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 azure-pipelines.yml | 38 --------------------------------------
 1 file changed, 38 deletions(-)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index 11413f66f89662..7b20ad2667fdc9 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -441,44 +441,6 @@ jobs:
       PathtoPublish: t/failed-test-artifacts
       ArtifactName: failed-test-artifacts
 
-- job: gettext_poison
-  displayName: GETTEXT_POISON
-  condition: succeeded()
-  pool:
-    vmImage: ubuntu-latest
-  steps:
-  - bash: |
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
-
-       sudo apt-get update &&
-       sudo apt-get -y install git gcc make libssl-dev libcurl4-openssl-dev libexpat-dev tcl tk gettext git-email zlib1g-dev &&
-
-       export jobname=GETTEXT_POISON || exit 1
-
-       ci/run-build-and-tests.sh || {
-           ci/print-test-failures.sh
-           exit 1
-       }
-
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || sudo umount "$HOME/test-cache" || exit 1
-    displayName: 'ci/run-build-and-tests.sh'
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
-  - task: PublishTestResults@2
-    displayName: 'Publish Test Results **/TEST-*.xml'
-    inputs:
-      mergeTestResults: true
-      testRunTitle: 'gettext-poison'
-      platform: Linux
-      publishRunAttachments: false
-    condition: succeededOrFailed()
-  - task: PublishBuildArtifacts@1
-    displayName: 'Publish trash directories of failed tests'
-    condition: failed()
-    inputs:
-      PathtoPublish: t/failed-test-artifacts
-      ArtifactName: failed-test-artifacts
-
 - job: linux32
   displayName: Linux32
   condition: succeeded()

From 1fa3babf6c30c812874e75a6ce90952eae90d809 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 29 Mar 2022 12:28:12 +0200
Subject: [PATCH 109/259] azure-pipeline: stop hard-coding `apt-get` calls

We have `ci/install-dependencies.sh` for that. Incidentally, this avoids
the following error in the linux-* jobs:

    The following packages have unmet dependencies:
    git-email : Depends: git (< 1:2.25.1-.) but 1:2.35.1-0ppa1~ubuntu20.04.1 is to be installed
	  Recommends: libemail-valid-perl but it is not going to be installed

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 azure-pipelines.yml | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index 7b20ad2667fdc9..e311d3055e5eca 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -303,9 +303,6 @@ jobs:
   - bash: |
        test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
 
-       sudo apt-get update &&
-       sudo apt-get -y install git gcc make libssl-dev libcurl4-openssl-dev libexpat-dev tcl tk gettext git-email zlib1g-dev apache2-bin &&
-
        export CC=clang || exit 1
 
        ci/install-dependencies.sh || exit 1
@@ -342,10 +339,6 @@ jobs:
   - bash: |
        test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
 
-       sudo add-apt-repository ppa:ubuntu-toolchain-r/test &&
-       sudo apt-get update &&
-       sudo apt-get -y install git gcc make libssl-dev libcurl4-openssl-dev libexpat-dev tcl tk gettext git-email zlib1g-dev apache2 language-pack-is git-svn gcc-8 || exit 1
-
        ci/install-dependencies.sh || exit 1
        ci/run-build-and-tests.sh || {
            ci/print-test-failures.sh

From 2fa96e03951573362a9d032b4e11c8d1d66c334b Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sun, 10 Jul 2022 00:02:30 +0200
Subject: [PATCH 110/259] azure-pipeline: drop the code to write to/read from a
 file share

We haven't used this feature in ages, we don't actually need to.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 azure-pipelines.yml | 105 --------------------------------------------
 1 file changed, 105 deletions(-)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index e311d3055e5eca..94bc7ea1f51b47 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -9,14 +9,6 @@ jobs:
     vmImage: windows-latest
   timeoutInMinutes: 240
   steps:
-  - powershell: |
-      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
-        net use s: \\gitfileshare.file.core.windows.net\test-cache "$GITFILESHAREPWD" /user:AZURE\gitfileshare /persistent:no
-        cmd /c mklink /d "$(Build.SourcesDirectory)\test-cache" S:\
-      }
-    displayName: 'Mount test-cache'
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
   - powershell: |
       $urlbase = "https://dev.azure.com/git-for-windows/git/_apis/build/builds"
       $id = ((Invoke-WebRequest -UseBasicParsing "${urlbase}?definitions=22&statusFilter=completed&resultFilter=succeeded&`$top=1").content | ConvertFrom-JSON).value[0].id
@@ -49,14 +41,6 @@ jobs:
     inputs:
       artifactName: 'git-sdk-64-minimal'
       targetPath: '$(Build.SourcesDirectory)\git-sdk-64-minimal'
-  - powershell: |
-      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
-        cmd /c rmdir "$(Build.SourcesDirectory)\test-cache"
-      }
-    displayName: 'Unmount test-cache'
-    condition: true
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
 
 - job: windows_test
   displayName: Windows Test
@@ -68,14 +52,6 @@ jobs:
   strategy:
     parallel: 10
   steps:
-  - powershell: |
-      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
-        net use s: \\gitfileshare.file.core.windows.net\test-cache "$GITFILESHAREPWD" /user:AZURE\gitfileshare /persistent:no
-        cmd /c mklink /d "$(Build.SourcesDirectory)\test-cache" S:\
-      }
-    displayName: 'Mount test-cache'
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
   - task: DownloadPipelineArtifact@0
     displayName: 'Download Pipeline Artifact: test artifacts'
     inputs:
@@ -109,14 +85,6 @@ jobs:
       MSYSTEM: MINGW64
       NO_SVN_TESTS: 1
       GIT_TEST_SKIP_REBASE_P: 1
-  - powershell: |
-      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
-        cmd /c rmdir "$(Build.SourcesDirectory)\test-cache"
-      }
-    displayName: 'Unmount test-cache'
-    condition: true
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
   - task: PublishTestResults@2
     displayName: 'Publish Test Results **/TEST-*.xml'
     inputs:
@@ -139,14 +107,6 @@ jobs:
     vmImage: windows-latest
   timeoutInMinutes: 240
   steps:
-  - powershell: |
-      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
-        net use s: \\gitfileshare.file.core.windows.net\test-cache "$GITFILESHAREPWD" /user:AZURE\gitfileshare /persistent:no
-        cmd /c mklink /d "$(Build.SourcesDirectory)\test-cache" S:\
-      }
-    displayName: 'Mount test-cache'
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
   - powershell: |
       $urlbase = "https://dev.azure.com/git-for-windows/git/_apis/build/builds"
       $id = ((Invoke-WebRequest -UseBasicParsing "${urlbase}?definitions=22&statusFilter=completed&resultFilter=succeeded&`$top=1").content | ConvertFrom-JSON).value[0].id
@@ -215,14 +175,6 @@ jobs:
     inputs:
       artifactName: 'vs-artifacts'
       targetPath: '$(Build.SourcesDirectory)\artifacts'
-  - powershell: |
-      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
-        cmd /c rmdir "$(Build.SourcesDirectory)\test-cache"
-      }
-    displayName: 'Unmount test-cache'
-    condition: true
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
 
 - job: vs_test
   displayName: Visual Studio Test
@@ -234,14 +186,6 @@ jobs:
   strategy:
     parallel: 10
   steps:
-  - powershell: |
-      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
-        net use s: \\gitfileshare.file.core.windows.net\test-cache "$GITFILESHAREPWD" /user:AZURE\gitfileshare /persistent:no
-        cmd /c mklink /d "$(Build.SourcesDirectory)\test-cache" S:\
-      }
-    displayName: 'Mount test-cache'
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
   - task: DownloadPipelineArtifact@0
     displayName: 'Download Pipeline Artifact: VS test artifacts'
     inputs:
@@ -271,14 +215,6 @@ jobs:
       MSYSTEM: MINGW64
       NO_SVN_TESTS: 1
       GIT_TEST_SKIP_REBASE_P: 1
-  - powershell: |
-      if ("$GITFILESHAREPWD" -ne "" -and "$GITFILESHAREPWD" -ne "`$`(gitfileshare.pwd)") {
-        cmd /c rmdir "$(Build.SourcesDirectory)\test-cache"
-      }
-    displayName: 'Unmount test-cache'
-    condition: true
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
   - task: PublishTestResults@2
     displayName: 'Publish Test Results **/TEST-*.xml'
     inputs:
@@ -301,8 +237,6 @@ jobs:
     vmImage: ubuntu-latest
   steps:
   - bash: |
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
-
        export CC=clang || exit 1
 
        ci/install-dependencies.sh || exit 1
@@ -310,11 +244,7 @@ jobs:
            ci/print-test-failures.sh
            exit 1
        }
-
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || sudo umount "$HOME/test-cache" || exit 1
     displayName: 'ci/run-build-and-tests.sh'
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
   - task: PublishTestResults@2
     displayName: 'Publish Test Results **/TEST-*.xml'
     inputs:
@@ -337,18 +267,12 @@ jobs:
     vmImage: ubuntu-latest
   steps:
   - bash: |
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
-
        ci/install-dependencies.sh || exit 1
        ci/run-build-and-tests.sh || {
            ci/print-test-failures.sh
            exit 1
        }
-
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || sudo umount "$HOME/test-cache" || exit 1
     displayName: 'ci/run-build-and-tests.sh'
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
   - task: PublishTestResults@2
     displayName: 'Publish Test Results **/TEST-*.xml'
     inputs:
@@ -371,8 +295,6 @@ jobs:
     vmImage: macOS-latest
   steps:
   - bash: |
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
-
        export CC=clang
 
        ci/install-dependencies.sh || exit 1
@@ -380,11 +302,7 @@ jobs:
            ci/print-test-failures.sh
            exit 1
        }
-
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || umount "$HOME/test-cache" || exit 1
     displayName: 'ci/run-build-and-tests.sh'
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
   - task: PublishTestResults@2
     displayName: 'Publish Test Results **/TEST-*.xml'
     inputs:
@@ -407,18 +325,12 @@ jobs:
     vmImage: macOS-latest
   steps:
   - bash: |
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
-
        ci/install-dependencies.sh || exit 1
        ci/run-build-and-tests.sh || {
            ci/print-test-failures.sh
            exit 1
        }
-
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || umount "$HOME/test-cache" || exit 1
     displayName: 'ci/run-build-and-tests.sh'
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
   - task: PublishTestResults@2
     displayName: 'Publish Test Results **/TEST-*.xml'
     inputs:
@@ -441,19 +353,14 @@ jobs:
     vmImage: ubuntu-latest
   steps:
   - bash: |
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
-
        res=0
        sudo AGENT_OS="$AGENT_OS" BUILD_BUILDNUMBER="$BUILD_BUILDNUMBER" BUILD_REPOSITORY_URI="$BUILD_REPOSITORY_URI" BUILD_SOURCEBRANCH="$BUILD_SOURCEBRANCH" BUILD_SOURCEVERSION="$BUILD_SOURCEVERSION" SYSTEM_PHASENAME="$SYSTEM_PHASENAME" SYSTEM_TASKDEFINITIONSURI="$SYSTEM_TASKDEFINITIONSURI" SYSTEM_TEAMPROJECT="$SYSTEM_TEAMPROJECT" CC=$CC MAKEFLAGS="$MAKEFLAGS" jobname=Linux32 bash -lxc ci/run-docker.sh || res=1
 
        sudo chmod a+r t/out/TEST-*.xml
        test ! -d t/failed-test-artifacts || sudo chmod a+r t/failed-test-artifacts
 
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || sudo umount "$HOME/test-cache" || res=1
        exit $res
     displayName: 'jobname=Linux32 ci/run-docker.sh'
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
   - task: PublishTestResults@2
     displayName: 'Publish Test Results **/TEST-*.xml'
     inputs:
@@ -476,19 +383,13 @@ jobs:
     vmImage: ubuntu-latest
   steps:
   - bash: |
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
-
        sudo apt-get update &&
        sudo apt-get install -y coccinelle libcurl4-openssl-dev libssl-dev libexpat-dev gettext &&
 
        export jobname=StaticAnalysis &&
 
        ci/run-static-analysis.sh || exit 1
-
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || sudo umount "$HOME/test-cache" || exit 1
     displayName: 'ci/run-static-analysis.sh'
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)
 
 - job: documentation
   displayName: Documentation
@@ -497,8 +398,6 @@ jobs:
     vmImage: ubuntu-latest
   steps:
   - bash: |
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || ci/mount-fileshare.sh //gitfileshare.file.core.windows.net/test-cache gitfileshare "$GITFILESHAREPWD" "$HOME/test-cache" || exit 1
-
        sudo apt-get update &&
        sudo apt-get install -y asciidoc xmlto asciidoctor docbook-xsl-ns &&
 
@@ -506,8 +405,4 @@ jobs:
        export jobname=Documentation &&
 
        ci/test-documentation.sh || exit 1
-
-       test "$GITFILESHAREPWD" = '$(gitfileshare.pwd)' || sudo umount "$HOME/test-cache" || exit 1
     displayName: 'ci/test-documentation.sh'
-    env:
-      GITFILESHAREPWD: $(gitfileshare.pwd)

From f10d16014f3e89eb1eede207cc7f3d354104b799 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sun, 10 Jul 2022 00:14:53 +0200
Subject: [PATCH 111/259] azure-pipeline: use partial clone/parallel checkout
 to initialize minimal-sdk

The Azure Pipeline `git-sdk-64-minimal` was retired...

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 azure-pipelines.yml | 125 +++++++++++++++++++-------------------------
 1 file changed, 55 insertions(+), 70 deletions(-)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index 94bc7ea1f51b47..f11f1342cd080b 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -1,5 +1,6 @@
 variables:
   Agent.Source.Git.ShallowFetchDepth: 1
+  GIT_CONFIG_PARAMETERS: "'checkout.workers=56' 'user.name=CI' 'user.email=ci@git'"
 
 jobs:
 - job: windows_build
@@ -9,28 +10,24 @@ jobs:
     vmImage: windows-latest
   timeoutInMinutes: 240
   steps:
-  - powershell: |
-      $urlbase = "https://dev.azure.com/git-for-windows/git/_apis/build/builds"
-      $id = ((Invoke-WebRequest -UseBasicParsing "${urlbase}?definitions=22&statusFilter=completed&resultFilter=succeeded&`$top=1").content | ConvertFrom-JSON).value[0].id
-      $downloadUrl = ((Invoke-WebRequest -UseBasicParsing "${urlbase}/$id/artifacts").content | ConvertFrom-JSON).value[1].resource.downloadUrl
-      (New-Object Net.WebClient).DownloadFile($downloadUrl,"git-sdk-64-minimal.zip")
-      Expand-Archive git-sdk-64-minimal.zip -DestinationPath . -Force
-      Remove-Item git-sdk-64-minimal.zip
-
+  - bash: git clone --bare --depth=1 --filter=blob:none --single-branch -b main https://github.com/git-for-windows/git-sdk-64
+    displayName: 'clone git-sdk-64'
+  - bash: git clone --depth=1 --single-branch -b main https://github.com/git-for-windows/build-extra
+    displayName: 'clone build-extra'
+  - bash: sh -x ./build-extra/please.sh create-sdk-artifact --sdk=git-sdk-64.git --out=git-sdk-64-minimal minimal-sdk
+    displayName: 'build git-sdk-64-minimal-sdk'
+  - bash: |
       # Let Git ignore the SDK and the test-cache
-      "/git-sdk-64-minimal/`n/test-cache/`n" | Out-File -NoNewLine -Encoding ascii -Append "$(Build.SourcesDirectory)\.git\info\exclude"
-    displayName: 'Download git-sdk-64-minimal'
-  - powershell: |
-      & git-sdk-64-minimal\usr\bin\bash.exe -lc @"
-        ci/make-test-artifacts.sh artifacts
-      "@
-      if (!$?) { exit(1) }
+      printf "%s\n" /git-sdk-64.git/ /build-extra/ /git-sdk-64-minimal/ /test-cache/ >>'.git/info/exclude'
+    displayName: 'Ignore untracked directories'
+  - bash: ci/make-test-artifacts.sh artifacts
     displayName: Build
     env:
       HOME: $(Build.SourcesDirectory)
       MSYSTEM: MINGW64
       DEVELOPER: 1
       NO_PERL: 1
+      PATH: "$(Build.SourcesDirectory)\\git-sdk-64-minimal\\mingw64\\bin;$(Build.SourcesDirectory)\\git-sdk-64-minimal\\usr\\bin;C:\\Windows\\system32;C:\\Windows;C:\\Windows\\system32\\wbem"
   - task: PublishPipelineArtifact@0
     displayName: 'Publish Pipeline Artifact: test artifacts'
     inputs:
@@ -62,29 +59,27 @@ jobs:
     inputs:
       artifactName: 'git-sdk-64-minimal'
       targetPath: '$(Build.SourcesDirectory)\git-sdk-64-minimal'
-  - powershell: |
-      & git-sdk-64-minimal\usr\bin\bash.exe -lc @"
-        test -f artifacts.tar.gz || {
-          echo No test artifacts found\; skipping >&2
-          exit 0
-        }
-        tar xf artifacts.tar.gz || exit 1
+  - bash: |
+      test -f artifacts.tar.gz || {
+        echo No test artifacts found\; skipping >&2
+        exit 0
+      }
+      tar xf artifacts.tar.gz || exit 1
 
-        # Let Git ignore the SDK and the test-cache
-        printf '%s\n' /git-sdk-64-minimal/ /test-cache/ >>.git/info/exclude
+      # Let Git ignore the SDK and the test-cache
+      printf '%s\n' /git-sdk-64.git/ /build-extra/ /git-sdk-64-minimal/ /test-cache/ >>.git/info/exclude
 
-        ci/run-test-slice.sh `$SYSTEM_JOBPOSITIONINPHASE `$SYSTEM_TOTALJOBSINPHASE || {
-          ci/print-test-failures.sh
-          exit 1
-        }
-      "@
-      if (!$?) { exit(1) }
+      ci/run-test-slice.sh $SYSTEM_JOBPOSITIONINPHASE $SYSTEM_TOTALJOBSINPHASE || {
+        ci/print-test-failures.sh
+        exit 1
+      }
     displayName: 'Test (parallel)'
     env:
       HOME: $(Build.SourcesDirectory)
       MSYSTEM: MINGW64
       NO_SVN_TESTS: 1
       GIT_TEST_SKIP_REBASE_P: 1
+      PATH: "$(Build.SourcesDirectory)\\git-sdk-64-minimal\\mingw64\\bin;$(Build.SourcesDirectory)\\git-sdk-64-minimal\\usr\\bin\\core_perl;$(Build.SourcesDirectory)\\git-sdk-64-minimal\\usr\\bin;C:\\Windows\\system32;C:\\Windows;C:\\Windows\\system32\\wbem"
   - task: PublishTestResults@2
     displayName: 'Publish Test Results **/TEST-*.xml'
     inputs:
@@ -107,29 +102,24 @@ jobs:
     vmImage: windows-latest
   timeoutInMinutes: 240
   steps:
-  - powershell: |
-      $urlbase = "https://dev.azure.com/git-for-windows/git/_apis/build/builds"
-      $id = ((Invoke-WebRequest -UseBasicParsing "${urlbase}?definitions=22&statusFilter=completed&resultFilter=succeeded&`$top=1").content | ConvertFrom-JSON).value[0].id
-      $downloadUrl = ((Invoke-WebRequest -UseBasicParsing "${urlbase}/$id/artifacts").content | ConvertFrom-JSON).value[1].resource.downloadUrl
-      (New-Object Net.WebClient).DownloadFile($downloadUrl,"git-sdk-64-minimal.zip")
-      Expand-Archive git-sdk-64-minimal.zip -DestinationPath . -Force
-      Remove-Item git-sdk-64-minimal.zip
-
+  - bash: git clone --bare --depth=1 --filter=blob:none --single-branch -b main https://github.com/git-for-windows/git-sdk-64
+    displayName: 'clone git-sdk-64'
+  - bash: git clone --depth=1 --single-branch -b main https://github.com/git-for-windows/build-extra
+    displayName: 'clone build-extra'
+  - bash: sh -x ./build-extra/please.sh create-sdk-artifact --sdk=git-sdk-64.git --out=git-sdk-64-minimal minimal-sdk
+    displayName: 'build git-sdk-64-minimal-sdk'
+  - bash: |
       # Let Git ignore the SDK and the test-cache
-      "/git-sdk-64-minimal/`n/test-cache/`n" | Out-File -NoNewLine -Encoding ascii -Append "$(Build.SourcesDirectory)\.git\info\exclude"
-    displayName: 'Download git-sdk-64-minimal'
-  - powershell: |
-      & git-sdk-64-minimal\usr\bin\bash.exe -lc @"
-        make NDEBUG=1 DEVELOPER=1 vcxproj
-      "@
-      if (!$?) { exit(1) }
+      printf "%s\n" /git-sdk-64-minimal/ /test-cache/ >>'.git/info/exclude'
+    displayName: 'Ignore untracked directories'
+  - bash: make NDEBUG=1 DEVELOPER=1 vcxproj
     displayName: Generate Visual Studio Solution
     env:
       HOME: $(Build.SourcesDirectory)
       MSYSTEM: MINGW64
       DEVELOPER: 1
       NO_PERL: 1
-      GIT_CONFIG_PARAMETERS: "'user.name=CI' 'user.email=ci@git'"
+      PATH: "$(Build.SourcesDirectory)\\git-sdk-64-minimal\\mingw64\\bin;$(Build.SourcesDirectory)\\git-sdk-64-minimal\\usr\\bin;C:\\Windows\\system32;C:\\Windows;C:\\Windows\\system32\\wbem"
   - powershell: |
       $urlbase = "https://dev.azure.com/git/git/_apis/build/builds"
       $id = ((Invoke-WebRequest -UseBasicParsing "${urlbase}?definitions=9&statusFilter=completed&resultFilter=succeeded&`$top=1").content | ConvertFrom-JSON).value[0].id
@@ -145,14 +135,10 @@ jobs:
       configuration: Release
       maximumCpuCount: 4
       msbuildArguments: /p:PlatformToolset=v142
-  - powershell: |
-      & compat\vcbuild\vcpkg_copy_dlls.bat release
-      if (!$?) { exit(1) }
-      & git-sdk-64-minimal\usr\bin\bash.exe -lc @"
-        mkdir -p artifacts &&
-        eval \"`$(make -n artifacts-tar INCLUDE_DLLS_IN_ARTIFACTS=YesPlease ARTIFACTS_DIRECTORY=artifacts | grep ^tar)\"
-      "@
-      if (!$?) { exit(1) }
+  - bash: |
+      ./compat/vcbuild/vcpkg_copy_dlls.bat release &&
+      mkdir -p artifacts &&
+      eval "$(make -n artifacts-tar INCLUDE_DLLS_IN_ARTIFACTS=YesPlease ARTIFACTS_DIRECTORY=artifacts | grep ^tar)"
     displayName: Bundle artifact tar
     env:
       HOME: $(Build.SourcesDirectory)
@@ -161,6 +147,7 @@ jobs:
       NO_PERL: 1
       MSVC: 1
       VCPKG_ROOT: $(Build.SourcesDirectory)\compat\vcbuild\vcpkg
+      PATH: "$(Build.SourcesDirectory)\\git-sdk-64-minimal\\mingw64\\bin;$(Build.SourcesDirectory)\\git-sdk-64-minimal\\usr\\bin;C:\\Windows\\system32;C:\\Windows;C:\\Windows\\system32\\wbem"
   - powershell: |
       $tag = (Invoke-WebRequest -UseBasicParsing "https://gitforwindows.org/latest-tag.txt").content
       $version = (Invoke-WebRequest -UseBasicParsing "https://gitforwindows.org/latest-version.txt").content
@@ -191,30 +178,28 @@ jobs:
     inputs:
       artifactName: 'vs-artifacts'
       targetPath: '$(Build.SourcesDirectory)'
-  - powershell: |
-      & PortableGit\git-cmd.exe --command=usr\bin\bash.exe -lc @"
-        test -f artifacts.tar.gz || {
-          echo No test artifacts found\; skipping >&2
-          exit 0
-        }
-        tar xf artifacts.tar.gz || exit 1
+  - bash: |
+      test -f artifacts.tar.gz || {
+        echo No test artifacts found\; skipping >&2
+        exit 0
+      }
+      tar xf artifacts.tar.gz || exit 1
 
-        # Let Git ignore the SDK and the test-cache
-        printf '%s\n' /PortableGit/ /test-cache/ >>.git/info/exclude
+      # Let Git ignore the SDK and the test-cache
+      printf '%s\n' /PortableGit/ /test-cache/ >>.git/info/exclude
 
-        cd t &&
-        PATH=\"`$PWD/helper:`$PATH\" &&
-        test-tool.exe run-command testsuite --jobs=10 -V -x --write-junit-xml \
-                `$(test-tool.exe path-utils slice-tests \
-                        `$SYSTEM_JOBPOSITIONINPHASE `$SYSTEM_TOTALJOBSINPHASE t[0-9]*.sh)
-      "@
-      if (!$?) { exit(1) }
+      cd t &&
+      PATH="$PWD/helper:$PATH" &&
+      test-tool.exe run-command testsuite --jobs=10 -V -x --write-junit-xml \
+              $(test-tool.exe path-utils slice-tests \
+                      $SYSTEM_JOBPOSITIONINPHASE $SYSTEM_TOTALJOBSINPHASE t[0-9]*.sh)
     displayName: 'Test (parallel)'
     env:
       HOME: $(Build.SourcesDirectory)
       MSYSTEM: MINGW64
       NO_SVN_TESTS: 1
       GIT_TEST_SKIP_REBASE_P: 1
+      PATH: "$(Build.SourcesDirectory)\\PortableGit\\mingw64\\bin;$(Build.SourcesDirectory)\\PortableGit\\usr\\bin;C:\\Windows\\system32;C:\\Windows;C:\\Windows\\system32\\wbem"
   - task: PublishTestResults@2
     displayName: 'Publish Test Results **/TEST-*.xml'
     inputs:

From fac524347ca5288e40af23ae6bcb5c82a7227366 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sun, 10 Jul 2022 00:52:40 +0200
Subject: [PATCH 112/259] azure-pipeline: downcase the job name of the
 `Linux32` job

These many refactorings in Git sure are gifts that keep on giving.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 azure-pipelines.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index f11f1342cd080b..21ee5a463380d6 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -339,13 +339,13 @@ jobs:
   steps:
   - bash: |
        res=0
-       sudo AGENT_OS="$AGENT_OS" BUILD_BUILDNUMBER="$BUILD_BUILDNUMBER" BUILD_REPOSITORY_URI="$BUILD_REPOSITORY_URI" BUILD_SOURCEBRANCH="$BUILD_SOURCEBRANCH" BUILD_SOURCEVERSION="$BUILD_SOURCEVERSION" SYSTEM_PHASENAME="$SYSTEM_PHASENAME" SYSTEM_TASKDEFINITIONSURI="$SYSTEM_TASKDEFINITIONSURI" SYSTEM_TEAMPROJECT="$SYSTEM_TEAMPROJECT" CC=$CC MAKEFLAGS="$MAKEFLAGS" jobname=Linux32 bash -lxc ci/run-docker.sh || res=1
+       sudo AGENT_OS="$AGENT_OS" BUILD_BUILDNUMBER="$BUILD_BUILDNUMBER" BUILD_REPOSITORY_URI="$BUILD_REPOSITORY_URI" BUILD_SOURCEBRANCH="$BUILD_SOURCEBRANCH" BUILD_SOURCEVERSION="$BUILD_SOURCEVERSION" SYSTEM_PHASENAME="$SYSTEM_PHASENAME" SYSTEM_TASKDEFINITIONSURI="$SYSTEM_TASKDEFINITIONSURI" SYSTEM_TEAMPROJECT="$SYSTEM_TEAMPROJECT" CC=$CC MAKEFLAGS="$MAKEFLAGS" jobname=linux32 bash -lxc ci/run-docker.sh || res=1
 
        sudo chmod a+r t/out/TEST-*.xml
        test ! -d t/failed-test-artifacts || sudo chmod a+r t/failed-test-artifacts
 
        exit $res
-    displayName: 'jobname=Linux32 ci/run-docker.sh'
+    displayName: 'jobname=linux32 ci/run-docker.sh'
   - task: PublishTestResults@2
     displayName: 'Publish Test Results **/TEST-*.xml'
     inputs:

From d6c73a5a186a050df3b662f71ae48b6659a85cf0 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 4 Sep 2017 11:59:45 +0200
Subject: [PATCH 113/259] mingw: change core.fsyncObjectFiles = 1 by default
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From the documentation of said setting:

	This boolean will enable fsync() when writing object files.

	This is a total waste of time and effort on a filesystem that
	orders data writes properly, but can be useful for filesystems
	that do not use journalling (traditional UNIX filesystems) or
	that only journal metadata and not file contents (OS X’s HFS+,
	or Linux ext3 with "data=writeback").

The most common file system on Windows (NTFS) does not guarantee that
order, therefore a sudden loss of power (or any other event causing an
unclean shutdown) would cause corrupt files (i.e. files filled with
NULs). Therefore we need to change the default.

Note that the documentation makes it sound as if this causes really bad
performance. In reality, writing loose objects is something that is done
only rarely, and only a handful of files at a time.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compat/mingw.c b/compat/mingw.c
index d9477f9e5a4e64..47efa7008c227b 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -19,6 +19,7 @@
 #include "gettext.h"
 #define SECURITY_WIN32
 #include <sspi.h>
+#include "../write-or-die.h"
 #include "../repository.h"
 
 #define HCAST(type, handle) ((type)(intptr_t)handle)
@@ -3130,6 +3131,7 @@ int wmain(int argc, const wchar_t **wargv)
 #endif
 
 	maybe_redirect_std_handles();
+	fsync_object_files = 1;
 
 	/* determine size of argv and environ conversion buffer */
 	maxlen = wcslen(wargv[0]);

From dd17e899501f97bfb03b2e205a3c58fb141384bb Mon Sep 17 00:00:00 2001
From: Taylor Blau <me@ttaylorr.com>
Date: Mon, 8 Feb 2021 16:22:34 -0500
Subject: [PATCH 114/259] azure-pipeline: run static-analysis on jammy

This is inspired by d051ed77ee6 (.github/workflows/main.yml: run
static-analysis on bionic, 2021-02-08) and by ef46584831 (ci: update
'static-analysis' to Ubuntu 22.04, 2022-08-23), adapted to the Azure
Pipeline.

When Azure Pipelines' build agents transitioned 'ubuntu-latest' from
18.04 to 20.04, it broke our `static-analysis` job, since Coccinelle
was not madeavailable on Ubuntu focal (it is only available in the
universe suite).

This is not an issue with Ubuntu 22.04, but we will only know whether it
is an issue with 24.04 when _that_ comes out. So let's play it safe and
pin the `static_analysis` job to the latest Ubuntu version that we know
to offer a working Coccinelle package.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 azure-pipelines.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index 21ee5a463380d6..fed26341d49a4a 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -365,7 +365,7 @@ jobs:
   displayName: StaticAnalysis
   condition: succeeded()
   pool:
-    vmImage: ubuntu-latest
+    vmImage: ubuntu-22.04
   steps:
   - bash: |
        sudo apt-get update &&

From 6f296a1a850e1d5e5d6a8009d9d4d93f55d3aa97 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sat, 6 May 2023 22:26:15 +0200
Subject: [PATCH 115/259] http: optionally load libcurl lazily

This compile-time option allows to ask Git to load libcurl dynamically
at runtime.

Together with a follow-up patch that optionally overrides the file name
depending on the `http.sslBackend` setting, this kicks open the door for
installing multiple libcurl flavors side by side, and load the one
corresponding to the (runtime-)configured SSL/TLS backend.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 Makefile               |  28 +++-
 compat/lazyload-curl.c | 354 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 375 insertions(+), 7 deletions(-)
 create mode 100644 compat/lazyload-curl.c

diff --git a/Makefile b/Makefile
index d6479092a0b8df..61212a3ed25618 100644
--- a/Makefile
+++ b/Makefile
@@ -467,6 +467,11 @@ include shared.mak
 #
 #     CURL_LDFLAGS=-lcurl
 #
+# Define LAZYLOAD_LIBCURL to dynamically load the libcurl; This can be useful
+# if Multiple libcurl versions exist (with different file names) that link to
+# various SSL/TLS backends, to support the `http.sslBackend` runtime switch in
+# such a scenario.
+#
 # === Optional library: libpcre2 ===
 #
 # Define USE_LIBPCRE if you have and want to use libpcre. Various
@@ -1616,10 +1621,19 @@ else
 		CURL_LIBCURL =
         endif
 
-        ifndef CURL_LDFLAGS
-		CURL_LDFLAGS = $(eval CURL_LDFLAGS := $$(shell $$(CURL_CONFIG) --libs))$(CURL_LDFLAGS)
+        ifdef LAZYLOAD_LIBCURL
+		LAZYLOAD_LIBCURL_OBJ = compat/lazyload-curl.o
+		OBJECTS += $(LAZYLOAD_LIBCURL_OBJ)
+		# The `CURL_STATICLIB` constant must be defined to avoid seeing the functions
+		# declared as DLL imports
+		CURL_CFLAGS = -DCURL_STATICLIB
+		CURL_LIBCURL = -ldl
+        else
+                ifndef CURL_LDFLAGS
+			CURL_LDFLAGS = $(eval CURL_LDFLAGS := $$(shell $$(CURL_CONFIG) --libs))$(CURL_LDFLAGS)
+                endif
+		CURL_LIBCURL += $(CURL_LDFLAGS)
         endif
-	CURL_LIBCURL += $(CURL_LDFLAGS)
 
         ifndef CURL_CFLAGS
 		CURL_CFLAGS = $(eval CURL_CFLAGS := $$(shell $$(CURL_CONFIG) --cflags))$(CURL_CFLAGS)
@@ -1640,7 +1654,7 @@ else
         endif
         ifdef USE_CURL_FOR_IMAP_SEND
 		BASIC_CFLAGS += -DUSE_CURL_FOR_IMAP_SEND
-		IMAP_SEND_BUILDDEPS = http.o
+		IMAP_SEND_BUILDDEPS = http.o $(LAZYLOAD_LIBCURL_OBJ)
 		IMAP_SEND_LDFLAGS += $(CURL_LIBCURL)
         endif
         ifndef NO_EXPAT
@@ -2831,10 +2845,10 @@ git-imap-send$X: imap-send.o $(IMAP_SEND_BUILDDEPS) GIT-LDFLAGS $(GITLIBS)
 	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
 		$(IMAP_SEND_LDFLAGS) $(LIBS)
 
-git-http-fetch$X: http.o http-walker.o http-fetch.o GIT-LDFLAGS $(GITLIBS)
+git-http-fetch$X: http.o http-walker.o http-fetch.o $(LAZYLOAD_LIBCURL_OBJ) GIT-LDFLAGS $(GITLIBS)
 	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
 		$(CURL_LIBCURL) $(LIBS)
-git-http-push$X: http.o http-push.o GIT-LDFLAGS $(GITLIBS)
+git-http-push$X: http.o http-push.o $(LAZYLOAD_LIBCURL_OBJ) GIT-LDFLAGS $(GITLIBS)
 	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
 		$(CURL_LIBCURL) $(EXPAT_LIBEXPAT) $(LIBS)
 
@@ -2844,7 +2858,7 @@ $(REMOTE_CURL_ALIASES): $(REMOTE_CURL_PRIMARY)
 	ln -s $< $@ 2>/dev/null || \
 	cp $< $@
 
-$(REMOTE_CURL_PRIMARY): remote-curl.o http.o http-walker.o GIT-LDFLAGS $(GITLIBS)
+$(REMOTE_CURL_PRIMARY): remote-curl.o http.o http-walker.o $(LAZYLOAD_LIBCURL_OBJ) GIT-LDFLAGS $(GITLIBS)
 	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
 		$(CURL_LIBCURL) $(EXPAT_LIBEXPAT) $(LIBS)
 
diff --git a/compat/lazyload-curl.c b/compat/lazyload-curl.c
new file mode 100644
index 00000000000000..19aa2b6d4b6942
--- /dev/null
+++ b/compat/lazyload-curl.c
@@ -0,0 +1,354 @@
+#include "../git-compat-util.h"
+#include "../git-curl-compat.h"
+#include <dlfcn.h>
+
+/*
+ * The ABI version of libcurl is encoded in its shared libraries' file names.
+ * This ABI version has not changed since October 2006 and is unlikely to be
+ * changed in the future. See https://curl.se/libcurl/abi.html for details.
+ */
+#define LIBCURL_ABI_VERSION "4"
+
+typedef void (*func_t)(void);
+
+#ifdef __APPLE__
+#define LIBCURL_FILE_NAME(base) base "." LIBCURL_ABI_VERSION ".dylib"
+#else
+#define LIBCURL_FILE_NAME(base) base ".so." LIBCURL_ABI_VERSION
+#endif
+
+static void *load_library(const char *name)
+{
+	return dlopen(name, RTLD_LAZY);
+}
+
+static func_t load_function(void *handle, const char *name)
+{
+	/*
+	 * Casting the return value of `dlsym()` to a function pointer is
+	 * explicitly allowed in recent POSIX standards, but GCC complains
+	 * about this in pedantic mode nevertheless. For more about this issue,
+	 * see https://stackoverflow.com/q/31526876/1860823 and
+	 * http://stackoverflow.com/a/36385690/1905491.
+	 */
+	func_t f;
+	*(void **)&f = dlsym(handle, name);
+	return f;
+}
+
+typedef struct curl_version_info_data *(*curl_version_info_type)(CURLversion version);
+static curl_version_info_type curl_version_info_func;
+
+typedef char *(*curl_easy_escape_type)(CURL *handle, const char *string, int length);
+static curl_easy_escape_type curl_easy_escape_func;
+
+typedef void (*curl_free_type)(void *p);
+static curl_free_type curl_free_func;
+
+typedef CURLcode (*curl_global_init_type)(long flags);
+static curl_global_init_type curl_global_init_func;
+
+typedef CURLsslset (*curl_global_sslset_type)(curl_sslbackend id, const char *name, const curl_ssl_backend ***avail);
+static curl_global_sslset_type curl_global_sslset_func;
+
+typedef void (*curl_global_cleanup_type)(void);
+static curl_global_cleanup_type curl_global_cleanup_func;
+
+typedef struct curl_slist *(*curl_slist_append_type)(struct curl_slist *list, const char *data);
+static curl_slist_append_type curl_slist_append_func;
+
+typedef void (*curl_slist_free_all_type)(struct curl_slist *list);
+static curl_slist_free_all_type curl_slist_free_all_func;
+
+typedef const char *(*curl_easy_strerror_type)(CURLcode error);
+static curl_easy_strerror_type curl_easy_strerror_func;
+
+typedef CURLM *(*curl_multi_init_type)(void);
+static curl_multi_init_type curl_multi_init_func;
+
+typedef CURLMcode (*curl_multi_add_handle_type)(CURLM *multi_handle, CURL *curl_handle);
+static curl_multi_add_handle_type curl_multi_add_handle_func;
+
+typedef CURLMcode (*curl_multi_remove_handle_type)(CURLM *multi_handle, CURL *curl_handle);
+static curl_multi_remove_handle_type curl_multi_remove_handle_func;
+
+typedef CURLMcode (*curl_multi_fdset_type)(CURLM *multi_handle, fd_set *read_fd_set, fd_set *write_fd_set, fd_set *exc_fd_set, int *max_fd);
+static curl_multi_fdset_type curl_multi_fdset_func;
+
+typedef CURLMcode (*curl_multi_perform_type)(CURLM *multi_handle, int *running_handles);
+static curl_multi_perform_type curl_multi_perform_func;
+
+typedef CURLMcode (*curl_multi_cleanup_type)(CURLM *multi_handle);
+static curl_multi_cleanup_type curl_multi_cleanup_func;
+
+typedef CURLMsg *(*curl_multi_info_read_type)(CURLM *multi_handle, int *msgs_in_queue);
+static curl_multi_info_read_type curl_multi_info_read_func;
+
+typedef const char *(*curl_multi_strerror_type)(CURLMcode error);
+static curl_multi_strerror_type curl_multi_strerror_func;
+
+typedef CURLMcode (*curl_multi_timeout_type)(CURLM *multi_handle, long *milliseconds);
+static curl_multi_timeout_type curl_multi_timeout_func;
+
+typedef CURL *(*curl_easy_init_type)(void);
+static curl_easy_init_type curl_easy_init_func;
+
+typedef CURLcode (*curl_easy_perform_type)(CURL *curl);
+static curl_easy_perform_type curl_easy_perform_func;
+
+typedef void (*curl_easy_cleanup_type)(CURL *curl);
+static curl_easy_cleanup_type curl_easy_cleanup_func;
+
+typedef CURL *(*curl_easy_duphandle_type)(CURL *curl);
+static curl_easy_duphandle_type curl_easy_duphandle_func;
+
+typedef CURLcode (*curl_easy_getinfo_long_type)(CURL *curl, CURLINFO info, long *value);
+static curl_easy_getinfo_long_type curl_easy_getinfo_long_func;
+
+typedef CURLcode (*curl_easy_getinfo_pointer_type)(CURL *curl, CURLINFO info, void **value);
+static curl_easy_getinfo_pointer_type curl_easy_getinfo_pointer_func;
+
+typedef CURLcode (*curl_easy_getinfo_off_t_type)(CURL *curl, CURLINFO info, curl_off_t *value);
+static curl_easy_getinfo_off_t_type curl_easy_getinfo_off_t_func;
+
+typedef CURLcode (*curl_easy_setopt_long_type)(CURL *curl, CURLoption opt, long value);
+static curl_easy_setopt_long_type curl_easy_setopt_long_func;
+
+typedef CURLcode (*curl_easy_setopt_pointer_type)(CURL *curl, CURLoption opt, void *value);
+static curl_easy_setopt_pointer_type curl_easy_setopt_pointer_func;
+
+typedef CURLcode (*curl_easy_setopt_off_t_type)(CURL *curl, CURLoption opt, curl_off_t value);
+static curl_easy_setopt_off_t_type curl_easy_setopt_off_t_func;
+
+static void lazy_load_curl(void)
+{
+	static int initialized;
+	void *libcurl;
+	func_t curl_easy_getinfo_func, curl_easy_setopt_func;
+
+	if (initialized)
+		return;
+
+	initialized = 1;
+	libcurl = load_library(LIBCURL_FILE_NAME("libcurl"));
+	if (!libcurl)
+		die("failed to load library '%s'", LIBCURL_FILE_NAME("libcurl"));
+
+	curl_version_info_func = (curl_version_info_type)load_function(libcurl, "curl_version_info");
+	curl_easy_escape_func = (curl_easy_escape_type)load_function(libcurl, "curl_easy_escape");
+	curl_free_func = (curl_free_type)load_function(libcurl, "curl_free");
+	curl_global_init_func = (curl_global_init_type)load_function(libcurl, "curl_global_init");
+	curl_global_sslset_func = (curl_global_sslset_type)load_function(libcurl, "curl_global_sslset");
+	curl_global_cleanup_func = (curl_global_cleanup_type)load_function(libcurl, "curl_global_cleanup");
+	curl_slist_append_func = (curl_slist_append_type)load_function(libcurl, "curl_slist_append");
+	curl_slist_free_all_func = (curl_slist_free_all_type)load_function(libcurl, "curl_slist_free_all");
+	curl_easy_strerror_func = (curl_easy_strerror_type)load_function(libcurl, "curl_easy_strerror");
+	curl_multi_init_func = (curl_multi_init_type)load_function(libcurl, "curl_multi_init");
+	curl_multi_add_handle_func = (curl_multi_add_handle_type)load_function(libcurl, "curl_multi_add_handle");
+	curl_multi_remove_handle_func = (curl_multi_remove_handle_type)load_function(libcurl, "curl_multi_remove_handle");
+	curl_multi_fdset_func = (curl_multi_fdset_type)load_function(libcurl, "curl_multi_fdset");
+	curl_multi_perform_func = (curl_multi_perform_type)load_function(libcurl, "curl_multi_perform");
+	curl_multi_cleanup_func = (curl_multi_cleanup_type)load_function(libcurl, "curl_multi_cleanup");
+	curl_multi_info_read_func = (curl_multi_info_read_type)load_function(libcurl, "curl_multi_info_read");
+	curl_multi_strerror_func = (curl_multi_strerror_type)load_function(libcurl, "curl_multi_strerror");
+	curl_multi_timeout_func = (curl_multi_timeout_type)load_function(libcurl, "curl_multi_timeout");
+	curl_easy_init_func = (curl_easy_init_type)load_function(libcurl, "curl_easy_init");
+	curl_easy_perform_func = (curl_easy_perform_type)load_function(libcurl, "curl_easy_perform");
+	curl_easy_cleanup_func = (curl_easy_cleanup_type)load_function(libcurl, "curl_easy_cleanup");
+	curl_easy_duphandle_func = (curl_easy_duphandle_type)load_function(libcurl, "curl_easy_duphandle");
+
+	curl_easy_getinfo_func = load_function(libcurl, "curl_easy_getinfo");
+	curl_easy_getinfo_long_func = (curl_easy_getinfo_long_type)curl_easy_getinfo_func;
+	curl_easy_getinfo_pointer_func = (curl_easy_getinfo_pointer_type)curl_easy_getinfo_func;
+	curl_easy_getinfo_off_t_func = (curl_easy_getinfo_off_t_type)curl_easy_getinfo_func;
+
+	curl_easy_setopt_func = load_function(libcurl, "curl_easy_setopt");
+	curl_easy_setopt_long_func = (curl_easy_setopt_long_type)curl_easy_setopt_func;
+	curl_easy_setopt_pointer_func = (curl_easy_setopt_pointer_type)curl_easy_setopt_func;
+	curl_easy_setopt_off_t_func = (curl_easy_setopt_off_t_type)curl_easy_setopt_func;
+}
+
+struct curl_version_info_data *curl_version_info(CURLversion version)
+{
+	lazy_load_curl();
+	return curl_version_info_func(version);
+}
+
+char *curl_easy_escape(CURL *handle, const char *string, int length)
+{
+	lazy_load_curl();
+	return curl_easy_escape_func(handle, string, length);
+}
+
+void curl_free(void *p)
+{
+	lazy_load_curl();
+	curl_free_func(p);
+}
+
+CURLcode curl_global_init(long flags)
+{
+	lazy_load_curl();
+	return curl_global_init_func(flags);
+}
+
+CURLsslset curl_global_sslset(curl_sslbackend id, const char *name, const curl_ssl_backend ***avail)
+{
+	lazy_load_curl();
+	return curl_global_sslset_func(id, name, avail);
+}
+
+void curl_global_cleanup(void)
+{
+	lazy_load_curl();
+	curl_global_cleanup_func();
+}
+
+struct curl_slist *curl_slist_append(struct curl_slist *list, const char *data)
+{
+	lazy_load_curl();
+	return curl_slist_append_func(list, data);
+}
+
+void curl_slist_free_all(struct curl_slist *list)
+{
+	lazy_load_curl();
+	curl_slist_free_all_func(list);
+}
+
+const char *curl_easy_strerror(CURLcode error)
+{
+	lazy_load_curl();
+	return curl_easy_strerror_func(error);
+}
+
+CURLM *curl_multi_init(void)
+{
+	lazy_load_curl();
+	return curl_multi_init_func();
+}
+
+CURLMcode curl_multi_add_handle(CURLM *multi_handle, CURL *curl_handle)
+{
+	lazy_load_curl();
+	return curl_multi_add_handle_func(multi_handle, curl_handle);
+}
+
+CURLMcode curl_multi_remove_handle(CURLM *multi_handle, CURL *curl_handle)
+{
+	lazy_load_curl();
+	return curl_multi_remove_handle_func(multi_handle, curl_handle);
+}
+
+CURLMcode curl_multi_fdset(CURLM *multi_handle, fd_set *read_fd_set, fd_set *write_fd_set, fd_set *exc_fd_set, int *max_fd)
+{
+	lazy_load_curl();
+	return curl_multi_fdset_func(multi_handle, read_fd_set, write_fd_set, exc_fd_set, max_fd);
+}
+
+CURLMcode curl_multi_perform(CURLM *multi_handle, int *running_handles)
+{
+	lazy_load_curl();
+	return curl_multi_perform_func(multi_handle, running_handles);
+}
+
+CURLMcode curl_multi_cleanup(CURLM *multi_handle)
+{
+	lazy_load_curl();
+	return curl_multi_cleanup_func(multi_handle);
+}
+
+CURLMsg *curl_multi_info_read(CURLM *multi_handle, int *msgs_in_queue)
+{
+	lazy_load_curl();
+	return curl_multi_info_read_func(multi_handle, msgs_in_queue);
+}
+
+const char *curl_multi_strerror(CURLMcode error)
+{
+	lazy_load_curl();
+	return curl_multi_strerror_func(error);
+}
+
+CURLMcode curl_multi_timeout(CURLM *multi_handle, long *milliseconds)
+{
+	lazy_load_curl();
+	return curl_multi_timeout_func(multi_handle, milliseconds);
+}
+
+CURL *curl_easy_init(void)
+{
+	lazy_load_curl();
+	return curl_easy_init_func();
+}
+
+CURLcode curl_easy_perform(CURL *curl)
+{
+	lazy_load_curl();
+	return curl_easy_perform_func(curl);
+}
+
+void curl_easy_cleanup(CURL *curl)
+{
+	lazy_load_curl();
+	curl_easy_cleanup_func(curl);
+}
+
+CURL *curl_easy_duphandle(CURL *curl)
+{
+	lazy_load_curl();
+	return curl_easy_duphandle_func(curl);
+}
+
+#ifndef CURL_IGNORE_DEPRECATION
+#define CURL_IGNORE_DEPRECATION(x) x
+#endif
+
+#ifndef CURLOPTTYPE_BLOB
+#define CURLOPTTYPE_BLOB 40000
+#endif
+
+#undef curl_easy_getinfo
+CURLcode curl_easy_getinfo(CURL *curl, CURLINFO info, ...)
+{
+	va_list ap;
+	CURLcode res;
+
+	va_start(ap, info);
+	lazy_load_curl();
+	CURL_IGNORE_DEPRECATION(
+		if (info >= CURLINFO_LONG && info < CURLINFO_DOUBLE)
+			res = curl_easy_getinfo_long_func(curl, info, va_arg(ap, long *));
+		else if ((info >= CURLINFO_STRING && info < CURLINFO_LONG) ||
+			 (info >= CURLINFO_SLIST && info < CURLINFO_SOCKET))
+			res = curl_easy_getinfo_pointer_func(curl, info, va_arg(ap, void **));
+		else if (info >= CURLINFO_OFF_T)
+			res = curl_easy_getinfo_off_t_func(curl, info, va_arg(ap, curl_off_t *));
+		else
+			die("%s:%d: TODO (info: %d)!", __FILE__, __LINE__, info);
+	)
+	va_end(ap);
+	return res;
+}
+
+#undef curl_easy_setopt
+CURLcode curl_easy_setopt(CURL *curl, CURLoption opt, ...)
+{
+	va_list ap;
+	CURLcode res;
+
+	va_start(ap, opt);
+	lazy_load_curl();
+	CURL_IGNORE_DEPRECATION(
+		if (opt >= CURLOPTTYPE_LONG && opt < CURLOPTTYPE_OBJECTPOINT)
+			res = curl_easy_setopt_long_func(curl, opt, va_arg(ap, long));
+		else if (opt >= CURLOPTTYPE_OBJECTPOINT && opt < CURLOPTTYPE_OFF_T)
+			res = curl_easy_setopt_pointer_func(curl, opt, va_arg(ap, void *));
+		else if (opt >= CURLOPTTYPE_OFF_T && opt < CURLOPTTYPE_BLOB)
+			res = curl_easy_setopt_off_t_func(curl, opt, va_arg(ap, curl_off_t));
+		else
+			die("%s:%d: TODO (opt: %d)!", __FILE__, __LINE__, opt);
+	)
+	va_end(ap);
+	return res;
+}

From c8feee1d43ba0413d517443ed54ea59e1b8371ed Mon Sep 17 00:00:00 2001
From: Dennis Ameling <dennis@dennisameling.com>
Date: Tue, 4 Oct 2022 09:59:32 +0200
Subject: [PATCH 116/259] config.mak.uname: add support for clangarm64

CLANGARM64 is a relatively new MSYSTEM added by the MSYS2 team. In order
to have Git build correctly for this platform, let's add some
configuration for it to config.mak.uname.

Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
---
 config.mak.uname | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/config.mak.uname b/config.mak.uname
index bbf7744ddd5d0f..bf7366cd4ddf8f 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -724,6 +724,10 @@ ifeq ($(uname_S),MINGW)
 		prefix = /mingw64
 		HOST_CPU = x86_64
 		BASIC_LDFLAGS += -Wl,--pic-executable,-e,mainCRTStartup
+        else ifeq (CLANGARM64,$(MSYSTEM))
+		prefix = /clangarm64
+		HOST_CPU = aarch64
+		BASIC_LDFLAGS += -Wl,--pic-executable,-e,mainCRTStartup
         else
 		COMPAT_CFLAGS += -D_USE_32BIT_TIME_T
 		BASIC_LDFLAGS += -Wl,--large-address-aware

From 7015b7e27c67c7626fe9dafad27bd2a5ad4004c9 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sun, 7 May 2023 22:51:52 +0200
Subject: [PATCH 117/259] http: support lazy-loading libcurl also on Windows

This implements the Windows-specific support code, because everything is
slightly different on Windows, even loading shared libraries.

Note: I specifically do _not_ use the code from
`compat/win32/lazyload.h` here because that code is optimized for
loading individual functions from various system DLLs, while we
specifically want to load _many_ functions from _one_ DLL here, and
distinctly not a system DLL (we expect libcurl to be located outside
`C:\Windows\system32`, something `INIT_PROC_ADDR` refuses to work with).
Also, the `curl_easy_getinfo()`/`curl_easy_setopt()` functions are
declared as vararg functions, which `lazyload.h` cannot handle. Finally,
we are about to optionally override the exact file name that is to be
loaded, which is a goal contrary to `lazyload.h`'s design.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 Makefile               |  4 ++++
 compat/lazyload-curl.c | 52 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 56 insertions(+)

diff --git a/Makefile b/Makefile
index 61212a3ed25618..ee583473708a05 100644
--- a/Makefile
+++ b/Makefile
@@ -1627,7 +1627,11 @@ else
 		# The `CURL_STATICLIB` constant must be defined to avoid seeing the functions
 		# declared as DLL imports
 		CURL_CFLAGS = -DCURL_STATICLIB
+ifneq ($(uname_S),MINGW)
+ifneq ($(uname_S),Windows)
 		CURL_LIBCURL = -ldl
+endif
+endif
         else
                 ifndef CURL_LDFLAGS
 			CURL_LDFLAGS = $(eval CURL_LDFLAGS := $$(shell $$(CURL_CONFIG) --libs))$(CURL_LDFLAGS)
diff --git a/compat/lazyload-curl.c b/compat/lazyload-curl.c
index 19aa2b6d4b6942..98d73fb0f2a66f 100644
--- a/compat/lazyload-curl.c
+++ b/compat/lazyload-curl.c
@@ -1,6 +1,8 @@
 #include "../git-compat-util.h"
 #include "../git-curl-compat.h"
+#ifndef WIN32
 #include <dlfcn.h>
+#endif
 
 /*
  * The ABI version of libcurl is encoded in its shared libraries' file names.
@@ -11,6 +13,7 @@
 
 typedef void (*func_t)(void);
 
+#ifndef WIN32
 #ifdef __APPLE__
 #define LIBCURL_FILE_NAME(base) base "." LIBCURL_ABI_VERSION ".dylib"
 #else
@@ -35,6 +38,55 @@ static func_t load_function(void *handle, const char *name)
 	*(void **)&f = dlsym(handle, name);
 	return f;
 }
+#else
+#define LIBCURL_FILE_NAME(base) base "-" LIBCURL_ABI_VERSION ".dll"
+
+static void *load_library(const char *name)
+{
+	size_t name_size = strlen(name) + 1;
+	const char *path = getenv("PATH");
+	char dll_path[MAX_PATH];
+
+	while (path && *path) {
+		const char *sep = strchrnul(path, ';');
+		size_t len = sep - path;
+
+		if (len && len + name_size < sizeof(dll_path)) {
+			memcpy(dll_path, path, len);
+			dll_path[len] = '/';
+			memcpy(dll_path + len + 1, name, name_size);
+
+			if (!access(dll_path, R_OK)) {
+				wchar_t wpath[MAX_PATH];
+				int wlen = MultiByteToWideChar(CP_UTF8, 0, dll_path, -1, wpath, ARRAY_SIZE(wpath));
+				void *res = wlen ? (void *)LoadLibraryExW(wpath, NULL, 0) : NULL;
+				if (!res) {
+					DWORD err = GetLastError();
+					char buf[1024];
+
+					if (!FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM |
+							    FORMAT_MESSAGE_ARGUMENT_ARRAY |
+							    FORMAT_MESSAGE_IGNORE_INSERTS,
+							    NULL, err, LANG_NEUTRAL,
+							    buf, sizeof(buf) - 1, NULL))
+						xsnprintf(buf, sizeof(buf), "last error: %ld", err);
+					error("LoadLibraryExW() failed with: %s", buf);
+				}
+				return res;
+			}
+		}
+
+		path = *sep ? sep + 1 : NULL;
+	}
+
+	return NULL;
+}
+
+static func_t load_function(void *handle, const char *name)
+{
+	return (func_t)GetProcAddress((HANDLE)handle, name);
+}
+#endif
 
 typedef struct curl_version_info_data *(*curl_version_info_type)(CURLversion version);
 static curl_version_info_type curl_version_info_func;

From b528f184b3df1cb9dff1e8abdbab4a2021e8de31 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Matthias=20A=C3=9Fhauer?= <mha1993@live.de>
Date: Sun, 10 Jul 2022 11:27:25 +0200
Subject: [PATCH 118/259] MinGW: link as terminal server aware
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Whith Windows 2000, Microsoft introduced a flag to the PE header to mark executables as
"terminal server aware". Windows terminal servers provide a redirected Windows directory and
redirected registry hives when launching legacy applications without this flag set. Since we
do not use any INI files in the Windows directory and don't write to the registry, we don't
need  this additional preparation. Telling the OS that we don't need this should provide
slightly improved startup times in terminal server environments.

When building for supported Windows Versions with MSVC the /TSAWARE linker flag is
automatically set, but MinGW requires us to set the --tsaware flag manually.

This partially addresses https://github.com/git-for-windows/git/issues/3935.

Signed-off-by: Matthias Aßhauer <mha1993@live.de>
---
 config.mak.uname | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/config.mak.uname b/config.mak.uname
index bbf7744ddd5d0f..33e75a076d715b 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -691,7 +691,7 @@ ifeq ($(uname_S),MINGW)
 	DEFAULT_HELP_FORMAT = html
 	HAVE_PLATFORM_PROCINFO = YesPlease
 	CSPRNG_METHOD = rtlgenrandom
-	BASIC_LDFLAGS += -municode
+	BASIC_LDFLAGS += -municode -Wl,--tsaware
 	COMPAT_CFLAGS += -DNOGDI -Icompat -Icompat/win32
 	COMPAT_CFLAGS += -DSTRIP_EXTENSION=\".exe\"
 	COMPAT_OBJS += compat/mingw.o compat/winansi.o \

From 7be890e9b0c3dfc53c75e8d9ff80b45d05f4175f Mon Sep 17 00:00:00 2001
From: Kiel Hurley <kielhurley@gmail.com>
Date: Wed, 2 Nov 2022 22:56:16 +1300
Subject: [PATCH 119/259] Fix Windows version resources

Add FileVersion, which is a required field
As not all required fields were present, none were being included
Fixes #4090

Signed-off-by: Kiel Hurley <kielhurley@gmail.com>
---
 git.rc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/git.rc b/git.rc
index cc3fdc6cc6cb83..9c08cb214ac4a9 100644
--- a/git.rc
+++ b/git.rc
@@ -12,6 +12,7 @@ BEGIN
       VALUE "OriginalFilename", "git.exe\0"
       VALUE "ProductName", "Git\0"
       VALUE "ProductVersion", GIT_VERSION "\0"
+      VALUE "FileVersion", GIT_VERSION "\0"
     END
   END
 

From f28be8b8b81980a1b120bcd1ecd3fd3afc26f8c3 Mon Sep 17 00:00:00 2001
From: Dennis Ameling <dennis@dennisameling.com>
Date: Tue, 4 Oct 2022 09:58:10 +0200
Subject: [PATCH 120/259] bswap.h: add support for built-in bswap functions

Newer compiler versions, like GCC 10 and Clang 12, have built-in
functions for bswap32 and bswap64. This comes in handy, for example,
when targeting CLANGARM64 on Windows, which would not be supported
without this logic.

Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
---
 compat/bswap.h | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/compat/bswap.h b/compat/bswap.h
index 512f6f4b9937c8..a443e99eef2f1c 100644
--- a/compat/bswap.h
+++ b/compat/bswap.h
@@ -35,7 +35,19 @@ static inline uint64_t default_bswap64(uint64_t val)
 #undef bswap32
 #undef bswap64
 
-#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
+/**
+ * __has_builtin is available since Clang 10 and GCC 10.
+ * Below is a fallback for older compilers.
+ */
+#ifndef __has_builtin
+	#define __has_builtin(x) 0
+#endif
+
+#if __has_builtin(__builtin_bswap32) && __has_builtin(__builtin_bswap64)
+#define bswap32(x) __builtin_bswap32((x))
+#define bswap64(x) __builtin_bswap64((x))
+
+#elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
 
 #define bswap32 git_bswap32
 static inline uint32_t git_bswap32(uint32_t x)

From 1dd84d1808bbc6139a5ec3749b3ceba3a3afa21c Mon Sep 17 00:00:00 2001
From: Dennis Ameling <dennis@dennisameling.com>
Date: Tue, 4 Oct 2022 10:09:10 +0200
Subject: [PATCH 121/259] ci: create clangarm64-build.yml

No GitHub-hosted ARM64 runners are available at the moment of writing,
but folks can leverage self-hosted runners of this architecture. This CI
pipeline comes in handy for forks of the git-for-windows/git project
that have such runners available. The pipeline can be kicked off
manually through a workflow_dispatch.

Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
---
 .github/workflows/clangarm64-build.yml | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)
 create mode 100644 .github/workflows/clangarm64-build.yml

diff --git a/.github/workflows/clangarm64-build.yml b/.github/workflows/clangarm64-build.yml
new file mode 100644
index 00000000000000..79d1c7589d8033
--- /dev/null
+++ b/.github/workflows/clangarm64-build.yml
@@ -0,0 +1,25 @@
+name: CLANG build ARM64
+
+on:
+  workflow_dispatch:
+
+defaults:
+  run:
+    shell: bash
+
+jobs:
+  clang-build:
+    runs-on: [Windows, ARM64]
+    env:
+      NO_PERL: 1
+    steps:
+      - uses: actions/checkout@v4
+      - uses: git-for-windows/setup-git-for-windows-sdk@v1
+        with:
+          flavor: makepkg-git
+          architecture: aarch64
+          # This assumes that the job is running on a self-hosted runner,
+          # in which case we need to cleanup SDK files.
+          cleanup: true
+      - name: Build Git CLANGARM64
+        run: make -j`nproc`

From 521b0e091f8464c6d68efad8034bb0591c37c57e Mon Sep 17 00:00:00 2001
From: Andrey Zabavnikov <zabavnikov@gmail.com>
Date: Fri, 28 Oct 2022 17:12:06 +0300
Subject: [PATCH 122/259] status: fix for old-style submodules with commondir

In f9b7573f6b00 (repository: free fields before overwriting them,
2017-09-05), Git was taught to release memory before overwriting it, but
357a03ebe9e0 (repository.c: move env-related setup code back to
environment.c, 2018-03-03) changed the code so that it would not
_always_ be overwritten.

As a consequence, the `commondir` attribute would point to
already-free()d memory.

This seems not to cause problems in core Git, but there are add-on
patches in Git for Windows where the `commondir` attribute is
subsequently used and causing invalid memory accesses e.g. in setups
containing old-style submodules (i.e. the ones with a `.git` directory
within theirs worktrees) that have `commondir` configured.

This fixes https://github.com/git-for-windows/git/pull/4083.

Signed-off-by: Andrey Zabavnikov <zabavnikov@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 repository.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/repository.c b/repository.c
index 9825a3089932ed..4d7f6d5f25c50b 100644
--- a/repository.c
+++ b/repository.c
@@ -96,7 +96,7 @@ static void repo_set_commondir(struct repository *repo,
 {
 	struct strbuf sb = STRBUF_INIT;
 
-	free(repo->commondir);
+	FREE_AND_NULL(repo->commondir);
 
 	if (commondir) {
 		repo->different_commondir = 1;

From 6697363279964d05bd72515261d2f10ded23349c Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 27 Jan 2023 08:55:21 +0100
Subject: [PATCH 123/259] windows: skip linking `git-<command>` for built-ins

It is merely a historical wart that, say, `git-commit` exists in the
`libexec/git-core/` directory, a tribute to the original idea to let Git
be essentially a bunch of Unix shell scripts revolving around very few
"plumbing" (AKA low-level) commands.

Git has evolved a lot from there. These days, most of Git's
functionality is contained within the `git` executable, in the form of
"built-in" commands.

To accommodate for scripts that use the "dashed" form of Git commands,
even today, Git provides hard-links that make the `git` executable
available as, say, `git-commit`, just in case that an old script has not
been updated to invoke `git commit`.

Those hard-links do not come cheap: they take about half a minute for
every build of Git on Windows, they are mistaken for taking up huge
amounts of space by some Windows Explorer versions that do not
understand hard-links, and therefore many a "bug" report had to be
addressed.

The "dashed form" has been officially deprecated in Git version 1.5.4,
which was released on February 2nd, 2008, i.e. a very long time ago.
This deprecation was never finalized by skipping these hard-links, but
we can start the process now, in Git for Windows.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 config.mak.uname | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/config.mak.uname b/config.mak.uname
index bbf7744ddd5d0f..8615526ad36848 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -486,6 +486,7 @@ ifeq ($(uname_S),Windows)
 	NO_POSIX_GOODIES = UnfortunatelyYes
 	NATIVE_CRLF = YesPlease
 	DEFAULT_HELP_FORMAT = html
+	SKIP_DASHED_BUILT_INS = YabbaDabbaDoo
 ifeq (/mingw64,$(subst 32,64,$(prefix)))
 	# Move system config into top-level /etc/
 	ETC_GITCONFIG = ../etc/gitconfig
@@ -677,6 +678,7 @@ ifeq ($(uname_S),MINGW)
 	FSMONITOR_DAEMON_BACKEND = win32
 	FSMONITOR_OS_SETTINGS = win32
 
+	SKIP_DASHED_BUILT_INS = YabbaDabbaDoo
 	RUNTIME_PREFIX = YesPlease
 	HAVE_WPGMPTR = YesWeDo
 	NO_ST_BLOCKS_IN_STRUCT_STAT = YesPlease

From 8266ae86a3465acf5e0e820887cd9de5a5de893e Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 21 Mar 2023 16:14:44 +0100
Subject: [PATCH 124/259] windows: fix Repository>Explore Working Copy

Since Git v2.39.1, we are a bit more stringent in searching the PATH. In
particular, we specifically require the `.exe` suffix.

However, the `Repository>Explore Working Copy` command asks for
`explorer.exe` to be found on the `PATH`, which _already_ has that
suffix.

Let's unstartle the PATH-finding logic about this scenario.

This fixes https://github.com/git-for-windows/git/issues/4356

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 git-gui/git-gui.sh | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/git-gui/git-gui.sh b/git-gui/git-gui.sh
index 8fe7538e72084d..c299b38a64fb1e 100755
--- a/git-gui/git-gui.sh
+++ b/git-gui/git-gui.sh
@@ -101,6 +101,9 @@ proc _which {what args} {
 
 	if {[is_Windows] && [lsearch -exact $args -script] >= 0} {
 		set suffix {}
+	} elseif {[string match *$_search_exe $what]} {
+		# The search string already has the file extension
+		set suffix {}
 	} else {
 		set suffix $_search_exe
 	}

From e463c5f07be88c0c6d4e0683daf9f2d74f4f6741 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sun, 7 May 2023 22:05:33 +0200
Subject: [PATCH 125/259] http: when loading libcurl lazily, allow for multiple
 SSL backends

The previous commits introduced a compile-time option to load libcurl
lazily, but it uses the hard-coded name "libcurl-4.dll" (or equivalent
on platforms other than Windows).

To allow for installing multiple libcurl flavors side by side, where
each supports one specific SSL/TLS backend, let's first look whether
`libcurl-<backend>-4.dll` exists, and only use `libcurl-4.dll` as a fall
back.

That will allow us to ship with a libcurl by default that only supports
the Secure Channel backend for the `https://` protocol. This libcurl
won't suffer from any dependency problem when upgrading OpenSSL to a new
major version (which will change the DLL name, and hence break every
program and library that depends on it).

This is crucial because Git for Windows relies on libcurl to keep
working when building and deploying a new OpenSSL package because that
library is used by `git fetch` and `git clone`.

Note that this feature is by no means specific to Windows. On Ubuntu,
for example, a `git` built using `LAZY_LOAD_LIBCURL` will use
`libcurl.so.4` for `http.sslbackend=openssl` and `libcurl-gnutls.so.4`
for `http.sslbackend=gnutls`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/lazyload-curl.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/compat/lazyload-curl.c b/compat/lazyload-curl.c
index 98d73fb0f2a66f..2f2b2ebc27993e 100644
--- a/compat/lazyload-curl.c
+++ b/compat/lazyload-curl.c
@@ -172,17 +172,26 @@ static curl_easy_setopt_pointer_type curl_easy_setopt_pointer_func;
 typedef CURLcode (*curl_easy_setopt_off_t_type)(CURL *curl, CURLoption opt, curl_off_t value);
 static curl_easy_setopt_off_t_type curl_easy_setopt_off_t_func;
 
+static char ssl_backend[64];
+
 static void lazy_load_curl(void)
 {
 	static int initialized;
-	void *libcurl;
+	void *libcurl = NULL;
 	func_t curl_easy_getinfo_func, curl_easy_setopt_func;
 
 	if (initialized)
 		return;
 
 	initialized = 1;
-	libcurl = load_library(LIBCURL_FILE_NAME("libcurl"));
+	if (ssl_backend[0]) {
+		char dll_name[64 + 16];
+		snprintf(dll_name, sizeof(dll_name) - 1,
+			 LIBCURL_FILE_NAME("libcurl-%s"), ssl_backend);
+		libcurl = load_library(dll_name);
+	}
+	if (!libcurl)
+		libcurl = load_library(LIBCURL_FILE_NAME("libcurl"));
 	if (!libcurl)
 		die("failed to load library '%s'", LIBCURL_FILE_NAME("libcurl"));
 
@@ -246,6 +255,9 @@ CURLcode curl_global_init(long flags)
 
 CURLsslset curl_global_sslset(curl_sslbackend id, const char *name, const curl_ssl_backend ***avail)
 {
+	if (name && strlen(name) < sizeof(ssl_backend))
+		strlcpy(ssl_backend, name, sizeof(ssl_backend));
+
 	lazy_load_curl();
 	return curl_global_sslset_func(id, name, avail);
 }

From 246c04993537963b1b73b427093b49ce040eb0b5 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sun, 7 May 2023 22:43:37 +0200
Subject: [PATCH 126/259] mingw: do load libcurl dynamically by default

This will help with Git for Windows' maintenance going forward: It
allows Git for Windows to switch its primary libcurl to a variant
without the OpenSSL backend, while still loading an alternate when
setting `http.sslBackend = openssl`.

This is necessary to avoid maintenance headaches with upgrading OpenSSL:
its major version name is encoded in the shared library's file name and
hence major version updates (temporarily) break libraries that are
linked against the OpenSSL library.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 config.mak.uname | 1 +
 1 file changed, 1 insertion(+)

diff --git a/config.mak.uname b/config.mak.uname
index 33e75a076d715b..d198d5cf6913f4 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -692,6 +692,7 @@ ifeq ($(uname_S),MINGW)
 	HAVE_PLATFORM_PROCINFO = YesPlease
 	CSPRNG_METHOD = rtlgenrandom
 	BASIC_LDFLAGS += -municode -Wl,--tsaware
+	LAZYLOAD_LIBCURL = YesDoThatPlease
 	COMPAT_CFLAGS += -DNOGDI -Icompat -Icompat/win32
 	COMPAT_CFLAGS += -DSTRIP_EXTENSION=\".exe\"
 	COMPAT_OBJS += compat/mingw.o compat/winansi.o \

From 6f841b3d4c68a2ec1186e4b529fb97d1471f6b2f Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 2 Nov 2022 16:23:58 +0100
Subject: [PATCH 127/259] Add a GitHub workflow to verify that Git/Scalar work
 in Nano Server

In Git for Windows v2.39.0, we fixed a regression where `git.exe` would
no longer work in Windows Nano Server (frequently used in Docker
containers).

This GitHub workflow can be used to verify manually that the Git/Scalar
executables work in Nano Server.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 .github/workflows/nano-server.yml | 76 +++++++++++++++++++++++++++++++
 1 file changed, 76 insertions(+)
 create mode 100644 .github/workflows/nano-server.yml

diff --git a/.github/workflows/nano-server.yml b/.github/workflows/nano-server.yml
new file mode 100644
index 00000000000000..3d943c23d2616d
--- /dev/null
+++ b/.github/workflows/nano-server.yml
@@ -0,0 +1,76 @@
+name: Windows Nano Server tests
+
+on:
+  workflow_dispatch:
+
+env:
+  DEVELOPER: 1
+
+jobs:
+  test-nano-server:
+    runs-on: windows-2022
+    env:
+      WINDBG_DIR: "C:/Program Files (x86)/Windows Kits/10/Debuggers/x64"
+      IMAGE: mcr.microsoft.com/powershell:nanoserver-ltsc2022
+
+    steps:
+      - uses: actions/checkout@v4
+      - uses: git-for-windows/setup-git-for-windows-sdk@v1
+      - name: build Git
+        shell: bash
+        run: make -j15
+      - name: pull nanoserver image
+        shell: bash
+        run: docker pull $IMAGE
+      - name: run nano-server test
+        shell: bash
+        run: |
+          docker run \
+            --user "ContainerAdministrator" \
+            -v "$WINDBG_DIR:C:/dbg" \
+            -v "$(cygpath -aw /mingw64/bin):C:/mingw64-bin" \
+            -v "$(cygpath -aw .):C:/test" \
+            $IMAGE pwsh.exe -Command '
+              # Extend the PATH to include the `.dll` files in /mingw64/bin/
+              $env:PATH += ";C:\mingw64-bin"
+
+              # For each executable to test pick some no-operation set of
+              # flags/subcommands or something that should quickly result in an
+              # error with known exit code that is not a negative 32-bit
+              # number, and set the expected return code appropriately.
+              #
+              # Only test executables that could be expected to run in a UI
+              # less environment.
+              #
+              # ( Executable path, arguments, expected return code )
+              # also note space is required before close parenthesis (a
+              # powershell quirk when defining nested arrays like this)
+
+              $executables_to_test = @(
+                  ("C:\test\git.exe", "", 1 ),
+                  ("C:\test\scalar.exe", "version", 0 )
+              )
+
+              foreach ($executable in $executables_to_test)
+              {
+                  Write-Output "Now testing $($executable[0])"
+                  &$executable[0] $executable[1]
+                  if ($LASTEXITCODE -ne $executable[2]) {
+                      # if we failed, run the debugger to find out what function
+                      # or DLL could not be found and then exit the script with
+                      # failure The missing DLL or EXE will be referenced near
+                      # the end of the output
+
+                      # Set a flag to have the debugger show loader stub
+                      # diagnostics. This requires running as administrator,
+                      # otherwise the flag will be ignored.
+                      C:\dbg\gflags -i $executable[0] +SLS
+
+                      C:\dbg\cdb.exe -c "g" -c "q" $executable[0] $executable[1]
+
+                      exit 1
+                  }
+              }
+
+              exit 0
+            '

From 54f725f1d4b20dc7ad4d6da5d35eecc28d543c09 Mon Sep 17 00:00:00 2001
From: David Lomas <dl3@pale-eds.co.uk>
Date: Fri, 28 Jul 2023 15:31:25 +0100
Subject: [PATCH 128/259] mingw: suggest `windows.appendAtomically` in more
 cases

When running Git for Windows on a remote APFS filesystem, it would
appear that the `mingw_open_append()`/`write()` combination would fail
almost exactly like on some CIFS-mounted shares as had been reported in
https://github.com/git-for-windows/git/issues/2753, albeit with a
different `errno` value.

Let's handle that `errno` value just the same, by suggesting to set
`windows.appendAtomically=false`.

Signed-off-by: David Lomas <dl3@pale-eds.co.uk>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index d9477f9e5a4e64..8e64881f60c2d6 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -718,7 +718,7 @@ ssize_t mingw_write(int fd, const void *buf, size_t len)
 {
 	ssize_t result = write(fd, buf, len);
 
-	if (result < 0 && (errno == EINVAL || errno == ENOSPC) && buf) {
+	if (result < 0 && (errno == EINVAL || errno == EBADF || errno == ENOSPC) && buf) {
 		int orig = errno;
 
 		/* check if fd is a pipe */
@@ -744,7 +744,7 @@ ssize_t mingw_write(int fd, const void *buf, size_t len)
 			}
 
 			errno = orig;
-		} else if (orig == EINVAL)
+		} else if (orig == EINVAL || errno == EBADF)
 			errno = EPIPE;
 		else {
 			DWORD buf_size;

From ba87a0db0c350ebfcaeb662eee48c97d6412793d Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 22 Nov 2023 22:57:38 +0100
Subject: [PATCH 129/259] win32: use native ANSI sequence processing, if
 possible

Windows 10 version 1511 (also known as Anniversary Update), according to
https://learn.microsoft.com/en-us/windows/console/console-virtual-terminal-sequences
introduced native support for ANSI sequence processing. This allows
using colors from the entire 24-bit color range.

All we need to do is test whether the console's "virtual processing
support" can be enabled. If it can, we do not even need to start the
`console_thread` to handle ANSI sequences.

Or, almost all we need to do: When `console_thread()` does its work, it
uses the Unicode-aware `write_console()` function to write to the Win32
Console, which supports Git for Windows' implicit convention that all
text that is written is encoded in UTF-8. The same is not necessarily
true if native ANSI sequence processing is used, as the output is then
subject to the current code page. Let's ensure that the code page is set
to `CP_UTF8` as long as Git writes to it.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/winansi.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/compat/winansi.c b/compat/winansi.c
index 575813bde8e806..95647a9520941e 100644
--- a/compat/winansi.c
+++ b/compat/winansi.c
@@ -591,6 +591,49 @@ static void detect_msys_tty(int fd)
 
 #endif
 
+static HANDLE std_console_handle;
+static DWORD std_console_mode = ENABLE_VIRTUAL_TERMINAL_PROCESSING;
+static UINT std_console_code_page = CP_UTF8;
+
+static void reset_std_console(void)
+{
+	if (std_console_mode != ENABLE_VIRTUAL_TERMINAL_PROCESSING)
+		SetConsoleMode(std_console_handle, std_console_mode);
+	if (std_console_code_page != CP_UTF8)
+		SetConsoleOutputCP(std_console_code_page);
+}
+
+static int enable_virtual_processing(void)
+{
+	std_console_handle = GetStdHandle(STD_OUTPUT_HANDLE);
+	if (std_console_handle == INVALID_HANDLE_VALUE ||
+	    !GetConsoleMode(std_console_handle, &std_console_mode)) {
+		std_console_handle = GetStdHandle(STD_ERROR_HANDLE);
+		if (std_console_handle == INVALID_HANDLE_VALUE ||
+		    !GetConsoleMode(std_console_handle, &std_console_mode))
+		return 0;
+	}
+
+	std_console_code_page = GetConsoleOutputCP();
+	if (std_console_code_page != CP_UTF8)
+		SetConsoleOutputCP(CP_UTF8);
+	if (!std_console_code_page)
+		std_console_code_page = CP_UTF8;
+
+	atexit(reset_std_console);
+
+	if (std_console_mode & ENABLE_VIRTUAL_TERMINAL_PROCESSING)
+		return 1;
+
+	if (!SetConsoleMode(std_console_handle,
+			    std_console_mode |
+			    ENABLE_PROCESSED_OUTPUT |
+			    ENABLE_VIRTUAL_TERMINAL_PROCESSING))
+		return 0;
+
+	return 1;
+}
+
 /*
  * Wrapper for isatty().  Most calls in the main git code
  * call isatty(1 or 2) to see if the instance is interactive
@@ -629,6 +672,9 @@ void winansi_init(void)
 		return;
 	}
 
+	if (enable_virtual_processing())
+		return;
+
 	/* create a named pipe to communicate with the console thread */
 	if (swprintf(name, ARRAY_SIZE(name) - 1, L"\\\\.\\pipe\\winansi%lu",
 		     GetCurrentProcessId()) < 0)

From e9fc25a84c46fceda4ef414932c559ad06b7c372 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Matthias=20A=C3=9Fhauer?= <mha1993@live.de>
Date: Sat, 2 Dec 2023 12:10:00 +0100
Subject: [PATCH 130/259] git.rc: include winuser.h
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

winuser.h contains the definition of RT_MANIFEST that our LLVM based
toolchain needs to understand that we want to embed
compat/win32/git.manifest as an application manifest. It currently just
embeds it as additional data that Windows doesn't understand.

This also helps our GCC based toolchain understand that we only want one
copy embedded. It currently embeds one working assembly manifest and one
nearly identical, but useless copy as additional data.

This also teaches our Visual Studio based buildsystems to pick up the
manifest file from git.rc. This means we don't have to explicitly specify
it in contrib/buildsystems/Generators/Vcxproj.pm anymore. Slightly
counter-intuitively this also means we have to explicitly tell Cmake
not to embed a default manifest.

This fixes https://github.com/git-for-windows/git/issues/4707

Signed-off-by: Matthias Aßhauer <mha1993@live.de>
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
---
 contrib/buildsystems/CMakeLists.txt        | 1 +
 contrib/buildsystems/Generators/Vcxproj.pm | 1 -
 git.rc                                     | 1 +
 3 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index 832f46b316b764..26aac0702be3c9 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -219,6 +219,7 @@ if(CMAKE_C_COMPILER_ID STREQUAL "MSVC")
 	set(CMAKE_RUNTIME_OUTPUT_DIRECTORY_DEBUG ${CMAKE_BINARY_DIR})
 	set(CMAKE_RUNTIME_OUTPUT_DIRECTORY_RELEASE ${CMAKE_BINARY_DIR})
 	add_compile_options(/MP /std:c11)
+	add_link_options(/MANIFEST:NO)
 endif()
 
 #default behaviour
diff --git a/contrib/buildsystems/Generators/Vcxproj.pm b/contrib/buildsystems/Generators/Vcxproj.pm
index a6d1c6b8d05682..7a62542eed152b 100644
--- a/contrib/buildsystems/Generators/Vcxproj.pm
+++ b/contrib/buildsystems/Generators/Vcxproj.pm
@@ -187,7 +187,6 @@ sub createProject {
       <AdditionalDependencies>\$(VCPKGLibs);\$(AdditionalDependencies)</AdditionalDependencies>
       <AdditionalOptions>invalidcontinue.obj %(AdditionalOptions)</AdditionalOptions>
       <EntryPointSymbol>$entrypoint</EntryPointSymbol>
-      <ManifestFile>$cdup\\compat\\win32\\git.manifest</ManifestFile>
       <SubSystem>$subsystem</SubSystem>
     </Link>
 EOM
diff --git a/git.rc b/git.rc
index cc3fdc6cc6cb83..a318a53c12af58 100644
--- a/git.rc
+++ b/git.rc
@@ -1,3 +1,4 @@
+#include<winuser.h>
 1 VERSIONINFO
 FILEVERSION     MAJOR,MINOR,MICRO,PATCHLEVEL
 PRODUCTVERSION  MAJOR,MINOR,MICRO,PATCHLEVEL

From db40bb9b259e0053f56b0376b126af79a2b77053 Mon Sep 17 00:00:00 2001
From: MinarKotonoha <chengzhuo5@qq.com>
Date: Mon, 8 Apr 2024 16:41:10 +0800
Subject: [PATCH 131/259] common-main.c: fflush stdout buffer upon exit

By default, the buffer type of Windows' `stdout` is unbuffered (_IONBF),
and there is no need to manually fflush `stdout`.

But some programs, such as the Windows Filtering Platform driver
provided by the security software, may change the buffer type of
`stdout` to full buffering. This nees `fflush(stdout)` to be called
manually, otherwise there will be no output to `stdout`.

Signed-off-by: MinarKotonoha <chengzhuo5@qq.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 common-main.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/common-main.c b/common-main.c
index 8e68ac9e42993d..75cf58abf645f0 100644
--- a/common-main.c
+++ b/common-main.c
@@ -77,6 +77,13 @@ static void check_bug_if_BUG(void)
 /* We wrap exit() to call common_exit() in git-compat-util.h */
 int common_exit(const char *file, int line, int code)
 {
+	/*
+	 *  Windows Filtering Platform driver provided by the security software
+	 * may change buffer type of stdout from _IONBF to _IOFBF.
+	 * It will no output without fflush manually.
+	 */
+	fflush(stdout);
+
 	/*
 	 * For non-POSIX systems: Take the lowest 8 bits of the "code"
 	 * to e.g. turn -1 into 255. On a POSIX system this is

From 55a95de13ce1be68cd445b8ef12f9f3b145b10be Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 9 Apr 2024 16:50:56 +0200
Subject: [PATCH 132/259] t5601/t7406(mingw): do run tests with symlink support

A long time ago, we decided to run tests in Git for Windows' SDK with
the default `winsymlinks` mode: copying instead of linking. This is
still the default mode of MSYS2 to this day.

However, this is not how most users run Git for Windows: As the majority
of Git for Windows' users seem to be on Windows 10 and newer, likely
having enabled Developer Mode (which allows creating symbolic links
without administrator privileges), they will run with symlink support
enabled.

This is the reason why it is crucial to get the fixes for CVE-2024-? to
the users, and also why it is crucial to ensure that the test suite
exercises the related test cases. This commit ensures the latter.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t5601-clone.sh            | 10 ++++++++++
 t/t7406-submodule-update.sh |  9 +++++++++
 2 files changed, 19 insertions(+)

diff --git a/t/t5601-clone.sh b/t/t5601-clone.sh
index 5d7ea147f1abc5..128c8f12468f17 100755
--- a/t/t5601-clone.sh
+++ b/t/t5601-clone.sh
@@ -7,6 +7,16 @@ export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
 . ./test-lib.sh
 
+# This test script contains test cases that need to create symbolic links. To
+# make sure that these test cases are exercised in Git for Windows, where (for
+# historical reasons) `ln -s` creates copies by default, let's specifically ask
+# for `ln -s` to create symbolic links whenever possible.
+if test_have_prereq MINGW
+then
+	MSYS=${MSYS+$MSYS }winsymlinks:nativestrict
+	export MSYS
+fi
+
 X=
 test_have_prereq !MINGW || X=.exe
 
diff --git a/t/t7406-submodule-update.sh b/t/t7406-submodule-update.sh
index 297c6c3b5cc4b8..80647e440f7093 100755
--- a/t/t7406-submodule-update.sh
+++ b/t/t7406-submodule-update.sh
@@ -14,6 +14,15 @@ export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
 . ./test-lib.sh
 
+# This test script contains test cases that need to create symbolic links. To
+# make sure that these test cases are exercised in Git for Windows, where (for
+# historical reasons) `ln -s` creates copies by default, let's specifically ask
+# for `ln -s` to create symbolic links whenever possible.
+if test_have_prereq MINGW
+then
+	MSYS=${MSYS+$MSYS }winsymlinks:nativestrict
+	export MSYS
+fi
 
 compare_head()
 {

From 0b4961d58c51df8a25ba68bb9a3a764a54cfd8fe Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 21 May 2024 13:55:26 +0200
Subject: [PATCH 133/259] win32: ensure that `localtime_r()` is declared even
 in i686 builds

The `__MINGW64__` constant is defined, surprise, surprise, only when
building for a 64-bit CPU architecture.

Therefore using it as a guard to define `_POSIX_C_SOURCE` (so that
`localtime_r()` is declared, among other functions) is not enough, we
also need to check `__MINGW32__`.

Technically, the latter constant is defined even for 64-bit builds. But
let's make things a bit easier to understand by testing for both
constants.

Making it so fixes this compile warning (turned error in GCC v14.1):

  archive-zip.c: In function 'dos_time':
  archive-zip.c:612:9: error: implicit declaration of function 'localtime_r';
  did you mean 'localtime_s'? [-Wimplicit-function-declaration]
    612 |         localtime_r(&time, &tm);
        |         ^~~~~~~~~~~
        |         localtime_s

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 git-compat-util.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/git-compat-util.h b/git-compat-util.h
index 71b4d23f0386b2..96dcca54416b75 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -166,7 +166,7 @@ struct strbuf;
 /* Approximation of the length of the decimal representation of this type. */
 #define decimal_length(x)	((int)(sizeof(x) * 2.56 + 0.5) + 1)
 
-#ifdef __MINGW64__
+#if defined(__MINGW32__) || defined(__MINGW64__)
 #define _POSIX_C_SOURCE 1
 #elif defined(__sun__)
  /*

From 3f2c20a4505bc6bac13e597b052ba9acf6242629 Mon Sep 17 00:00:00 2001
From: Derrick Stolee <stolee@gmail.com>
Date: Sat, 7 Sep 2024 19:43:45 -0400
Subject: [PATCH 134/259] pack-objects: add --full-name-hash option

The pack_name_hash() method has not been materially changed since it was
introduced in ce0bd64299a (pack-objects: improve path grouping
heuristics., 2006-06-05). The intention here is to group objects by path
name, but also attempt to group similar file types together by making
the most-significant digits of the hash be focused on the final
characters.

Here's the crux of the implementation:

	/*
	 * This effectively just creates a sortable number from the
	 * last sixteen non-whitespace characters. Last characters
	 * count "most", so things that end in ".c" sort together.
	 */
	while ((c = *name++) != 0) {
		if (isspace(c))
			continue;
		hash = (hash >> 2) + (c << 24);
	}

As the comment mentions, this only cares about the last sixteen
non-whitespace characters. This cause some filenames to collide more
than others. Here are some examples that I've seen while investigating
repositories that are growing more than they should be:

 * "/CHANGELOG.json" is 15 characters, and is created by the beachball
   [1] tool. Only the final character of the parent directory can
   differntiate different versions of this file, but also only the two
   most-significant digits. If that character is a letter, then this is
   always a collision. Similar issues occur with the similar
   "/CHANGELOG.md" path, though there is more opportunity for
   differences in the parent directory.

 * Localization files frequently have common filenames but differentiate
   via parent directories. In C#, the name "/strings.resx.lcl" is used
   for these localization files and they will all collide in name-hash.

[1] https://github.com/microsoft/beachball

I've come across many other examples where some internal tool uses a
common name across multiple directories and is causing Git to repack
poorly due to name-hash collisions.

It is clear that the existing name-hash algorithm is optimized for
repositories with short path names, but also is optimized for packing a
single snapshot of a repository, not a repository with many versions of
the same file. In my testing, this has proven out where the name-hash
algorithm does a good job of finding peer files as delta bases when
unable to use a historical version of that exact file.

However, for repositories that have many versions of most files and
directories, it is more important that the objects that appear at the
same path are grouped together.

Create a new pack_full_name_hash() method and a new --full-name-hash
option for 'git pack-objects' to call that method instead. Add a simple
pass-through for 'git repack --full-name-hash' for additional testing in
the context of a full repack, where I expect this will be most
effective.

The hash algorithm is as simple as possible to be reasonably effective:
for each character of the path string, add a multiple of that character
and a large prime number (chosen arbitrarily, but intended to be large
relative to the size of a uint32_t). Then, shift the current hash value
to the right by 5, with overlap. The addition and shift parameters are
standard mechanisms for creating hard-to-predict behaviors in the bits
of the resulting hash.

This is not meant to be cryptographic at all, but uniformly distributed
across the possible hash values. This creates a hash that appears
pseudorandom. There is no ability to consider similar file types as
being close to each other.

In a later change, a test-tool will be added so the effectiveness of
this hash can be demonstrated directly.

For now, let's consider how effective this mechanism is when repacking a
repository with and without the --full-name-hash option. Specifically,
let's use 'git repack -adf [--full-name-hash]' as our test.

On the Git repository, we do not expect much difference. All path names
are short. This is backed by our results:

| Stage                 | Pack Size | Repack Time |
|-----------------------|-----------|-------------|
| After clone           | 260 MB    | N/A         |
| Standard Repack       | 127MB     | 106s        |
| With --full-name-hash | 126 MB    | 99s         |

This example demonstrates how there is some natural overhead coming from
the cloned copy because the server is hosting many forks and has not
optimized for exactly this set of reachable objects. But the full repack
has similar characteristics with and without --full-name-hash.

However, we can test this in a repository that uses one of the
problematic naming conventions above. The fluentui [2] repo uses
beachball to generate CHANGELOG.json and CHANGELOG.md files, and these
files have very poor delta characteristics when comparing against
versions across parent directories.

| Stage                 | Pack Size | Repack Time |
|-----------------------|-----------|-------------|
| After clone           | 694 MB    | N/A         |
| Standard Repack       | 438 MB    | 728s        |
| With --full-name-hash | 168 MB    | 142s        |

[2] https://github.com/microsoft/fluentui

In this example, we see significant gains in the compressed packfile
size as well as the time taken to compute the packfile.

Using a collection of repositories that use the beachball tool, I was
able to make similar comparisions with dramatic results. While the
fluentui repo is public, the others are private so cannot be shared for
reproduction. The results are so significant that I find it important to
share here:

| Repo     | Standard Repack | With --full-name-hash |
|----------|-----------------|-----------------------|
| fluentui |         438 MB  |               168 MB  |
| Repo B   |       6,255 MB  |               829 MB  |
| Repo C   |      37,737 MB  |             7,125 MB  |
| Repo D   |     130,049 MB  |             6,190 MB  |

Future changes could include making --full-name-hash implied by a config
value or even implied by default during a full repack.

Signed-off-by: Derrick Stolee <stolee@gmail.com>
---
 Documentation/git-pack-objects.txt |  3 ++-
 builtin/pack-objects.c             | 23 ++++++++++++++++++-----
 builtin/repack.c                   |  5 +++++
 pack-objects.h                     | 21 +++++++++++++++++++++
 t/t5300-pack-object.sh             | 15 +++++++++++++++
 5 files changed, 61 insertions(+), 6 deletions(-)

diff --git a/Documentation/git-pack-objects.txt b/Documentation/git-pack-objects.txt
index e32404c6aaee30..93861d9f85b3b1 100644
--- a/Documentation/git-pack-objects.txt
+++ b/Documentation/git-pack-objects.txt
@@ -15,7 +15,8 @@ SYNOPSIS
 	[--revs [--unpacked | --all]] [--keep-pack=<pack-name>]
 	[--cruft] [--cruft-expiration=<time>]
 	[--stdout [--filter=<filter-spec>] | <base-name>]
-	[--shallow] [--keep-true-parents] [--[no-]sparse] < <object-list>
+	[--shallow] [--keep-true-parents] [--[no-]sparse]
+	[--full-name-hash] < <object-list>
 
 
 DESCRIPTION
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index f395488971f9c5..919be27b2ac8c6 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -266,6 +266,14 @@ struct configured_exclusion {
 static struct oidmap configured_exclusions;
 
 static struct oidset excluded_by_config;
+static int use_full_name_hash;
+
+static inline uint32_t pack_name_hash_fn(const char *name)
+{
+	if (use_full_name_hash)
+		return pack_full_name_hash(name);
+	return pack_name_hash(name);
+}
 
 /*
  * stats
@@ -1670,7 +1678,7 @@ static int add_object_entry(const struct object_id *oid, enum object_type type,
 		return 0;
 	}
 
-	create_object_entry(oid, type, pack_name_hash(name),
+	create_object_entry(oid, type, pack_name_hash_fn(name),
 			    exclude, name && no_try_delta(name),
 			    found_pack, found_offset);
 	return 1;
@@ -1884,7 +1892,7 @@ static void add_preferred_base_object(const char *name)
 {
 	struct pbase_tree *it;
 	size_t cmplen;
-	unsigned hash = pack_name_hash(name);
+	unsigned hash = pack_name_hash_fn(name);
 
 	if (!num_preferred_base || check_pbase_path(hash))
 		return;
@@ -3394,7 +3402,7 @@ static void show_object_pack_hint(struct object *object, const char *name,
 	 * here using a now in order to perhaps improve the delta selection
 	 * process.
 	 */
-	oe->hash = pack_name_hash(name);
+	oe->hash = pack_name_hash_fn(name);
 	oe->no_try_delta = name && no_try_delta(name);
 
 	stdin_packs_hints_nr++;
@@ -3544,7 +3552,7 @@ static void add_cruft_object_entry(const struct object_id *oid, enum object_type
 	entry = packlist_find(&to_pack, oid);
 	if (entry) {
 		if (name) {
-			entry->hash = pack_name_hash(name);
+			entry->hash = pack_name_hash_fn(name);
 			entry->no_try_delta = no_try_delta(name);
 		}
 	} else {
@@ -3567,7 +3575,7 @@ static void add_cruft_object_entry(const struct object_id *oid, enum object_type
 			return;
 		}
 
-		entry = create_object_entry(oid, type, pack_name_hash(name),
+		entry = create_object_entry(oid, type, pack_name_hash_fn(name),
 					    0, name && no_try_delta(name),
 					    pack, offset);
 	}
@@ -4397,6 +4405,8 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
 		OPT_STRING_LIST(0, "uri-protocol", &uri_protocols,
 				N_("protocol"),
 				N_("exclude any configured uploadpack.blobpackfileuri with this protocol")),
+		OPT_BOOL(0, "full-name-hash", &use_full_name_hash,
+			 N_("optimize delta compression across identical path names over time")),
 		OPT_END(),
 	};
 
@@ -4544,6 +4554,9 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
 	if (pack_to_stdout || !rev_list_all)
 		write_bitmap_index = 0;
 
+	if (write_bitmap_index && use_full_name_hash)
+		die(_("currently, the --full-name-hash option is incompatible with --write-bitmap-index"));
+
 	if (use_delta_islands)
 		strvec_push(&rp, "--topo-order");
 
diff --git a/builtin/repack.c b/builtin/repack.c
index f0317fa94ad46c..3977ed003147ad 100644
--- a/builtin/repack.c
+++ b/builtin/repack.c
@@ -57,6 +57,7 @@ struct pack_objects_args {
 	int no_reuse_object;
 	int quiet;
 	int local;
+	int full_name_hash;
 	struct list_objects_filter_options filter_options;
 };
 
@@ -288,6 +289,8 @@ static void prepare_pack_objects(struct child_process *cmd,
 		strvec_pushf(&cmd->args, "--no-reuse-delta");
 	if (args->no_reuse_object)
 		strvec_pushf(&cmd->args, "--no-reuse-object");
+	if (args->full_name_hash)
+		strvec_pushf(&cmd->args, "--full-name-hash");
 	if (args->local)
 		strvec_push(&cmd->args,  "--local");
 	if (args->quiet)
@@ -1157,6 +1160,8 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
 				N_("pass --no-reuse-delta to git-pack-objects")),
 		OPT_BOOL('F', NULL, &po_args.no_reuse_object,
 				N_("pass --no-reuse-object to git-pack-objects")),
+		OPT_BOOL(0, "full-name-hash", &po_args.full_name_hash,
+				N_("pass --full-name-hash to git-pack-objects")),
 		OPT_NEGBIT('n', NULL, &run_update_server_info,
 				N_("do not run git-update-server-info"), 1),
 		OPT__QUIET(&po_args.quiet, N_("be quiet")),
diff --git a/pack-objects.h b/pack-objects.h
index b9898a4e64b8b4..88360aa3e8e79d 100644
--- a/pack-objects.h
+++ b/pack-objects.h
@@ -207,6 +207,27 @@ static inline uint32_t pack_name_hash(const char *name)
 	return hash;
 }
 
+static inline uint32_t pack_full_name_hash(const char *name)
+{
+	const uint32_t bigp = 1234572167U;
+	uint32_t c, hash = bigp;
+
+	if (!name)
+		return 0;
+
+	/*
+	 * Do the simplest thing that will resemble pseudo-randomness: add
+	 * random multiples of a large prime number with a binary shift.
+	 * The goal is not to be cryptographic, but to be generally
+	 * uniformly distributed.
+	 */
+	while ((c = *name++) != 0) {
+		hash += c * bigp;
+		hash = (hash >> 5) | (hash << 27);
+	}
+	return hash;
+}
+
 static inline enum object_type oe_type(const struct object_entry *e)
 {
 	return e->type_valid ? e->type_ : OBJ_BAD;
diff --git a/t/t5300-pack-object.sh b/t/t5300-pack-object.sh
index 3b9dae331a5ea9..fff49000c31971 100755
--- a/t/t5300-pack-object.sh
+++ b/t/t5300-pack-object.sh
@@ -674,4 +674,19 @@ do
 	'
 done
 
+# The following test is not necessarily a permanent choice, but since we do not
+# have a "name hash version" bit in the .bitmap file format, we cannot write the
+# full-name hash values into the .bitmap file without risking breakage later.
+#
+# TODO: Make these compatible in the future and replace this test with the
+# expected behavior when both are specified.
+test_expect_success '--full-name-hash and --write-bitmap-index are incompatible' '
+	test_must_fail git pack-objects base --all \
+		--full-name-hash --write-bitmap-index 2>err &&
+	grep incompatible err &&
+
+	# --stdout option silently removes --write-bitmap-index
+	git pack-objects --stdout --all --full-name-hash --write-bitmap-index >out
+'
+
 test_done

From 391cd2a8b777609887e76da8bb9d5405856416ff Mon Sep 17 00:00:00 2001
From: Ariel Lourenco <ariellourenco@users.noreply.github.com>
Date: Tue, 2 Jul 2024 18:09:43 -0300
Subject: [PATCH 135/259] Fallback to AppData if XDG_CONFIG_HOME is unset

In order to be a better Windows citizenship, Git should
save its configuration files on AppData folder. This can
enables git configuration files be replicated between machines
using the same Microsoft account logon which would reduce the
friction of setting up Git on new systems. Therefore, if
%APPDATA%\Git\config exists, we use it; otherwise
$HOME/.config/git/config is used.

Signed-off-by: Ariel Lourenco <ariellourenco@users.noreply.github.com>
---
 path.c | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/path.c b/path.c
index 19f7684f3876bd..0e307b0a9b734b 100644
--- a/path.c
+++ b/path.c
@@ -1484,6 +1484,7 @@ int looks_like_command_line_option(const char *str)
 char *xdg_config_home_for(const char *subdir, const char *filename)
 {
 	const char *home, *config_home;
+	char *home_config = NULL;
 
 	assert(subdir);
 	assert(filename);
@@ -1492,10 +1493,26 @@ char *xdg_config_home_for(const char *subdir, const char *filename)
 		return mkpathdup("%s/%s/%s", config_home, subdir, filename);
 
 	home = getenv("HOME");
-	if (home)
-		return mkpathdup("%s/.config/%s/%s", home, subdir, filename);
+	if (home && *home)
+		home_config = mkpathdup("%s/.config/%s/%s", home, subdir, filename);
+
+	#ifdef WIN32
+	{
+		const char *appdata = getenv("APPDATA");
+		if (appdata && *appdata) {
+			char *appdata_config = mkpathdup("%s/Git/%s", appdata, filename);
+			if (file_exists(appdata_config)) {
+				if (home_config && file_exists(home_config))
+					warning("'%s' was ignored because '%s' exists.", home_config, appdata_config);
+				free(home_config);
+				return appdata_config;
+			}
+			free(appdata_config);
+		}
+	}
+	#endif
 
-	return NULL;
+	return home_config;
 }
 
 char *xdg_config_home(const char *filename)

From 2d4c3f42655c14229d748995d588348c8731c0de Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 4 Jul 2024 22:41:56 +0200
Subject: [PATCH 136/259] run-command: be helpful with Git LFS fails on Windows
 7

Git LFS is now built with Go 1.21 which no longer supports Windows 7.
However, Git for Windows still wants to support Windows 7.

Ideally, Git LFS would re-introduce Windows 7 support until Git for
Windows drops support for Windows 7, but that's not going to happen:
https://github.com/git-for-windows/git/issues/4996#issuecomment-2176152565

The next best thing we can do is to let the users know what is
happening, and how to get out of their fix, at least.

This is not quite as easy as it would first seem because programs
compiled with Go 1.21 or newer will simply throw an exception and fail
with an Access Violation on Windows 7.

The only way I found to address this is to replicate the logic from Go's
very own `version` command (which can determine the Go version with
which a given executable was built) to detect the situation, and in that
case offer a helpful error message.

This addresses https://github.com/git-for-windows/git/issues/4996.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/win32/path-utils.c | 199 ++++++++++++++++++++++++++++++++++++++
 compat/win32/path-utils.h |   3 +
 git-compat-util.h         |   6 ++
 run-command.c             |   1 +
 4 files changed, 209 insertions(+)

diff --git a/compat/win32/path-utils.c b/compat/win32/path-utils.c
index b658ca3f811717..be43d328db7b3a 100644
--- a/compat/win32/path-utils.c
+++ b/compat/win32/path-utils.c
@@ -1,5 +1,8 @@
 #include "../../git-compat-util.h"
 #include "../../environment.h"
+#include "../../wrapper.h"
+#include "../../strbuf.h"
+#include "../../versioncmp.h"
 
 int win32_has_dos_drive_prefix(const char *path)
 {
@@ -87,3 +90,199 @@ int win32_fspathcmp(const char *a, const char *b)
 {
 	return win32_fspathncmp(a, b, (size_t)-1);
 }
+
+static int read_at(int fd, char *buffer, size_t offset, size_t size)
+{
+	if (lseek(fd, offset, SEEK_SET) < 0) {
+		fprintf(stderr, "could not seek to 0x%x\n", (unsigned int)offset);
+		return -1;
+	}
+
+	return read_in_full(fd, buffer, size);
+}
+
+static size_t le16(const char *buffer)
+{
+	unsigned char *u = (unsigned char *)buffer;
+	return u[0] | (u[1] << 8);
+}
+
+static size_t le32(const char *buffer)
+{
+	return le16(buffer) | (le16(buffer + 2) << 16);
+}
+
+/*
+ * Determine the Go version of a given executable, if it was built with Go.
+ *
+ * This recapitulates the logic from
+ * https://github.com/golang/go/blob/master/src/cmd/go/internal/version/version.go
+ * (without requiring the user to install `go.exe` to find out).
+ */
+static ssize_t get_go_version(const char *path, char *go_version, size_t go_version_size)
+{
+	int fd = open(path, O_RDONLY);
+	char buffer[1024];
+	off_t offset;
+	size_t num_sections, opt_header_size, i;
+	char *p = NULL, *q;
+	ssize_t res = -1;
+
+	if (fd < 0)
+		return -1;
+
+	if (read_in_full(fd, buffer, 2) < 0)
+		goto fail;
+
+	/*
+	 * Parse the PE file format, for more details, see
+	 * https://en.wikipedia.org/wiki/Portable_Executable#Layout and
+	 * https://learn.microsoft.com/en-us/windows/win32/debug/pe-format
+	 */
+	if (buffer[0] != 'M' || buffer[1] != 'Z')
+		goto fail;
+
+	if (read_at(fd, buffer, 0x3c, 4) < 0)
+		goto fail;
+
+	/* Read the `PE\0\0` signature and the COFF file header */
+	offset = le32(buffer);
+	if (read_at(fd, buffer, offset, 24) < 0)
+		goto fail;
+
+	if (buffer[0] != 'P' || buffer[1] != 'E' || buffer[2] != '\0' || buffer[3] != '\0')
+		goto fail;
+
+	num_sections = le16(buffer + 6);
+	opt_header_size = le16(buffer + 20);
+	offset += 24; /* skip file header */
+
+	/*
+	 * Validate magic number 0x10b or 0x20b, for full details see
+	 * https://learn.microsoft.com/en-us/windows/win32/debug/pe-format#optional-header-standard-fields-image-only
+	 */
+	if (read_at(fd, buffer, offset, 2) < 0 ||
+	    ((i = le16(buffer)) != 0x10b && i != 0x20b))
+		goto fail;
+
+	offset += opt_header_size;
+
+	for (i = 0; i < num_sections; i++) {
+		if (read_at(fd, buffer, offset + i * 40, 40) < 0)
+			goto fail;
+
+		/*
+		 * For full details about the section headers, see
+		 * https://learn.microsoft.com/en-us/windows/win32/debug/pe-format#section-table-section-headers
+		 */
+		if ((le32(buffer + 36) /* characteristics */ & ~0x600000) /* IMAGE_SCN_ALIGN_32BYTES */ ==
+		    (/* IMAGE_SCN_CNT_INITIALIZED_DATA */ 0x00000040 |
+		     /* IMAGE_SCN_MEM_READ */ 0x40000000 |
+		     /* IMAGE_SCN_MEM_WRITE */ 0x80000000)) {
+			size_t size = le32(buffer + 16); /* "SizeOfRawData " */
+			size_t pointer = le32(buffer + 20); /* "PointerToRawData " */
+
+			/*
+			 * Skip the section if either size or pointer is 0, see
+			 * https://github.com/golang/go/blob/go1.21.0/src/debug/buildinfo/buildinfo.go#L333
+			 * for full details.
+			 *
+			 * Merely seeing a non-zero size will not actually do,
+			 * though: he size must be at least `buildInfoSize`,
+			 * i.e. 32, and we expect a UVarint (at least another
+			 * byte) _and_ the bytes representing the string,
+			 * which we expect to start with the letters "go" and
+			 * continue with the Go version number.
+			 */
+			if (size < 32 + 1 + 2 + 1 || !pointer)
+				continue;
+
+			p = malloc(size);
+
+			if (!p || read_at(fd, p, pointer, size) < 0)
+				goto fail;
+
+			/*
+			 * Look for the build information embedded by Go, see
+			 * https://github.com/golang/go/blob/go1.21.0/src/debug/buildinfo/buildinfo.go#L165-L175
+			 * for full details.
+			 *
+			 * Note: Go contains code to enforce alignment along a
+			 * 16-byte boundary. In practice, no `.exe` has been
+			 * observed that required any adjustment, therefore
+			 * this here code skips that logic for simplicity.
+			 */
+			q = memmem(p, size - 18, "\xff Go buildinf:", 14);
+			if (!q)
+				goto fail;
+			/*
+			 * Decode the build blob. For full details, see
+			 * https://github.com/golang/go/blob/go1.21.0/src/debug/buildinfo/buildinfo.go#L177-L191
+			 *
+			 * Note: The `endianness` values observed in practice
+			 * were always 2, therefore the complex logic to handle
+			 * any other value is skipped for simplicty.
+			 */
+			if ((q[14] == 8 || q[14] == 4) && q[15] == 2) {
+				/*
+				 * Only handle a Go version string with fewer
+				 * than 128 characters, so the Go UVarint at
+				 * q[32] that indicates the string's length must
+				 * be only one byte (without the high bit set).
+				 */
+				if ((q[32] & 0x80) ||
+				    !q[32] ||
+				    (q + 33 + q[32] - p) > size ||
+				    q[32] + 1 > go_version_size)
+					goto fail;
+				res = q[32];
+				memcpy(go_version, q + 33, res);
+				go_version[res] = '\0';
+				break;
+			}
+		}
+	}
+
+fail:
+	free(p);
+	close(fd);
+	return res;
+}
+
+void win32_warn_about_git_lfs_on_windows7(int exit_code, const char *argv0)
+{
+	char buffer[128], *git_lfs = NULL;
+	const char *p;
+
+	/*
+	 * Git LFS v3.5.1 fails with an Access Violation on Windows 7; That
+	 * would usually show up as an exit code 0xc0000005. For some reason
+	 * (probably because at this point, we no longer have the _original_
+	 * HANDLE that was returned by `CreateProcess()`) we observe other
+	 * values like 0xb00 and 0x2 instead. Since the exact exit code
+	 * seems to be inconsistent, we check for a non-zero exit status.
+	 */
+	if (exit_code == 0)
+		return;
+	if (GetVersion() >> 16 > 7601)
+		return; /* Warn only on Windows 7 or older */
+	if (!istarts_with(argv0, "git-lfs ") &&
+	    strcasecmp(argv0, "git-lfs"))
+		return;
+	if (!(git_lfs = locate_in_PATH("git-lfs")))
+		return;
+	if (get_go_version(git_lfs, buffer, sizeof(buffer)) > 0 &&
+	    skip_prefix(buffer, "go", &p) &&
+	    versioncmp("1.21.0", p) <= 0)
+		warning("This program was built with Go v%s\n"
+			"i.e. without support for this Windows version:\n"
+			"\n\t%s\n"
+			"\n"
+			"To work around this, you can download and install a "
+			"working version from\n"
+			"\n"
+			"\thttps://github.com/git-lfs/git-lfs/releases/tag/"
+			"v3.4.1\n",
+			p, git_lfs);
+	free(git_lfs);
+}
diff --git a/compat/win32/path-utils.h b/compat/win32/path-utils.h
index a561c700e75713..a69483c332c1a7 100644
--- a/compat/win32/path-utils.h
+++ b/compat/win32/path-utils.h
@@ -34,4 +34,7 @@ int win32_fspathcmp(const char *a, const char *b);
 int win32_fspathncmp(const char *a, const char *b, size_t count);
 #define fspathncmp win32_fspathncmp
 
+void win32_warn_about_git_lfs_on_windows7(int exit_code, const char *argv0);
+#define warn_about_git_lfs_on_windows7 win32_warn_about_git_lfs_on_windows7
+
 #endif
diff --git a/git-compat-util.h b/git-compat-util.h
index 71b4d23f0386b2..50982de087fb89 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -514,6 +514,12 @@ static inline int git_offset_1st_component(const char *path)
 #define fspathncmp git_fspathncmp
 #endif
 
+#ifndef warn_about_git_lfs_on_windows7
+static inline void warn_about_git_lfs_on_windows7(int exit_code, const char *argv0)
+{
+}
+#endif
+
 #ifndef is_valid_path
 #define is_valid_path(path) 1
 #endif
diff --git a/run-command.c b/run-command.c
index 45ba5449323064..de6089d7332880 100644
--- a/run-command.c
+++ b/run-command.c
@@ -575,6 +575,7 @@ static int wait_or_whine(pid_t pid, const char *argv0, int in_signal)
 		 */
 		code += 128;
 	} else if (WIFEXITED(status)) {
+		warn_about_git_lfs_on_windows7(status, argv0);
 		code = WEXITSTATUS(status);
 	} else {
 		if (!in_signal)

From 10680be61d3bc9b239430630c412064addaf3516 Mon Sep 17 00:00:00 2001
From: Derrick Stolee <stolee@gmail.com>
Date: Tue, 17 Sep 2024 14:53:52 -0400
Subject: [PATCH 137/259] repack: test --full-name-hash option

The new '--full-name-hash' option for 'git repack' is a simple
pass-through to the underlying 'git pack-objects' subcommand. However,
this subcommand may have other options and a temporary filename as part
of the subcommand execution that may not be predictable or could change
over time.

The existing test_subcommand method requires an exact list of arguments
for the subcommand. This is too rigid for our needs here, so create a
new method, test_subcommand_flex. Use it to check that the
--full-name-hash option is passing through.

Signed-off-by: Derrick Stolee <stolee@gmail.com>
---
 t/t7700-repack.sh       |  7 +++++++
 t/test-lib-functions.sh | 27 +++++++++++++++++++++++++++
 2 files changed, 34 insertions(+)

diff --git a/t/t7700-repack.sh b/t/t7700-repack.sh
index 127efe99f8cd21..1a50948a64b771 100755
--- a/t/t7700-repack.sh
+++ b/t/t7700-repack.sh
@@ -782,6 +782,13 @@ test_expect_success 'repack -ad cleans up old .tmp-* packs' '
 	test_must_be_empty tmpfiles
 '
 
+test_expect_success '--full-name-hash option passes through to pack-objects' '
+	GIT_TRACE2_EVENT="$(pwd)/full-trace.txt" \
+		git repack -a --full-name-hash &&
+	test_subcommand_flex git pack-objects --full-name-hash <full-trace.txt
+'
+
+
 test_expect_success 'setup for update-server-info' '
 	git init update-server-info &&
 	test_commit -C update-server-info message
diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh
index fde9bf54fc35fc..0d94730924a78b 100644
--- a/t/test-lib-functions.sh
+++ b/t/test-lib-functions.sh
@@ -1885,6 +1885,33 @@ test_subcommand () {
 	fi
 }
 
+
+# Check that the given subcommand was run with the given set of
+# arguments in order (but with possible extra arguments).
+#
+#	test_subcommand_flex [!] <command> <args>... < <trace>
+#
+# If the first parameter passed is !, this instead checks that
+# the given command was not called.
+#
+test_subcommand_flex () {
+	local negate=
+	if test "$1" = "!"
+	then
+		negate=t
+		shift
+	fi
+
+	local expr="$(printf '"%s".*' "$@")"
+
+	if test -n "$negate"
+	then
+		! grep "\[$expr\]"
+	else
+		grep "\[$expr\]"
+	fi
+}
+
 # Check that the given command was invoked as part of the
 # trace2-format trace on stdin.
 #

From 2d1854ff153d483217ba50d2e8521f2d305aae86 Mon Sep 17 00:00:00 2001
From: Derrick Stolee <stolee@gmail.com>
Date: Tue, 17 Sep 2024 15:24:02 -0400
Subject: [PATCH 138/259] pack-objects: add GIT_TEST_FULL_NAME_HASH

Add a new environment variable to opt-in to the --full-name-hash option
in 'git pack-objects'. This allows for extra testing of the feature
without repeating all of the test scenarios.

But this option isn't free. There are a few tests that change behavior
with the variable enabled.

First, there are a few tests that are very sensitive to certain delta
bases being picked. These are both involving the generation of thin
bundles and then counting their objects via 'git index-pack --fix-thin'
which pulls the delta base into the new packfile. For these tests,
disable the option as a decent long-term option.

Second, there are two tests in t5616-partial-clone.sh that I believe are
actually broken scenarios. While the client is set up to clone the
'promisor-server' repo via a treeless partial clone filter (tree:0),
that filter does not translate to the 'server' repo. Thus, fetching from
these repos causes the server to think that the client has all reachable
trees and blobs from the commits advertised as 'haves'. This leads the
server to providing a thin pack assuming those objects as delta bases.
Changing the name-hash algorithm presents new delta bases and thus
breaks the expectations of these tests. An alternative could be to set
up 'server' as a promisor server with the correct filter enabled. This
may also point out more issues with partial clone being set up as a
remote-based filtering mechanism and not a repository-wide setting. For
now, do the minimal change to make the test work by disabling the test
variable.

Signed-off-by: Derrick Stolee <stolee@gmail.com>
---
 builtin/pack-objects.c    |  6 ++++--
 ci/run-build-and-tests.sh |  1 +
 t/README                  |  4 ++++
 t/t5510-fetch.sh          |  7 ++++++-
 t/t5616-partial-clone.sh  | 26 ++++++++++++++++++++++++--
 t/t6020-bundle-misc.sh    |  6 +++++-
 6 files changed, 44 insertions(+), 6 deletions(-)

diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 919be27b2ac8c6..f1fba6afe37d32 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -266,7 +266,7 @@ struct configured_exclusion {
 static struct oidmap configured_exclusions;
 
 static struct oidset excluded_by_config;
-static int use_full_name_hash;
+static int use_full_name_hash = -1;
 
 static inline uint32_t pack_name_hash_fn(const char *name)
 {
@@ -4554,8 +4554,10 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
 	if (pack_to_stdout || !rev_list_all)
 		write_bitmap_index = 0;
 
-	if (write_bitmap_index && use_full_name_hash)
+	if (write_bitmap_index && use_full_name_hash > 0)
 		die(_("currently, the --full-name-hash option is incompatible with --write-bitmap-index"));
+	if (use_full_name_hash < 0)
+		use_full_name_hash = git_env_bool("GIT_TEST_FULL_NAME_HASH", 0);
 
 	if (use_delta_islands)
 		strvec_push(&rp, "--topo-order");
diff --git a/ci/run-build-and-tests.sh b/ci/run-build-and-tests.sh
index 98dda42045d3f3..5ab14535a79495 100755
--- a/ci/run-build-and-tests.sh
+++ b/ci/run-build-and-tests.sh
@@ -30,6 +30,7 @@ linux-TEST-vars)
 	export GIT_TEST_NO_WRITE_REV_INDEX=1
 	export GIT_TEST_CHECKOUT_WORKERS=2
 	export GIT_TEST_PACK_USE_BITMAP_BOUNDARY_TRAVERSAL=1
+	export GIT_TEST_FULL_NAME_HASH=1
 	;;
 linux-clang)
 	export GIT_TEST_DEFAULT_HASH=sha1
diff --git a/t/README b/t/README
index 724ee58195dfae..c0a0d7ed65e5d2 100644
--- a/t/README
+++ b/t/README
@@ -488,6 +488,10 @@ a test and then fails then the whole test run will abort. This can help to make
 sure the expected tests are executed and not silently skipped when their
 dependency breaks or is simply not present in a new environment.
 
+GIT_TEST_FULL_NAME_HASH=<boolean>, when true, sets the default name-hash
+function in 'git pack-objects' to be the one used by the --full-name-hash
+option.
+
 Naming Tests
 ------------
 
diff --git a/t/t5510-fetch.sh b/t/t5510-fetch.sh
index 3b3991ab8678a5..bb4bb04ba2d41e 100755
--- a/t/t5510-fetch.sh
+++ b/t/t5510-fetch.sh
@@ -1061,7 +1061,12 @@ test_expect_success 'all boundary commits are excluded' '
 	test_tick &&
 	git merge otherside &&
 	ad=$(git log --no-walk --format=%ad HEAD) &&
-	git bundle create twoside-boundary.bdl main --since="$ad" &&
+
+	# If the --full-name-hash function is used here, then no delta
+	# pair is found and the bundle does not expand to three objects
+	# when fixing the thin object.
+	GIT_TEST_FULL_NAME_HASH=0 \
+		git bundle create twoside-boundary.bdl main --since="$ad" &&
 	test_bundle_object_count --thin twoside-boundary.bdl 3
 '
 
diff --git a/t/t5616-partial-clone.sh b/t/t5616-partial-clone.sh
index 2da7291e37997a..436f99adbb2605 100755
--- a/t/t5616-partial-clone.sh
+++ b/t/t5616-partial-clone.sh
@@ -515,7 +515,18 @@ test_expect_success 'fetch lazy-fetches only to resolve deltas' '
 	# Exercise to make sure it works. Git will not fetch anything from the
 	# promisor remote other than for the big tree (because it needs to
 	# resolve the delta).
-	GIT_TRACE_PACKET="$(pwd)/trace" git -C client \
+	#
+	# TODO: the --full-name-hash option is disabled here, since this test
+	# is fundamentally broken! When GIT_TEST_FULL_NAME_HASH=1, the server
+	# recognizes delta bases in a different way and then sends a _blob_ to
+	# the client with a delta base that the client does not have! This is
+	# because the client is cloned from "promisor-server" with tree:0 but
+	# is now fetching from "server" withot any filter. This is violating the
+	# promise to the server that all reachable objects exist and could be
+	# used as delta bases!
+	GIT_TRACE_PACKET="$(pwd)/trace" \
+	GIT_TEST_FULL_NAME_HASH=0 \
+		git -C client \
 		fetch "file://$(pwd)/server" main &&
 
 	# Verify the assumption that the client needed to fetch the delta base
@@ -534,7 +545,18 @@ test_expect_success 'fetch lazy-fetches only to resolve deltas, protocol v2' '
 	# Exercise to make sure it works. Git will not fetch anything from the
 	# promisor remote other than for the big blob (because it needs to
 	# resolve the delta).
-	GIT_TRACE_PACKET="$(pwd)/trace" git -C client \
+	#
+	# TODO: the --full-name-hash option is disabled here, since this test
+	# is fundamentally broken! When GIT_TEST_FULL_NAME_HASH=1, the server
+	# recognizes delta bases in a different way and then sends a _blob_ to
+	# the client with a delta base that the client does not have! This is
+	# because the client is cloned from "promisor-server" with tree:0 but
+	# is now fetching from "server" withot any filter. This is violating the
+	# promise to the server that all reachable objects exist and could be
+	# used as delta bases!
+	GIT_TRACE_PACKET="$(pwd)/trace" \
+	GIT_TEST_FULL_NAME_HASH=0 \
+		git -C client \
 		fetch "file://$(pwd)/server" main &&
 
 	# Verify that protocol version 2 was used.
diff --git a/t/t6020-bundle-misc.sh b/t/t6020-bundle-misc.sh
index 34b5cd62c201d9..553a20d10e98ce 100755
--- a/t/t6020-bundle-misc.sh
+++ b/t/t6020-bundle-misc.sh
@@ -247,7 +247,11 @@ test_expect_success 'create bundle with --since option' '
 	EOF
 	test_cmp expect actual &&
 
-	git bundle create since.bdl \
+	# If the --full-name-hash option is used, then one fewer
+	# delta base is found and this counts a different number
+	# of objects after performing --fix-thin.
+	GIT_TEST_FULL_NAME_HASH=0 \
+		git bundle create since.bdl \
 		--since "Thu Apr 7 15:27:00 2005 -0700" \
 		--all &&
 

From 8f25388dcb48d6a8ae7d0f750e17d9e7fdb6c11c Mon Sep 17 00:00:00 2001
From: Derrick Stolee <stolee@gmail.com>
Date: Mon, 9 Sep 2024 07:16:37 -0400
Subject: [PATCH 139/259] git-repack: update usage to match docs

This also adds the '--full-name-hash' option introduced in the previous
change and adds newlines to the synopsis.

Signed-off-by: Derrick Stolee <stolee@gmail.com>
---
 Documentation/git-repack.txt | 4 +++-
 builtin/repack.c             | 4 +++-
 t/t0450/txt-help-mismatches  | 1 -
 3 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/Documentation/git-repack.txt b/Documentation/git-repack.txt
index c902512a9e89b0..457a793fa89b2e 100644
--- a/Documentation/git-repack.txt
+++ b/Documentation/git-repack.txt
@@ -9,7 +9,9 @@ git-repack - Pack unpacked objects in a repository
 SYNOPSIS
 --------
 [verse]
-'git repack' [-a] [-A] [-d] [-f] [-F] [-l] [-n] [-q] [-b] [-m] [--window=<n>] [--depth=<n>] [--threads=<n>] [--keep-pack=<pack-name>] [--write-midx]
+'git repack' [-a] [-A] [-d] [-f] [-F] [-l] [-n] [-q] [-b] [-m]
+	[--window=<n>] [--depth=<n>] [--threads=<n>] [--keep-pack=<pack-name>]
+	[--write-midx] [--full-name-hash]
 
 DESCRIPTION
 -----------
diff --git a/builtin/repack.c b/builtin/repack.c
index 3977ed003147ad..5ffec610d5bebb 100644
--- a/builtin/repack.c
+++ b/builtin/repack.c
@@ -38,7 +38,9 @@ static int run_update_server_info = 1;
 static char *packdir, *packtmp_name, *packtmp;
 
 static const char *const git_repack_usage[] = {
-	N_("git repack [<options>]"),
+	N_("git repack [-a] [-A] [-d] [-f] [-F] [-l] [-n] [-q] [-b] [-m]\n"
+	   "[--window=<n>] [--depth=<n>] [--threads=<n>] [--keep-pack=<pack-name>]\n"
+	   "[--write-midx] [--full-name-hash]"),
 	NULL
 };
 
diff --git a/t/t0450/txt-help-mismatches b/t/t0450/txt-help-mismatches
index 28003f18c924bb..c4a15fd0cb885a 100644
--- a/t/t0450/txt-help-mismatches
+++ b/t/t0450/txt-help-mismatches
@@ -45,7 +45,6 @@ rebase
 remote
 remote-ext
 remote-fd
-repack
 reset
 restore
 rev-parse

From d2791c1113605235a8fcf3b5f207bd054c55008e Mon Sep 17 00:00:00 2001
From: Derrick Stolee <stolee@gmail.com>
Date: Wed, 28 Aug 2024 12:07:42 -0400
Subject: [PATCH 140/259] p5313: add size comparison test

As custom options are added to 'git pack-objects' and 'git repack' to
adjust how compression is done, use this new performance test script to
demonstrate their effectiveness in performance and size.

The recently-added --full-name-hash option swaps the default name-hash
algorithm with one that attempts to uniformly distribute the hashes
based on the full path name instead of the last 16 characters.

This has a dramatic effect on full repacks for repositories with many
versions of most paths. It can have a negative impact on cases such as
pushing a single change.

This can be seen by running pt5313 on the open source fluentui
repository [1]. Most commits will have this kind of output for the thin
and big pack cases, though certain commits (such as [2]) will have
problematic thin pack size for other reasons.

[1] https://github.com/microsoft/fluentui
[2] a637a06df05360ce5ff21420803f64608226a875

Checked out at the parent of [2], I see the following statistics:

Test                                           this tree
------------------------------------------------------------------
5313.2: thin pack                              0.02(0.01+0.01)
5313.3: thin pack size                                    1.1K
5313.4: thin pack with --full-name-hash        0.02(0.01+0.00)
5313.5: thin pack size with --full-name-hash              3.0K
5313.6: big pack                               1.65(3.35+0.24)
5313.7: big pack size                                    58.0M
5313.8: big pack with --full-name-hash         1.53(2.52+0.18)
5313.9: big pack size with --full-name-hash              57.6M
5313.10: repack                                176.52(706.60+3.53)
5313.11: repack size                                    446.7K
5313.12: repack with --full-name-hash          37.47(134.18+3.06)
5313.13: repack size with --full-name-hash              183.1K

Note that this demonstrates a 3x size _increase_ in the case that
simulates a small "git push". The size change is neutral on the case of
pushing the difference between HEAD and HEAD~1000.

However, the full repack case is both faster and more efficient.

Signed-off-by: Derrick Stolee <stolee@gmail.com>
---
 t/perf/p5313-pack-objects.sh | 73 ++++++++++++++++++++++++++++++++++++
 1 file changed, 73 insertions(+)
 create mode 100755 t/perf/p5313-pack-objects.sh

diff --git a/t/perf/p5313-pack-objects.sh b/t/perf/p5313-pack-objects.sh
new file mode 100755
index 00000000000000..bf6f0d69e48373
--- /dev/null
+++ b/t/perf/p5313-pack-objects.sh
@@ -0,0 +1,73 @@
+#!/bin/sh
+
+test_description='Tests pack performance using bitmaps'
+. ./perf-lib.sh
+
+GIT_TEST_PASSING_SANITIZE_LEAK=0
+export GIT_TEST_PASSING_SANITIZE_LEAK
+
+test_perf_large_repo
+
+test_expect_success 'create rev input' '
+	cat >in-thin <<-EOF &&
+	$(git rev-parse HEAD)
+	^$(git rev-parse HEAD~1)
+	EOF
+
+	cat >in-big <<-EOF
+	$(git rev-parse HEAD)
+	^$(git rev-parse HEAD~1000)
+	EOF
+'
+
+test_perf 'thin pack' '
+	git pack-objects --thin --stdout --revs --sparse  <in-thin >out
+'
+
+test_size 'thin pack size' '
+	test_file_size out
+'
+
+test_perf 'thin pack with --full-name-hash' '
+	git pack-objects --thin --stdout --revs --sparse --full-name-hash <in-thin >out
+'
+
+test_size 'thin pack size with --full-name-hash' '
+	test_file_size out
+'
+
+test_perf 'big pack' '
+	git pack-objects --stdout --revs --sparse  <in-big >out
+'
+
+test_size 'big pack size' '
+	test_file_size out
+'
+
+test_perf 'big pack with --full-name-hash' '
+	git pack-objects --stdout --revs --sparse --full-name-hash <in-big >out
+'
+
+test_size 'big pack size with --full-name-hash' '
+	test_file_size out
+'
+
+test_perf 'repack' '
+	git repack -adf
+'
+
+test_size 'repack size' '
+	pack=$(ls .git/objects/pack/pack-*.pack) &&
+	test_file_size "$pack"
+'
+
+test_perf 'repack with --full-name-hash' '
+	git repack -adf --full-name-hash
+'
+
+test_size 'repack size with --full-name-hash' '
+	pack=$(ls .git/objects/pack/pack-*.pack) &&
+	test_file_size "$pack"
+'
+
+test_done

From 5f29863da0185da046a1edf93b8488891825707c Mon Sep 17 00:00:00 2001
From: Derrick Stolee <stolee@gmail.com>
Date: Sun, 8 Sep 2024 21:04:52 -0400
Subject: [PATCH 141/259] test-tool: add helper for name-hash values

Add a new test-tool helper, name-hash, to output the value of the
name-hash algorithms for the input list of strings, one per line.

Since the name-hash values can be stored in the .bitmap files, it is
important that these hash functions do not change across Git versions.
Add a simple test to t5310-pack-bitmaps.sh to provide some testing of
the current values. Due to how these functions are implemented, it would
be difficult to change them without disturbing these values.

Create a performance test that uses test_size to demonstrate how
collisions occur for these hash algorithms. This test helps inform
someone as to the behavior of the name-hash algorithms for their repo
based on the paths at HEAD.

My copy of the Git repository shows modest statistics around the
collisions of the default name-hash algorithm:

Test                                              this tree
-----------------------------------------------------------------
5314.1: paths at head                                        4.5K
5314.2: number of distinct name-hashes                       4.1K
5314.3: number of distinct full-name-hashes                  4.5K
5314.4: maximum multiplicity of name-hashes                    13
5314.5: maximum multiplicity of fullname-hashes                 1

Here, the maximum collision multiplicity is 13, but around 10% of paths
have a collision with another path.

In a more interesting example, the microsoft/fluentui [1] repo had these
statistics at time of committing:

Test                                              this tree
-----------------------------------------------------------------
5314.1: paths at head                                       19.6K
5314.2: number of distinct name-hashes                       8.2K
5314.3: number of distinct full-name-hashes                 19.6K
5314.4: maximum multiplicity of name-hashes                   279
5314.5: maximum multiplicity of fullname-hashes                 1

[1] https://github.com/microsoft/fluentui

That demonstrates that of the nearly twenty thousand path names, they
are assigned around eight thousand distinct values. 279 paths are
assigned to a single value, leading the packing algorithm to sort
objects from those paths together, by size.

In this repository, no collisions occur for the full-name-hash
algorithm.

In a more extreme example, an internal monorepo had a much worse
collision rate:

Test                                              this tree
-----------------------------------------------------------------
5314.1: paths at head                                      221.6K
5314.2: number of distinct name-hashes                      72.0K
5314.3: number of distinct full-name-hashes                221.6K
5314.4: maximum multiplicity of name-hashes                 14.4K
5314.5: maximum multiplicity of fullname-hashes                 2

Even in this repository with many more paths at HEAD, the collision rate
was low and the maximum number of paths being grouped into a single
bucket by the full-path-name algorithm was two.

Signed-off-by: Derrick Stolee <stolee@gmail.com>
---
 Makefile                  |  1 +
 t/helper/test-name-hash.c | 24 +++++++++++++++++++++++
 t/helper/test-tool.c      |  1 +
 t/helper/test-tool.h      |  1 +
 t/perf/p5314-name-hash.sh | 41 +++++++++++++++++++++++++++++++++++++++
 t/t5310-pack-bitmaps.sh   | 26 +++++++++++++++++++++++++
 6 files changed, 94 insertions(+)
 create mode 100644 t/helper/test-name-hash.c
 create mode 100755 t/perf/p5314-name-hash.sh

diff --git a/Makefile b/Makefile
index d6479092a0b8df..4d99bfb1cc84e0 100644
--- a/Makefile
+++ b/Makefile
@@ -809,6 +809,7 @@ TEST_BUILTINS_OBJS += test-match-trees.o
 TEST_BUILTINS_OBJS += test-mergesort.o
 TEST_BUILTINS_OBJS += test-mktemp.o
 TEST_BUILTINS_OBJS += test-oid-array.o
+TEST_BUILTINS_OBJS += test-name-hash.o
 TEST_BUILTINS_OBJS += test-online-cpus.o
 TEST_BUILTINS_OBJS += test-pack-mtimes.o
 TEST_BUILTINS_OBJS += test-parse-options.o
diff --git a/t/helper/test-name-hash.c b/t/helper/test-name-hash.c
new file mode 100644
index 00000000000000..e4ecd159b76400
--- /dev/null
+++ b/t/helper/test-name-hash.c
@@ -0,0 +1,24 @@
+/*
+ * test-name-hash.c: Read a list of paths over stdin and report on their
+ * name-hash and full name-hash.
+ */
+
+#include "test-tool.h"
+#include "git-compat-util.h"
+#include "pack-objects.h"
+#include "strbuf.h"
+
+int cmd__name_hash(int argc UNUSED, const char **argv UNUSED)
+{
+	struct strbuf line = STRBUF_INIT;
+
+	while (!strbuf_getline(&line, stdin)) {
+		uint32_t name_hash = pack_name_hash(line.buf);
+		uint32_t full_hash = pack_full_name_hash(line.buf);
+
+		printf("%10"PRIu32"\t%10"PRIu32"\t%s\n", name_hash, full_hash, line.buf);
+	}
+
+	strbuf_release(&line);
+	return 0;
+}
diff --git a/t/helper/test-tool.c b/t/helper/test-tool.c
index da3e69128a976a..5f7ed5f57d63d2 100644
--- a/t/helper/test-tool.c
+++ b/t/helper/test-tool.c
@@ -43,6 +43,7 @@ static struct test_cmd cmds[] = {
 	{ "match-trees", cmd__match_trees },
 	{ "mergesort", cmd__mergesort },
 	{ "mktemp", cmd__mktemp },
+	{ "name-hash", cmd__name_hash },
 	{ "oid-array", cmd__oid_array },
 	{ "online-cpus", cmd__online_cpus },
 	{ "pack-mtimes", cmd__pack_mtimes },
diff --git a/t/helper/test-tool.h b/t/helper/test-tool.h
index 642a34578c0047..858361531bba25 100644
--- a/t/helper/test-tool.h
+++ b/t/helper/test-tool.h
@@ -37,6 +37,7 @@ int cmd__lazy_init_name_hash(int argc, const char **argv);
 int cmd__match_trees(int argc, const char **argv);
 int cmd__mergesort(int argc, const char **argv);
 int cmd__mktemp(int argc, const char **argv);
+int cmd__name_hash(int argc, const char **argv);
 int cmd__online_cpus(int argc, const char **argv);
 int cmd__pack_mtimes(int argc, const char **argv);
 int cmd__parse_options(int argc, const char **argv);
diff --git a/t/perf/p5314-name-hash.sh b/t/perf/p5314-name-hash.sh
new file mode 100755
index 00000000000000..9fe26612facc1d
--- /dev/null
+++ b/t/perf/p5314-name-hash.sh
@@ -0,0 +1,41 @@
+#!/bin/sh
+
+test_description='Tests pack performance using bitmaps'
+. ./perf-lib.sh
+
+GIT_TEST_PASSING_SANITIZE_LEAK=0
+export GIT_TEST_PASSING_SANITIZE_LEAK
+
+test_perf_large_repo
+
+test_size 'paths at head' '
+	git ls-tree -r --name-only HEAD >path-list &&
+	wc -l <path-list
+'
+
+test_size 'number of distinct name-hashes' '
+	cat path-list | test-tool name-hash >name-hashes &&
+	cat name-hashes | awk "{ print \$1; }" | sort -n | uniq -c >name-hash-count &&
+	wc -l <name-hash-count
+'
+
+test_size 'number of distinct full-name-hashes' '
+	cat name-hashes | awk "{ print \$2; }" | sort -n | uniq -c >full-name-hash-count &&
+	wc -l <full-name-hash-count
+'
+
+test_size 'maximum multiplicity of name-hashes' '
+	cat name-hash-count | \
+		sort -nr | \
+		head -n 1 | \
+		awk "{ print \$1; }"
+'
+
+test_size 'maximum multiplicity of fullname-hashes' '
+	cat full-name-hash-count | \
+		sort -nr | \
+		head -n 1 | \
+		awk "{ print \$1; }"
+'
+
+test_done
diff --git a/t/t5310-pack-bitmaps.sh b/t/t5310-pack-bitmaps.sh
index d7fd71360e17bd..5568500d3fa48d 100755
--- a/t/t5310-pack-bitmaps.sh
+++ b/t/t5310-pack-bitmaps.sh
@@ -30,6 +30,32 @@ has_any () {
 	grep -Ff "$1" "$2"
 }
 
+# Since name-hash values are stored in the .bitmap files, add a test
+# that checks that the name-hash calculations are stable across versions.
+# Not exhaustive, but these hashing algorithms would be hard to change
+# without causing deviations here.
+test_expect_success 'name-hash value stability' '
+	cat >names <<-\EOF &&
+	first
+	second
+	third
+	one-long-enough-for-collisions
+	two-long-enough-for-collisions
+	EOF
+
+	test-tool name-hash <names >out &&
+
+	cat >expect <<-\EOF &&
+	2582249472	3109209818	first
+	2289942528	3781118409	second
+	2300837888	3028707182	third
+	2544516325	3241327563	one-long-enough-for-collisions
+	2544516325	4207880830	two-long-enough-for-collisions
+	EOF
+
+	test_cmp expect out
+'
+
 test_bitmap_cases () {
 	writeLookupTable=false
 	for i in "$@"

From d020fb460be72370b5bcbebdd585b1250745a683 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 24 Sep 2024 10:06:25 +0200
Subject: [PATCH 142/259] repack/pack-objects: mark `--full-name-hash` as
 experimental

This option is still under discussion on the Git mailing list.

We still would like to have some real-world data, and the best way to
get it is to get a Git for Windows release into users' hands so that
they can test it.

Nevertheless, without the official blessing of the Git maintainer, this
optionis experimental, and we need to be clear about that.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 builtin/pack-objects.c | 2 +-
 builtin/repack.c       | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index f1fba6afe37d32..e93ec82756238a 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -4406,7 +4406,7 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
 				N_("protocol"),
 				N_("exclude any configured uploadpack.blobpackfileuri with this protocol")),
 		OPT_BOOL(0, "full-name-hash", &use_full_name_hash,
-			 N_("optimize delta compression across identical path names over time")),
+			 N_("(EXPERIMENTAL!) optimize delta compression across identical path names over time")),
 		OPT_END(),
 	};
 
diff --git a/builtin/repack.c b/builtin/repack.c
index 5ffec610d5bebb..c113eb378575e8 100644
--- a/builtin/repack.c
+++ b/builtin/repack.c
@@ -1163,7 +1163,7 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
 		OPT_BOOL('F', NULL, &po_args.no_reuse_object,
 				N_("pass --no-reuse-object to git-pack-objects")),
 		OPT_BOOL(0, "full-name-hash", &po_args.full_name_hash,
-				N_("pass --full-name-hash to git-pack-objects")),
+				N_("(EXPERIMENTAL!) pass --full-name-hash to git-pack-objects")),
 		OPT_NEGBIT('n', NULL, &run_update_server_info,
 				N_("do not run git-update-server-info"), 1),
 		OPT__QUIET(&po_args.quiet, N_("be quiet")),

From 20bfc1f7057cbd9b9d522b201415d0dfe43dbccb Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sat, 6 Jul 2013 02:09:35 +0200
Subject: [PATCH 143/259] Win32: make FILETIME conversion functions public

We will use them in the upcoming "FSCache" patches (to accelerate
sequential lstat() calls).

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 18 ------------------
 compat/mingw.h | 18 ++++++++++++++++++
 2 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index c63f6b3a9bd727..1345e3ea2c5ff2 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -788,24 +788,6 @@ int mingw_chmod(const char *filename, int mode)
 	return _wchmod(wfilename, mode);
 }
 
-/*
- * The unit of FILETIME is 100-nanoseconds since January 1, 1601, UTC.
- * Returns the 100-nanoseconds ("hekto nanoseconds") since the epoch.
- */
-static inline long long filetime_to_hnsec(const FILETIME *ft)
-{
-	long long winTime = ((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime;
-	/* Windows to Unix Epoch conversion */
-	return winTime - 116444736000000000LL;
-}
-
-static inline void filetime_to_timespec(const FILETIME *ft, struct timespec *ts)
-{
-	long long hnsec = filetime_to_hnsec(ft);
-	ts->tv_sec = (time_t)(hnsec / 10000000);
-	ts->tv_nsec = (hnsec % 10000000) * 100;
-}
-
 /**
  * Verifies that safe_create_leading_directories() would succeed.
  */
diff --git a/compat/mingw.h b/compat/mingw.h
index 61f98ec39cca2b..f59f7524690cf0 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -356,6 +356,17 @@ static inline int getrlimit(int resource, struct rlimit *rlp)
 	return 0;
 }
 
+/*
+ * The unit of FILETIME is 100-nanoseconds since January 1, 1601, UTC.
+ * Returns the 100-nanoseconds ("hekto nanoseconds") since the epoch.
+ */
+static inline long long filetime_to_hnsec(const FILETIME *ft)
+{
+	long long winTime = ((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime;
+	/* Windows to Unix Epoch conversion */
+	return winTime - 116444736000000000LL;
+}
+
 /*
  * Use mingw specific stat()/lstat()/fstat() implementations on Windows,
  * including our own struct stat with 64 bit st_size and nanosecond-precision
@@ -372,6 +383,13 @@ struct timespec {
 #endif
 #endif
 
+static inline void filetime_to_timespec(const FILETIME *ft, struct timespec *ts)
+{
+	long long hnsec = filetime_to_hnsec(ft);
+	ts->tv_sec = (time_t)(hnsec / 10000000);
+	ts->tv_nsec = (hnsec % 10000000) * 100;
+}
+
 struct mingw_stat {
     _dev_t st_dev;
     _ino_t st_ino;

From 58f9dfe80302d274cd0b23469e56649dcfdb2f53 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sun, 8 Sep 2013 14:17:31 +0200
Subject: [PATCH 144/259] Win32: dirent.c: Move opendir down

Move opendir down in preparation for the next patch.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/win32/dirent.c | 68 +++++++++++++++++++++----------------------
 1 file changed, 34 insertions(+), 34 deletions(-)

diff --git a/compat/win32/dirent.c b/compat/win32/dirent.c
index 52420ec7d4dad7..2603a0fa39f45a 100644
--- a/compat/win32/dirent.c
+++ b/compat/win32/dirent.c
@@ -18,40 +18,6 @@ static inline void finddata2dirent(struct dirent *ent, WIN32_FIND_DATAW *fdata)
 		ent->d_type = DT_REG;
 }
 
-DIR *opendir(const char *name)
-{
-	wchar_t pattern[MAX_PATH + 2]; /* + 2 for '/' '*' */
-	WIN32_FIND_DATAW fdata;
-	HANDLE h;
-	int len;
-	DIR *dir;
-
-	/* convert name to UTF-16 and check length < MAX_PATH */
-	if ((len = xutftowcs_path(pattern, name)) < 0)
-		return NULL;
-
-	/* append optional '/' and wildcard '*' */
-	if (len && !is_dir_sep(pattern[len - 1]))
-		pattern[len++] = '/';
-	pattern[len++] = '*';
-	pattern[len] = 0;
-
-	/* open find handle */
-	h = FindFirstFileW(pattern, &fdata);
-	if (h == INVALID_HANDLE_VALUE) {
-		DWORD err = GetLastError();
-		errno = (err == ERROR_DIRECTORY) ? ENOTDIR : err_win_to_posix(err);
-		return NULL;
-	}
-
-	/* initialize DIR structure and copy first dir entry */
-	dir = xmalloc(sizeof(DIR));
-	dir->dd_handle = h;
-	dir->dd_stat = 0;
-	finddata2dirent(&dir->dd_dir, &fdata);
-	return dir;
-}
-
 struct dirent *readdir(DIR *dir)
 {
 	if (!dir) {
@@ -90,3 +56,37 @@ int closedir(DIR *dir)
 	free(dir);
 	return 0;
 }
+
+DIR *opendir(const char *name)
+{
+	wchar_t pattern[MAX_PATH + 2]; /* + 2 for '/' '*' */
+	WIN32_FIND_DATAW fdata;
+	HANDLE h;
+	int len;
+	DIR *dir;
+
+	/* convert name to UTF-16 and check length < MAX_PATH */
+	if ((len = xutftowcs_path(pattern, name)) < 0)
+		return NULL;
+
+	/* append optional '/' and wildcard '*' */
+	if (len && !is_dir_sep(pattern[len - 1]))
+		pattern[len++] = '/';
+	pattern[len++] = '*';
+	pattern[len] = 0;
+
+	/* open find handle */
+	h = FindFirstFileW(pattern, &fdata);
+	if (h == INVALID_HANDLE_VALUE) {
+		DWORD err = GetLastError();
+		errno = (err == ERROR_DIRECTORY) ? ENOTDIR : err_win_to_posix(err);
+		return NULL;
+	}
+
+	/* initialize DIR structure and copy first dir entry */
+	dir = xmalloc(sizeof(DIR));
+	dir->dd_handle = h;
+	dir->dd_stat = 0;
+	finddata2dirent(&dir->dd_dir, &fdata);
+	return dir;
+}

From 071ce8694513d386bb7ef967b3da9fd44d3163d0 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sun, 8 Sep 2013 14:18:40 +0200
Subject: [PATCH 145/259] mingw: make the dirent implementation pluggable

Emulating the POSIX `dirent` API on Windows via
`FindFirstFile()`/`FindNextFile()` is pretty staightforward, however,
most of the information provided in the `WIN32_FIND_DATA` structure is
thrown away in the process. A more sophisticated implementation may
cache this data, e.g. for later reuse in calls to `lstat()`.

Make the `dirent` implementation pluggable so that it can be switched at
runtime, e.g. based on a config option.

Define a base DIR structure with pointers to `readdir()`/`closedir()`
that match the `opendir()` implementation (similar to vtable pointers in
Object-Oriented Programming). Define `readdir()`/`closedir()` so that
they call the function pointers in the `DIR` structure. This allows to
choose the `opendir()` implementation on a call-by-call basis.

Make the fixed-size `dirent.d_name` buffer a flex array, as `d_name` may
be implementation specific (e.g. a caching implementation may allocate a
`struct dirent` with _just_ the size needed to hold the `d_name` in
question).

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/win32/dirent.c | 30 +++++++++++++++++++-----------
 compat/win32/dirent.h | 26 +++++++++++++++++++-------
 2 files changed, 38 insertions(+), 18 deletions(-)

diff --git a/compat/win32/dirent.c b/compat/win32/dirent.c
index 2603a0fa39f45a..139d2ba3c4da34 100644
--- a/compat/win32/dirent.c
+++ b/compat/win32/dirent.c
@@ -1,15 +1,21 @@
 #include "../../git-compat-util.h"
 
-struct DIR {
-	struct dirent dd_dir; /* includes d_type */
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wpedantic"
+typedef struct dirent_DIR {
+	struct DIR base_dir;  /* extend base struct DIR */
 	HANDLE dd_handle;     /* FindFirstFile handle */
 	int dd_stat;          /* 0-based index */
-};
+	struct dirent dd_dir; /* includes d_type */
+} dirent_DIR;
+#pragma GCC diagnostic pop
+
+DIR *(*opendir)(const char *dirname) = dirent_opendir;
 
 static inline void finddata2dirent(struct dirent *ent, WIN32_FIND_DATAW *fdata)
 {
-	/* convert UTF-16 name to UTF-8 */
-	xwcstoutf(ent->d_name, fdata->cFileName, sizeof(ent->d_name));
+	/* convert UTF-16 name to UTF-8 (d_name points to dirent_DIR.dd_name) */
+	xwcstoutf(ent->d_name, fdata->cFileName, MAX_PATH * 3);
 
 	/* Set file type, based on WIN32_FIND_DATA */
 	if (fdata->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
@@ -18,7 +24,7 @@ static inline void finddata2dirent(struct dirent *ent, WIN32_FIND_DATAW *fdata)
 		ent->d_type = DT_REG;
 }
 
-struct dirent *readdir(DIR *dir)
+static struct dirent *dirent_readdir(dirent_DIR *dir)
 {
 	if (!dir) {
 		errno = EBADF; /* No set_errno for mingw */
@@ -45,7 +51,7 @@ struct dirent *readdir(DIR *dir)
 	return &dir->dd_dir;
 }
 
-int closedir(DIR *dir)
+static int dirent_closedir(dirent_DIR *dir)
 {
 	if (!dir) {
 		errno = EBADF;
@@ -57,13 +63,13 @@ int closedir(DIR *dir)
 	return 0;
 }
 
-DIR *opendir(const char *name)
+DIR *dirent_opendir(const char *name)
 {
 	wchar_t pattern[MAX_PATH + 2]; /* + 2 for '/' '*' */
 	WIN32_FIND_DATAW fdata;
 	HANDLE h;
 	int len;
-	DIR *dir;
+	dirent_DIR *dir;
 
 	/* convert name to UTF-16 and check length < MAX_PATH */
 	if ((len = xutftowcs_path(pattern, name)) < 0)
@@ -84,9 +90,11 @@ DIR *opendir(const char *name)
 	}
 
 	/* initialize DIR structure and copy first dir entry */
-	dir = xmalloc(sizeof(DIR));
+	dir = xmalloc(sizeof(dirent_DIR) + MAX_PATH);
+	dir->base_dir.preaddir = (struct dirent *(*)(DIR *dir)) dirent_readdir;
+	dir->base_dir.pclosedir = (int (*)(DIR *dir)) dirent_closedir;
 	dir->dd_handle = h;
 	dir->dd_stat = 0;
 	finddata2dirent(&dir->dd_dir, &fdata);
-	return dir;
+	return (DIR*) dir;
 }
diff --git a/compat/win32/dirent.h b/compat/win32/dirent.h
index 058207e4bfed62..e0e0e1700f64d1 100644
--- a/compat/win32/dirent.h
+++ b/compat/win32/dirent.h
@@ -1,20 +1,32 @@
 #ifndef DIRENT_H
 #define DIRENT_H
 
-typedef struct DIR DIR;
-
 #define DT_UNKNOWN 0
 #define DT_DIR     1
 #define DT_REG     2
 #define DT_LNK     3
 
 struct dirent {
-	unsigned char d_type;      /* file type to prevent lstat after readdir */
-	char d_name[MAX_PATH * 3]; /* file name (* 3 for UTF-8 conversion) */
+	unsigned char d_type; /* file type to prevent lstat after readdir */
+	char d_name[FLEX_ARRAY]; /* file name */
 };
 
-DIR *opendir(const char *dirname);
-struct dirent *readdir(DIR *dir);
-int closedir(DIR *dir);
+/*
+ * Base DIR structure, contains pointers to readdir/closedir implementations so
+ * that opendir may choose a concrete implementation on a call-by-call basis.
+ */
+typedef struct DIR {
+	struct dirent *(*preaddir)(struct DIR *dir);
+	int (*pclosedir)(struct DIR *dir);
+} DIR;
+
+/* default dirent implementation */
+extern DIR *dirent_opendir(const char *dirname);
+
+/* current dirent implementation */
+extern DIR *(*opendir)(const char *dirname);
+
+#define readdir(dir) (dir->preaddir(dir))
+#define closedir(dir) (dir->pclosedir(dir))
 
 #endif /* DIRENT_H */

From 1913d2b9c51cf92f1e6e6b540d8d0a4d7b1898a5 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sun, 8 Sep 2013 14:21:30 +0200
Subject: [PATCH 146/259] Win32: make the lstat implementation pluggable

Emulating the POSIX lstat API on Windows via GetFileAttributes[Ex] is quite
slow. Windows operating system APIs seem to be much better at scanning the
status of entire directories than checking single files. A caching
implementation may improve performance by bulk-reading entire directories
or reusing data obtained via opendir / readdir.

Make the lstat implementation pluggable so that it can be switched at
runtime, e.g. based on a config option.

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 2 ++
 compat/mingw.h | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 1345e3ea2c5ff2..a68141b17cf558 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -927,6 +927,8 @@ static int do_stat_internal(int follow, const char *file_name, struct stat *buf)
 	return do_lstat(follow, alt_name, buf);
 }
 
+int (*lstat)(const char *file_name, struct stat *buf) = mingw_lstat;
+
 static int get_file_info_by_handle(HANDLE hnd, struct stat *buf)
 {
 	BY_HANDLE_FILE_INFORMATION fdata;
diff --git a/compat/mingw.h b/compat/mingw.h
index f59f7524690cf0..f982cb98bf9385 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -422,7 +422,7 @@ int mingw_fstat(int fd, struct stat *buf);
 #ifdef lstat
 #undef lstat
 #endif
-#define lstat mingw_lstat
+extern int (*lstat)(const char *file_name, struct stat *buf);
 
 
 int mingw_utime(const char *file_name, const struct utimbuf *times);

From 6d42e40f5b9e1f6f294ac48d283b8aeb34c61ef3 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sun, 8 Sep 2013 14:23:27 +0200
Subject: [PATCH 147/259] mingw: add infrastructure for read-only file system
 level caches

Add a macro to mark code sections that only read from the file system,
along with a config option and documentation.

This facilitates implementation of relatively simple file system level
caches without the need to synchronize with the file system.

Enable read-only sections for 'git status' and preload_index.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 Documentation/config/core.txt |  6 ++++++
 builtin/commit.c              |  1 +
 compat/mingw.c                |  6 ++++++
 compat/mingw.h                |  2 ++
 git-compat-util.h             | 15 +++++++++++++++
 preload-index.c               |  3 +++
 6 files changed, 33 insertions(+)

diff --git a/Documentation/config/core.txt b/Documentation/config/core.txt
index 60ca9f2b686106..b894c7e9cc8a57 100644
--- a/Documentation/config/core.txt
+++ b/Documentation/config/core.txt
@@ -685,6 +685,12 @@ relatively high IO latencies.  When enabled, Git will do the
 index comparison to the filesystem data in parallel, allowing
 overlapping IO's.  Defaults to true.
 
+core.fscache::
+	Enable additional caching of file system data for some operations.
++
+Git for Windows uses this to bulk-read and cache lstat data of entire
+directories (instead of doing lstat file by file).
+
 core.unsetenvvars::
 	Windows-only: comma-separated list of environment variables'
 	names that need to be unset before spawning any other process.
diff --git a/builtin/commit.c b/builtin/commit.c
index 66427ba82d5b9b..794ea24d9ab9a0 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -1568,6 +1568,7 @@ int cmd_status(int argc, const char **argv, const char *prefix)
 		       PATHSPEC_PREFER_FULL,
 		       prefix, argv);
 
+	enable_fscache(1);
 	if (status_format != STATUS_FORMAT_PORCELAIN &&
 	    status_format != STATUS_FORMAT_PORCELAIN_V2)
 		progress_flag = REFRESH_PROGRESS;
diff --git a/compat/mingw.c b/compat/mingw.c
index a68141b17cf558..ca8b116190b3af 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -244,6 +244,7 @@ enum hide_dotfiles_type {
 static int core_restrict_inherited_handles = -1;
 static enum hide_dotfiles_type hide_dotfiles = HIDE_DOTFILES_DOTGITONLY;
 static char *unset_environment_variables;
+int core_fscache;
 
 int mingw_core_config(const char *var, const char *value,
 		      const struct config_context *ctx, void *cb)
@@ -256,6 +257,11 @@ int mingw_core_config(const char *var, const char *value,
 		return 0;
 	}
 
+	if (!strcmp(var, "core.fscache")) {
+		core_fscache = git_config_bool(var, value);
+		return 0;
+	}
+
 	if (!strcmp(var, "core.unsetenvvars")) {
 		if (!value)
 			return config_error_nonbool(var);
diff --git a/compat/mingw.h b/compat/mingw.h
index f982cb98bf9385..946ff707327b4e 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -11,6 +11,8 @@ typedef _sigset_t sigset_t;
 #undef _POSIX_THREAD_SAFE_FUNCTIONS
 #endif
 
+extern int core_fscache;
+
 struct config_context;
 int mingw_core_config(const char *var, const char *value,
 		      const struct config_context *ctx, void *cb);
diff --git a/git-compat-util.h b/git-compat-util.h
index 710230d7321395..c8429efc22c7f1 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1520,6 +1520,21 @@ static inline int is_missing_file_error(int errno_)
 	return (errno_ == ENOENT || errno_ == ENOTDIR);
 }
 
+/*
+ * Enable/disable a read-only cache for file system data on platforms that
+ * support it.
+ *
+ * Implementing a live-cache is complicated and requires special platform
+ * support (inotify, ReadDirectoryChangesW...). enable_fscache shall be used
+ * to mark sections of git code that extensively read from the file system
+ * without modifying anything. Implementations can use this to cache e.g. stat
+ * data or even file content without the need to synchronize with the file
+ * system.
+ */
+#ifndef enable_fscache
+#define enable_fscache(x) /* noop */
+#endif
+
 int cmd_main(int, const char **);
 
 /*
diff --git a/preload-index.c b/preload-index.c
index 63fd35d64b141f..ec1d7b46d55fc0 100644
--- a/preload-index.c
+++ b/preload-index.c
@@ -132,6 +132,7 @@ void preload_index(struct index_state *index,
 		pthread_mutex_init(&pd.mutex, NULL);
 	}
 
+	enable_fscache(1);
 	for (i = 0; i < threads; i++) {
 		struct thread_data *p = data+i;
 		int err;
@@ -167,6 +168,8 @@ void preload_index(struct index_state *index,
 
 	trace2_data_intmax("index", NULL, "preload/sum_lstat", t2_sum_lstat);
 	trace2_region_leave("index", "preload", NULL);
+
+	enable_fscache(0);
 }
 
 int repo_read_index_preload(struct repository *repo,

From e574b79b64b96d07484495f73cc1283f7dd8c060 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Tue, 1 Oct 2013 12:51:54 +0200
Subject: [PATCH 148/259] mingw: add a cache below mingw's lstat and dirent
 implementations

Checking the work tree status is quite slow on Windows, due to slow
`lstat()` emulation (git calls `lstat()` once for each file in the
index). Windows operating system APIs seem to be much better at scanning
the status of entire directories than checking single files.

Add an `lstat()` implementation that uses a cache for lstat data. Cache
misses read the entire parent directory and add it to the cache.
Subsequent `lstat()` calls for the same directory are served directly
from the cache.

Also implement `opendir()`/`readdir()`/`closedir()` so that they create
and use directory listings in the cache.

The cache doesn't track file system changes and doesn't plug into any
modifying file APIs, so it has to be explicitly enabled for git functions
that don't modify the working copy.

Note: in an earlier version of this patch, the cache was always active and
tracked file system changes via ReadDirectoryChangesW. However, this was
much more complex and had negative impact on the performance of modifying
git commands such as 'git checkout'.

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/win32/fscache.c              | 463 ++++++++++++++++++++++++++++
 compat/win32/fscache.h              |  10 +
 config.mak.uname                    |   4 +-
 contrib/buildsystems/CMakeLists.txt |   3 +-
 git-compat-util.h                   |   2 +
 5 files changed, 479 insertions(+), 3 deletions(-)
 create mode 100644 compat/win32/fscache.c
 create mode 100644 compat/win32/fscache.h

diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
new file mode 100644
index 00000000000000..16e556274614f6
--- /dev/null
+++ b/compat/win32/fscache.c
@@ -0,0 +1,463 @@
+#include "../../git-compat-util.h"
+#include "../../hashmap.h"
+#include "../win32.h"
+#include "fscache.h"
+#include "../../dir.h"
+#include "../../abspath.h"
+
+static int initialized;
+static volatile long enabled;
+static struct hashmap map;
+static CRITICAL_SECTION mutex;
+
+/*
+ * An entry in the file system cache. Used for both entire directory listings
+ * and file entries.
+ */
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wpedantic"
+struct fsentry {
+	struct hashmap_entry ent;
+	mode_t st_mode;
+	/* Pointer to the directory listing, or NULL for the listing itself. */
+	struct fsentry *list;
+	/* Pointer to the next file entry of the list. */
+	struct fsentry *next;
+
+	union {
+		/* Reference count of the directory listing. */
+		volatile long refcnt;
+		struct {
+			/* More stat members (only used for file entries). */
+			off64_t st_size;
+			struct timespec st_atim;
+			struct timespec st_mtim;
+			struct timespec st_ctim;
+		} s;
+	} u;
+
+	/* Length of name. */
+	unsigned short len;
+	/*
+	 * Name of the entry. For directory listings: relative path of the
+	 * directory, without trailing '/' (empty for cwd()). For file entries:
+	 * name of the file. Typically points to the end of the structure if
+	 * the fsentry is allocated on the heap (see fsentry_alloc), or to a
+	 * local variable if on the stack (see fsentry_init).
+	 */
+	struct dirent dirent;
+};
+#pragma GCC diagnostic pop
+
+struct heap_fsentry {
+	union {
+		struct fsentry ent;
+		char dummy[sizeof(struct fsentry) + MAX_PATH];
+	} u;
+};
+
+/*
+ * Compares the paths of two fsentry structures for equality.
+ */
+static int fsentry_cmp(void *unused_cmp_data,
+		       const struct fsentry *fse1, const struct fsentry *fse2,
+		       void *unused_keydata)
+{
+	int res;
+	if (fse1 == fse2)
+		return 0;
+
+	/* compare the list parts first */
+	if (fse1->list != fse2->list &&
+	    (res = fsentry_cmp(NULL, fse1->list ? fse1->list : fse1,
+			       fse2->list ? fse2->list	: fse2, NULL)))
+		return res;
+
+	/* if list parts are equal, compare len and name */
+	if (fse1->len != fse2->len)
+		return fse1->len - fse2->len;
+	return fspathncmp(fse1->dirent.d_name, fse2->dirent.d_name, fse1->len);
+}
+
+/*
+ * Calculates the hash code of an fsentry structure's path.
+ */
+static unsigned int fsentry_hash(const struct fsentry *fse)
+{
+	unsigned int hash = fse->list ? fse->list->ent.hash : 0;
+	return hash ^ memihash(fse->dirent.d_name, fse->len);
+}
+
+/*
+ * Initialize an fsentry structure for use by fsentry_hash and fsentry_cmp.
+ */
+static void fsentry_init(struct fsentry *fse, struct fsentry *list,
+			 const char *name, size_t len)
+{
+	fse->list = list;
+	if (len > MAX_PATH)
+		BUG("Trying to allocate fsentry for long path '%.*s'",
+		    (int)len, name);
+	memcpy(fse->dirent.d_name, name, len);
+	fse->dirent.d_name[len] = 0;
+	fse->len = len;
+	hashmap_entry_init(&fse->ent, fsentry_hash(fse));
+}
+
+/*
+ * Allocate an fsentry structure on the heap.
+ */
+static struct fsentry *fsentry_alloc(struct fsentry *list, const char *name,
+		size_t len)
+{
+	/* overallocate fsentry and copy the name to the end */
+	struct fsentry *fse = xmalloc(sizeof(struct fsentry) + len + 1);
+	/* init the rest of the structure */
+	fsentry_init(fse, list, name, len);
+	fse->next = NULL;
+	fse->u.refcnt = 1;
+	return fse;
+}
+
+/*
+ * Add a reference to an fsentry.
+ */
+inline static void fsentry_addref(struct fsentry *fse)
+{
+	if (fse->list)
+		fse = fse->list;
+
+	InterlockedIncrement(&(fse->u.refcnt));
+}
+
+/*
+ * Release the reference to an fsentry, frees the memory if its the last ref.
+ */
+static void fsentry_release(struct fsentry *fse)
+{
+	if (fse->list)
+		fse = fse->list;
+
+	if (InterlockedDecrement(&(fse->u.refcnt)))
+		return;
+
+	while (fse) {
+		struct fsentry *next = fse->next;
+		free(fse);
+		fse = next;
+	}
+}
+
+/*
+ * Allocate and initialize an fsentry from a WIN32_FIND_DATA structure.
+ */
+static struct fsentry *fseentry_create_entry(struct fsentry *list,
+					     const WIN32_FIND_DATAW *fdata)
+{
+	char buf[MAX_PATH * 3];
+	int len;
+	struct fsentry *fse;
+	len = xwcstoutf(buf, fdata->cFileName, ARRAY_SIZE(buf));
+
+	fse = fsentry_alloc(list, buf, len);
+
+	fse->st_mode = file_attr_to_st_mode(fdata->dwFileAttributes);
+	fse->dirent.d_type = S_ISDIR(fse->st_mode) ? DT_DIR : DT_REG;
+	fse->u.s.st_size = (((off64_t) (fdata->nFileSizeHigh)) << 32)
+			| fdata->nFileSizeLow;
+	filetime_to_timespec(&(fdata->ftLastAccessTime), &(fse->u.s.st_atim));
+	filetime_to_timespec(&(fdata->ftLastWriteTime), &(fse->u.s.st_mtim));
+	filetime_to_timespec(&(fdata->ftCreationTime), &(fse->u.s.st_ctim));
+
+	return fse;
+}
+
+/*
+ * Create an fsentry-based directory listing (similar to opendir / readdir).
+ * Dir should not contain trailing '/'. Use an empty string for the current
+ * directory (not "."!).
+ */
+static struct fsentry *fsentry_create_list(const struct fsentry *dir)
+{
+	wchar_t pattern[MAX_PATH + 2]; /* + 2 for '/' '*' */
+	WIN32_FIND_DATAW fdata;
+	HANDLE h;
+	int wlen;
+	struct fsentry *list, **phead;
+	DWORD err;
+
+	/* convert name to UTF-16 and check length < MAX_PATH */
+	if ((wlen = xutftowcsn(pattern, dir->dirent.d_name, MAX_PATH,
+			       dir->len)) < 0) {
+		if (errno == ERANGE)
+			errno = ENAMETOOLONG;
+		return NULL;
+	}
+
+	/* append optional '/' and wildcard '*' */
+	if (wlen)
+		pattern[wlen++] = '/';
+	pattern[wlen++] = '*';
+	pattern[wlen] = 0;
+
+	/* open find handle */
+	h = FindFirstFileW(pattern, &fdata);
+	if (h == INVALID_HANDLE_VALUE) {
+		err = GetLastError();
+		errno = (err == ERROR_DIRECTORY) ? ENOTDIR : err_win_to_posix(err);
+		return NULL;
+	}
+
+	/* allocate object to hold directory listing */
+	list = fsentry_alloc(NULL, dir->dirent.d_name, dir->len);
+
+	/* walk directory and build linked list of fsentry structures */
+	phead = &list->next;
+	do {
+		*phead = fseentry_create_entry(list, &fdata);
+		phead = &(*phead)->next;
+	} while (FindNextFileW(h, &fdata));
+
+	/* remember result of last FindNextFile, then close find handle */
+	err = GetLastError();
+	FindClose(h);
+
+	/* return the list if we've got all the files */
+	if (err == ERROR_NO_MORE_FILES)
+		return list;
+
+	/* otherwise free the list and return error */
+	fsentry_release(list);
+	errno = err_win_to_posix(err);
+	return NULL;
+}
+
+/*
+ * Adds a directory listing to the cache.
+ */
+static void fscache_add(struct fsentry *fse)
+{
+	if (fse->list)
+		fse = fse->list;
+
+	for (; fse; fse = fse->next)
+		hashmap_add(&map, &fse->ent);
+}
+
+/*
+ * Clears the cache.
+ */
+static void fscache_clear(void)
+{
+	hashmap_clear_and_free(&map, struct fsentry, ent);
+	hashmap_init(&map, (hashmap_cmp_fn)fsentry_cmp, NULL, 0);
+}
+
+/*
+ * Checks if the cache is enabled for the given path.
+ */
+static inline int fscache_enabled(const char *path)
+{
+	return enabled > 0 && !is_absolute_path(path);
+}
+
+/*
+ * Looks up or creates a cache entry for the specified key.
+ */
+static struct fsentry *fscache_get(struct fsentry *key)
+{
+	struct fsentry *fse;
+
+	EnterCriticalSection(&mutex);
+	/* check if entry is in cache */
+	fse = hashmap_get_entry(&map, key, ent, NULL);
+	if (fse) {
+		fsentry_addref(fse);
+		LeaveCriticalSection(&mutex);
+		return fse;
+	}
+	/* if looking for a file, check if directory listing is in cache */
+	if (!fse && key->list) {
+		fse = hashmap_get_entry(&map, key->list, ent, NULL);
+		if (fse) {
+			LeaveCriticalSection(&mutex);
+			/* dir entry without file entry -> file doesn't exist */
+			errno = ENOENT;
+			return NULL;
+		}
+	}
+
+	/* create the directory listing (outside mutex!) */
+	LeaveCriticalSection(&mutex);
+	fse = fsentry_create_list(key->list ? key->list : key);
+	if (!fse)
+		return NULL;
+
+	EnterCriticalSection(&mutex);
+	/* add directory listing if it hasn't been added by some other thread */
+	if (!hashmap_get_entry(&map, key, ent, NULL))
+		fscache_add(fse);
+
+	/* lookup file entry if requested (fse already points to directory) */
+	if (key->list)
+		fse = hashmap_get_entry(&map, key, ent, NULL);
+
+	/* return entry or ENOENT */
+	if (fse)
+		fsentry_addref(fse);
+	else
+		errno = ENOENT;
+
+	LeaveCriticalSection(&mutex);
+	return fse;
+}
+
+/*
+ * Enables or disables the cache. Note that the cache is read-only, changes to
+ * the working directory are NOT reflected in the cache while enabled.
+ */
+int fscache_enable(int enable)
+{
+	int result;
+
+	if (!initialized) {
+		/* allow the cache to be disabled entirely */
+		if (!core_fscache)
+			return 0;
+
+		InitializeCriticalSection(&mutex);
+		hashmap_init(&map, (hashmap_cmp_fn) fsentry_cmp, NULL, 0);
+		initialized = 1;
+	}
+
+	result = enable ? InterlockedIncrement(&enabled)
+			: InterlockedDecrement(&enabled);
+
+	if (enable && result == 1) {
+		/* redirect opendir and lstat to the fscache implementations */
+		opendir = fscache_opendir;
+		lstat = fscache_lstat;
+	} else if (!enable && !result) {
+		/* reset opendir and lstat to the original implementations */
+		opendir = dirent_opendir;
+		lstat = mingw_lstat;
+		EnterCriticalSection(&mutex);
+		fscache_clear();
+		LeaveCriticalSection(&mutex);
+	}
+	return result;
+}
+
+/*
+ * Lstat replacement, uses the cache if enabled, otherwise redirects to
+ * mingw_lstat.
+ */
+int fscache_lstat(const char *filename, struct stat *st)
+{
+	int dirlen, base, len;
+	struct heap_fsentry key[2];
+	struct fsentry *fse;
+
+	if (!fscache_enabled(filename))
+		return mingw_lstat(filename, st);
+
+	/* split filename into path + name */
+	len = strlen(filename);
+	if (len && is_dir_sep(filename[len - 1]))
+		len--;
+	base = len;
+	while (base && !is_dir_sep(filename[base - 1]))
+		base--;
+	dirlen = base ? base - 1 : 0;
+
+	/* lookup entry for path + name in cache */
+	fsentry_init(&key[0].u.ent, NULL, filename, dirlen);
+	fsentry_init(&key[1].u.ent, &key[0].u.ent, filename + base, len - base);
+	fse = fscache_get(&key[1].u.ent);
+	if (!fse) {
+		errno = ENOENT;
+		return -1;
+	}
+
+	/* copy stat data */
+	st->st_ino = 0;
+	st->st_gid = 0;
+	st->st_uid = 0;
+	st->st_dev = 0;
+	st->st_rdev = 0;
+	st->st_nlink = 1;
+	st->st_mode = fse->st_mode;
+	st->st_size = fse->u.s.st_size;
+	st->st_atim = fse->u.s.st_atim;
+	st->st_mtim = fse->u.s.st_mtim;
+	st->st_ctim = fse->u.s.st_ctim;
+
+	/* don't forget to release fsentry */
+	fsentry_release(fse);
+	return 0;
+}
+
+typedef struct fscache_DIR {
+	struct DIR base_dir; /* extend base struct DIR */
+	struct fsentry *pfsentry;
+	struct dirent *dirent;
+} fscache_DIR;
+
+/*
+ * Readdir replacement.
+ */
+static struct dirent *fscache_readdir(DIR *base_dir)
+{
+	fscache_DIR *dir = (fscache_DIR*) base_dir;
+	struct fsentry *next = dir->pfsentry->next;
+	if (!next)
+		return NULL;
+	dir->pfsentry = next;
+	dir->dirent = &next->dirent;
+	return dir->dirent;
+}
+
+/*
+ * Closedir replacement.
+ */
+static int fscache_closedir(DIR *base_dir)
+{
+	fscache_DIR *dir = (fscache_DIR*) base_dir;
+	fsentry_release(dir->pfsentry);
+	free(dir);
+	return 0;
+}
+
+/*
+ * Opendir replacement, uses a directory listing from the cache if enabled,
+ * otherwise calls original dirent implementation.
+ */
+DIR *fscache_opendir(const char *dirname)
+{
+	struct heap_fsentry key;
+	struct fsentry *list;
+	fscache_DIR *dir;
+	int len;
+
+	if (!fscache_enabled(dirname))
+		return dirent_opendir(dirname);
+
+	/* prepare name (strip trailing '/', replace '.') */
+	len = strlen(dirname);
+	if ((len == 1 && dirname[0] == '.') ||
+	    (len && is_dir_sep(dirname[len - 1])))
+		len--;
+
+	/* get directory listing from cache */
+	fsentry_init(&key.u.ent, NULL, dirname, len);
+	list = fscache_get(&key.u.ent);
+	if (!list)
+		return NULL;
+
+	/* alloc and return DIR structure */
+	dir = (fscache_DIR*) xmalloc(sizeof(fscache_DIR));
+	dir->base_dir.preaddir = fscache_readdir;
+	dir->base_dir.pclosedir = fscache_closedir;
+	dir->pfsentry = list;
+	return (DIR*) dir;
+}
diff --git a/compat/win32/fscache.h b/compat/win32/fscache.h
new file mode 100644
index 00000000000000..ed518b422d705e
--- /dev/null
+++ b/compat/win32/fscache.h
@@ -0,0 +1,10 @@
+#ifndef FSCACHE_H
+#define FSCACHE_H
+
+int fscache_enable(int enable);
+#define enable_fscache(x) fscache_enable(x)
+
+DIR *fscache_opendir(const char *dir);
+int fscache_lstat(const char *file_name, struct stat *buf);
+
+#endif
diff --git a/config.mak.uname b/config.mak.uname
index db076cfbd88e21..937646d8079c38 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -502,7 +502,7 @@ endif
 		compat/win32/path-utils.o \
 		compat/win32/pthread.o compat/win32/syslog.o \
 		compat/win32/trace2_win32_process_info.o \
-		compat/win32/dirent.o
+		compat/win32/dirent.o compat/win32/fscache.o
 	COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DDETECT_MSYS_TTY -DENSURE_MSYSTEM_IS_SET -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
 	BASIC_LDFLAGS = -IGNORE:4217 -IGNORE:4049 -NOLOGO
 	# invalidcontinue.obj allows Git's source code to close the same file
@@ -704,7 +704,7 @@ ifeq ($(uname_S),MINGW)
 		compat/win32/flush.o \
 		compat/win32/path-utils.o \
 		compat/win32/pthread.o compat/win32/syslog.o \
-		compat/win32/dirent.o
+		compat/win32/dirent.o compat/win32/fscache.o
 	BASIC_CFLAGS += -DWIN32
 	EXTLIBS += -lws2_32
 	GITLIBS += git.res
diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index 6e7624467f8c91..9540631852a028 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -308,7 +308,8 @@ if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
 		compat/win32/trace2_win32_process_info.c
 		compat/win32/dirent.c
 		compat/nedmalloc/nedmalloc.c
-		compat/strdup.c)
+		compat/strdup.c
+		compat/win32/fscache.c)
 	set(NO_UNIX_SOCKETS 1)
 
 elseif(CMAKE_SYSTEM_NAME STREQUAL "Linux")
diff --git a/git-compat-util.h b/git-compat-util.h
index c8429efc22c7f1..9b00e08d3e4a8d 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -284,9 +284,11 @@ static inline int is_xplatform_dir_sep(int c)
 /* pull in Windows compatibility stuff */
 #include "compat/win32/path-utils.h"
 #include "compat/mingw.h"
+#include "compat/win32/fscache.h"
 #elif defined(_MSC_VER)
 #include "compat/win32/path-utils.h"
 #include "compat/msvc.h"
+#include "compat/win32/fscache.h"
 #else
 #include <sys/utsname.h>
 #include <sys/wait.h>

From 583d8aa7ee16000006c244d67e70ecce32f4f187 Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Tue, 24 Jan 2017 15:12:13 -0500
Subject: [PATCH 149/259] fscache: add key for GIT_TRACE_FSCACHE

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/win32/fscache.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index 8c7a37c6c0cfce..9f495ac384c925 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -4,11 +4,13 @@
 #include "fscache.h"
 #include "../../dir.h"
 #include "../../abspath.h"
+#include "../../trace.h"
 
 static int initialized;
 static volatile long enabled;
 static struct hashmap map;
 static CRITICAL_SECTION mutex;
+static struct trace_key trace_fscache = TRACE_KEY_INIT(FSCACHE);
 
 /*
  * An entry in the file system cache. Used for both entire directory listings
@@ -207,6 +209,8 @@ static struct fsentry *fsentry_create_list(const struct fsentry *dir)
 	if (h == INVALID_HANDLE_VALUE) {
 		err = GetLastError();
 		errno = (err == ERROR_DIRECTORY) ? ENOTDIR : err_win_to_posix(err);
+		trace_printf_key(&trace_fscache, "fscache: error(%d) '%s'\n",
+						 errno, dir->dirent.d_name);
 		return NULL;
 	}
 
@@ -392,6 +396,7 @@ int fscache_enable(int enable)
 		fscache_clear();
 		LeaveCriticalSection(&mutex);
 	}
+	trace_printf_key(&trace_fscache, "fscache: enable(%d)\n", enable);
 	return result;
 }
 

From 1d30c439a7f1b3b1f9c2046256ac40376a053fa3 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Tue, 24 Jun 2014 13:22:35 +0200
Subject: [PATCH 150/259] fscache: load directories only once

If multiple threads access a directory that is not yet in the cache, the
directory will be loaded by each thread. Only one of the results is added
to the cache, all others are leaked. This wastes performance and memory.

On cache miss, add a future object to the cache to indicate that the
directory is currently being loaded. Subsequent threads register themselves
with the future object and wait. When the first thread has loaded the
directory, it replaces the future object with the result and notifies
waiting threads.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/win32/fscache.c | 65 ++++++++++++++++++++++++++++++++++++------
 1 file changed, 56 insertions(+), 9 deletions(-)

diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index 16e556274614f6..8c7a37c6c0cfce 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -27,6 +27,8 @@ struct fsentry {
 	union {
 		/* Reference count of the directory listing. */
 		volatile long refcnt;
+		/* Handle to wait on the loading thread. */
+		HANDLE hwait;
 		struct {
 			/* More stat members (only used for file entries). */
 			off64_t st_size;
@@ -261,16 +263,43 @@ static inline int fscache_enabled(const char *path)
 	return enabled > 0 && !is_absolute_path(path);
 }
 
+/*
+ * Looks up a cache entry, waits if its being loaded by another thread.
+ * The mutex must be owned by the calling thread.
+ */
+static struct fsentry *fscache_get_wait(struct fsentry *key)
+{
+	struct fsentry *fse = hashmap_get_entry(&map, key, ent, NULL);
+
+	/* return if its a 'real' entry (future entries have refcnt == 0) */
+	if (!fse || fse->list || fse->u.refcnt)
+		return fse;
+
+	/* create an event and link our key to the future entry */
+	key->u.hwait = CreateEvent(NULL, TRUE, FALSE, NULL);
+	key->next = fse->next;
+	fse->next = key;
+
+	/* wait for the loading thread to signal us */
+	LeaveCriticalSection(&mutex);
+	WaitForSingleObject(key->u.hwait, INFINITE);
+	CloseHandle(key->u.hwait);
+	EnterCriticalSection(&mutex);
+
+	/* repeat cache lookup */
+	return hashmap_get_entry(&map, key, ent, NULL);
+}
+
 /*
  * Looks up or creates a cache entry for the specified key.
  */
 static struct fsentry *fscache_get(struct fsentry *key)
 {
-	struct fsentry *fse;
+	struct fsentry *fse, *future, *waiter;
 
 	EnterCriticalSection(&mutex);
 	/* check if entry is in cache */
-	fse = hashmap_get_entry(&map, key, ent, NULL);
+	fse = fscache_get_wait(key);
 	if (fse) {
 		fsentry_addref(fse);
 		LeaveCriticalSection(&mutex);
@@ -278,7 +307,7 @@ static struct fsentry *fscache_get(struct fsentry *key)
 	}
 	/* if looking for a file, check if directory listing is in cache */
 	if (!fse && key->list) {
-		fse = hashmap_get_entry(&map, key->list, ent, NULL);
+		fse = fscache_get_wait(key->list);
 		if (fse) {
 			LeaveCriticalSection(&mutex);
 			/* dir entry without file entry -> file doesn't exist */
@@ -287,16 +316,34 @@ static struct fsentry *fscache_get(struct fsentry *key)
 		}
 	}
 
+	/* add future entry to indicate that we're loading it */
+	future = key->list ? key->list : key;
+	future->next = NULL;
+	future->u.refcnt = 0;
+	hashmap_add(&map, &future->ent);
+
 	/* create the directory listing (outside mutex!) */
 	LeaveCriticalSection(&mutex);
-	fse = fsentry_create_list(key->list ? key->list : key);
-	if (!fse)
+	fse = fsentry_create_list(future);
+	EnterCriticalSection(&mutex);
+
+	/* remove future entry and signal waiting threads */
+	hashmap_remove(&map, &future->ent, NULL);
+	waiter = future->next;
+	while (waiter) {
+		HANDLE h = waiter->u.hwait;
+		waiter = waiter->next;
+		SetEvent(h);
+	}
+
+	/* leave on error (errno set by fsentry_create_list) */
+	if (!fse) {
+		LeaveCriticalSection(&mutex);
 		return NULL;
+	}
 
-	EnterCriticalSection(&mutex);
-	/* add directory listing if it hasn't been added by some other thread */
-	if (!hashmap_get_entry(&map, key, ent, NULL))
-		fscache_add(fse);
+	/* add directory listing to the cache */
+	fscache_add(fse);
 
 	/* lookup file entry if requested (fse already points to directory) */
 	if (key->list)

From 851b171444b73dc8c22460745bb39f399d2e60ca Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Wed, 1 Nov 2017 15:05:44 -0400
Subject: [PATCH 151/259] dir.c: make add_excludes aware of fscache during
 status

Teach read_directory_recursive() and add_excludes() to
be aware of optional fscache and avoid trying to open()
and fstat() non-existant ".gitignore" files in every
directory in the worktree.

The current code in add_excludes() calls open() and then
fstat() for a ".gitignore" file in each directory present
in the worktree.  Change that when fscache is enabled to
call lstat() first and if present, call open().

This seems backwards because both lstat needs to do more
work than fstat.  But when fscache is enabled, fscache will
already know if the .gitignore file exists and can completely
avoid the IO calls.  This works because of the lstat diversion
to mingw_lstat when fscache is enabled.

This reduced status times on a 350K file enlistment of the
Windows repo on a NVMe SSD by 0.25 seconds.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 compat/win32/fscache.c |  5 +++++
 compat/win32/fscache.h |  3 +++
 dir.c                  | 33 ++++++++++++++++++++++++---------
 git-compat-util.h      |  4 ++++
 4 files changed, 36 insertions(+), 9 deletions(-)

diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index a79096839e5c31..e22660237b955f 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -12,6 +12,11 @@ static struct hashmap map;
 static CRITICAL_SECTION mutex;
 static struct trace_key trace_fscache = TRACE_KEY_INIT(FSCACHE);
 
+int fscache_is_enabled(void)
+{
+	return enabled;
+}
+
 /*
  * An entry in the file system cache. Used for both entire directory listings
  * and file entries.
diff --git a/compat/win32/fscache.h b/compat/win32/fscache.h
index ed518b422d705e..9a21fd5709c5bc 100644
--- a/compat/win32/fscache.h
+++ b/compat/win32/fscache.h
@@ -4,6 +4,9 @@
 int fscache_enable(int enable);
 #define enable_fscache(x) fscache_enable(x)
 
+int fscache_is_enabled(void);
+#define is_fscache_enabled() (fscache_is_enabled())
+
 DIR *fscache_opendir(const char *dir);
 int fscache_lstat(const char *file_name, struct stat *buf);
 
diff --git a/dir.c b/dir.c
index 5a23376bdaec3a..7e8a0dff88965d 100644
--- a/dir.c
+++ b/dir.c
@@ -1113,16 +1113,31 @@ static int add_patterns(const char *fname, const char *base, int baselen,
 	size_t size = 0;
 	char *buf;
 
-	if (flags & PATTERN_NOFOLLOW)
-		fd = open_nofollow(fname, O_RDONLY);
-	else
-		fd = open(fname, O_RDONLY);
-
-	if (fd < 0 || fstat(fd, &st) < 0) {
-		if (fd < 0)
-			warn_on_fopen_errors(fname);
+	if (is_fscache_enabled()) {
+		if (lstat(fname, &st) < 0) {
+			fd = -1;
+		} else {
+			fd = open(fname, O_RDONLY);
+			if (fd < 0)
+				warn_on_fopen_errors(fname);
+		}
+	} else {
+		if (flags & PATTERN_NOFOLLOW)
+			fd = open_nofollow(fname, O_RDONLY);
 		else
-			close(fd);
+			fd = open(fname, O_RDONLY);
+
+		if (fd < 0 || fstat(fd, &st) < 0) {
+			if (fd < 0)
+				warn_on_fopen_errors(fname);
+			else {
+				close(fd);
+				fd = -1;
+			}
+		}
+	}
+
+	if (fd < 0) {
 		if (!istate)
 			return -1;
 		r = read_skip_worktree_file_from_index(istate, fname,
diff --git a/git-compat-util.h b/git-compat-util.h
index 9b00e08d3e4a8d..79d9bba2c2f692 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1537,6 +1537,10 @@ static inline int is_missing_file_error(int errno_)
 #define enable_fscache(x) /* noop */
 #endif
 
+#ifndef is_fscache_enabled
+#define is_fscache_enabled() (0)
+#endif
+
 int cmd_main(int, const char **);
 
 /*

From 61d45de42bb8333834decdd83f9177de1d836ba8 Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Tue, 13 Dec 2016 14:05:32 -0500
Subject: [PATCH 152/259] fscache: remember not-found directories

Teach FSCACHE to remember "not found" directories.

This is a performance optimization.

FSCACHE is a performance optimization available for Windows.  It
intercepts Posix-style lstat() calls into an in-memory directory
using FindFirst/FindNext.  It improves performance on Windows by
catching the first lstat() call in a directory, using FindFirst/
FindNext to read the list of files (and attribute data) for the
entire directory into the cache, and short-cut subsequent lstat()
calls in the same directory.  This gives a major performance
boost on Windows.

However, it does not remember "not found" directories.  When STATUS
runs and there are missing directories, the lstat() interception
fails to find the parent directory and simply return ENOENT for the
file -- it does not remember that the FindFirst on the directory
failed. Thus subsequent lstat() calls in the same directory, each
re-attempt the FindFirst.  This completely defeats any performance
gains.

This can be seen by doing a sparse-checkout on a large repo and
then doing a read-tree to reset the skip-worktree bits and then
running status.

This change reduced status times for my very large repo by 60%.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/win32/fscache.c | 36 ++++++++++++++++++++++++++++++++----
 1 file changed, 32 insertions(+), 4 deletions(-)

diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index 9f495ac384c925..a79096839e5c31 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -181,7 +181,8 @@ static struct fsentry *fseentry_create_entry(struct fsentry *list,
  * Dir should not contain trailing '/'. Use an empty string for the current
  * directory (not "."!).
  */
-static struct fsentry *fsentry_create_list(const struct fsentry *dir)
+static struct fsentry *fsentry_create_list(const struct fsentry *dir,
+					   int *dir_not_found)
 {
 	wchar_t pattern[MAX_PATH + 2]; /* + 2 for '/' '*' */
 	WIN32_FIND_DATAW fdata;
@@ -190,6 +191,8 @@ static struct fsentry *fsentry_create_list(const struct fsentry *dir)
 	struct fsentry *list, **phead;
 	DWORD err;
 
+	*dir_not_found = 0;
+
 	/* convert name to UTF-16 and check length < MAX_PATH */
 	if ((wlen = xutftowcsn(pattern, dir->dirent.d_name, MAX_PATH,
 			       dir->len)) < 0) {
@@ -208,6 +211,7 @@ static struct fsentry *fsentry_create_list(const struct fsentry *dir)
 	h = FindFirstFileW(pattern, &fdata);
 	if (h == INVALID_HANDLE_VALUE) {
 		err = GetLastError();
+		*dir_not_found = 1; /* or empty directory */
 		errno = (err == ERROR_DIRECTORY) ? ENOTDIR : err_win_to_posix(err);
 		trace_printf_key(&trace_fscache, "fscache: error(%d) '%s'\n",
 						 errno, dir->dirent.d_name);
@@ -216,6 +220,8 @@ static struct fsentry *fsentry_create_list(const struct fsentry *dir)
 
 	/* allocate object to hold directory listing */
 	list = fsentry_alloc(NULL, dir->dirent.d_name, dir->len);
+	list->st_mode = S_IFDIR;
+	list->dirent.d_type = DT_DIR;
 
 	/* walk directory and build linked list of fsentry structures */
 	phead = &list->next;
@@ -300,12 +306,16 @@ static struct fsentry *fscache_get_wait(struct fsentry *key)
 static struct fsentry *fscache_get(struct fsentry *key)
 {
 	struct fsentry *fse, *future, *waiter;
+	int dir_not_found;
 
 	EnterCriticalSection(&mutex);
 	/* check if entry is in cache */
 	fse = fscache_get_wait(key);
 	if (fse) {
-		fsentry_addref(fse);
+		if (fse->st_mode)
+			fsentry_addref(fse);
+		else
+			fse = NULL; /* non-existing directory */
 		LeaveCriticalSection(&mutex);
 		return fse;
 	}
@@ -314,7 +324,10 @@ static struct fsentry *fscache_get(struct fsentry *key)
 		fse = fscache_get_wait(key->list);
 		if (fse) {
 			LeaveCriticalSection(&mutex);
-			/* dir entry without file entry -> file doesn't exist */
+			/*
+			 * dir entry without file entry, or dir does not
+			 * exist -> file doesn't exist
+			 */
 			errno = ENOENT;
 			return NULL;
 		}
@@ -328,7 +341,7 @@ static struct fsentry *fscache_get(struct fsentry *key)
 
 	/* create the directory listing (outside mutex!) */
 	LeaveCriticalSection(&mutex);
-	fse = fsentry_create_list(future);
+	fse = fsentry_create_list(future, &dir_not_found);
 	EnterCriticalSection(&mutex);
 
 	/* remove future entry and signal waiting threads */
@@ -342,6 +355,18 @@ static struct fsentry *fscache_get(struct fsentry *key)
 
 	/* leave on error (errno set by fsentry_create_list) */
 	if (!fse) {
+		if (dir_not_found && key->list) {
+			/*
+			 * Record that the directory does not exist (or is
+			 * empty, which for all practical matters is the same
+			 * thing as far as fscache is concerned).
+			 */
+			fse = fsentry_alloc(key->list->list,
+					    key->list->dirent.d_name,
+					    key->list->len);
+			fse->st_mode = 0;
+			hashmap_add(&map, &fse->ent);
+		}
 		LeaveCriticalSection(&mutex);
 		return NULL;
 	}
@@ -353,6 +378,9 @@ static struct fsentry *fscache_get(struct fsentry *key)
 	if (key->list)
 		fse = hashmap_get_entry(&map, key, ent, NULL);
 
+	if (fse && !fse->st_mode)
+		fse = NULL; /* non-existing directory */
+
 	/* return entry or ENOENT */
 	if (fse)
 		fsentry_addref(fse);

From 0a4e8f81d8a41681d861cb178727c0dbb6827a7f Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Wed, 20 Dec 2017 10:43:41 -0500
Subject: [PATCH 153/259] fscache: make fscache_enabled() public

Make fscache_enabled() function public rather than static.
Remove unneeded fscache_is_enabled() function.
Change is_fscache_enabled() macro to call fscache_enabled().

is_fscache_enabled() now takes a pathname so that the answer
is more precise and mean "is fscache enabled for this pathname",
since fscache only stores repo-relative paths and not absolute
paths, we can avoid attempting lookups for absolute paths.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 compat/win32/fscache.c | 7 +------
 compat/win32/fscache.h | 4 ++--
 dir.c                  | 2 +-
 git-compat-util.h      | 2 +-
 4 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index e22660237b955f..88907836890af1 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -12,11 +12,6 @@ static struct hashmap map;
 static CRITICAL_SECTION mutex;
 static struct trace_key trace_fscache = TRACE_KEY_INIT(FSCACHE);
 
-int fscache_is_enabled(void)
-{
-	return enabled;
-}
-
 /*
  * An entry in the file system cache. Used for both entire directory listings
  * and file entries.
@@ -273,7 +268,7 @@ static void fscache_clear(void)
 /*
  * Checks if the cache is enabled for the given path.
  */
-static inline int fscache_enabled(const char *path)
+int fscache_enabled(const char *path)
 {
 	return enabled > 0 && !is_absolute_path(path);
 }
diff --git a/compat/win32/fscache.h b/compat/win32/fscache.h
index 9a21fd5709c5bc..660ada053b4309 100644
--- a/compat/win32/fscache.h
+++ b/compat/win32/fscache.h
@@ -4,8 +4,8 @@
 int fscache_enable(int enable);
 #define enable_fscache(x) fscache_enable(x)
 
-int fscache_is_enabled(void);
-#define is_fscache_enabled() (fscache_is_enabled())
+int fscache_enabled(const char *path);
+#define is_fscache_enabled(path) fscache_enabled(path)
 
 DIR *fscache_opendir(const char *dir);
 int fscache_lstat(const char *file_name, struct stat *buf);
diff --git a/dir.c b/dir.c
index 7e8a0dff88965d..40d4186de467fc 100644
--- a/dir.c
+++ b/dir.c
@@ -1113,7 +1113,7 @@ static int add_patterns(const char *fname, const char *base, int baselen,
 	size_t size = 0;
 	char *buf;
 
-	if (is_fscache_enabled()) {
+	if (is_fscache_enabled(fname)) {
 		if (lstat(fname, &st) < 0) {
 			fd = -1;
 		} else {
diff --git a/git-compat-util.h b/git-compat-util.h
index 79d9bba2c2f692..3bd5804b26930a 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1538,7 +1538,7 @@ static inline int is_missing_file_error(int errno_)
 #endif
 
 #ifndef is_fscache_enabled
-#define is_fscache_enabled() (0)
+#define is_fscache_enabled(path) (0)
 #endif
 
 int cmd_main(int, const char **);

From 664e8ac58949f2eac0551760d072fe910d0b5a14 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 25 Jan 2017 18:39:16 +0100
Subject: [PATCH 154/259] fscache: add a test for the dir-not-found
 optimization

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t1090-sparse-checkout-scope.sh | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/t/t1090-sparse-checkout-scope.sh b/t/t1090-sparse-checkout-scope.sh
index da0e7714d5ac5c..b6298e7e7d8ab1 100755
--- a/t/t1090-sparse-checkout-scope.sh
+++ b/t/t1090-sparse-checkout-scope.sh
@@ -107,4 +107,24 @@ test_expect_success 'in partial clone, sparse checkout only fetches needed blobs
 	test_cmp expect actual
 '
 
+test_expect_success MINGW 'no unnecessary opendir() with fscache' '
+	git clone . fscache-test &&
+	(
+		cd fscache-test &&
+		git config core.fscache 1 &&
+		echo "/excluded/*" >.git/info/sparse-checkout &&
+		for f in $(test_seq 10)
+		do
+			sha1=$(echo $f | git hash-object -w --stdin) &&
+			git update-index --add \
+				--cacheinfo 100644,$sha1,excluded/$f || exit 1
+		done &&
+		test_tick &&
+		git commit -m excluded &&
+		GIT_TRACE_FSCACHE=1 git status >out 2>err &&
+		grep excluded err >grep.out &&
+		test_line_count = 1 grep.out
+	)
+'
+
 test_done

From 0ae9145721cdd3ff5b52bc3b82e9391a7d817350 Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Tue, 22 Nov 2016 11:26:38 -0500
Subject: [PATCH 155/259] add: use preload-index and fscache for performance

Teach "add" to use preload-index and fscache features
to improve performance on very large repositories.

During an "add", a call is made to run_diff_files()
which calls check_remove() for each index-entry.  This
calls lstat().  On Windows, the fscache code intercepts
the lstat() calls and builds a private cache using the
FindFirst/FindNext routines, which are much faster.

Somewhat independent of this, is the preload-index code
which distributes some of the start-up costs across
multiple threads.

We need to keep the call to read_cache() before parsing the
pathspecs (and hence cannot use the pathspecs to limit any preload)
because parse_pathspec() is using the index to determine whether a
pathspec is, in fact, in a submodule. If we would not read the index
first, parse_pathspec() would not error out on a path that is inside
a submodule, and t7400-submodule-basic.sh would fail with

	not ok 47 - do not add files from a submodule

We still want the nice preload performance boost, though, so we simply
call read_cache_preload(&pathspecs) after parsing the pathspecs.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 builtin/add.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/builtin/add.c b/builtin/add.c
index 40b61ef90d98ca..a17484ba4980aa 100644
--- a/builtin/add.c
+++ b/builtin/add.c
@@ -460,6 +460,10 @@ int cmd_add(int argc, const char **argv, const char *prefix)
 	die_in_unpopulated_submodule(the_repository->index, prefix);
 	die_path_inside_submodule(the_repository->index, &pathspec);
 
+	enable_fscache(1);
+	/* We do not really re-read the index but update the up-to-date flags */
+	preload_index(the_repository->index, &pathspec, 0);
+
 	if (add_new_files) {
 		int baselen;
 
@@ -572,5 +576,6 @@ int cmd_add(int argc, const char **argv, const char *prefix)
 	free(ps_matched);
 	dir_clear(&dir);
 	clear_pathspec(&pathspec);
+	enable_fscache(0);
 	return exit_status;
 }

From 5ea907f0e0083ca5a6afa57f4a8100d4b37e03e6 Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Wed, 20 Dec 2017 11:19:27 -0500
Subject: [PATCH 156/259] dir.c: regression fix for add_excludes with fscache

Fix regression described in:
https://github.com/git-for-windows/git/issues/1392

which was introduced in:
https://github.com/git-for-windows/git/commit/b2353379bba414e6c00dde913497cc9c827366f2

Problem Symptoms
================
When the user has a .gitignore file that is a symlink, the fscache
optimization introduced above caused the stat-data from the symlink,
rather that of the target file, to be returned.  Later when the ignore
file was read, the buffer length did not match the stat.st_size field
and we called die("cannot use <path> as an exclude file")

Optimization Rationale
======================
The above optimization calls lstat() before open() primarily to ask
fscache if the file exists.  It gets the current stat-data as a side
effect essentially for free (since we already have it in memory).
If the file does not exist, it does not need to call open().  And
since very few directories have .gitignore files, we can greatly
reduce time spent in the filesystem.

Discussion of Fix
=================
The above optimization calls lstat() rather than stat() because the
fscache only intercepts lstat() calls.  Calls to stat() stay directed
to the mingw_stat() completly bypassing fscache.  Furthermore, calls
to mingw_stat() always call {open, fstat, close} so that symlinks are
properly dereferenced, which adds *additional* open/close calls on top
of what the original code in dir.c is doing.

Since the problem only manifests for symlinks, we add code to overwrite
the stat-data when the path is a symlink.  This preserves the effect of
the performance gains provided by the fscache in the normal case.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 dir.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/dir.c b/dir.c
index 40d4186de467fc..837c812a149e08 100644
--- a/dir.c
+++ b/dir.c
@@ -1113,6 +1113,29 @@ static int add_patterns(const char *fname, const char *base, int baselen,
 	size_t size = 0;
 	char *buf;
 
+	/*
+	 * A performance optimization for status.
+	 *
+	 * During a status scan, git looks in each directory for a .gitignore
+	 * file before scanning the directory.  Since .gitignore files are not
+	 * that common, we can waste a lot of time looking for files that are
+	 * not there.  Fortunately, the fscache already knows if the directory
+	 * contains a .gitignore file, since it has already read the directory
+	 * and it already has the stat-data.
+	 *
+	 * If the fscache is enabled, use the fscache-lstat() interlude to see
+	 * if the file exists (in the fscache hash maps) before trying to open()
+	 * it.
+	 *
+	 * This causes problem when the .gitignore file is a symlink, because
+	 * we call lstat() rather than stat() on the symlnk and the resulting
+	 * stat-data is for the symlink itself rather than the target file.
+	 * We CANNOT use stat() here because the fscache DOES NOT install an
+	 * interlude for stat() and mingw_stat() always calls "open-fstat-close"
+	 * on the file and defeats the purpose of the optimization here.  Since
+	 * symlinks are even more rare than .gitignore files, we force a fstat()
+	 * after our open() to get stat-data for the target file.
+	 */
 	if (is_fscache_enabled(fname)) {
 		if (lstat(fname, &st) < 0) {
 			fd = -1;
@@ -1120,6 +1143,11 @@ static int add_patterns(const char *fname, const char *base, int baselen,
 			fd = open(fname, O_RDONLY);
 			if (fd < 0)
 				warn_on_fopen_errors(fname);
+			else if (S_ISLNK(st.st_mode) && fstat(fd, &st) < 0) {
+				warn_on_fopen_errors(fname);
+				close(fd);
+				fd = -1;
+			}
 		}
 	} else {
 		if (flags & PATTERN_NOFOLLOW)

From 4579d695ace2c2f6f744ced09fb93d8db4ed9c88 Mon Sep 17 00:00:00 2001
From: Takuto Ikuta <tikuta@chromium.org>
Date: Wed, 22 Nov 2017 20:39:38 +0900
Subject: [PATCH 157/259] fetch-pack.c: enable fscache for stats under
 .git/objects

When I do git fetch, git call file stats under .git/objects for each
refs. This takes time when there are many refs.

By enabling fscache, git takes file stats by directory traversing and that
improved the speed of fetch-pack for repository having large number of
refs.

In my windows workstation, this improves the time of `git fetch` for
chromium repository like below. I took stats 3 times.

* With this patch
TotalSeconds: 9.9825165
TotalSeconds: 9.1862075
TotalSeconds: 10.1956256
Avg: 9.78811653333333

* Without this patch
TotalSeconds: 15.8406702
TotalSeconds: 15.6248053
TotalSeconds: 15.2085938
Avg: 15.5580231

Signed-off-by: Takuto Ikuta <tikuta@chromium.org>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 fetch-pack.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fetch-pack.c b/fetch-pack.c
index 732511604b1a6c..89279c73d6b05b 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -757,6 +757,7 @@ static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 	save_commit_buffer = 0;
 
 	trace2_region_enter("fetch-pack", "parse_remote_refs_and_find_cutoff", NULL);
+	enable_fscache(1);
 	for (ref = *refs; ref; ref = ref->next) {
 		struct commit *commit;
 
@@ -783,6 +784,7 @@ static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 		if (!cutoff || cutoff < commit->date)
 			cutoff = commit->date;
 	}
+	enable_fscache(0);
 	trace2_region_leave("fetch-pack", "parse_remote_refs_and_find_cutoff", NULL);
 
 	/*

From af3cee0c140583c7100673a62e4d08b9adac2fc5 Mon Sep 17 00:00:00 2001
From: Takuto Ikuta <tikuta@chromium.org>
Date: Tue, 30 Jan 2018 22:42:58 +0900
Subject: [PATCH 158/259] checkout.c: enable fscache for checkout again

This is retry of #1419.

I added flush_fscache macro to flush cached stats after disk writing
with tests for regression reported in #1438 and #1442.

git checkout checks each file path in sorted order, so cache flushing does not
make performance worse unless we have large number of modified files in
a directory containing many files.

Using chromium repository, I tested `git checkout .` performance when I
delete 10 files in different directories.
With this patch:
TotalSeconds: 4.307272
TotalSeconds: 4.4863595
TotalSeconds: 4.2975562
Avg: 4.36372923333333

Without this patch:
TotalSeconds: 20.9705431
TotalSeconds: 22.4867685
TotalSeconds: 18.8968292
Avg: 20.7847136

I confirmed this patch passed all tests in t/ with core_fscache=1.

Signed-off-by: Takuto Ikuta <tikuta@chromium.org>
---
 builtin/checkout.c     |  2 ++
 compat/win32/fscache.c | 12 ++++++++++++
 compat/win32/fscache.h |  3 +++
 entry.c                |  3 +++
 git-compat-util.h      |  4 ++++
 parallel-checkout.c    |  1 +
 t/t7201-co.sh          | 36 ++++++++++++++++++++++++++++++++++++
 7 files changed, 61 insertions(+)

diff --git a/builtin/checkout.c b/builtin/checkout.c
index 1748d68c961f6b..e19edfc0507f2f 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -403,6 +403,7 @@ static int checkout_worktree(const struct checkout_opts *opts,
 	if (pc_workers > 1)
 		init_parallel_checkout();
 
+	enable_fscache(1);
 	for (pos = 0; pos < the_repository->index->cache_nr; pos++) {
 		struct cache_entry *ce = the_repository->index->cache[pos];
 		if (ce->ce_flags & CE_MATCHED) {
@@ -428,6 +429,7 @@ static int checkout_worktree(const struct checkout_opts *opts,
 		errs |= run_parallel_checkout(&state, pc_workers, pc_threshold,
 					      NULL, NULL);
 	mem_pool_discard(&ce_mem_pool, should_validate_cache_entries());
+	enable_fscache(0);
 	remove_marked_cache_entries(the_repository->index, 1);
 	remove_scheduled_dirs();
 	errs |= finish_delayed_checkout(&state, opts->show_progress);
diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index 88907836890af1..932e90ad4da4f7 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -428,6 +428,18 @@ int fscache_enable(int enable)
 	return result;
 }
 
+/*
+ * Flush cached stats result when fscache is enabled.
+ */
+void fscache_flush(void)
+{
+	if (enabled) {
+		EnterCriticalSection(&mutex);
+		fscache_clear();
+		LeaveCriticalSection(&mutex);
+	}
+}
+
 /*
  * Lstat replacement, uses the cache if enabled, otherwise redirects to
  * mingw_lstat.
diff --git a/compat/win32/fscache.h b/compat/win32/fscache.h
index 660ada053b4309..2f06f8df97dcd0 100644
--- a/compat/win32/fscache.h
+++ b/compat/win32/fscache.h
@@ -7,6 +7,9 @@ int fscache_enable(int enable);
 int fscache_enabled(const char *path);
 #define is_fscache_enabled(path) fscache_enabled(path)
 
+void fscache_flush(void);
+#define flush_fscache() fscache_flush()
+
 DIR *fscache_opendir(const char *dir);
 int fscache_lstat(const char *file_name, struct stat *buf);
 
diff --git a/entry.c b/entry.c
index e7ed440ce2277e..75fdd39ff7db40 100644
--- a/entry.c
+++ b/entry.c
@@ -407,6 +407,9 @@ static int write_entry(struct cache_entry *ce, char *path, struct conv_attrs *ca
 	}
 
 finish:
+	/* Flush cached lstat in fscache after writing to disk. */
+	flush_fscache();
+
 	if (state->refresh_cache) {
 		if (!fstat_done && lstat(ce->name, &st) < 0)
 			return error_errno("unable to stat just-written file %s",
diff --git a/git-compat-util.h b/git-compat-util.h
index 3bd5804b26930a..529ab6a9834f7f 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1541,6 +1541,10 @@ static inline int is_missing_file_error(int errno_)
 #define is_fscache_enabled(path) (0)
 #endif
 
+#ifndef flush_fscache
+#define flush_fscache() /* noop */
+#endif
+
 int cmd_main(int, const char **);
 
 /*
diff --git a/parallel-checkout.c b/parallel-checkout.c
index 08b960aac84b0d..1b5f904f7b7d9f 100644
--- a/parallel-checkout.c
+++ b/parallel-checkout.c
@@ -636,6 +636,7 @@ static void write_items_sequentially(struct checkout *state)
 {
 	size_t i;
 
+	flush_fscache();
 	for (i = 0; i < parallel_checkout.nr; i++) {
 		struct parallel_checkout_item *pc_item = &parallel_checkout.items[i];
 		write_pc_item(pc_item, state);
diff --git a/t/t7201-co.sh b/t/t7201-co.sh
index 2d984eb4c6a167..3bbc195c2a3169 100755
--- a/t/t7201-co.sh
+++ b/t/t7201-co.sh
@@ -36,6 +36,42 @@ fill () {
 }
 
 
+test_expect_success MINGW 'fscache flush cache' '
+
+	git init fscache-test &&
+	cd fscache-test &&
+	git config core.fscache 1 &&
+	echo A > test.txt &&
+	git add test.txt &&
+	git commit -m A &&
+	echo B >> test.txt &&
+	git checkout . &&
+	test -z "$(git status -s)" &&
+	echo A > expect.txt &&
+	test_cmp expect.txt test.txt &&
+	cd .. &&
+	rm -rf fscache-test
+'
+
+test_expect_success MINGW 'fscache flush cache dir' '
+
+	git init fscache-test &&
+	cd fscache-test &&
+	git config core.fscache 1 &&
+	echo A > test.txt &&
+	git add test.txt &&
+	git commit -m A &&
+	rm test.txt &&
+	mkdir test.txt &&
+	touch test.txt/test.txt &&
+	git checkout . &&
+	test -z "$(git status -s)" &&
+	echo A > expect.txt &&
+	test_cmp expect.txt test.txt &&
+	cd .. &&
+	rm -rf fscache-test
+'
+
 test_expect_success setup '
 	fill x y z >same &&
 	fill 1 2 3 4 5 6 7 8 >one &&

From 532b6f5b8177cf8fc025a33a74d457879d3e6264 Mon Sep 17 00:00:00 2001
From: Ben Peart <benpeart@microsoft.com>
Date: Fri, 7 Sep 2018 11:39:57 -0400
Subject: [PATCH 159/259] Enable the filesystem cache (fscache) in
 refresh_index().

On file systems that support it, this can dramatically speed up operations
like add, commit, describe, rebase, reset, rm that would otherwise have to
lstat() every file to "re-match" the stat information in the index to that
of the file system.

On a synthetic repo with 1M files, "git reset" dropped from 52.02 seconds to
14.42 seconds for a savings of 72%.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
---
 read-cache.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/read-cache.c b/read-cache.c
index 1f67bb755b1cd1..009343eda25273 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -1530,6 +1530,7 @@ int refresh_index(struct index_state *istate, unsigned int flags,
 	typechange_fmt = in_porcelain ? "T\t%s\n" : "%s: needs update\n";
 	added_fmt      = in_porcelain ? "A\t%s\n" : "%s: needs update\n";
 	unmerged_fmt   = in_porcelain ? "U\t%s\n" : "%s: needs merge\n";
+	enable_fscache(1);
 	/*
 	 * Use the multi-threaded preload_index() to refresh most of the
 	 * cache entries quickly then in the single threaded loop below,
@@ -1624,6 +1625,7 @@ int refresh_index(struct index_state *istate, unsigned int flags,
 	display_progress(progress, istate->cache_nr);
 	stop_progress(&progress);
 	trace_performance_leave("refresh index");
+	enable_fscache(0);
 	return has_errors;
 }
 

From baf01369f4feb2849693258cf626417d9a4ec67b Mon Sep 17 00:00:00 2001
From: Ben Peart <benpeart@microsoft.com>
Date: Tue, 23 Oct 2018 11:42:06 -0400
Subject: [PATCH 160/259] fscache: use FindFirstFileExW to avoid retrieving the
 short name

Use FindFirstFileExW with FindExInfoBasic to avoid forcing NTFS to look up
the short name.  Also switch to a larger (64K vs 4K) buffer using
FIND_FIRST_EX_LARGE_FETCH to minimize round trips to the kernel.

In a repo with ~200K files, this drops warm cache status times from 3.19
seconds to 2.67 seconds for a 16% savings.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
---
 compat/win32/fscache.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index 932e90ad4da4f7..7bf44e0f3a76d2 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -208,7 +208,8 @@ static struct fsentry *fsentry_create_list(const struct fsentry *dir,
 	pattern[wlen] = 0;
 
 	/* open find handle */
-	h = FindFirstFileW(pattern, &fdata);
+	h = FindFirstFileExW(pattern, FindExInfoBasic, &fdata, FindExSearchNameMatch,
+		NULL, FIND_FIRST_EX_LARGE_FETCH);
 	if (h == INVALID_HANDLE_VALUE) {
 		err = GetLastError();
 		*dir_not_found = 1; /* or empty directory */

From 174e972670dd32cbbd720cff657af4ce52f2f374 Mon Sep 17 00:00:00 2001
From: Ben Peart <benpeart@microsoft.com>
Date: Thu, 1 Nov 2018 11:40:51 -0400
Subject: [PATCH 161/259] status: disable and free fscache at the end of the
 status command

At the end of the status command, disable and free the fscache so that we
don't leak the memory and so that we can dump the fscache statistics.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
---
 builtin/commit.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/builtin/commit.c b/builtin/commit.c
index 794ea24d9ab9a0..1f61c538faf84e 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -1609,6 +1609,7 @@ int cmd_status(int argc, const char **argv, const char *prefix)
 	wt_status_print(&s);
 	wt_status_collect_free_buffers(&s);
 
+	enable_fscache(0);
 	return 0;
 }
 

From 26798fc386f46605b616af683f8e95d6495ab121 Mon Sep 17 00:00:00 2001
From: Ben Peart <benpeart@microsoft.com>
Date: Thu, 4 Oct 2018 18:10:21 -0400
Subject: [PATCH 162/259] fscache: add GIT_TEST_FSCACHE support

Add support to fscache to enable running the entire test suite with the
fscache enabled.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
---
 compat/win32/fscache.c | 5 +++++
 t/README               | 3 +++
 2 files changed, 8 insertions(+)

diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index 7bf44e0f3a76d2..029c1fb1693911 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -5,6 +5,7 @@
 #include "../../dir.h"
 #include "../../abspath.h"
 #include "../../trace.h"
+#include "config.h"
 
 static int initialized;
 static volatile long enabled;
@@ -401,7 +402,11 @@ int fscache_enable(int enable)
 	int result;
 
 	if (!initialized) {
+		int fscache = git_env_bool("GIT_TEST_FSCACHE", -1);
+
 		/* allow the cache to be disabled entirely */
+		if (fscache != -1)
+			core_fscache = fscache;
 		if (!core_fscache)
 			return 0;
 
diff --git a/t/README b/t/README
index c0a0d7ed65e5d2..87285a29151cc1 100644
--- a/t/README
+++ b/t/README
@@ -492,6 +492,9 @@ GIT_TEST_FULL_NAME_HASH=<boolean>, when true, sets the default name-hash
 function in 'git pack-objects' to be the one used by the --full-name-hash
 option.
 
+GIT_TEST_FSCACHE=<boolean> exercises the uncommon fscache code path
+which adds a cache below mingw's lstat and dirent implementations.
+
 Naming Tests
 ------------
 

From 203101dc55f0731714e7fd81a3abfba5b502b172 Mon Sep 17 00:00:00 2001
From: Ben Peart <benpeart@microsoft.com>
Date: Thu, 4 Oct 2018 18:10:21 -0400
Subject: [PATCH 163/259] mem_pool: add GIT_TRACE_MEMPOOL support

Add tracing around initializing and discarding mempools. In discard report
on the amount of memory unused in the current block to help tune setting
the initial_size.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
---
 mem-pool.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/mem-pool.c b/mem-pool.c
index a3ba38831d94d6..f1264bcf9ddfa1 100644
--- a/mem-pool.c
+++ b/mem-pool.c
@@ -5,7 +5,9 @@
 #include "git-compat-util.h"
 #include "mem-pool.h"
 #include "gettext.h"
+#include "trace.h"
 
+static struct trace_key trace_mem_pool = TRACE_KEY_INIT(MEMPOOL);
 #define BLOCK_GROWTH_SIZE (1024 * 1024 - sizeof(struct mp_block))
 
 /*
@@ -63,12 +65,20 @@ void mem_pool_init(struct mem_pool *pool, size_t initial_size)
 
 	if (initial_size > 0)
 		mem_pool_alloc_block(pool, initial_size, NULL);
+
+	trace_printf_key(&trace_mem_pool,
+		"mem_pool (%p): init (%"PRIuMAX") initial size\n",
+		(void *)pool, (uintmax_t)initial_size);
 }
 
 void mem_pool_discard(struct mem_pool *pool, int invalidate_memory)
 {
 	struct mp_block *block, *block_to_free;
 
+	trace_printf_key(&trace_mem_pool,
+		"mem_pool (%p): discard (%"PRIuMAX") unused\n",
+		(void *)pool,
+		(uintmax_t)(pool->mp_block->end - pool->mp_block->next_free));
 	block = pool->mp_block;
 	while (block)
 	{

From 1746116df1535549853c0aa7a546d88b5cfa0543 Mon Sep 17 00:00:00 2001
From: Ben Peart <benpeart@microsoft.com>
Date: Fri, 2 Nov 2018 11:19:10 -0400
Subject: [PATCH 164/259] fscache: fscache takes an initial size

Update enable_fscache() to take an optional initial size parameter which is
used to initialize the hashmap so that it can avoid having to rehash as
additional entries are added.

Add a separate disable_fscache() macro to make the code clearer and easier
to read.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 builtin/add.c          | 2 +-
 builtin/checkout.c     | 4 ++--
 builtin/commit.c       | 4 ++--
 compat/win32/fscache.c | 8 ++++++--
 compat/win32/fscache.h | 5 +++--
 fetch-pack.c           | 4 ++--
 git-compat-util.h      | 4 ++++
 preload-index.c        | 4 ++--
 read-cache.c           | 4 ++--
 9 files changed, 24 insertions(+), 15 deletions(-)

diff --git a/builtin/add.c b/builtin/add.c
index a17484ba4980aa..077f5c171a90b5 100644
--- a/builtin/add.c
+++ b/builtin/add.c
@@ -460,7 +460,7 @@ int cmd_add(int argc, const char **argv, const char *prefix)
 	die_in_unpopulated_submodule(the_repository->index, prefix);
 	die_path_inside_submodule(the_repository->index, &pathspec);
 
-	enable_fscache(1);
+	enable_fscache(0);
 	/* We do not really re-read the index but update the up-to-date flags */
 	preload_index(the_repository->index, &pathspec, 0);
 
diff --git a/builtin/checkout.c b/builtin/checkout.c
index e19edfc0507f2f..44db2bae72a2f5 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -403,7 +403,7 @@ static int checkout_worktree(const struct checkout_opts *opts,
 	if (pc_workers > 1)
 		init_parallel_checkout();
 
-	enable_fscache(1);
+	enable_fscache(the_repository->index->cache_nr);
 	for (pos = 0; pos < the_repository->index->cache_nr; pos++) {
 		struct cache_entry *ce = the_repository->index->cache[pos];
 		if (ce->ce_flags & CE_MATCHED) {
@@ -429,7 +429,7 @@ static int checkout_worktree(const struct checkout_opts *opts,
 		errs |= run_parallel_checkout(&state, pc_workers, pc_threshold,
 					      NULL, NULL);
 	mem_pool_discard(&ce_mem_pool, should_validate_cache_entries());
-	enable_fscache(0);
+	disable_fscache();
 	remove_marked_cache_entries(the_repository->index, 1);
 	remove_scheduled_dirs();
 	errs |= finish_delayed_checkout(&state, opts->show_progress);
diff --git a/builtin/commit.c b/builtin/commit.c
index 1f61c538faf84e..6a5266075a8ede 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -1568,7 +1568,7 @@ int cmd_status(int argc, const char **argv, const char *prefix)
 		       PATHSPEC_PREFER_FULL,
 		       prefix, argv);
 
-	enable_fscache(1);
+	enable_fscache(0);
 	if (status_format != STATUS_FORMAT_PORCELAIN &&
 	    status_format != STATUS_FORMAT_PORCELAIN_V2)
 		progress_flag = REFRESH_PROGRESS;
@@ -1609,7 +1609,7 @@ int cmd_status(int argc, const char **argv, const char *prefix)
 	wt_status_print(&s);
 	wt_status_collect_free_buffers(&s);
 
-	enable_fscache(0);
+	disable_fscache();
 	return 0;
 }
 
diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index 0f0225981ef4a4..bb485fad483ccf 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -405,7 +405,7 @@ static struct fsentry *fscache_get(struct fsentry *key)
  * Enables or disables the cache. Note that the cache is read-only, changes to
  * the working directory are NOT reflected in the cache while enabled.
  */
-int fscache_enable(int enable)
+int fscache_enable(int enable, size_t initial_size)
 {
 	int result;
 
@@ -421,7 +421,11 @@ int fscache_enable(int enable)
 		InitializeCriticalSection(&mutex);
 		lstat_requests = opendir_requests = 0;
 		fscache_misses = fscache_requests = 0;
-		hashmap_init(&map, (hashmap_cmp_fn) fsentry_cmp, NULL, 0);
+		/*
+		 * avoid having to rehash by leaving room for the parent dirs.
+		 * '4' was determined empirically by testing several repos
+		 */
+		hashmap_init(&map, (hashmap_cmp_fn) fsentry_cmp, NULL, initial_size * 4);
 		initialized = 1;
 	}
 
diff --git a/compat/win32/fscache.h b/compat/win32/fscache.h
index 2f06f8df97dcd0..d49c9381114da6 100644
--- a/compat/win32/fscache.h
+++ b/compat/win32/fscache.h
@@ -1,8 +1,9 @@
 #ifndef FSCACHE_H
 #define FSCACHE_H
 
-int fscache_enable(int enable);
-#define enable_fscache(x) fscache_enable(x)
+int fscache_enable(int enable, size_t initial_size);
+#define enable_fscache(initial_size) fscache_enable(1, initial_size)
+#define disable_fscache() fscache_enable(0, 0)
 
 int fscache_enabled(const char *path);
 #define is_fscache_enabled(path) fscache_enabled(path)
diff --git a/fetch-pack.c b/fetch-pack.c
index 89279c73d6b05b..0af92b55882bfc 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -757,7 +757,7 @@ static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 	save_commit_buffer = 0;
 
 	trace2_region_enter("fetch-pack", "parse_remote_refs_and_find_cutoff", NULL);
-	enable_fscache(1);
+	enable_fscache(0);
 	for (ref = *refs; ref; ref = ref->next) {
 		struct commit *commit;
 
@@ -784,7 +784,7 @@ static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 		if (!cutoff || cutoff < commit->date)
 			cutoff = commit->date;
 	}
-	enable_fscache(0);
+	disable_fscache();
 	trace2_region_leave("fetch-pack", "parse_remote_refs_and_find_cutoff", NULL);
 
 	/*
diff --git a/git-compat-util.h b/git-compat-util.h
index 529ab6a9834f7f..7c5a95bc55403e 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1537,6 +1537,10 @@ static inline int is_missing_file_error(int errno_)
 #define enable_fscache(x) /* noop */
 #endif
 
+#ifndef disable_fscache
+#define disable_fscache() /* noop */
+#endif
+
 #ifndef is_fscache_enabled
 #define is_fscache_enabled(path) (0)
 #endif
diff --git a/preload-index.c b/preload-index.c
index ec1d7b46d55fc0..93f74d44e2a023 100644
--- a/preload-index.c
+++ b/preload-index.c
@@ -132,7 +132,7 @@ void preload_index(struct index_state *index,
 		pthread_mutex_init(&pd.mutex, NULL);
 	}
 
-	enable_fscache(1);
+	enable_fscache(index->cache_nr);
 	for (i = 0; i < threads; i++) {
 		struct thread_data *p = data+i;
 		int err;
@@ -169,7 +169,7 @@ void preload_index(struct index_state *index,
 	trace2_data_intmax("index", NULL, "preload/sum_lstat", t2_sum_lstat);
 	trace2_region_leave("index", "preload", NULL);
 
-	enable_fscache(0);
+	disable_fscache();
 }
 
 int repo_read_index_preload(struct repository *repo,
diff --git a/read-cache.c b/read-cache.c
index 009343eda25273..33ae3c30b68728 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -1530,7 +1530,7 @@ int refresh_index(struct index_state *istate, unsigned int flags,
 	typechange_fmt = in_porcelain ? "T\t%s\n" : "%s: needs update\n";
 	added_fmt      = in_porcelain ? "A\t%s\n" : "%s: needs update\n";
 	unmerged_fmt   = in_porcelain ? "U\t%s\n" : "%s: needs merge\n";
-	enable_fscache(1);
+	enable_fscache(0);
 	/*
 	 * Use the multi-threaded preload_index() to refresh most of the
 	 * cache entries quickly then in the single threaded loop below,
@@ -1625,7 +1625,7 @@ int refresh_index(struct index_state *istate, unsigned int flags,
 	display_progress(progress, istate->cache_nr);
 	stop_progress(&progress);
 	trace_performance_leave("refresh index");
-	enable_fscache(0);
+	disable_fscache();
 	return has_errors;
 }
 

From db35cf553884bfe4f2c5aa7ea9910919a85d7577 Mon Sep 17 00:00:00 2001
From: Ben Peart <benpeart@microsoft.com>
Date: Thu, 4 Oct 2018 15:38:08 -0400
Subject: [PATCH 165/259] fscache: update fscache to be thread specific instead
 of global

The threading model for fscache has been to have a single, global cache.
This puts requirements on it to be thread safe so that callers like
preload-index can call it from multiple threads.  This was implemented
with a single mutex and completion events which introduces contention
between the calling threads.

Simplify the threading model by making fscache thread specific.  This allows
us to remove the global mutex and synchronization events entirely and instead
associate a fscache with every thread that requests one. This works well with
the current multi-threading which divides the cache entries into blocks with
a separate thread processing each block.

At the end of each worker thread, if there is a fscache on the primary
thread, merge the cached results from the worker into the primary thread
cache. This enables us to reuse the cache later especially when scanning for
untracked files.

In testing, this reduced the time spent in preload_index() by about 25% and
also reduced the CPU utilization significantly.  On a repo with ~200K files,
it reduced overall status times by ~12%.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
---
 compat/win32/fscache.c | 294 +++++++++++++++++++++++++----------------
 compat/win32/fscache.h |  22 ++-
 git-compat-util.h      |  12 ++
 preload-index.c        |   8 +-
 4 files changed, 215 insertions(+), 121 deletions(-)

diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index bb485fad483ccf..b2513e6932e1e1 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -7,14 +7,24 @@
 #include "../../trace.h"
 #include "config.h"
 
-static int initialized;
-static volatile long enabled;
-static struct hashmap map;
+static volatile long initialized;
+static DWORD dwTlsIndex;
 static CRITICAL_SECTION mutex;
-static unsigned int lstat_requests;
-static unsigned int opendir_requests;
-static unsigned int fscache_requests;
-static unsigned int fscache_misses;
+
+/*
+ * Store one fscache per thread to avoid thread contention and locking.
+ * This is ok because multi-threaded access is 1) uncommon and 2) always
+ * splitting up the cache entries across multiple threads so there isn't
+ * any overlap between threads anyway.
+ */
+struct fscache {
+	volatile long enabled;
+	struct hashmap map;
+	unsigned int lstat_requests;
+	unsigned int opendir_requests;
+	unsigned int fscache_requests;
+	unsigned int fscache_misses;
+};
 static struct trace_key trace_fscache = TRACE_KEY_INIT(FSCACHE);
 
 /*
@@ -34,8 +44,6 @@ struct fsentry {
 	union {
 		/* Reference count of the directory listing. */
 		volatile long refcnt;
-		/* Handle to wait on the loading thread. */
-		HANDLE hwait;
 		struct {
 			/* More stat members (only used for file entries). */
 			off64_t st_size;
@@ -253,86 +261,63 @@ static struct fsentry *fsentry_create_list(const struct fsentry *dir,
 /*
  * Adds a directory listing to the cache.
  */
-static void fscache_add(struct fsentry *fse)
+static void fscache_add(struct fscache *cache, struct fsentry *fse)
 {
 	if (fse->list)
 		fse = fse->list;
 
 	for (; fse; fse = fse->next)
-		hashmap_add(&map, &fse->ent);
+		hashmap_add(&cache->map, &fse->ent);
 }
 
 /*
  * Clears the cache.
  */
-static void fscache_clear(void)
+static void fscache_clear(struct fscache *cache)
 {
-	hashmap_clear_and_free(&map, struct fsentry, ent);
-	hashmap_init(&map, (hashmap_cmp_fn)fsentry_cmp, NULL, 0);
-	lstat_requests = opendir_requests = 0;
-	fscache_misses = fscache_requests = 0;
+	hashmap_clear_and_free(&cache->map, struct fsentry, ent);
+	hashmap_init(&cache->map, (hashmap_cmp_fn)fsentry_cmp, NULL, 0);
+	cache->lstat_requests = cache->opendir_requests = 0;
+	cache->fscache_misses = cache->fscache_requests = 0;
 }
 
 /*
  * Checks if the cache is enabled for the given path.
  */
-int fscache_enabled(const char *path)
+static int do_fscache_enabled(struct fscache *cache, const char *path)
 {
-	return enabled > 0 && !is_absolute_path(path);
+	return cache->enabled > 0 && !is_absolute_path(path);
 }
 
-/*
- * Looks up a cache entry, waits if its being loaded by another thread.
- * The mutex must be owned by the calling thread.
- */
-static struct fsentry *fscache_get_wait(struct fsentry *key)
+int fscache_enabled(const char *path)
 {
-	struct fsentry *fse = hashmap_get_entry(&map, key, ent, NULL);
-
-	/* return if its a 'real' entry (future entries have refcnt == 0) */
-	if (!fse || fse->list || fse->u.refcnt)
-		return fse;
-
-	/* create an event and link our key to the future entry */
-	key->u.hwait = CreateEvent(NULL, TRUE, FALSE, NULL);
-	key->next = fse->next;
-	fse->next = key;
-
-	/* wait for the loading thread to signal us */
-	LeaveCriticalSection(&mutex);
-	WaitForSingleObject(key->u.hwait, INFINITE);
-	CloseHandle(key->u.hwait);
-	EnterCriticalSection(&mutex);
+	struct fscache *cache = fscache_getcache();
 
-	/* repeat cache lookup */
-	return hashmap_get_entry(&map, key, ent, NULL);
+	return cache ? do_fscache_enabled(cache, path) : 0;
 }
 
 /*
  * Looks up or creates a cache entry for the specified key.
  */
-static struct fsentry *fscache_get(struct fsentry *key)
+static struct fsentry *fscache_get(struct fscache *cache, struct fsentry *key)
 {
-	struct fsentry *fse, *future, *waiter;
+	struct fsentry *fse;
 	int dir_not_found;
 
-	EnterCriticalSection(&mutex);
-	fscache_requests++;
+	cache->fscache_requests++;
 	/* check if entry is in cache */
-	fse = fscache_get_wait(key);
+	fse = hashmap_get_entry(&cache->map, key, ent, NULL);
 	if (fse) {
 		if (fse->st_mode)
 			fsentry_addref(fse);
 		else
 			fse = NULL; /* non-existing directory */
-		LeaveCriticalSection(&mutex);
 		return fse;
 	}
 	/* if looking for a file, check if directory listing is in cache */
 	if (!fse && key->list) {
-		fse = fscache_get_wait(key->list);
+		fse = hashmap_get_entry(&cache->map, key->list, ent, NULL);
 		if (fse) {
-			LeaveCriticalSection(&mutex);
 			/*
 			 * dir entry without file entry, or dir does not
 			 * exist -> file doesn't exist
@@ -342,25 +327,8 @@ static struct fsentry *fscache_get(struct fsentry *key)
 		}
 	}
 
-	/* add future entry to indicate that we're loading it */
-	future = key->list ? key->list : key;
-	future->next = NULL;
-	future->u.refcnt = 0;
-	hashmap_add(&map, &future->ent);
-
-	/* create the directory listing (outside mutex!) */
-	LeaveCriticalSection(&mutex);
-	fse = fsentry_create_list(future, &dir_not_found);
-	EnterCriticalSection(&mutex);
-
-	/* remove future entry and signal waiting threads */
-	hashmap_remove(&map, &future->ent, NULL);
-	waiter = future->next;
-	while (waiter) {
-		HANDLE h = waiter->u.hwait;
-		waiter = waiter->next;
-		SetEvent(h);
-	}
+	/* create the directory listing */
+	fse = fsentry_create_list(key->list ? key->list : key, &dir_not_found);
 
 	/* leave on error (errno set by fsentry_create_list) */
 	if (!fse) {
@@ -374,19 +342,18 @@ static struct fsentry *fscache_get(struct fsentry *key)
 					    key->list->dirent.d_name,
 					    key->list->len);
 			fse->st_mode = 0;
-			hashmap_add(&map, &fse->ent);
+			hashmap_add(&cache->map, &fse->ent);
 		}
-		LeaveCriticalSection(&mutex);
 		return NULL;
 	}
 
 	/* add directory listing to the cache */
-	fscache_misses++;
-	fscache_add(fse);
+	cache->fscache_misses++;
+	fscache_add(cache, fse);
 
 	/* lookup file entry if requested (fse already points to directory) */
 	if (key->list)
-		fse = hashmap_get_entry(&map, key, ent, NULL);
+		fse = hashmap_get_entry(&cache->map, key, ent, NULL);
 
 	if (fse && !fse->st_mode)
 		fse = NULL; /* non-existing directory */
@@ -397,59 +364,104 @@ static struct fsentry *fscache_get(struct fsentry *key)
 	else
 		errno = ENOENT;
 
-	LeaveCriticalSection(&mutex);
 	return fse;
 }
 
 /*
- * Enables or disables the cache. Note that the cache is read-only, changes to
+ * Enables the cache. Note that the cache is read-only, changes to
  * the working directory are NOT reflected in the cache while enabled.
  */
-int fscache_enable(int enable, size_t initial_size)
+int fscache_enable(size_t initial_size)
 {
-	int result;
+	int fscache;
+	struct fscache *cache;
+	int result = 0;
+
+	/* allow the cache to be disabled entirely */
+	fscache = git_env_bool("GIT_TEST_FSCACHE", -1);
+	if (fscache != -1)
+		core_fscache = fscache;
+	if (!core_fscache)
+		return 0;
 
+	/*
+	 * refcount the global fscache initialization so that the
+	 * opendir and lstat function pointers are redirected if
+	 * any threads are using the fscache.
+	 */
 	if (!initialized) {
-		int fscache = git_env_bool("GIT_TEST_FSCACHE", -1);
-
-		/* allow the cache to be disabled entirely */
-		if (fscache != -1)
-			core_fscache = fscache;
-		if (!core_fscache)
-			return 0;
-
 		InitializeCriticalSection(&mutex);
-		lstat_requests = opendir_requests = 0;
-		fscache_misses = fscache_requests = 0;
+		if (!dwTlsIndex) {
+			dwTlsIndex = TlsAlloc();
+			if (dwTlsIndex == TLS_OUT_OF_INDEXES) {
+				LeaveCriticalSection(&mutex);
+				return 0;
+			}
+		}
+
+		/* redirect opendir and lstat to the fscache implementations */
+		opendir = fscache_opendir;
+		lstat = fscache_lstat;
+	}
+	InterlockedIncrement(&initialized);
+
+	/* refcount the thread specific initialization */
+	cache = fscache_getcache();
+	if (cache) {
+		InterlockedIncrement(&cache->enabled);
+	} else {
+		cache = (struct fscache *)xcalloc(1, sizeof(*cache));
+		cache->enabled = 1;
 		/*
 		 * avoid having to rehash by leaving room for the parent dirs.
 		 * '4' was determined empirically by testing several repos
 		 */
-		hashmap_init(&map, (hashmap_cmp_fn) fsentry_cmp, NULL, initial_size * 4);
-		initialized = 1;
+		hashmap_init(&cache->map, (hashmap_cmp_fn)fsentry_cmp, NULL, initial_size * 4);
+		if (!TlsSetValue(dwTlsIndex, cache))
+			BUG("TlsSetValue error");
 	}
 
-	result = enable ? InterlockedIncrement(&enabled)
-			: InterlockedDecrement(&enabled);
+	trace_printf_key(&trace_fscache, "fscache: enable\n");
+	return result;
+}
 
-	if (enable && result == 1) {
-		/* redirect opendir and lstat to the fscache implementations */
-		opendir = fscache_opendir;
-		lstat = fscache_lstat;
-	} else if (!enable && !result) {
+/*
+ * Disables the cache.
+ */
+void fscache_disable(void)
+{
+	struct fscache *cache;
+
+	if (!core_fscache)
+		return;
+
+	/* update the thread specific fscache initialization */
+	cache = fscache_getcache();
+	if (!cache)
+		BUG("fscache_disable() called on a thread where fscache has not been initialized");
+	if (!cache->enabled)
+		BUG("fscache_disable() called on an fscache that is already disabled");
+	InterlockedDecrement(&cache->enabled);
+	if (!cache->enabled) {
+		TlsSetValue(dwTlsIndex, NULL);
+		trace_printf_key(&trace_fscache, "fscache_disable: lstat %u, opendir %u, "
+			"total requests/misses %u/%u\n",
+			cache->lstat_requests, cache->opendir_requests,
+			cache->fscache_requests, cache->fscache_misses);
+		fscache_clear(cache);
+		free(cache);
+	}
+
+	/* update the global fscache initialization */
+	InterlockedDecrement(&initialized);
+	if (!initialized) {
 		/* reset opendir and lstat to the original implementations */
 		opendir = dirent_opendir;
 		lstat = mingw_lstat;
-		EnterCriticalSection(&mutex);
-		trace_printf_key(&trace_fscache, "fscache: lstat %u, opendir %u, "
-						 "total requests/misses %u/%u\n",
-				lstat_requests, opendir_requests,
-				fscache_requests, fscache_misses);
-		fscache_clear();
-		LeaveCriticalSection(&mutex);
 	}
-	trace_printf_key(&trace_fscache, "fscache: enable(%d)\n", enable);
-	return result;
+
+	trace_printf_key(&trace_fscache, "fscache: disable\n");
+	return;
 }
 
 /*
@@ -457,10 +469,10 @@ int fscache_enable(int enable, size_t initial_size)
  */
 void fscache_flush(void)
 {
-	if (enabled) {
-		EnterCriticalSection(&mutex);
-		fscache_clear();
-		LeaveCriticalSection(&mutex);
+	struct fscache *cache = fscache_getcache();
+
+	if (cache && cache->enabled) {
+		fscache_clear(cache);
 	}
 }
 
@@ -473,11 +485,12 @@ int fscache_lstat(const char *filename, struct stat *st)
 	int dirlen, base, len;
 	struct heap_fsentry key[2];
 	struct fsentry *fse;
+	struct fscache *cache = fscache_getcache();
 
-	if (!fscache_enabled(filename))
+	if (!cache || !do_fscache_enabled(cache, filename))
 		return mingw_lstat(filename, st);
 
-	lstat_requests++;
+	cache->lstat_requests++;
 	/* split filename into path + name */
 	len = strlen(filename);
 	if (len && is_dir_sep(filename[len - 1]))
@@ -490,7 +503,7 @@ int fscache_lstat(const char *filename, struct stat *st)
 	/* lookup entry for path + name in cache */
 	fsentry_init(&key[0].u.ent, NULL, filename, dirlen);
 	fsentry_init(&key[1].u.ent, &key[0].u.ent, filename + base, len - base);
-	fse = fscache_get(&key[1].u.ent);
+	fse = fscache_get(cache, &key[1].u.ent);
 	if (!fse) {
 		errno = ENOENT;
 		return -1;
@@ -555,11 +568,12 @@ DIR *fscache_opendir(const char *dirname)
 	struct fsentry *list;
 	fscache_DIR *dir;
 	int len;
+	struct fscache *cache = fscache_getcache();
 
-	if (!fscache_enabled(dirname))
+	if (!cache || !do_fscache_enabled(cache, dirname))
 		return dirent_opendir(dirname);
 
-	opendir_requests++;
+	cache->opendir_requests++;
 	/* prepare name (strip trailing '/', replace '.') */
 	len = strlen(dirname);
 	if ((len == 1 && dirname[0] == '.') ||
@@ -568,7 +582,7 @@ DIR *fscache_opendir(const char *dirname)
 
 	/* get directory listing from cache */
 	fsentry_init(&key.u.ent, NULL, dirname, len);
-	list = fscache_get(&key.u.ent);
+	list = fscache_get(cache, &key.u.ent);
 	if (!list)
 		return NULL;
 
@@ -579,3 +593,53 @@ DIR *fscache_opendir(const char *dirname)
 	dir->pfsentry = list;
 	return (DIR*) dir;
 }
+
+struct fscache *fscache_getcache(void)
+{
+	return (struct fscache *)TlsGetValue(dwTlsIndex);
+}
+
+void fscache_merge(struct fscache *dest)
+{
+	struct hashmap_iter iter;
+	struct hashmap_entry *e;
+	struct fscache *cache = fscache_getcache();
+
+	/*
+	 * Only do the merge if fscache was enabled and we have a dest
+	 * cache to merge into.
+	 */
+	if (!dest) {
+		fscache_enable(0);
+		return;
+	}
+	if (!cache)
+		BUG("fscache_merge() called on a thread where fscache has not been initialized");
+
+	TlsSetValue(dwTlsIndex, NULL);
+	trace_printf_key(&trace_fscache, "fscache_merge: lstat %u, opendir %u, "
+		"total requests/misses %u/%u\n",
+		cache->lstat_requests, cache->opendir_requests,
+		cache->fscache_requests, cache->fscache_misses);
+
+	/*
+	 * This is only safe because the primary thread we're merging into
+	 * isn't being used so the critical section only needs to prevent
+	 * the the child threads from stomping on each other.
+	 */
+	EnterCriticalSection(&mutex);
+
+	hashmap_iter_init(&cache->map, &iter);
+	while ((e = hashmap_iter_next(&iter)))
+		hashmap_add(&dest->map, e);
+
+	dest->lstat_requests += cache->lstat_requests;
+	dest->opendir_requests += cache->opendir_requests;
+	dest->fscache_requests += cache->fscache_requests;
+	dest->fscache_misses += cache->fscache_misses;
+	LeaveCriticalSection(&mutex);
+
+	free(cache);
+
+	InterlockedDecrement(&initialized);
+}
diff --git a/compat/win32/fscache.h b/compat/win32/fscache.h
index d49c9381114da6..2eb8bf3f5cfee8 100644
--- a/compat/win32/fscache.h
+++ b/compat/win32/fscache.h
@@ -1,9 +1,16 @@
 #ifndef FSCACHE_H
 #define FSCACHE_H
 
-int fscache_enable(int enable, size_t initial_size);
-#define enable_fscache(initial_size) fscache_enable(1, initial_size)
-#define disable_fscache() fscache_enable(0, 0)
+/*
+ * The fscache is thread specific. enable_fscache() must be called
+ * for each thread where caching is desired.
+ */
+
+int fscache_enable(size_t initial_size);
+#define enable_fscache(initial_size) fscache_enable(initial_size)
+
+void fscache_disable(void);
+#define disable_fscache() fscache_disable()
 
 int fscache_enabled(const char *path);
 #define is_fscache_enabled(path) fscache_enabled(path)
@@ -14,4 +21,13 @@ void fscache_flush(void);
 DIR *fscache_opendir(const char *dir);
 int fscache_lstat(const char *file_name, struct stat *buf);
 
+/* opaque fscache structure */
+struct fscache;
+
+struct fscache *fscache_getcache(void);
+#define getcache_fscache() fscache_getcache()
+
+void fscache_merge(struct fscache *dest);
+#define merge_fscache(dest) fscache_merge(dest)
+
 #endif
diff --git a/git-compat-util.h b/git-compat-util.h
index 7c5a95bc55403e..c9b4513c124b5a 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1533,6 +1533,10 @@ static inline int is_missing_file_error(int errno_)
  * data or even file content without the need to synchronize with the file
  * system.
  */
+
+ /* opaque fscache structure */
+struct fscache;
+
 #ifndef enable_fscache
 #define enable_fscache(x) /* noop */
 #endif
@@ -1549,6 +1553,14 @@ static inline int is_missing_file_error(int errno_)
 #define flush_fscache() /* noop */
 #endif
 
+#ifndef getcache_fscache
+#define getcache_fscache() (NULL) /* noop */
+#endif
+
+#ifndef merge_fscache
+#define merge_fscache(dest) /* noop */
+#endif
+
 int cmd_main(int, const char **);
 
 /*
diff --git a/preload-index.c b/preload-index.c
index 93f74d44e2a023..24bb9d0e1ded61 100644
--- a/preload-index.c
+++ b/preload-index.c
@@ -16,6 +16,8 @@
 #include "symlinks.h"
 #include "trace2.h"
 
+static struct fscache *fscache;
+
 /*
  * Mostly randomly chosen maximum thread counts: we
  * cap the parallelism to 20 threads, and we want
@@ -53,6 +55,7 @@ static void *preload_thread(void *_data)
 		nr = index->cache_nr - p->offset;
 	last_nr = nr;
 
+	enable_fscache(nr);
 	do {
 		struct cache_entry *ce = *cep++;
 		struct stat st;
@@ -96,6 +99,7 @@ static void *preload_thread(void *_data)
 		pthread_mutex_unlock(&pd->mutex);
 	}
 	cache_def_clear(&cache);
+	merge_fscache(fscache);
 	return NULL;
 }
 
@@ -111,6 +115,7 @@ void preload_index(struct index_state *index,
 	if (!HAVE_THREADS || !core_preload_index)
 		return;
 
+	fscache = getcache_fscache();
 	threads = index->cache_nr / THREAD_COST;
 	if ((index->cache_nr > 1) && (threads < 2) && git_env_bool("GIT_TEST_PRELOAD_INDEX", 0))
 		threads = 2;
@@ -132,7 +137,6 @@ void preload_index(struct index_state *index,
 		pthread_mutex_init(&pd.mutex, NULL);
 	}
 
-	enable_fscache(index->cache_nr);
 	for (i = 0; i < threads; i++) {
 		struct thread_data *p = data+i;
 		int err;
@@ -168,8 +172,6 @@ void preload_index(struct index_state *index,
 
 	trace2_data_intmax("index", NULL, "preload/sum_lstat", t2_sum_lstat);
 	trace2_region_leave("index", "preload", NULL);
-
-	disable_fscache();
 }
 
 int repo_read_index_preload(struct repository *repo,

From 57d95da75fe6200c6cd4316cfd19899ec8fe8d8c Mon Sep 17 00:00:00 2001
From: Ben Peart <benpeart@microsoft.com>
Date: Tue, 25 Sep 2018 16:28:16 -0400
Subject: [PATCH 166/259] fscache: add fscache hit statistics

Track fscache hits and misses for lstat and opendir requests.  Reporting of
statistics is done when the cache is disabled for the last time and freed
and is only reported if GIT_TRACE_FSCACHE is set.

Sample output is:

11:33:11.836428 compat/win32/fscache.c:433 fscache: lstat 3775, opendir 263, total requests/misses 4052/269

Signed-off-by: Ben Peart <benpeart@microsoft.com>
---
 compat/win32/fscache.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index 029c1fb1693911..0f0225981ef4a4 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -11,6 +11,10 @@ static int initialized;
 static volatile long enabled;
 static struct hashmap map;
 static CRITICAL_SECTION mutex;
+static unsigned int lstat_requests;
+static unsigned int opendir_requests;
+static unsigned int fscache_requests;
+static unsigned int fscache_misses;
 static struct trace_key trace_fscache = TRACE_KEY_INIT(FSCACHE);
 
 /*
@@ -265,6 +269,8 @@ static void fscache_clear(void)
 {
 	hashmap_clear_and_free(&map, struct fsentry, ent);
 	hashmap_init(&map, (hashmap_cmp_fn)fsentry_cmp, NULL, 0);
+	lstat_requests = opendir_requests = 0;
+	fscache_misses = fscache_requests = 0;
 }
 
 /*
@@ -311,6 +317,7 @@ static struct fsentry *fscache_get(struct fsentry *key)
 	int dir_not_found;
 
 	EnterCriticalSection(&mutex);
+	fscache_requests++;
 	/* check if entry is in cache */
 	fse = fscache_get_wait(key);
 	if (fse) {
@@ -374,6 +381,7 @@ static struct fsentry *fscache_get(struct fsentry *key)
 	}
 
 	/* add directory listing to the cache */
+	fscache_misses++;
 	fscache_add(fse);
 
 	/* lookup file entry if requested (fse already points to directory) */
@@ -411,6 +419,8 @@ int fscache_enable(int enable)
 			return 0;
 
 		InitializeCriticalSection(&mutex);
+		lstat_requests = opendir_requests = 0;
+		fscache_misses = fscache_requests = 0;
 		hashmap_init(&map, (hashmap_cmp_fn) fsentry_cmp, NULL, 0);
 		initialized = 1;
 	}
@@ -427,6 +437,10 @@ int fscache_enable(int enable)
 		opendir = dirent_opendir;
 		lstat = mingw_lstat;
 		EnterCriticalSection(&mutex);
+		trace_printf_key(&trace_fscache, "fscache: lstat %u, opendir %u, "
+						 "total requests/misses %u/%u\n",
+				lstat_requests, opendir_requests,
+				fscache_requests, fscache_misses);
 		fscache_clear();
 		LeaveCriticalSection(&mutex);
 	}
@@ -459,6 +473,7 @@ int fscache_lstat(const char *filename, struct stat *st)
 	if (!fscache_enabled(filename))
 		return mingw_lstat(filename, st);
 
+	lstat_requests++;
 	/* split filename into path + name */
 	len = strlen(filename);
 	if (len && is_dir_sep(filename[len - 1]))
@@ -540,6 +555,7 @@ DIR *fscache_opendir(const char *dirname)
 	if (!fscache_enabled(dirname))
 		return dirent_opendir(dirname);
 
+	opendir_requests++;
 	/* prepare name (strip trailing '/', replace '.') */
 	len = strlen(dirname);
 	if ((len == 1 && dirname[0] == '.') ||

From ea247692fb8ca961fcf0c96289b33a7d134e62f2 Mon Sep 17 00:00:00 2001
From: Ben Peart <benpeart@microsoft.com>
Date: Fri, 2 Nov 2018 11:19:10 -0400
Subject: [PATCH 167/259] fscache: teach fscache to use mempool

Now that the fscache is single threaded, take advantage of the mem_pool as
the allocator to significantly reduce the cost of allocations and frees.

With the reduced cost of free, in future patches, we can start freeing the
fscache at the end of commands instead of just leaking it.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/win32/fscache.c | 45 ++++++++++++++++++++++--------------------
 1 file changed, 24 insertions(+), 21 deletions(-)

diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index b2513e6932e1e1..61181004d8ebf5 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -6,6 +6,7 @@
 #include "../../abspath.h"
 #include "../../trace.h"
 #include "config.h"
+#include "../../mem-pool.h"
 
 static volatile long initialized;
 static DWORD dwTlsIndex;
@@ -20,6 +21,7 @@ static CRITICAL_SECTION mutex;
 struct fscache {
 	volatile long enabled;
 	struct hashmap map;
+	struct mem_pool mem_pool;
 	unsigned int lstat_requests;
 	unsigned int opendir_requests;
 	unsigned int fscache_requests;
@@ -124,11 +126,12 @@ static void fsentry_init(struct fsentry *fse, struct fsentry *list,
 /*
  * Allocate an fsentry structure on the heap.
  */
-static struct fsentry *fsentry_alloc(struct fsentry *list, const char *name,
+static struct fsentry *fsentry_alloc(struct fscache *cache, struct fsentry *list, const char *name,
 		size_t len)
 {
 	/* overallocate fsentry and copy the name to the end */
-	struct fsentry *fse = xmalloc(sizeof(struct fsentry) + len + 1);
+	struct fsentry *fse =
+		mem_pool_alloc(&cache->mem_pool, sizeof(*fse) + len + 1);
 	/* init the rest of the structure */
 	fsentry_init(fse, list, name, len);
 	fse->next = NULL;
@@ -148,27 +151,21 @@ inline static void fsentry_addref(struct fsentry *fse)
 }
 
 /*
- * Release the reference to an fsentry, frees the memory if its the last ref.
+ * Release the reference to an fsentry.
  */
 static void fsentry_release(struct fsentry *fse)
 {
 	if (fse->list)
 		fse = fse->list;
 
-	if (InterlockedDecrement(&(fse->u.refcnt)))
-		return;
-
-	while (fse) {
-		struct fsentry *next = fse->next;
-		free(fse);
-		fse = next;
-	}
+	InterlockedDecrement(&(fse->u.refcnt));
 }
 
 /*
  * Allocate and initialize an fsentry from a WIN32_FIND_DATA structure.
  */
-static struct fsentry *fseentry_create_entry(struct fsentry *list,
+static struct fsentry *fseentry_create_entry(struct fscache *cache,
+					     struct fsentry *list,
 					     const WIN32_FIND_DATAW *fdata)
 {
 	char buf[MAX_PATH * 3];
@@ -176,7 +173,7 @@ static struct fsentry *fseentry_create_entry(struct fsentry *list,
 	struct fsentry *fse;
 	len = xwcstoutf(buf, fdata->cFileName, ARRAY_SIZE(buf));
 
-	fse = fsentry_alloc(list, buf, len);
+	fse = fsentry_alloc(cache, list, buf, len);
 
 	fse->st_mode = file_attr_to_st_mode(fdata->dwFileAttributes);
 	fse->dirent.d_type = S_ISDIR(fse->st_mode) ? DT_DIR : DT_REG;
@@ -194,7 +191,7 @@ static struct fsentry *fseentry_create_entry(struct fsentry *list,
  * Dir should not contain trailing '/'. Use an empty string for the current
  * directory (not "."!).
  */
-static struct fsentry *fsentry_create_list(const struct fsentry *dir,
+static struct fsentry *fsentry_create_list(struct fscache *cache, const struct fsentry *dir,
 					   int *dir_not_found)
 {
 	wchar_t pattern[MAX_PATH + 2]; /* + 2 for '/' '*' */
@@ -233,14 +230,14 @@ static struct fsentry *fsentry_create_list(const struct fsentry *dir,
 	}
 
 	/* allocate object to hold directory listing */
-	list = fsentry_alloc(NULL, dir->dirent.d_name, dir->len);
+	list = fsentry_alloc(cache, NULL, dir->dirent.d_name, dir->len);
 	list->st_mode = S_IFDIR;
 	list->dirent.d_type = DT_DIR;
 
 	/* walk directory and build linked list of fsentry structures */
 	phead = &list->next;
 	do {
-		*phead = fseentry_create_entry(list, &fdata);
+		*phead = fseentry_create_entry(cache, list, &fdata);
 		phead = &(*phead)->next;
 	} while (FindNextFileW(h, &fdata));
 
@@ -252,7 +249,7 @@ static struct fsentry *fsentry_create_list(const struct fsentry *dir,
 	if (err == ERROR_NO_MORE_FILES)
 		return list;
 
-	/* otherwise free the list and return error */
+	/* otherwise release the list and return error */
 	fsentry_release(list);
 	errno = err_win_to_posix(err);
 	return NULL;
@@ -275,7 +272,9 @@ static void fscache_add(struct fscache *cache, struct fsentry *fse)
  */
 static void fscache_clear(struct fscache *cache)
 {
-	hashmap_clear_and_free(&cache->map, struct fsentry, ent);
+	mem_pool_discard(&cache->mem_pool, 0);
+	mem_pool_init(&cache->mem_pool, 0);
+	hashmap_clear(&cache->map);
 	hashmap_init(&cache->map, (hashmap_cmp_fn)fsentry_cmp, NULL, 0);
 	cache->lstat_requests = cache->opendir_requests = 0;
 	cache->fscache_misses = cache->fscache_requests = 0;
@@ -328,7 +327,7 @@ static struct fsentry *fscache_get(struct fscache *cache, struct fsentry *key)
 	}
 
 	/* create the directory listing */
-	fse = fsentry_create_list(key->list ? key->list : key, &dir_not_found);
+	fse = fsentry_create_list(cache, key->list ? key->list : key, &dir_not_found);
 
 	/* leave on error (errno set by fsentry_create_list) */
 	if (!fse) {
@@ -338,7 +337,7 @@ static struct fsentry *fscache_get(struct fscache *cache, struct fsentry *key)
 			 * empty, which for all practical matters is the same
 			 * thing as far as fscache is concerned).
 			 */
-			fse = fsentry_alloc(key->list->list,
+			fse = fsentry_alloc(cache, key->list->list,
 					    key->list->dirent.d_name,
 					    key->list->len);
 			fse->st_mode = 0;
@@ -417,6 +416,7 @@ int fscache_enable(size_t initial_size)
 		 * '4' was determined empirically by testing several repos
 		 */
 		hashmap_init(&cache->map, (hashmap_cmp_fn)fsentry_cmp, NULL, initial_size * 4);
+		mem_pool_init(&cache->mem_pool, 0);
 		if (!TlsSetValue(dwTlsIndex, cache))
 			BUG("TlsSetValue error");
 	}
@@ -448,7 +448,8 @@ void fscache_disable(void)
 			"total requests/misses %u/%u\n",
 			cache->lstat_requests, cache->opendir_requests,
 			cache->fscache_requests, cache->fscache_misses);
-		fscache_clear(cache);
+		mem_pool_discard(&cache->mem_pool, 0);
+		hashmap_clear(&cache->map);
 		free(cache);
 	}
 
@@ -633,6 +634,8 @@ void fscache_merge(struct fscache *dest)
 	while ((e = hashmap_iter_next(&iter)))
 		hashmap_add(&dest->map, e);
 
+	mem_pool_combine(&dest->mem_pool, &cache->mem_pool);
+
 	dest->lstat_requests += cache->lstat_requests;
 	dest->opendir_requests += cache->opendir_requests;
 	dest->fscache_requests += cache->fscache_requests;

From e01925b12db748ea31e65c50c6e50c87fd9c1a1a Mon Sep 17 00:00:00 2001
From: Ben Peart <benpeart@microsoft.com>
Date: Fri, 16 Nov 2018 10:59:18 -0500
Subject: [PATCH 168/259] fscache: make fscache_enable() thread safe

The recent change to make fscache thread specific relied on fscache_enable()
being called first from the primary thread before being called in parallel
from worker threads.  Make that more robust and protect it with a critical
section to avoid any issues.

Helped-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Ben Peart <benpeart@microsoft.com>
---
 compat/mingw.c         |  4 ++++
 compat/win32/fscache.c | 23 +++++++++++++----------
 compat/win32/fscache.h |  2 ++
 3 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index ca8b116190b3af..75d9e79de68f21 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -21,6 +21,7 @@
 #include <sspi.h>
 #include "../write-or-die.h"
 #include "../repository.h"
+#include "win32/fscache.h"
 
 #define HCAST(type, handle) ((type)(intptr_t)handle)
 
@@ -3490,6 +3491,9 @@ int wmain(int argc, const wchar_t **wargv)
 	/* initialize critical section for waitpid pinfo_t list */
 	InitializeCriticalSection(&pinfo_cs);
 
+	/* initialize critical section for fscache */
+	InitializeCriticalSection(&fscache_cs);
+
 	/* set up default file mode and file modes for stdin/out/err */
 	_fmode = _O_BINARY;
 	_setmode(_fileno(stdin), _O_BINARY);
diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index 61181004d8ebf5..a07decbb435246 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -10,7 +10,7 @@
 
 static volatile long initialized;
 static DWORD dwTlsIndex;
-static CRITICAL_SECTION mutex;
+CRITICAL_SECTION fscache_cs;
 
 /*
  * Store one fscache per thread to avoid thread contention and locking.
@@ -388,12 +388,12 @@ int fscache_enable(size_t initial_size)
 	 * opendir and lstat function pointers are redirected if
 	 * any threads are using the fscache.
 	 */
+	EnterCriticalSection(&fscache_cs);
 	if (!initialized) {
-		InitializeCriticalSection(&mutex);
 		if (!dwTlsIndex) {
 			dwTlsIndex = TlsAlloc();
 			if (dwTlsIndex == TLS_OUT_OF_INDEXES) {
-				LeaveCriticalSection(&mutex);
+				LeaveCriticalSection(&fscache_cs);
 				return 0;
 			}
 		}
@@ -402,12 +402,13 @@ int fscache_enable(size_t initial_size)
 		opendir = fscache_opendir;
 		lstat = fscache_lstat;
 	}
-	InterlockedIncrement(&initialized);
+	initialized++;
+	LeaveCriticalSection(&fscache_cs);
 
 	/* refcount the thread specific initialization */
 	cache = fscache_getcache();
 	if (cache) {
-		InterlockedIncrement(&cache->enabled);
+		cache->enabled++;
 	} else {
 		cache = (struct fscache *)xcalloc(1, sizeof(*cache));
 		cache->enabled = 1;
@@ -441,7 +442,7 @@ void fscache_disable(void)
 		BUG("fscache_disable() called on a thread where fscache has not been initialized");
 	if (!cache->enabled)
 		BUG("fscache_disable() called on an fscache that is already disabled");
-	InterlockedDecrement(&cache->enabled);
+	cache->enabled--;
 	if (!cache->enabled) {
 		TlsSetValue(dwTlsIndex, NULL);
 		trace_printf_key(&trace_fscache, "fscache_disable: lstat %u, opendir %u, "
@@ -454,12 +455,14 @@ void fscache_disable(void)
 	}
 
 	/* update the global fscache initialization */
-	InterlockedDecrement(&initialized);
+	EnterCriticalSection(&fscache_cs);
+	initialized--;
 	if (!initialized) {
 		/* reset opendir and lstat to the original implementations */
 		opendir = dirent_opendir;
 		lstat = mingw_lstat;
 	}
+	LeaveCriticalSection(&fscache_cs);
 
 	trace_printf_key(&trace_fscache, "fscache: disable\n");
 	return;
@@ -628,7 +631,7 @@ void fscache_merge(struct fscache *dest)
 	 * isn't being used so the critical section only needs to prevent
 	 * the the child threads from stomping on each other.
 	 */
-	EnterCriticalSection(&mutex);
+	EnterCriticalSection(&fscache_cs);
 
 	hashmap_iter_init(&cache->map, &iter);
 	while ((e = hashmap_iter_next(&iter)))
@@ -640,9 +643,9 @@ void fscache_merge(struct fscache *dest)
 	dest->opendir_requests += cache->opendir_requests;
 	dest->fscache_requests += cache->fscache_requests;
 	dest->fscache_misses += cache->fscache_misses;
-	LeaveCriticalSection(&mutex);
+	initialized--;
+	LeaveCriticalSection(&fscache_cs);
 
 	free(cache);
 
-	InterlockedDecrement(&initialized);
 }
diff --git a/compat/win32/fscache.h b/compat/win32/fscache.h
index 2eb8bf3f5cfee8..042b247a542554 100644
--- a/compat/win32/fscache.h
+++ b/compat/win32/fscache.h
@@ -6,6 +6,8 @@
  * for each thread where caching is desired.
  */
 
+extern CRITICAL_SECTION fscache_cs;
+
 int fscache_enable(size_t initial_size);
 #define enable_fscache(initial_size) fscache_enable(initial_size)
 

From 302c46d34f0a561f6bec3362eddf15ce0010b281 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 20 Sep 2017 21:52:28 +0200
Subject: [PATCH 169/259] git-gui--askyesno: fix funny text wrapping

The text wrapping seems to be aligned to the right side of the Yes
button, leaving an awful lot of empty space.

Let's try to counter this by using pixel units.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 git-gui/git-gui--askyesno | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/git-gui/git-gui--askyesno b/git-gui/git-gui--askyesno
index 2a6e6fd11122f5..cf9c990d0919b3 100755
--- a/git-gui/git-gui--askyesno
+++ b/git-gui/git-gui--askyesno
@@ -20,8 +20,8 @@ if {$argc < 1} {
 }
 
 ${NS}::frame .t
-${NS}::label .t.m -text $prompt -justify center -width 40
-.t.m configure -wraplength 400
+${NS}::label .t.m -text $prompt -justify center -width 400px
+.t.m configure -wraplength 400px
 pack .t.m -side top -fill x -padx 20 -pady 20 -expand 1
 pack .t -side top -fill x -ipadx 20 -ipady 20 -expand 1
 

From a39b0cb161238e549d1bb7baae99a03d92d3e466 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 11 Dec 2018 12:59:29 +0100
Subject: [PATCH 170/259] fscache: remember the reparse tag for each entry

We will use this in the next commit to implement an FSCache-aware
version of is_mount_point().

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/win32/fscache.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index be701880743224..4e550e4811757e 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -46,6 +46,7 @@ static struct trace_key trace_fscache = TRACE_KEY_INIT(FSCACHE);
 struct fsentry {
 	struct hashmap_entry ent;
 	mode_t st_mode;
+	ULONG reparse_tag;
 	/* Pointer to the directory listing, or NULL for the listing itself. */
 	struct fsentry *list;
 	/* Pointer to the next file entry of the list. */
@@ -197,6 +198,10 @@ static struct fsentry *fseentry_create_entry(struct fscache *cache,
 
 	fse = fsentry_alloc(cache, list, buf, len);
 
+	fse->reparse_tag =
+		fdata->FileAttributes & FILE_ATTRIBUTE_REPARSE_POINT ?
+		fdata->EaSize : 0;
+
 	fse->st_mode = file_attr_to_st_mode(fdata->FileAttributes);
 	fse->dirent.d_type = S_ISDIR(fse->st_mode) ? DT_DIR : DT_REG;
 	fse->u.s.st_size = fdata->EndOfFile.LowPart |

From 614b54a01ae3767803a127bd532d36319d74cfbe Mon Sep 17 00:00:00 2001
From: Heiko Voigt <hvoigt@hvoigt.net>
Date: Sun, 21 Feb 2010 21:05:04 +0100
Subject: [PATCH 171/259] git-gui: provide question helper for retry fallback
 on Windows

Make use of the new environment variable GIT_ASK_YESNO to support the
recently implemented fallback in case unlink, rename or rmdir fail for
files in use on Windows. The added dialog will present a yes/no question
to the the user which will currently be used by the windows compat layer
to let the user retry a failed file operation.

Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
---
 git-gui/Makefile          |  2 ++
 git-gui/git-gui--askyesno | 51 +++++++++++++++++++++++++++++++++++++++
 git-gui/git-gui.sh        |  3 +++
 3 files changed, 56 insertions(+)
 create mode 100755 git-gui/git-gui--askyesno

diff --git a/git-gui/Makefile b/git-gui/Makefile
index 667c39ed564a55..39a330efb67469 100644
--- a/git-gui/Makefile
+++ b/git-gui/Makefile
@@ -280,6 +280,7 @@ install: all
 	$(QUIET)$(INSTALL_D0)'$(DESTDIR_SQ)$(gitexecdir_SQ)' $(INSTALL_D1)
 	$(QUIET)$(INSTALL_X0)git-gui $(INSTALL_X1) '$(DESTDIR_SQ)$(gitexecdir_SQ)'
 	$(QUIET)$(INSTALL_X0)git-gui--askpass $(INSTALL_X1) '$(DESTDIR_SQ)$(gitexecdir_SQ)'
+	$(QUIET)$(INSTALL_X0)git-gui--askyesno $(INSTALL_X1) '$(DESTDIR_SQ)$(gitexecdir_SQ)'
 	$(QUIET)$(foreach p,$(GITGUI_BUILT_INS), $(INSTALL_L0)'$(DESTDIR_SQ)$(gitexecdir_SQ)/$p' $(INSTALL_L1)'$(DESTDIR_SQ)$(gitexecdir_SQ)/git-gui' $(INSTALL_L2)'$(DESTDIR_SQ)$(gitexecdir_SQ)/$p' $(INSTALL_L3) &&) true
 ifdef GITGUI_WINDOWS_WRAPPER
 	$(QUIET)$(INSTALL_R0)git-gui.tcl $(INSTALL_R1) '$(DESTDIR_SQ)$(gitexecdir_SQ)'
@@ -298,6 +299,7 @@ uninstall:
 	$(QUIET)$(CLEAN_DST) '$(DESTDIR_SQ)$(gitexecdir_SQ)'
 	$(QUIET)$(REMOVE_F0)'$(DESTDIR_SQ)$(gitexecdir_SQ)'/git-gui $(REMOVE_F1)
 	$(QUIET)$(REMOVE_F0)'$(DESTDIR_SQ)$(gitexecdir_SQ)'/git-gui--askpass $(REMOVE_F1)
+	$(QUIET)$(REMOVE_F0)'$(DESTDIR_SQ)$(gitexecdir_SQ)'/git-gui--askyesno $(REMOVE_F1)
 	$(QUIET)$(foreach p,$(GITGUI_BUILT_INS), $(REMOVE_F0)'$(DESTDIR_SQ)$(gitexecdir_SQ)'/$p $(REMOVE_F1) &&) true
 ifdef GITGUI_WINDOWS_WRAPPER
 	$(QUIET)$(REMOVE_F0)'$(DESTDIR_SQ)$(gitexecdir_SQ)'/git-gui.tcl $(REMOVE_F1)
diff --git a/git-gui/git-gui--askyesno b/git-gui/git-gui--askyesno
new file mode 100755
index 00000000000000..2a6e6fd11122f5
--- /dev/null
+++ b/git-gui/git-gui--askyesno
@@ -0,0 +1,51 @@
+#!/bin/sh
+# Tcl ignores the next line -*- tcl -*- \
+exec wish "$0" -- "$@"
+
+# This is an implementation of a simple yes no dialog
+# which is injected into the git commandline by git gui
+# in case a yesno question needs to be answered.
+
+set NS {}
+set use_ttk [package vsatisfies [package provide Tk] 8.5]
+if {$use_ttk} {
+	set NS ttk
+}
+
+if {$argc < 1} {
+	puts stderr "Usage: $argv0 <question>"
+	exit 1
+} else {
+	set prompt [join $argv " "]
+}
+
+${NS}::frame .t
+${NS}::label .t.m -text $prompt -justify center -width 40
+.t.m configure -wraplength 400
+pack .t.m -side top -fill x -padx 20 -pady 20 -expand 1
+pack .t -side top -fill x -ipadx 20 -ipady 20 -expand 1
+
+${NS}::frame .b
+${NS}::frame .b.left -width 200
+${NS}::button .b.yes -text Yes -command yes
+${NS}::button .b.no  -text No  -command no
+
+
+pack .b.left -side left -expand 1 -fill x
+pack .b.yes -side left -expand 1
+pack .b.no -side right -expand 1 -ipadx 5
+pack .b -side bottom -fill x -ipadx 20 -ipady 15
+
+bind . <Key-Return> {exit 0}
+bind . <Key-Escape> {exit 1}
+
+proc no {} {
+	exit 1
+}
+
+proc yes {} {
+	exit 0
+}
+
+wm title . "Question?"
+tk::PlaceWindow .
diff --git a/git-gui/git-gui.sh b/git-gui/git-gui.sh
index 514b7192a0640e..c8d8e1e2caef99 100755
--- a/git-gui/git-gui.sh
+++ b/git-gui/git-gui.sh
@@ -1248,6 +1248,9 @@ set have_tk85 [expr {[package vcompare $tk_version "8.5"] >= 0}]
 if {![info exists env(SSH_ASKPASS)]} {
 	set env(SSH_ASKPASS) [gitexec git-gui--askpass]
 }
+if {![info exists env(GIT_ASK_YESNO)]} {
+	set env(GIT_ASK_YESNO) [gitexec git-gui--askyesno]
+}
 
 ######################################################################
 ##

From bb4a2c14d6a32cf4f925b5f591c0a576eb213f10 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 20 Sep 2017 21:53:45 +0200
Subject: [PATCH 172/259] git-gui--askyesno: allow overriding the window title

"Question?" is maybe not the most informative thing to ask. In the
absence of better information, it is the best we can do, of course.

However, Git for Windows' auto updater just learned the trick to use
git-gui--askyesno to ask the user whether to update now or not. And in
this scripted scenario, we can easily pass a command-line option to
change the window title.

So let's support that with the new `--title <title>` option.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 git-gui/git-gui--askyesno | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/git-gui/git-gui--askyesno b/git-gui/git-gui--askyesno
index cf9c990d0919b3..45b0260eff8145 100755
--- a/git-gui/git-gui--askyesno
+++ b/git-gui/git-gui--askyesno
@@ -12,10 +12,15 @@ if {$use_ttk} {
 	set NS ttk
 }
 
+set title "Question?"
 if {$argc < 1} {
 	puts stderr "Usage: $argv0 <question>"
 	exit 1
 } else {
+	if {$argc > 2 && [lindex $argv 0] == "--title"} {
+		set title [lindex $argv 1]
+		set argv [lreplace $argv 0 1]
+	}
 	set prompt [join $argv " "]
 }
 
@@ -47,5 +52,5 @@ proc yes {} {
 	exit 0
 }
 
-wm title . "Question?"
+wm title . $title
 tk::PlaceWindow .

From 0275f968519badbd5d9282ef941d8a5aeab65009 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 11 Dec 2018 12:17:49 +0100
Subject: [PATCH 173/259] fscache: implement an FSCache-aware is_mount_point()

When FSCache is active, we can cache the reparse tag and use it directly
to determine whether a path refers to an NTFS junction, without any
additional, costly I/O.

Note: this change only makes a difference with the next commit, which
will make use of the FSCache in `git clean` (contingent on
`core.fscache` set, of course).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c         |  2 ++
 compat/mingw.h         |  3 ++-
 compat/win32/fscache.c | 35 +++++++++++++++++++++++++++++++++++
 compat/win32/fscache.h |  1 +
 4 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 75d9e79de68f21..c1ca68aab11a6a 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2778,6 +2778,8 @@ pid_t waitpid(pid_t pid, int *status, int options)
 	return -1;
 }
 
+int (*win32_is_mount_point)(struct strbuf *path) = mingw_is_mount_point;
+
 int mingw_is_mount_point(struct strbuf *path)
 {
 	WIN32_FIND_DATAW findbuf = { 0 };
diff --git a/compat/mingw.h b/compat/mingw.h
index 946ff707327b4e..97cdb8d51631ea 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -476,7 +476,8 @@ static inline void convert_slashes(char *path)
 }
 struct strbuf;
 int mingw_is_mount_point(struct strbuf *path);
-#define is_mount_point mingw_is_mount_point
+extern int (*win32_is_mount_point)(struct strbuf *path);
+#define is_mount_point win32_is_mount_point
 #define CAN_UNLINK_MOUNT_POINTS 1
 #define PATH_SEP ';'
 char *mingw_query_user_email(void);
diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index 4e550e4811757e..da19ba0994de58 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -469,6 +469,7 @@ int fscache_enable(size_t initial_size)
 		/* redirect opendir and lstat to the fscache implementations */
 		opendir = fscache_opendir;
 		lstat = fscache_lstat;
+		win32_is_mount_point = fscache_is_mount_point;
 	}
 	initialized++;
 	LeaveCriticalSection(&fscache_cs);
@@ -529,6 +530,7 @@ void fscache_disable(void)
 		/* reset opendir and lstat to the original implementations */
 		opendir = dirent_opendir;
 		lstat = mingw_lstat;
+		win32_is_mount_point = mingw_is_mount_point;
 	}
 	LeaveCriticalSection(&fscache_cs);
 
@@ -599,6 +601,39 @@ int fscache_lstat(const char *filename, struct stat *st)
 	return 0;
 }
 
+/*
+ * is_mount_point() replacement, uses cache if enabled, otherwise falls
+ * back to mingw_is_mount_point().
+ */
+int fscache_is_mount_point(struct strbuf *path)
+{
+	int dirlen, base, len;
+	struct heap_fsentry key[2];
+	struct fsentry *fse;
+	struct fscache *cache = fscache_getcache();
+
+	if (!cache || !do_fscache_enabled(cache, path->buf))
+		return mingw_is_mount_point(path);
+
+	cache->lstat_requests++;
+	/* split path into path + name */
+	len = path->len;
+	if (len && is_dir_sep(path->buf[len - 1]))
+		len--;
+	base = len;
+	while (base && !is_dir_sep(path->buf[base - 1]))
+		base--;
+	dirlen = base ? base - 1 : 0;
+
+	/* lookup entry for path + name in cache */
+	fsentry_init(&key[0].u.ent, NULL, path->buf, dirlen);
+	fsentry_init(&key[1].u.ent, &key[0].u.ent, path->buf + base, len - base);
+	fse = fscache_get(cache, &key[1].u.ent);
+	if (!fse)
+		return mingw_is_mount_point(path);
+	return fse->reparse_tag == IO_REPARSE_TAG_MOUNT_POINT;
+}
+
 typedef struct fscache_DIR {
 	struct DIR base_dir; /* extend base struct DIR */
 	struct fsentry *pfsentry;
diff --git a/compat/win32/fscache.h b/compat/win32/fscache.h
index 042b247a542554..386c770a85d321 100644
--- a/compat/win32/fscache.h
+++ b/compat/win32/fscache.h
@@ -22,6 +22,7 @@ void fscache_flush(void);
 
 DIR *fscache_opendir(const char *dir);
 int fscache_lstat(const char *file_name, struct stat *buf);
+int fscache_is_mount_point(struct strbuf *path);
 
 /* opaque fscache structure */
 struct fscache;

From 9014b9b4acb6e8a0dd9daae4b4765011cdf86656 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sat, 4 Feb 2012 21:54:36 +0100
Subject: [PATCH 174/259] gitk: Unicode file name support

Assumes file names in git tree objects are UTF-8 encoded.

On most unix systems, the system encoding (and thus the TCL system
encoding) will be UTF-8, so file names will be displayed correctly.

On Windows, it is impossible to set the system encoding to UTF-8.
Changing the TCL system encoding (via 'encoding system ...', e.g. in the
startup code) is explicitly discouraged by the TCL docs.

Change gitk functions dealing with file names to always convert
from and to UTF-8.

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 gitk-git/gitk | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/gitk-git/gitk b/gitk-git/gitk
index 076ca3687d7653..a792f48e5a1a47 100755
--- a/gitk-git/gitk
+++ b/gitk-git/gitk
@@ -7847,7 +7847,7 @@ proc gettreeline {gtf id} {
         if {[string index $fname 0] eq "\""} {
             set fname [lindex $fname 0]
         }
-        set fname [encoding convertfrom $fname]
+        set fname [encoding convertfrom utf-8 $fname]
         lappend treefilelist($id) $fname
     }
     if {![eof $gtf]} {
@@ -8109,7 +8109,7 @@ proc gettreediffline {gdtf ids} {
             if {[string index $file 0] eq "\""} {
                 set file [lindex $file 0]
             }
-            set file [encoding convertfrom $file]
+            set file [encoding convertfrom utf-8 $file]
             if {$file ne [lindex $treediff end]} {
                 lappend treediff $file
                 lappend sublist $file
@@ -8254,7 +8254,7 @@ proc makediffhdr {fname ids} {
     global ctext curdiffstart treediffs diffencoding
     global ctext_file_names jump_to_here targetline diffline
 
-    set fname [encoding convertfrom $fname]
+    set fname [encoding convertfrom utf-8 $fname]
     set diffencoding [get_path_encoding $fname]
     set i [lsearch -exact $treediffs($ids) $fname]
     if {$i >= 0} {
@@ -8316,7 +8316,7 @@ proc parseblobdiffline {ids line} {
 
     if {![string compare -length 5 "diff " $line]} {
         if {![regexp {^diff (--cc|--git) } $line m type]} {
-            set line [encoding convertfrom $line]
+            set line [encoding convertfrom utf-8 $line]
             $ctext insert end "$line\n" hunksep
             continue
         }
@@ -8365,7 +8365,7 @@ proc parseblobdiffline {ids line} {
         makediffhdr $fname $ids
 
     } elseif {![string compare -length 16 "* Unmerged path " $line]} {
-        set fname [encoding convertfrom [string range $line 16 end]]
+        set fname [encoding convertfrom utf-8 [string range $line 16 end]]
         $ctext insert end "\n"
         set curdiffstart [$ctext index "end - 1c"]
         lappend ctext_file_names $fname
@@ -8418,7 +8418,7 @@ proc parseblobdiffline {ids line} {
             if {[string index $fname 0] eq "\""} {
                 set fname [lindex $fname 0]
             }
-            set fname [encoding convertfrom $fname]
+            set fname [encoding convertfrom utf-8 $fname]
             set i [lsearch -exact $treediffs($ids) $fname]
             if {$i >= 0} {
                 setinlist difffilestart $i $curdiffstart
@@ -8437,6 +8437,7 @@ proc parseblobdiffline {ids line} {
             set diffinhdr 0
             return
         }
+        set line [encoding convertfrom utf-8 $line]
         $ctext insert end "$line\n" filesep
 
     } else {
@@ -12405,7 +12406,7 @@ proc cache_gitattr {attr pathlist} {
             foreach row [split $rlist "\n"] {
                 if {[regexp "(.*): $attr: (.*)" $row m path value]} {
                     if {[string index $path 0] eq "\""} {
-                        set path [encoding convertfrom [lindex $path 0]]
+                        set path [encoding convertfrom utf-8 [lindex $path 0]]
                     }
                     set path_attr_cache($attr,$path) $value
                 }

From 55a60a1b2abf12219e40b18d13677635aaed78b6 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 23 Jul 2010 18:06:05 +0200
Subject: [PATCH 175/259] git gui: set GIT_ASKPASS=git-gui--askpass if not set
 yet

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 git-gui/git-gui.sh | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/git-gui/git-gui.sh b/git-gui/git-gui.sh
index c8d8e1e2caef99..434fd9d844accc 100755
--- a/git-gui/git-gui.sh
+++ b/git-gui/git-gui.sh
@@ -1248,6 +1248,9 @@ set have_tk85 [expr {[package vcompare $tk_version "8.5"] >= 0}]
 if {![info exists env(SSH_ASKPASS)]} {
 	set env(SSH_ASKPASS) [gitexec git-gui--askpass]
 }
+if {![info exists env(GIT_ASKPASS)]} {
+	set env(GIT_ASKPASS) [gitexec git-gui--askpass]
+}
 if {![info exists env(GIT_ASK_YESNO)]} {
 	set env(GIT_ASK_YESNO) [gitexec git-gui--askyesno]
 }

From c5d45353a2ec3ef28901466b03de13fdd19b896b Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 20 Sep 2017 21:55:45 +0200
Subject: [PATCH 176/259] git-gui--askyesno (mingw): use Git for Windows' icon,
 if available

For additional GUI goodness.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 git-gui/git-gui--askyesno | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/git-gui/git-gui--askyesno b/git-gui/git-gui--askyesno
index 45b0260eff8145..c0c82e7cbd01d6 100755
--- a/git-gui/git-gui--askyesno
+++ b/git-gui/git-gui--askyesno
@@ -52,5 +52,17 @@ proc yes {} {
 	exit 0
 }
 
+if {$::tcl_platform(platform) eq {windows}} {
+	set icopath [file dirname [file normalize $argv0]]
+	if {[file tail $icopath] eq {git-core}} {
+		set icopath [file dirname $icopath]
+	}
+	set icopath [file dirname $icopath]
+	set icopath [file join $icopath share git git-for-windows.ico]
+	if {[file exists $icopath]} {
+		wm iconbitmap . -default $icopath
+	}
+}
+
 wm title . $title
 tk::PlaceWindow .

From f0ac73802d349a3607f02a84d1011b139cbbad59 Mon Sep 17 00:00:00 2001
From: Ben Peart <benpeart@microsoft.com>
Date: Thu, 15 Nov 2018 14:15:40 -0500
Subject: [PATCH 177/259] fscache: teach fscache to use NtQueryDirectoryFile

Using FindFirstFileExW() requires the OS to allocate a 64K buffer for each
directory and then free it when we call FindClose().  Update fscache to call
the underlying kernel API NtQueryDirectoryFile so that we can do the buffer
management ourselves.  That allows us to allocate a single buffer for the
lifetime of the cache and reuse it for each directory.

This change improves performance of 'git status' by 18% in a repo with ~200K
files and 30k folders.

Documentation for NtQueryDirectoryFile can be found at:

https://docs.microsoft.com/en-us/windows-hardware/drivers/ddi/content/ntifs/nf-ntifs-ntquerydirectoryfile
https://docs.microsoft.com/en-us/windows/desktop/FileIO/file-attribute-constants
https://docs.microsoft.com/en-us/windows/desktop/fileio/reparse-point-tags

To determine if the specified directory is a symbolic link, inspect the
FileAttributes member to see if the FILE_ATTRIBUTE_REPARSE_POINT flag is
set. If so, EaSize will contain the reparse tag (this is a so far
undocumented feature, but confirmed by the NTFS developers). To
determine if the reparse point is a symbolic link (and not some other
form of reparse point), test whether the tag value equals the value
IO_REPARSE_TAG_SYMLINK.

The NtQueryDirectoryFile() call works best (and on Windows 8.1 and
earlier, it works *only*) with buffer sizes up to 64kB. Which is 32k
wide characters, so let's use that as our buffer size.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/win32/fscache.c | 123 ++++++++++++++++++++++++++++----------
 compat/win32/ntifs.h   | 131 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 224 insertions(+), 30 deletions(-)
 create mode 100644 compat/win32/ntifs.h

diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index a07decbb435246..be701880743224 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -7,6 +7,7 @@
 #include "../../trace.h"
 #include "config.h"
 #include "../../mem-pool.h"
+#include "ntifs.h"
 
 static volatile long initialized;
 static DWORD dwTlsIndex;
@@ -26,6 +27,13 @@ struct fscache {
 	unsigned int opendir_requests;
 	unsigned int fscache_requests;
 	unsigned int fscache_misses;
+	/*
+	 * 32k wide characters translates to 64kB, which is the maximum that
+	 * Windows 8.1 and earlier can handle. On network drives, not only
+	 * the client's Windows version matters, but also the server's,
+	 * therefore we need to keep this to 64kB.
+	 */
+	WCHAR buffer[32 * 1024];
 };
 static struct trace_key trace_fscache = TRACE_KEY_INIT(FSCACHE);
 
@@ -161,27 +169,44 @@ static void fsentry_release(struct fsentry *fse)
 	InterlockedDecrement(&(fse->u.refcnt));
 }
 
+static int xwcstoutfn(char *utf, int utflen, const wchar_t *wcs, int wcslen)
+{
+	if (!wcs || !utf || utflen < 1) {
+		errno = EINVAL;
+		return -1;
+	}
+	utflen = WideCharToMultiByte(CP_UTF8, 0, wcs, wcslen, utf, utflen, NULL, NULL);
+	if (utflen)
+		return utflen;
+	errno = ERANGE;
+	return -1;
+}
+
 /*
- * Allocate and initialize an fsentry from a WIN32_FIND_DATA structure.
+ * Allocate and initialize an fsentry from a FILE_FULL_DIR_INFORMATION structure.
  */
 static struct fsentry *fseentry_create_entry(struct fscache *cache,
 					     struct fsentry *list,
-					     const WIN32_FIND_DATAW *fdata)
+					     PFILE_FULL_DIR_INFORMATION fdata)
 {
 	char buf[MAX_PATH * 3];
 	int len;
 	struct fsentry *fse;
-	len = xwcstoutf(buf, fdata->cFileName, ARRAY_SIZE(buf));
+
+	len = xwcstoutfn(buf, ARRAY_SIZE(buf), fdata->FileName, fdata->FileNameLength / sizeof(wchar_t));
 
 	fse = fsentry_alloc(cache, list, buf, len);
 
-	fse->st_mode = file_attr_to_st_mode(fdata->dwFileAttributes);
+	fse->st_mode = file_attr_to_st_mode(fdata->FileAttributes);
 	fse->dirent.d_type = S_ISDIR(fse->st_mode) ? DT_DIR : DT_REG;
-	fse->u.s.st_size = (((off64_t) (fdata->nFileSizeHigh)) << 32)
-			| fdata->nFileSizeLow;
-	filetime_to_timespec(&(fdata->ftLastAccessTime), &(fse->u.s.st_atim));
-	filetime_to_timespec(&(fdata->ftLastWriteTime), &(fse->u.s.st_mtim));
-	filetime_to_timespec(&(fdata->ftCreationTime), &(fse->u.s.st_ctim));
+	fse->u.s.st_size = fdata->EndOfFile.LowPart |
+		(((off_t)fdata->EndOfFile.HighPart) << 32);
+	filetime_to_timespec((FILETIME *)&(fdata->LastAccessTime),
+			     &(fse->u.s.st_atim));
+	filetime_to_timespec((FILETIME *)&(fdata->LastWriteTime),
+			     &(fse->u.s.st_mtim));
+	filetime_to_timespec((FILETIME *)&(fdata->CreationTime),
+			     &(fse->u.s.st_ctim));
 
 	return fse;
 }
@@ -194,8 +219,10 @@ static struct fsentry *fseentry_create_entry(struct fscache *cache,
 static struct fsentry *fsentry_create_list(struct fscache *cache, const struct fsentry *dir,
 					   int *dir_not_found)
 {
-	wchar_t pattern[MAX_PATH + 2]; /* + 2 for '/' '*' */
-	WIN32_FIND_DATAW fdata;
+	wchar_t pattern[MAX_PATH];
+	NTSTATUS status;
+	IO_STATUS_BLOCK iosb;
+	PFILE_FULL_DIR_INFORMATION di;
 	HANDLE h;
 	int wlen;
 	struct fsentry *list, **phead;
@@ -211,15 +238,18 @@ static struct fsentry *fsentry_create_list(struct fscache *cache, const struct f
 		return NULL;
 	}
 
-	/* append optional '/' and wildcard '*' */
-	if (wlen)
-		pattern[wlen++] = '/';
-	pattern[wlen++] = '*';
-	pattern[wlen] = 0;
+	/* handle CWD */
+	if (!wlen) {
+		wlen = GetCurrentDirectoryW(ARRAY_SIZE(pattern), pattern);
+		if (!wlen || wlen >= ARRAY_SIZE(pattern)) {
+			errno = wlen ? ENAMETOOLONG : err_win_to_posix(GetLastError());
+			return NULL;
+		}
+	}
 
-	/* open find handle */
-	h = FindFirstFileExW(pattern, FindExInfoBasic, &fdata, FindExSearchNameMatch,
-		NULL, FIND_FIRST_EX_LARGE_FETCH);
+	h = CreateFileW(pattern, FILE_LIST_DIRECTORY,
+		FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
+		NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
 	if (h == INVALID_HANDLE_VALUE) {
 		err = GetLastError();
 		*dir_not_found = 1; /* or empty directory */
@@ -236,22 +266,55 @@ static struct fsentry *fsentry_create_list(struct fscache *cache, const struct f
 
 	/* walk directory and build linked list of fsentry structures */
 	phead = &list->next;
-	do {
-		*phead = fseentry_create_entry(cache, list, &fdata);
+	status = NtQueryDirectoryFile(h, NULL, 0, 0, &iosb, cache->buffer,
+		sizeof(cache->buffer), FileFullDirectoryInformation, FALSE, NULL, FALSE);
+	if (!NT_SUCCESS(status)) {
+		/*
+		 * NtQueryDirectoryFile returns STATUS_INVALID_PARAMETER when
+		 * asked to enumerate an invalid directory (ie it is a file
+		 * instead of a directory).  Verify that is the actual cause
+		 * of the error.
+		*/
+		if (status == STATUS_INVALID_PARAMETER) {
+			DWORD attributes = GetFileAttributesW(pattern);
+			if (!(attributes & FILE_ATTRIBUTE_DIRECTORY))
+				status = ERROR_DIRECTORY;
+		}
+		goto Error;
+	}
+	di = (PFILE_FULL_DIR_INFORMATION)(cache->buffer);
+	for (;;) {
+
+		*phead = fseentry_create_entry(cache, list, di);
 		phead = &(*phead)->next;
-	} while (FindNextFileW(h, &fdata));
 
-	/* remember result of last FindNextFile, then close find handle */
-	err = GetLastError();
-	FindClose(h);
+		/* If there is no offset in the entry, the buffer has been exhausted. */
+		if (di->NextEntryOffset == 0) {
+			status = NtQueryDirectoryFile(h, NULL, 0, 0, &iosb, cache->buffer,
+				sizeof(cache->buffer), FileFullDirectoryInformation, FALSE, NULL, FALSE);
+			if (!NT_SUCCESS(status)) {
+				if (status == STATUS_NO_MORE_FILES)
+					break;
+				goto Error;
+			}
+
+			di = (PFILE_FULL_DIR_INFORMATION)(cache->buffer);
+			continue;
+		}
+
+		/* Advance to the next entry. */
+		di = (PFILE_FULL_DIR_INFORMATION)(((PUCHAR)di) + di->NextEntryOffset);
+	}
 
-	/* return the list if we've got all the files */
-	if (err == ERROR_NO_MORE_FILES)
-		return list;
+	CloseHandle(h);
+	return list;
 
-	/* otherwise release the list and return error */
+Error:
+	trace_printf_key(&trace_fscache,
+			 "fscache: status(%ld) unable to query directory "
+			 "contents '%s'\n", status, dir->dirent.d_name);
+	CloseHandle(h);
 	fsentry_release(list);
-	errno = err_win_to_posix(err);
 	return NULL;
 }
 
diff --git a/compat/win32/ntifs.h b/compat/win32/ntifs.h
new file mode 100644
index 00000000000000..64ed792c52f352
--- /dev/null
+++ b/compat/win32/ntifs.h
@@ -0,0 +1,131 @@
+#ifndef _NTIFS_
+#define _NTIFS_
+
+/*
+ * Copy necessary structures and definitions out of the Windows DDK
+ * to enable calling NtQueryDirectoryFile()
+ */
+
+typedef _Return_type_success_(return >= 0) LONG NTSTATUS;
+#define NT_SUCCESS(Status)  (((NTSTATUS)(Status)) >= 0)
+
+#if !defined(_NTSECAPI_) && !defined(_WINTERNL_) && \
+	!defined(__UNICODE_STRING_DEFINED)
+#define __UNICODE_STRING_DEFINED
+typedef struct _UNICODE_STRING {
+	USHORT Length;
+	USHORT MaximumLength;
+	PWSTR Buffer;
+} UNICODE_STRING;
+typedef UNICODE_STRING *PUNICODE_STRING;
+typedef const UNICODE_STRING *PCUNICODE_STRING;
+#endif /* !_NTSECAPI_ && !_WINTERNL_ && !__UNICODE_STRING_DEFINED */
+
+typedef enum _FILE_INFORMATION_CLASS {
+	FileDirectoryInformation = 1,
+	FileFullDirectoryInformation,
+	FileBothDirectoryInformation,
+	FileBasicInformation,
+	FileStandardInformation,
+	FileInternalInformation,
+	FileEaInformation,
+	FileAccessInformation,
+	FileNameInformation,
+	FileRenameInformation,
+	FileLinkInformation,
+	FileNamesInformation,
+	FileDispositionInformation,
+	FilePositionInformation,
+	FileFullEaInformation,
+	FileModeInformation,
+	FileAlignmentInformation,
+	FileAllInformation,
+	FileAllocationInformation,
+	FileEndOfFileInformation,
+	FileAlternateNameInformation,
+	FileStreamInformation,
+	FilePipeInformation,
+	FilePipeLocalInformation,
+	FilePipeRemoteInformation,
+	FileMailslotQueryInformation,
+	FileMailslotSetInformation,
+	FileCompressionInformation,
+	FileObjectIdInformation,
+	FileCompletionInformation,
+	FileMoveClusterInformation,
+	FileQuotaInformation,
+	FileReparsePointInformation,
+	FileNetworkOpenInformation,
+	FileAttributeTagInformation,
+	FileTrackingInformation,
+	FileIdBothDirectoryInformation,
+	FileIdFullDirectoryInformation,
+	FileValidDataLengthInformation,
+	FileShortNameInformation,
+	FileIoCompletionNotificationInformation,
+	FileIoStatusBlockRangeInformation,
+	FileIoPriorityHintInformation,
+	FileSfioReserveInformation,
+	FileSfioVolumeInformation,
+	FileHardLinkInformation,
+	FileProcessIdsUsingFileInformation,
+	FileNormalizedNameInformation,
+	FileNetworkPhysicalNameInformation,
+	FileIdGlobalTxDirectoryInformation,
+	FileIsRemoteDeviceInformation,
+	FileAttributeCacheInformation,
+	FileNumaNodeInformation,
+	FileStandardLinkInformation,
+	FileRemoteProtocolInformation,
+	FileMaximumInformation
+} FILE_INFORMATION_CLASS, *PFILE_INFORMATION_CLASS;
+
+typedef struct _FILE_FULL_DIR_INFORMATION {
+	ULONG NextEntryOffset;
+	ULONG FileIndex;
+	LARGE_INTEGER CreationTime;
+	LARGE_INTEGER LastAccessTime;
+	LARGE_INTEGER LastWriteTime;
+	LARGE_INTEGER ChangeTime;
+	LARGE_INTEGER EndOfFile;
+	LARGE_INTEGER AllocationSize;
+	ULONG FileAttributes;
+	ULONG FileNameLength;
+	ULONG EaSize;
+	WCHAR FileName[1];
+} FILE_FULL_DIR_INFORMATION, *PFILE_FULL_DIR_INFORMATION;
+
+typedef struct _IO_STATUS_BLOCK {
+	union {
+		NTSTATUS Status;
+		PVOID Pointer;
+	} u;
+	ULONG_PTR Information;
+} IO_STATUS_BLOCK, *PIO_STATUS_BLOCK;
+
+typedef VOID
+(NTAPI *PIO_APC_ROUTINE)(
+	IN PVOID ApcContext,
+	IN PIO_STATUS_BLOCK IoStatusBlock,
+	IN ULONG Reserved);
+
+NTSYSCALLAPI
+NTSTATUS
+NTAPI
+NtQueryDirectoryFile(
+	_In_ HANDLE FileHandle,
+	_In_opt_ HANDLE Event,
+	_In_opt_ PIO_APC_ROUTINE ApcRoutine,
+	_In_opt_ PVOID ApcContext,
+	_Out_ PIO_STATUS_BLOCK IoStatusBlock,
+	_Out_writes_bytes_(Length) PVOID FileInformation,
+	_In_ ULONG Length,
+	_In_ FILE_INFORMATION_CLASS FileInformationClass,
+	_In_ BOOLEAN ReturnSingleEntry,
+	_In_opt_ PUNICODE_STRING FileName,
+	_In_ BOOLEAN RestartScan
+);
+
+#define STATUS_NO_MORE_FILES             ((NTSTATUS)0x80000006L)
+
+#endif

From c702d4216de382a56f7f20c61e8565d732f1647d Mon Sep 17 00:00:00 2001
From: Derrick Stolee <dstolee@microsoft.com>
Date: Wed, 12 Jun 2019 00:58:49 +0000
Subject: [PATCH 178/259] unpack-trees: enable fscache for sparse-checkout

When updating the skip-worktree bits in the index to align with new
values in a sparse-checkout file, Git scans the entire working
directory with lstat() calls. In a sparse-checkout, many of these
lstat() calls are for paths that do not exist.

Enable the fscache feature during this scan. Since enable_fscache()
calls nest, the disable_fscache() method decrements a counter and
would only clear the cache if that counter reaches zero.

In a local test of a repo with ~2.2 million paths, updating the index
with git read-tree -m -u HEAD with a sparse-checkout file containing
only /.gitattributes improved from 2-3 minutes to ~6 seconds.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 unpack-trees.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/unpack-trees.c b/unpack-trees.c
index 7dc884fafd30a3..1cff7ca762374f 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -1817,7 +1817,9 @@ static void mark_new_skip_worktree(struct pattern_list *pl,
 	 * 2. Widen worktree according to sparse-checkout file.
 	 * Matched entries will have skip_wt_flag cleared (i.e. "in")
 	 */
+	enable_fscache(istate->cache_nr);
 	clear_ce_flags(istate, select_flag, skip_wt_flag, pl, show_progress);
+	disable_fscache();
 }
 
 static void populate_from_existing_patterns(struct unpack_trees_options *o,

From cbc382038774ff3ae70a2f893fa511587a1c5be0 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 11 Dec 2018 12:17:49 +0100
Subject: [PATCH 179/259] clean: make use of FSCache

The `git clean` command needs to enumerate plenty of files and
directories, and can therefore benefit from the FSCache.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 builtin/clean.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/builtin/clean.c b/builtin/clean.c
index 9b416b42a96dfe..e50e1bb39d8fe1 100644
--- a/builtin/clean.c
+++ b/builtin/clean.c
@@ -1038,6 +1038,7 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
 
 	if (repo_read_index(the_repository) < 0)
 		die(_("index file corrupt"));
+	enable_fscache(the_repository->index->cache_nr);
 
 	pl = add_pattern_list(&dir, EXC_CMDL, "--exclude option");
 	for (i = 0; i < exclude_list.nr; i++)
@@ -1112,6 +1113,7 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
 		}
 	}
 
+	disable_fscache();
 	strbuf_release(&abs_path);
 	strbuf_release(&buf);
 	string_list_clear(&del_list, 0);

From 0a7503770089be1b5d6b8013dd2797daf5862255 Mon Sep 17 00:00:00 2001
From: Sebastian Schuberth <sschuberth@gmail.com>
Date: Sun, 22 Jul 2012 23:19:24 +0200
Subject: [PATCH 180/259] gitk: Use an external icon file on Windows

Git for Windows now ships with the new Git icon from git-scm.com. Use that
icon file if it exists instead of the old procedurally drawn one.

This patch was sent upstream but so far no decision on its inclusion was
made, so commit it to our fork.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
---
 gitk-git/gitk | 49 ++++++++++++++++++++++++++-----------------------
 1 file changed, 26 insertions(+), 23 deletions(-)

diff --git a/gitk-git/gitk b/gitk-git/gitk
index a792f48e5a1a47..6b84ee13273e4a 100755
--- a/gitk-git/gitk
+++ b/gitk-git/gitk
@@ -12436,7 +12436,6 @@ if { [info exists ::env(GITK_MSGSDIR)] } {
     set gitk_prefix [file dirname [file dirname [file normalize $argv0]]]
     set gitk_libdir [file join $gitk_prefix share gitk lib]
     set gitk_msgsdir [file join $gitk_libdir msgs]
-    unset gitk_prefix
 }
 
 ## Internationalization (i18n) through msgcat and gettext. See
@@ -12799,28 +12798,32 @@ if {[expr {[exec git rev-parse --is-inside-work-tree] == "true"}]} {
 set worktree [gitworktree]
 setcoords
 makewindow
-catch {
-    image create photo gitlogo      -width 16 -height 16
-
-    image create photo gitlogominus -width  4 -height  2
-    gitlogominus put #C00000 -to 0 0 4 2
-    gitlogo copy gitlogominus -to  1 5
-    gitlogo copy gitlogominus -to  6 5
-    gitlogo copy gitlogominus -to 11 5
-    image delete gitlogominus
-
-    image create photo gitlogoplus  -width  4 -height  4
-    gitlogoplus  put #008000 -to 1 0 3 4
-    gitlogoplus  put #008000 -to 0 1 4 3
-    gitlogo copy gitlogoplus  -to  1 9
-    gitlogo copy gitlogoplus  -to  6 9
-    gitlogo copy gitlogoplus  -to 11 9
-    image delete gitlogoplus
-
-    image create photo gitlogo32    -width 32 -height 32
-    gitlogo32 copy gitlogo -zoom 2 2
-
-    wm iconphoto . -default gitlogo gitlogo32
+if {$::tcl_platform(platform) eq {windows} && [file exists $gitk_prefix/etc/git.ico]} {
+    wm iconbitmap . -default $gitk_prefix/etc/git.ico
+} else {
+    catch {
+        image create photo gitlogo      -width 16 -height 16
+
+        image create photo gitlogominus -width  4 -height  2
+        gitlogominus put #C00000 -to 0 0 4 2
+        gitlogo copy gitlogominus -to  1 5
+        gitlogo copy gitlogominus -to  6 5
+        gitlogo copy gitlogominus -to 11 5
+        image delete gitlogominus
+
+        image create photo gitlogoplus  -width  4 -height  4
+        gitlogoplus  put #008000 -to 1 0 3 4
+        gitlogoplus  put #008000 -to 0 1 4 3
+        gitlogo copy gitlogoplus  -to  1 9
+        gitlogo copy gitlogoplus  -to  6 9
+        gitlogo copy gitlogoplus  -to 11 9
+        image delete gitlogoplus
+
+        image create photo gitlogo32    -width 32 -height 32
+        gitlogo32 copy gitlogo -zoom 2 2
+
+        wm iconphoto . -default gitlogo gitlogo32
+    }
 }
 # wait for the window to become visible
 tkwait visibility .

From 95ad775382ecec2ef1c20f7f1e093b862291128a Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 16 Feb 2016 16:42:06 +0100
Subject: [PATCH 181/259] gitk: fix arrow keys in input fields with Tcl/Tk >=
 8.6

Tcl/Tk 8.6 introduced new events for the cursor left/right keys and
apparently changed the behavior of the previous event.

Let's work around that by using the new events when we are running with
Tcl/Tk 8.6 or later.

This fixes https://github.com/git-for-windows/git/issues/495

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 gitk-git/gitk | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/gitk-git/gitk b/gitk-git/gitk
index 6b84ee13273e4a..980e3e1b83f8ea 100755
--- a/gitk-git/gitk
+++ b/gitk-git/gitk
@@ -2234,7 +2234,7 @@ proc makewindow {} {
     global headctxmenu progresscanv progressitem progresscoords statusw
     global fprogitem fprogcoord lastprogupdate progupdatepending
     global rprogitem rprogcoord rownumsel numcommits
-    global have_tk85 use_ttk NS
+    global have_tk85 have_tk86 use_ttk NS
     global git_version
     global worddiff
 
@@ -2732,8 +2732,13 @@ proc makewindow {} {
     bind . <Key-Down> "selnextline 1"
     bind . <Shift-Key-Up> "dofind -1 0"
     bind . <Shift-Key-Down> "dofind 1 0"
-    bindkey <Key-Right> "goforw"
-    bindkey <Key-Left> "goback"
+    if {$have_tk86} {
+        bindkey <<NextChar>> "goforw"
+        bindkey <<PrevChar>> "goback"
+    } else {
+        bindkey <Key-Right> "goforw"
+        bindkey <Key-Left> "goback"
+    }
     bind . <Key-Prior> "selnextpage -1"
     bind . <Key-Next> "selnextpage 1"
     bind . <$M1B-Home> "allcanvs yview moveto 0.0"
@@ -12734,6 +12739,7 @@ set nullid2 "0000000000000000000000000000000000000001"
 set nullfile "/dev/null"
 
 set have_tk85 [expr {[package vcompare $tk_version "8.5"] >= 0}]
+set have_tk86 [expr {[package vcompare $tk_version "8.6"] >= 0}]
 if {![info exists have_ttk]} {
     set have_ttk [llength [info commands ::ttk::style]]
 }

From 0f608702409618ca3a2925423c711bb957d26313 Mon Sep 17 00:00:00 2001
From: "James J. Raden" <james.raden@gmail.com>
Date: Thu, 21 Jan 2016 12:07:47 -0500
Subject: [PATCH 182/259] gitk: make the "list references" default window width
 wider

When using remotes (with git-flow especially), the remote reference names
are almost always wordwrapped in the "list references" window because it's
somewhat narrow by default. It's possible to resize it with a mouse,
but it's annoying to have to do this every time, especially on Windows 10,
where the window border seems to be only one (1) pixel wide, thus making
the grabbing of the window border tricky.

Signed-off-by: James J. Raden <james.raden@gmail.com>
---
 gitk-git/gitk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gitk-git/gitk b/gitk-git/gitk
index 980e3e1b83f8ea..26294152dbf540 100755
--- a/gitk-git/gitk
+++ b/gitk-git/gitk
@@ -10201,7 +10201,7 @@ proc showrefs {} {
     text $top.list -background $bgcolor -foreground $fgcolor \
         -selectbackground $selectbgcolor -font mainfont \
         -xscrollcommand "$top.xsb set" -yscrollcommand "$top.ysb set" \
-        -width 30 -height 20 -cursor $maincursor \
+        -width 60 -height 20 -cursor $maincursor \
         -spacing1 1 -spacing3 1 -state disabled
     $top.list tag configure highlight -background $selectbgcolor
     if {![lsearch -exact $bglist $top.list]} {

From 44f756b316c14810df3ac0eacb0ff4d48cb24a66 Mon Sep 17 00:00:00 2001
From: Doug Kelly <dougk.ff7@gmail.com>
Date: Wed, 8 Jan 2014 20:28:15 -0600
Subject: [PATCH 183/259] pack-objects (mingw): demonstrate a segmentation
 fault with large deltas

There is a problem in the way 9ac3f0e5b3e4 (pack-objects: fix
performance issues on packing large deltas, 2018-07-22) initializes that
mutex in the `packing_data` struct. The problem manifests in a
segmentation fault on Windows, when a mutex (AKA critical section) is
accessed without being initialized. (With pthreads, you apparently do
not really have to initialize them?)

This was reported in https://github.com/git-for-windows/git/issues/1839.

Signed-off-by: Doug Kelly <dougk.ff7@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t7429-submodule-long-path.sh | 106 +++++++++++++++++++++++++++++++++
 1 file changed, 106 insertions(+)
 create mode 100755 t/t7429-submodule-long-path.sh

diff --git a/t/t7429-submodule-long-path.sh b/t/t7429-submodule-long-path.sh
new file mode 100755
index 00000000000000..f692cedbff7ff8
--- /dev/null
+++ b/t/t7429-submodule-long-path.sh
@@ -0,0 +1,106 @@
+#!/bin/sh
+#
+# Copyright (c) 2013 Doug Kelly
+#
+
+test_description='Test submodules with a path near PATH_MAX
+
+This test verifies that "git submodule" initialization, update and clones work, including with recursive submodules and paths approaching PATH_MAX (260 characters on Windows)
+'
+
+TEST_NO_CREATE_REPO=1
+. ./test-lib.sh
+
+longpath=""
+for (( i=0; i<4; i++ )); do
+	longpath="0123456789abcdefghijklmnopqrstuvwxyz$longpath"
+done
+# Pick a substring maximum of 90 characters
+# This should be good, since we'll add on a lot for temp directories
+longpath=${longpath:0:90}; export longpath
+
+test_expect_failure 'submodule with a long path' '
+	git config --global protocol.file.allow always &&
+	GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME= \
+	git -c init.defaultBranch=long init --bare remote &&
+	test_create_repo bundle1 &&
+	(
+		cd bundle1 &&
+		test_commit "shoot" &&
+		git rev-parse --verify HEAD >../expect
+	) &&
+	mkdir home &&
+	(
+		cd home &&
+		git clone ../remote test &&
+		cd test &&
+		git checkout -B long &&
+		git submodule add ../bundle1 $longpath &&
+		test_commit "sogood" &&
+		(
+			cd $longpath &&
+			git rev-parse --verify HEAD >actual &&
+			test_cmp ../../../expect actual
+		) &&
+		git push origin long
+	) &&
+	mkdir home2 &&
+	(
+		cd home2 &&
+		git clone ../remote test &&
+		cd test &&
+		git checkout long &&
+		git submodule update --init &&
+		(
+			cd $longpath &&
+			git rev-parse --verify HEAD >actual &&
+			test_cmp ../../../expect actual
+		)
+	)
+'
+
+test_expect_failure 'recursive submodule with a long path' '
+	GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME= \
+	git -c init.defaultBranch=long init --bare super &&
+	test_create_repo child &&
+	(
+		cd child &&
+		test_commit "shoot" &&
+		git rev-parse --verify HEAD >../expect
+	) &&
+	test_create_repo parent &&
+	(
+		cd parent &&
+		git submodule add ../child $longpath &&
+		test_commit "aim"
+	) &&
+	mkdir home3 &&
+	(
+		cd home3 &&
+		git clone ../super test &&
+		cd test &&
+		git checkout -B long &&
+		git submodule add ../parent foo &&
+		git submodule update --init --recursive &&
+		test_commit "sogood" &&
+		(
+			cd foo/$longpath &&
+			git rev-parse --verify HEAD >actual &&
+			test_cmp ../../../../expect actual
+		) &&
+		git push origin long
+	) &&
+	mkdir home4 &&
+	(
+		cd home4 &&
+		git clone ../super test --recursive &&
+		(
+			cd test/foo/$longpath &&
+			git rev-parse --verify HEAD >actual &&
+			test_cmp ../../../../expect actual
+		)
+	)
+'
+unset longpath
+
+test_done

From 781e463c2a9ea889a050b9e28299afe18d2c7ce9 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Thu, 19 Mar 2015 16:33:44 +0100
Subject: [PATCH 184/259] mingw: Support `git_terminal_prompt` with more
 terminals

The `git_terminal_prompt()` function expects the terminal window to be
attached to a Win32 Console. However, this is not the case with terminal
windows other than `cmd.exe`'s, e.g. with MSys2's own `mintty`.

Non-cmd terminals such as `mintty` still have to have a Win32 Console
to be proper console programs, but have to hide the Win32 Console to
be able to provide more flexibility (such as being resizeable not only
vertically but also horizontally). By writing to that Win32 Console,
`git_terminal_prompt()` manages only to send the prompt to nowhere and
to wait for input from a Console to which the user has no access.

This commit introduces a function specifically to support `mintty` -- or
other terminals that are compatible with MSys2's `/dev/tty` emulation. We
use the `TERM` environment variable as an indicator for that: if the value
starts with "xterm" (such as `mintty`'s "xterm_256color"), we prefer to
let `xterm_prompt()` handle the user interaction.

The most prominent user of `git_terminal_prompt()` is certainly
`git-remote-https.exe`. It is an interesting use case because both
`stdin` and `stdout` are redirected when Git calls said executable, yet
it still wants to access the terminal.

When running inside a `mintty`, the terminal is not accessible to the
`git-remote-https.exe` program, though, because it is a MinGW program
and the `mintty` terminal is not backed by a Win32 console.

To solve that problem, we simply call out to the shell -- which is an
*MSys2* program and can therefore access `/dev/tty`.

Helped-by: nalla <nalla@hamal.uberspace.de>
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/terminal.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/compat/terminal.c b/compat/terminal.c
index d54efa1c5d6ebf..2a2611855b877f 100644
--- a/compat/terminal.c
+++ b/compat/terminal.c
@@ -419,6 +419,54 @@ static int getchar_with_timeout(int timeout)
 	return getchar();
 }
 
+static char *shell_prompt(const char *prompt, int echo)
+{
+	const char *read_input[] = {
+		/* Note: call 'bash' explicitly, as 'read -s' is bash-specific */
+		"bash", "-c", echo ?
+		"cat >/dev/tty && read -r line </dev/tty && echo \"$line\"" :
+		"cat >/dev/tty && read -r -s line </dev/tty && echo \"$line\" && echo >/dev/tty",
+		NULL
+	};
+	struct child_process child = CHILD_PROCESS_INIT;
+	static struct strbuf buffer = STRBUF_INIT;
+	int prompt_len = strlen(prompt), len = -1, code;
+
+	strvec_pushv(&child.args, read_input);
+	child.in = -1;
+	child.out = -1;
+
+	if (start_command(&child))
+		return NULL;
+
+	if (write_in_full(child.in, prompt, prompt_len) != prompt_len) {
+		error("could not write to prompt script");
+		close(child.in);
+		goto ret;
+	}
+	close(child.in);
+
+	strbuf_reset(&buffer);
+	len = strbuf_read(&buffer, child.out, 1024);
+	if (len < 0) {
+		error("could not read from prompt script");
+		goto ret;
+	}
+
+	strbuf_strip_suffix(&buffer, "\n");
+	strbuf_strip_suffix(&buffer, "\r");
+
+ret:
+	close(child.out);
+	code = finish_command(&child);
+	if (code) {
+		error("failed to execute prompt script (exit code %d)", code);
+		return NULL;
+	}
+
+	return len < 0 ? NULL : buffer.buf;
+}
+
 #endif
 
 #ifndef FORCE_TEXT
@@ -430,6 +478,12 @@ char *git_terminal_prompt(const char *prompt, int echo)
 	static struct strbuf buf = STRBUF_INIT;
 	int r;
 	FILE *input_fh, *output_fh;
+#ifdef GIT_WINDOWS_NATIVE
+	const char *term = getenv("TERM");
+
+	if (term && starts_with(term, "xterm"))
+		return shell_prompt(prompt, echo);
+#endif
 
 	input_fh = fopen(INPUT_PATH, "r" FORCE_TEXT);
 	if (!input_fh)

From 021726e844fffa483d17c24db7a82406436e2e5c Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Tue, 28 Jul 2015 21:07:41 +0200
Subject: [PATCH 185/259] mingw: support long paths

Windows paths are typically limited to MAX_PATH = 260 characters, even
though the underlying NTFS file system supports paths up to 32,767 chars.
This limitation is also evident in Windows Explorer, cmd.exe and many
other applications (including IDEs).

Particularly annoying is that most Windows APIs return bogus error codes
if a relative path only barely exceeds MAX_PATH in conjunction with the
current directory, e.g. ERROR_PATH_NOT_FOUND / ENOENT instead of the
infinitely more helpful ERROR_FILENAME_EXCED_RANGE / ENAMETOOLONG.

Many Windows wide char APIs support longer than MAX_PATH paths through the
file namespace prefix ('\\?\' or '\\?\UNC\') followed by an absolute path.
Notable exceptions include functions dealing with executables and the
current directory (CreateProcess, LoadLibrary, Get/SetCurrentDirectory) as
well as the entire shell API (ShellExecute, SHGetSpecialFolderPath...).

Introduce a handle_long_path function to check the length of a specified
path properly (and fail with ENAMETOOLONG), and to optionally expand long
paths using the '\\?\' file namespace prefix. Short paths will not be
modified, so we don't need to worry about device names (NUL, CON, AUX).

Contrary to MSDN docs, the GetFullPathNameW function doesn't seem to be
limited to MAX_PATH (at least not on Win7), so we can use it to do the
heavy lifting of the conversion (translate '/' to '\', eliminate '.' and
'..', and make an absolute path).

Add long path error checking to xutftowcs_path for APIs with hard MAX_PATH
limit.

Add a new MAX_LONG_PATH constant and xutftowcs_long_path function for APIs
that support long paths.

While improved error checking is always active, long paths support must be
explicitly enabled via 'core.longpaths' option. This is to prevent end
users to shoot themselves in the foot by checking out files that Windows
Explorer, cmd/bash or their favorite IDE cannot handle.

Test suite:
Test the case is when the full pathname length of a dir is close
to 260 (MAX_PATH).
Bug report and an original reproducer by Andrey Rogozhnikov:
https://github.com/msysgit/git/pull/122#issuecomment-43604199

[jes: adjusted test number to avoid conflicts, added support for
chdir(), etc]

Thanks-to: Martin W. Kirst <maki@bitkings.de>
Thanks-to: Doug Kelly <dougk.ff7@gmail.com>
Original-test-by: Andrey Rogozhnikov <rogozhnikov.andrey@gmail.com>
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Stepan Kasal <kasal@ucw.cz>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 Documentation/config/core.txt  |   7 ++
 compat/mingw.c                 | 169 ++++++++++++++++++++++++++-------
 compat/mingw.h                 |  75 ++++++++++++++-
 compat/win32/dirent.c          |  17 ++--
 compat/win32/fscache.c         |  16 ++--
 t/t2031-checkout-long-paths.sh | 102 ++++++++++++++++++++
 t/t7429-submodule-long-path.sh |  24 +++--
 7 files changed, 346 insertions(+), 64 deletions(-)
 create mode 100755 t/t2031-checkout-long-paths.sh

diff --git a/Documentation/config/core.txt b/Documentation/config/core.txt
index b894c7e9cc8a57..55c8939452a7a4 100644
--- a/Documentation/config/core.txt
+++ b/Documentation/config/core.txt
@@ -691,6 +691,13 @@ core.fscache::
 Git for Windows uses this to bulk-read and cache lstat data of entire
 directories (instead of doing lstat file by file).
 
+core.longpaths::
+	Enable long path (> 260) support for builtin commands in Git for
+	Windows. This is disabled by default, as long paths are not supported
+	by Windows Explorer, cmd.exe and the Git for Windows tool chain
+	(msys, bash, tcl, perl...). Only enable this if you know what you're
+	doing and are prepared to live with a few quirks.
+
 core.unsetenvvars::
 	Windows-only: comma-separated list of environment variables'
 	names that need to be unset before spawning any other process.
diff --git a/compat/mingw.c b/compat/mingw.c
index c1ca68aab11a6a..6b85015f73ab6c 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -247,6 +247,27 @@ static enum hide_dotfiles_type hide_dotfiles = HIDE_DOTFILES_DOTGITONLY;
 static char *unset_environment_variables;
 int core_fscache;
 
+int are_long_paths_enabled(void)
+{
+	/* default to `false` during initialization */
+	static const int fallback = 0;
+
+	static int enabled = -1;
+
+	if (enabled < 0) {
+		/* avoid infinite recursion */
+		if (!the_repository)
+			return fallback;
+
+		if (the_repository->config &&
+		    the_repository->config->hash_initialized &&
+		    git_config_get_bool("core.longpaths", &enabled) < 0)
+			enabled = 0;
+	}
+
+	return enabled < 0 ? fallback : enabled;
+}
+
 int mingw_core_config(const char *var, const char *value,
 		      const struct config_context *ctx, void *cb)
 {
@@ -311,8 +332,8 @@ static wchar_t *normalize_ntpath(wchar_t *wbuf)
 int mingw_unlink(const char *pathname)
 {
 	int ret, tries = 0;
-	wchar_t wpathname[MAX_PATH];
-	if (xutftowcs_path(wpathname, pathname) < 0)
+	wchar_t wpathname[MAX_LONG_PATH];
+	if (xutftowcs_long_path(wpathname, pathname) < 0)
 		return -1;
 
 	if (DeleteFileW(wpathname))
@@ -344,7 +365,7 @@ static int is_dir_empty(const wchar_t *wpath)
 {
 	WIN32_FIND_DATAW findbuf;
 	HANDLE handle;
-	wchar_t wbuf[MAX_PATH + 2];
+	wchar_t wbuf[MAX_LONG_PATH + 2];
 	wcscpy(wbuf, wpath);
 	wcscat(wbuf, L"\\*");
 	handle = FindFirstFileW(wbuf, &findbuf);
@@ -365,7 +386,7 @@ static int is_dir_empty(const wchar_t *wpath)
 int mingw_rmdir(const char *pathname)
 {
 	int ret, tries = 0;
-	wchar_t wpathname[MAX_PATH];
+	wchar_t wpathname[MAX_LONG_PATH];
 	struct stat st;
 
 	/*
@@ -387,7 +408,7 @@ int mingw_rmdir(const char *pathname)
 		return -1;
 	}
 
-	if (xutftowcs_path(wpathname, pathname) < 0)
+	if (xutftowcs_long_path(wpathname, pathname) < 0)
 		return -1;
 
 	while ((ret = _wrmdir(wpathname)) == -1 && tries < ARRAY_SIZE(delay)) {
@@ -466,15 +487,18 @@ static int set_hidden_flag(const wchar_t *path, int set)
 int mingw_mkdir(const char *path, int mode)
 {
 	int ret;
-	wchar_t wpath[MAX_PATH];
+	wchar_t wpath[MAX_LONG_PATH];
 
 	if (!is_valid_win32_path(path, 0)) {
 		errno = EINVAL;
 		return -1;
 	}
 
-	if (xutftowcs_path(wpath, path) < 0)
+	/* CreateDirectoryW path limit is 248 (MAX_PATH - 8.3 file name) */
+	if (xutftowcs_path_ex(wpath, path, MAX_LONG_PATH, -1, 248,
+			      are_long_paths_enabled()) < 0)
 		return -1;
+
 	ret = _wmkdir(wpath);
 	if (!ret && needs_hiding(path))
 		return set_hidden_flag(wpath, 1);
@@ -561,7 +585,7 @@ int mingw_open (const char *filename, int oflags, ...)
 	va_list args;
 	unsigned mode;
 	int fd, create = (oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL);
-	wchar_t wfilename[MAX_PATH];
+	wchar_t wfilename[MAX_LONG_PATH];
 	open_fn_t open_fn;
 
 	va_start(args, oflags);
@@ -589,7 +613,7 @@ int mingw_open (const char *filename, int oflags, ...)
 
 	if (filename && !strcmp(filename, "/dev/null"))
 		wcscpy(wfilename, L"nul");
-	else if (xutftowcs_path(wfilename, filename) < 0)
+	else if (xutftowcs_long_path(wfilename, filename) < 0)
 		return -1;
 
 	fd = open_fn(wfilename, oflags, mode);
@@ -647,14 +671,14 @@ FILE *mingw_fopen (const char *filename, const char *otype)
 {
 	int hide = needs_hiding(filename);
 	FILE *file;
-	wchar_t wfilename[MAX_PATH], wotype[4];
+	wchar_t wfilename[MAX_LONG_PATH], wotype[4];
 	if (filename && !strcmp(filename, "/dev/null"))
 		wcscpy(wfilename, L"nul");
 	else if (!is_valid_win32_path(filename, 1)) {
 		int create = otype && strchr(otype, 'w');
 		errno = create ? EINVAL : ENOENT;
 		return NULL;
-	} else if (xutftowcs_path(wfilename, filename) < 0)
+	} else if (xutftowcs_long_path(wfilename, filename) < 0)
 		return NULL;
 
 	if (xutftowcs(wotype, otype, ARRAY_SIZE(wotype)) < 0)
@@ -676,14 +700,14 @@ FILE *mingw_freopen (const char *filename, const char *otype, FILE *stream)
 {
 	int hide = needs_hiding(filename);
 	FILE *file;
-	wchar_t wfilename[MAX_PATH], wotype[4];
+	wchar_t wfilename[MAX_LONG_PATH], wotype[4];
 	if (filename && !strcmp(filename, "/dev/null"))
 		wcscpy(wfilename, L"nul");
 	else if (!is_valid_win32_path(filename, 1)) {
 		int create = otype && strchr(otype, 'w');
 		errno = create ? EINVAL : ENOENT;
 		return NULL;
-	} else if (xutftowcs_path(wfilename, filename) < 0)
+	} else if (xutftowcs_long_path(wfilename, filename) < 0)
 		return NULL;
 
 	if (xutftowcs(wotype, otype, ARRAY_SIZE(wotype)) < 0)
@@ -733,7 +757,7 @@ ssize_t mingw_write(int fd, const void *buf, size_t len)
 		HANDLE h = (HANDLE) _get_osfhandle(fd);
 		if (GetFileType(h) != FILE_TYPE_PIPE) {
 			if (orig == EINVAL) {
-				wchar_t path[MAX_PATH];
+				wchar_t path[MAX_LONG_PATH];
 				DWORD ret = GetFinalPathNameByHandleW(h, path,
 								ARRAY_SIZE(path), 0);
 				UINT drive_type = ret > 0 && ret < ARRAY_SIZE(path) ?
@@ -770,27 +794,33 @@ ssize_t mingw_write(int fd, const void *buf, size_t len)
 
 int mingw_access(const char *filename, int mode)
 {
-	wchar_t wfilename[MAX_PATH];
+	wchar_t wfilename[MAX_LONG_PATH];
 	if (!strcmp("nul", filename) || !strcmp("/dev/null", filename))
 		return 0;
-	if (xutftowcs_path(wfilename, filename) < 0)
+	if (xutftowcs_long_path(wfilename, filename) < 0)
 		return -1;
 	/* X_OK is not supported by the MSVCRT version */
 	return _waccess(wfilename, mode & ~X_OK);
 }
 
+/* cached length of current directory for handle_long_path */
+static int current_directory_len = 0;
+
 int mingw_chdir(const char *dirname)
 {
-	wchar_t wdirname[MAX_PATH];
-	if (xutftowcs_path(wdirname, dirname) < 0)
+	int result;
+	wchar_t wdirname[MAX_LONG_PATH];
+	if (xutftowcs_long_path(wdirname, dirname) < 0)
 		return -1;
-	return _wchdir(wdirname);
+	result = _wchdir(wdirname);
+	current_directory_len = GetCurrentDirectoryW(0, NULL);
+	return result;
 }
 
 int mingw_chmod(const char *filename, int mode)
 {
-	wchar_t wfilename[MAX_PATH];
-	if (xutftowcs_path(wfilename, filename) < 0)
+	wchar_t wfilename[MAX_LONG_PATH];
+	if (xutftowcs_long_path(wfilename, filename) < 0)
 		return -1;
 	return _wchmod(wfilename, mode);
 }
@@ -838,8 +868,8 @@ static int has_valid_directory_prefix(wchar_t *wfilename)
 static int do_lstat(int follow, const char *file_name, struct stat *buf)
 {
 	WIN32_FILE_ATTRIBUTE_DATA fdata;
-	wchar_t wfilename[MAX_PATH];
-	if (xutftowcs_path(wfilename, file_name) < 0)
+	wchar_t wfilename[MAX_LONG_PATH];
+	if (xutftowcs_long_path(wfilename, file_name) < 0)
 		return -1;
 
 	if (GetFileAttributesExW(wfilename, GetFileExInfoStandard, &fdata)) {
@@ -1010,10 +1040,10 @@ int mingw_utime (const char *file_name, const struct utimbuf *times)
 	FILETIME mft, aft;
 	int rc;
 	DWORD attrs;
-	wchar_t wfilename[MAX_PATH];
+	wchar_t wfilename[MAX_LONG_PATH];
 	HANDLE osfilehandle;
 
-	if (xutftowcs_path(wfilename, file_name) < 0)
+	if (xutftowcs_long_path(wfilename, file_name) < 0)
 		return -1;
 
 	/* must have write permission */
@@ -1096,6 +1126,7 @@ char *mingw_mktemp(char *template)
 	wchar_t wtemplate[MAX_PATH];
 	int offset = 0;
 
+	/* we need to return the path, thus no long paths here! */
 	if (xutftowcs_path(wtemplate, template) < 0)
 		return NULL;
 
@@ -1747,6 +1778,10 @@ static pid_t mingw_spawnve_fd(const char *cmd, const char **argv, char **deltaen
 
 	if (*argv && !strcmp(cmd, *argv))
 		wcmd[0] = L'\0';
+	/*
+	 * Paths to executables and to the current directory do not support
+	 * long paths, therefore we cannot use xutftowcs_long_path() here.
+	 */
 	else if (xutftowcs_path(wcmd, cmd) < 0)
 		return -1;
 	if (dir && xutftowcs_path(wdir, dir) < 0)
@@ -2395,8 +2430,9 @@ int mingw_rename(const char *pold, const char *pnew)
 {
 	DWORD attrs, gle;
 	int tries = 0;
-	wchar_t wpold[MAX_PATH], wpnew[MAX_PATH];
-	if (xutftowcs_path(wpold, pold) < 0 || xutftowcs_path(wpnew, pnew) < 0)
+	wchar_t wpold[MAX_LONG_PATH], wpnew[MAX_LONG_PATH];
+	if (xutftowcs_long_path(wpold, pold) < 0 ||
+	    xutftowcs_long_path(wpnew, pnew) < 0)
 		return -1;
 
 	/*
@@ -2714,9 +2750,9 @@ int mingw_raise(int sig)
 
 int link(const char *oldpath, const char *newpath)
 {
-	wchar_t woldpath[MAX_PATH], wnewpath[MAX_PATH];
-	if (xutftowcs_path(woldpath, oldpath) < 0 ||
-		xutftowcs_path(wnewpath, newpath) < 0)
+	wchar_t woldpath[MAX_LONG_PATH], wnewpath[MAX_LONG_PATH];
+	if (xutftowcs_long_path(woldpath, oldpath) < 0 ||
+	    xutftowcs_long_path(wnewpath, newpath) < 0)
 		return -1;
 
 	if (!CreateHardLinkW(wnewpath, woldpath, NULL)) {
@@ -2784,8 +2820,8 @@ int mingw_is_mount_point(struct strbuf *path)
 {
 	WIN32_FIND_DATAW findbuf = { 0 };
 	HANDLE handle;
-	wchar_t wfilename[MAX_PATH];
-	int wlen = xutftowcs_path(wfilename, path->buf);
+	wchar_t wfilename[MAX_LONG_PATH];
+	int wlen = xutftowcs_long_path(wfilename, path->buf);
 	if (wlen < 0)
 		die(_("could not get long path for '%s'"), path->buf);
 
@@ -2930,9 +2966,9 @@ static size_t append_system_bin_dirs(char *path, size_t size)
 
 static int is_system32_path(const char *path)
 {
-	WCHAR system32[MAX_PATH], wpath[MAX_PATH];
+	WCHAR system32[MAX_LONG_PATH], wpath[MAX_LONG_PATH];
 
-	if (xutftowcs_path(wpath, path) < 0 ||
+	if (xutftowcs_long_path(wpath, path) < 0 ||
 	    !GetSystemDirectoryW(system32, ARRAY_SIZE(system32)) ||
 	    _wcsicmp(system32, wpath))
 		return 0;
@@ -3344,6 +3380,68 @@ int is_valid_win32_path(const char *path, int allow_literal_nul)
 	}
 }
 
+int handle_long_path(wchar_t *path, int len, int max_path, int expand)
+{
+	int result;
+	wchar_t buf[MAX_LONG_PATH];
+
+	/*
+	 * we don't need special handling if path is relative to the current
+	 * directory, and current directory + path don't exceed the desired
+	 * max_path limit. This should cover > 99 % of cases with minimal
+	 * performance impact (git almost always uses relative paths).
+	 */
+	if ((len < 2 || (!is_dir_sep(path[0]) && path[1] != ':')) &&
+	    (current_directory_len + len < max_path))
+		return len;
+
+	/*
+	 * handle everything else:
+	 * - absolute paths: "C:\dir\file"
+	 * - absolute UNC paths: "\\server\share\dir\file"
+	 * - absolute paths on current drive: "\dir\file"
+	 * - relative paths on other drive: "X:file"
+	 * - prefixed paths: "\\?\...", "\\.\..."
+	 */
+
+	/* convert to absolute path using GetFullPathNameW */
+	result = GetFullPathNameW(path, MAX_LONG_PATH, buf, NULL);
+	if (!result) {
+		errno = err_win_to_posix(GetLastError());
+		return -1;
+	}
+
+	/*
+	 * return absolute path if it fits within max_path (even if
+	 * "cwd + path" doesn't due to '..' components)
+	 */
+	if (result < max_path) {
+		wcscpy(path, buf);
+		return result;
+	}
+
+	/* error out if we shouldn't expand the path or buf is too small */
+	if (!expand || result >= MAX_LONG_PATH - 6) {
+		errno = ENAMETOOLONG;
+		return -1;
+	}
+
+	/* prefix full path with "\\?\" or "\\?\UNC\" */
+	if (buf[0] == '\\') {
+		/* ...unless already prefixed */
+		if (buf[1] == '\\' && (buf[2] == '?' || buf[2] == '.'))
+			return len;
+
+		wcscpy(path, L"\\\\?\\UNC\\");
+		wcscpy(path + 8, buf + 2);
+		return result + 6;
+	} else {
+		wcscpy(path, L"\\\\?\\");
+		wcscpy(path + 4, buf);
+		return result + 4;
+	}
+}
+
 #if !defined(_MSC_VER)
 /*
  * Disable MSVCRT command line wildcard expansion (__getmainargs called from
@@ -3505,6 +3603,9 @@ int wmain(int argc, const wchar_t **wargv)
 	/* initialize Unicode console */
 	winansi_init();
 
+	/* init length of current directory for handle_long_path */
+	current_directory_len = GetCurrentDirectoryW(0, NULL);
+
 	/* invoke the real main() using our utf8 version of argv. */
 	exit_status = main(argc, argv);
 
diff --git a/compat/mingw.h b/compat/mingw.h
index 97cdb8d51631ea..bc1d36b49d5a17 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -12,6 +12,7 @@ typedef _sigset_t sigset_t;
 #endif
 
 extern int core_fscache;
+int are_long_paths_enabled(void);
 
 struct config_context;
 int mingw_core_config(const char *var, const char *value,
@@ -520,6 +521,42 @@ int is_path_owned_by_current_sid(const char *path, struct strbuf *report);
 int is_valid_win32_path(const char *path, int allow_literal_nul);
 #define is_valid_path(path) is_valid_win32_path(path, 0)
 
+/**
+ * Max length of long paths (exceeding MAX_PATH). The actual maximum supported
+ * by NTFS is 32,767 (* sizeof(wchar_t)), but we choose an arbitrary smaller
+ * value to limit required stack memory.
+ */
+#define MAX_LONG_PATH 4096
+
+/**
+ * Handles paths that would exceed the MAX_PATH limit of Windows Unicode APIs.
+ *
+ * With expand == false, the function checks for over-long paths and fails
+ * with ENAMETOOLONG. The path parameter is not modified, except if cwd + path
+ * exceeds max_path, but the resulting absolute path doesn't (e.g. due to
+ * eliminating '..' components). The path parameter must point to a buffer
+ * of max_path wide characters.
+ *
+ * With expand == true, an over-long path is automatically converted in place
+ * to an absolute path prefixed with '\\?\', and the new length is returned.
+ * The path parameter must point to a buffer of MAX_LONG_PATH wide characters.
+ *
+ * Parameters:
+ * path: path to check and / or convert
+ * len: size of path on input (number of wide chars without \0)
+ * max_path: max short path length to check (usually MAX_PATH = 260, but just
+ * 248 for CreateDirectoryW)
+ * expand: false to only check the length, true to expand the path to a
+ * '\\?\'-prefixed absolute path
+ *
+ * Return:
+ * length of the resulting path, or -1 on failure
+ *
+ * Errors:
+ * ENAMETOOLONG if path is too long
+ */
+int handle_long_path(wchar_t *path, int len, int max_path, int expand);
+
 /**
  * Converts UTF-8 encoded string to UTF-16LE.
  *
@@ -578,18 +615,46 @@ static inline int xutftowcs(wchar_t *wcs, const char *utf, size_t wcslen)
 }
 
 /**
- * Simplified file system specific variant of xutftowcsn, assumes output
- * buffer size is MAX_PATH wide chars and input string is \0-terminated,
- * fails with ENAMETOOLONG if input string is too long.
+ * Simplified file system specific wrapper of xutftowcsn and handle_long_path.
+ * Converts ERANGE to ENAMETOOLONG. If expand is true, wcs must be at least
+ * MAX_LONG_PATH wide chars (see handle_long_path).
  */
-static inline int xutftowcs_path(wchar_t *wcs, const char *utf)
+static inline int xutftowcs_path_ex(wchar_t *wcs, const char *utf,
+		size_t wcslen, int utflen, int max_path, int expand)
 {
-	int result = xutftowcsn(wcs, utf, MAX_PATH, -1);
+	int result = xutftowcsn(wcs, utf, wcslen, utflen);
 	if (result < 0 && errno == ERANGE)
 		errno = ENAMETOOLONG;
+	if (result >= 0)
+		result = handle_long_path(wcs, result, max_path, expand);
 	return result;
 }
 
+/**
+ * Simplified file system specific variant of xutftowcsn, assumes output
+ * buffer size is MAX_PATH wide chars and input string is \0-terminated,
+ * fails with ENAMETOOLONG if input string is too long. Typically used for
+ * Windows APIs that don't support long paths, e.g. SetCurrentDirectory,
+ * LoadLibrary, CreateProcess...
+ */
+static inline int xutftowcs_path(wchar_t *wcs, const char *utf)
+{
+	return xutftowcs_path_ex(wcs, utf, MAX_PATH, -1, MAX_PATH, 0);
+}
+
+/**
+ * Simplified file system specific variant of xutftowcsn for Windows APIs
+ * that support long paths via '\\?\'-prefix, assumes output buffer size is
+ * MAX_LONG_PATH wide chars, fails with ENAMETOOLONG if input string is too
+ * long. The 'core.longpaths' git-config option controls whether the path
+ * is only checked or expanded to a long path.
+ */
+static inline int xutftowcs_long_path(wchar_t *wcs, const char *utf)
+{
+	return xutftowcs_path_ex(wcs, utf, MAX_LONG_PATH, -1, MAX_PATH,
+				 are_long_paths_enabled());
+}
+
 /**
  * Converts UTF-16LE encoded string to UTF-8.
  *
diff --git a/compat/win32/dirent.c b/compat/win32/dirent.c
index 139d2ba3c4da34..c9fe2454efc01c 100644
--- a/compat/win32/dirent.c
+++ b/compat/win32/dirent.c
@@ -65,19 +65,24 @@ static int dirent_closedir(dirent_DIR *dir)
 
 DIR *dirent_opendir(const char *name)
 {
-	wchar_t pattern[MAX_PATH + 2]; /* + 2 for '/' '*' */
+	wchar_t pattern[MAX_LONG_PATH + 2]; /* + 2 for "\*" */
 	WIN32_FIND_DATAW fdata;
 	HANDLE h;
 	int len;
 	dirent_DIR *dir;
 
-	/* convert name to UTF-16 and check length < MAX_PATH */
-	if ((len = xutftowcs_path(pattern, name)) < 0)
+	/* convert name to UTF-16 and check length */
+	if ((len = xutftowcs_path_ex(pattern, name, MAX_LONG_PATH, -1,
+				     MAX_PATH - 2,
+				     are_long_paths_enabled())) < 0)
 		return NULL;
 
-	/* append optional '/' and wildcard '*' */
+	/*
+	 * append optional '\' and wildcard '*'. Note: we need to use '\' as
+	 * Windows doesn't translate '/' to '\' for "\\?\"-prefixed paths.
+	 */
 	if (len && !is_dir_sep(pattern[len - 1]))
-		pattern[len++] = '/';
+		pattern[len++] = '\\';
 	pattern[len++] = '*';
 	pattern[len] = 0;
 
@@ -90,7 +95,7 @@ DIR *dirent_opendir(const char *name)
 	}
 
 	/* initialize DIR structure and copy first dir entry */
-	dir = xmalloc(sizeof(dirent_DIR) + MAX_PATH);
+	dir = xmalloc(sizeof(dirent_DIR) + MAX_LONG_PATH);
 	dir->base_dir.preaddir = (struct dirent *(*)(DIR *dir)) dirent_readdir;
 	dir->base_dir.pclosedir = (int (*)(DIR *dir)) dirent_closedir;
 	dir->dd_handle = h;
diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index da19ba0994de58..581808a64b6cd6 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -80,7 +80,7 @@ struct fsentry {
 struct heap_fsentry {
 	union {
 		struct fsentry ent;
-		char dummy[sizeof(struct fsentry) + MAX_PATH];
+		char dummy[sizeof(struct fsentry) + MAX_LONG_PATH];
 	} u;
 };
 
@@ -123,7 +123,7 @@ static void fsentry_init(struct fsentry *fse, struct fsentry *list,
 			 const char *name, size_t len)
 {
 	fse->list = list;
-	if (len > MAX_PATH)
+	if (len > MAX_LONG_PATH)
 		BUG("Trying to allocate fsentry for long path '%.*s'",
 		    (int)len, name);
 	memcpy(fse->dirent.d_name, name, len);
@@ -224,7 +224,7 @@ static struct fsentry *fseentry_create_entry(struct fscache *cache,
 static struct fsentry *fsentry_create_list(struct fscache *cache, const struct fsentry *dir,
 					   int *dir_not_found)
 {
-	wchar_t pattern[MAX_PATH];
+	wchar_t pattern[MAX_LONG_PATH];
 	NTSTATUS status;
 	IO_STATUS_BLOCK iosb;
 	PFILE_FULL_DIR_INFORMATION di;
@@ -235,13 +235,11 @@ static struct fsentry *fsentry_create_list(struct fscache *cache, const struct f
 
 	*dir_not_found = 0;
 
-	/* convert name to UTF-16 and check length < MAX_PATH */
-	if ((wlen = xutftowcsn(pattern, dir->dirent.d_name, MAX_PATH,
-			       dir->len)) < 0) {
-		if (errno == ERANGE)
-			errno = ENAMETOOLONG;
+	/* convert name to UTF-16 and check length */
+	if ((wlen = xutftowcs_path_ex(pattern, dir->dirent.d_name,
+				      MAX_LONG_PATH, dir->len, MAX_PATH - 2,
+				      are_long_paths_enabled())) < 0)
 		return NULL;
-	}
 
 	/* handle CWD */
 	if (!wlen) {
diff --git a/t/t2031-checkout-long-paths.sh b/t/t2031-checkout-long-paths.sh
new file mode 100755
index 00000000000000..f30f8920ca689c
--- /dev/null
+++ b/t/t2031-checkout-long-paths.sh
@@ -0,0 +1,102 @@
+#!/bin/sh
+
+test_description='checkout long paths on Windows
+
+Ensures that Git for Windows can deal with long paths (>260) enabled via core.longpaths'
+
+. ./test-lib.sh
+
+if test_have_prereq !MINGW
+then
+	skip_all='skipping MINGW specific long paths test'
+	test_done
+fi
+
+test_expect_success setup '
+	p=longpathxx && # -> 10
+	p=$p$p$p$p$p && # -> 50
+	p=$p$p$p$p$p && # -> 250
+
+	path=${p}/longtestfile && # -> 263 (MAX_PATH = 260)
+
+	blob=$(echo foobar | git hash-object -w --stdin) &&
+
+	printf "100644 %s 0\t%s\n" "$blob" "$path" |
+	git update-index --add --index-info &&
+	git commit -m initial -q
+'
+
+test_expect_success 'checkout of long paths without core.longpaths fails' '
+	git config core.longpaths false &&
+	test_must_fail git checkout -f 2>error &&
+	grep -q "Filename too long" error &&
+	test ! -d longpa*
+'
+
+test_expect_success 'checkout of long paths with core.longpaths works' '
+	git config core.longpaths true &&
+	git checkout -f &&
+	test_path_is_file longpa*/longtestfile
+'
+
+test_expect_success 'update of long paths' '
+	echo frotz >>$(ls longpa*/longtestfile) &&
+	echo $path > expect &&
+	git ls-files -m > actual &&
+	test_cmp expect actual &&
+	git add $path &&
+	git commit -m second &&
+	git grep "frotz" HEAD -- $path
+'
+
+test_expect_success cleanup '
+	# bash cannot delete the trash dir if it contains a long path
+	# lets help cleaning up (unless in debug mode)
+	if test -z "$debug"
+	then
+		rm -rf longpa~1
+	fi
+'
+
+# check that the template used in the test won't be too long:
+abspath="$(pwd)"/testdir
+test ${#abspath} -gt 230 ||
+test_set_prereq SHORTABSPATH
+
+test_expect_success SHORTABSPATH 'clean up path close to MAX_PATH' '
+	p=/123456789abcdef/123456789abcdef/123456789abcdef/123456789abc/ef &&
+	p=y$p$p$p$p &&
+	subdir="x$(echo "$p" | tail -c $((253 - ${#abspath})) - )" &&
+	# Now, $abspath/$subdir has exactly 254 characters, and is inside CWD
+	p2="$abspath/$subdir" &&
+	test 254 = ${#p2} &&
+
+	# Be careful to overcome path limitations of the MSys tools and split
+	# the $subdir into two parts. ($subdir2 has to contain 16 chars and a
+	# slash somewhere following; that is why we asked for abspath <= 230 and
+	# why we placed a slash near the end of the $subdir template.)
+	subdir2=${subdir#????????????????*/} &&
+	subdir1=testdir/${subdir%/$subdir2} &&
+	mkdir -p "$subdir1" &&
+	i=0 &&
+	# The most important case is when absolute path is 258 characters long,
+	# and that will be when i == 4.
+	while test $i -le 7
+	do
+		mkdir -p $subdir2 &&
+		touch $subdir2/one-file &&
+		mv ${subdir2%%/*} "$subdir1/" &&
+		subdir2=z${subdir2} &&
+		i=$(($i+1)) ||
+		exit 1
+	done &&
+
+	# now check that git is able to clear the tree:
+	(cd testdir &&
+	 git init &&
+	 git config core.longpaths yes &&
+	 git clean -fdx) &&
+	test ! -d "$subdir1"
+'
+
+test_done
diff --git a/t/t7429-submodule-long-path.sh b/t/t7429-submodule-long-path.sh
index f692cedbff7ff8..458519eafd6f03 100755
--- a/t/t7429-submodule-long-path.sh
+++ b/t/t7429-submodule-long-path.sh
@@ -11,15 +11,20 @@ This test verifies that "git submodule" initialization, update and clones work,
 TEST_NO_CREATE_REPO=1
 . ./test-lib.sh
 
-longpath=""
-for (( i=0; i<4; i++ )); do
-	longpath="0123456789abcdefghijklmnopqrstuvwxyz$longpath"
-done
-# Pick a substring maximum of 90 characters
-# This should be good, since we'll add on a lot for temp directories
-longpath=${longpath:0:90}; export longpath
+# cloning a submodule calls is_git_directory("$path/../.git/modules/$path"),
+# which effectively limits the maximum length to PATH_MAX / 2 minus some
+# overhead; start with 3 * 36 = 108 chars (test 2 fails if >= 110)
+longpath36=0123456789abcdefghijklmnopqrstuvwxyz
+longpath180=$longpath36$longpath36$longpath36$longpath36$longpath36
 
-test_expect_failure 'submodule with a long path' '
+# the git database must fit within PATH_MAX, which limits the submodule name
+# to PATH_MAX - len(pwd) - ~90 (= len("/objects//") + 40-byte sha1 + some
+# overhead from the test case)
+pwd=$(pwd)
+pwdlen=$(echo "$pwd" | wc -c)
+longpath=$(echo $longpath180 | cut -c 1-$((170-$pwdlen)))
+
+test_expect_success 'submodule with a long path' '
 	git config --global protocol.file.allow always &&
 	GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME= \
 	git -c init.defaultBranch=long init --bare remote &&
@@ -59,7 +64,7 @@ test_expect_failure 'submodule with a long path' '
 	)
 '
 
-test_expect_failure 'recursive submodule with a long path' '
+test_expect_success 'recursive submodule with a long path' '
 	GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME= \
 	git -c init.defaultBranch=long init --bare super &&
 	test_create_repo child &&
@@ -101,6 +106,5 @@ test_expect_failure 'recursive submodule with a long path' '
 		)
 	)
 '
-unset longpath
 
 test_done

From fc0ca2bc924c9506a28ce2a243bf9228f28918d9 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sat, 9 May 2015 02:11:48 +0200
Subject: [PATCH 186/259] compat/terminal.c: only use the Windows console if
 bash 'read -r' fails
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Accessing the Windows console through the special CONIN$ / CONOUT$ devices
doesn't work properly for non-ASCII usernames an passwords.

It also doesn't work for terminal emulators that hide the native console
window (such as mintty), and 'TERM=xterm*' is not necessarily a reliable
indicator for such terminals.

The new shell_prompt() function, on the other hand, works fine for both
MSys1 and MSys2, in native console windows as well as mintty, and properly
supports Unicode. It just needs bash on the path (for 'read -s', which is
bash-specific).

On Windows, try to use the shell to read from the terminal. If that fails
with ENOENT (i.e. bash was not found), use CONIN/OUT as fallback.

Note: To test this, create a UTF-8 credential file with non-ASCII chars,
e.g. in git-bash: 'echo url=http://täst.com > cred.txt'. Then in git-cmd,
'git credential fill <cred.txt' works (shell version), while calling git
without the git-wrapper (i.e. 'mingw64\bin\git credential fill <cred.txt')
mangles non-ASCII chars in both console output and input.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/terminal.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/compat/terminal.c b/compat/terminal.c
index 2a2611855b877f..e8994aaf0ed9bc 100644
--- a/compat/terminal.c
+++ b/compat/terminal.c
@@ -435,6 +435,7 @@ static char *shell_prompt(const char *prompt, int echo)
 	strvec_pushv(&child.args, read_input);
 	child.in = -1;
 	child.out = -1;
+	child.silent_exec_failure = 1;
 
 	if (start_command(&child))
 		return NULL;
@@ -478,11 +479,14 @@ char *git_terminal_prompt(const char *prompt, int echo)
 	static struct strbuf buf = STRBUF_INIT;
 	int r;
 	FILE *input_fh, *output_fh;
+
 #ifdef GIT_WINDOWS_NATIVE
-	const char *term = getenv("TERM");
 
-	if (term && starts_with(term, "xterm"))
-		return shell_prompt(prompt, echo);
+	/* try shell_prompt first, fall back to CONIN/OUT if bash is missing */
+	char *result = shell_prompt(prompt, echo);
+	if (result || errno != ENOENT)
+		return result;
+
 #endif
 
 	input_fh = fopen(INPUT_PATH, "r" FORCE_TEXT);

From f4942ce48afd8942023d3f097daa850f1c1a8999 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sat, 5 Jul 2014 00:00:36 +0200
Subject: [PATCH 187/259] Win32: fix 'lstat("dir/")' with long paths

Use a suffciently large buffer to strip the trailing slash.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/mingw.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 6b85015f73ab6c..d4af216d7b5064 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -940,7 +940,7 @@ static int do_lstat(int follow, const char *file_name, struct stat *buf)
 static int do_stat_internal(int follow, const char *file_name, struct stat *buf)
 {
 	int namelen;
-	char alt_name[PATH_MAX];
+	char alt_name[MAX_LONG_PATH];
 
 	if (!do_lstat(follow, file_name, buf))
 		return 0;
@@ -956,7 +956,7 @@ static int do_stat_internal(int follow, const char *file_name, struct stat *buf)
 		return -1;
 	while (namelen && file_name[namelen-1] == '/')
 		--namelen;
-	if (!namelen || namelen >= PATH_MAX)
+	if (!namelen || namelen >= MAX_LONG_PATH)
 		return -1;
 
 	memcpy(alt_name, file_name, namelen);

From 7a21b9defdefabe59b8cd08263e90b312ab7a986 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 23 Feb 2018 02:50:03 +0100
Subject: [PATCH 188/259] mingw (git_terminal_prompt): do fall back to
 CONIN$/CONOUT$ method

To support Git Bash running in a MinTTY, we use a dirty trick to access
the MSYS2 pseudo terminal: we execute a Bash snippet that accesses
/dev/tty.

The idea was to fall back to writing to/reading from CONOUT$/CONIN$ if
that Bash call failed because Bash was not found.

However, we should fall back even in other error conditions, because we
have not successfully read the user input. Let's make it so.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/terminal.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compat/terminal.c b/compat/terminal.c
index e8994aaf0ed9bc..66bf4b55d0b49f 100644
--- a/compat/terminal.c
+++ b/compat/terminal.c
@@ -484,7 +484,7 @@ char *git_terminal_prompt(const char *prompt, int echo)
 
 	/* try shell_prompt first, fall back to CONIN/OUT if bash is missing */
 	char *result = shell_prompt(prompt, echo);
-	if (result || errno != ENOENT)
+	if (result)
 		return result;
 
 #endif

From b6b464a06c3c296e2fff1b788ddcda25daf51783 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 6 Sep 2023 09:14:47 +0200
Subject: [PATCH 189/259] win32(long path support): leave drive-less absolute
 paths intact

When trying to ensure that long paths are handled correctly, we
first normalize absolute paths as we encounter them.

However, if the path is a so-called "drive-less" absolute path, i.e. if
it is relative to the current drive but _does_ start with a directory
separator, we would want the normalized path to be such a drive-less
absolute path, too.

Let's do that, being careful to still include the drive prefix when we
need to go through the `\\?\` dance (because there, the drive prefix is
absolutely required).

This fixes https://github.com/git-for-windows/git/issues/4586.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c                 | 12 +++++++++++-
 t/t2031-checkout-long-paths.sh |  9 +++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index d4af216d7b5064..92c8140841d6f2 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -304,6 +304,11 @@ int mingw_core_config(const char *var, const char *value,
 	return 0;
 }
 
+static inline int is_wdir_sep(wchar_t wchar)
+{
+	return wchar == L'/' || wchar == L'\\';
+}
+
 /* Normalizes NT paths as returned by some low-level APIs. */
 static wchar_t *normalize_ntpath(wchar_t *wbuf)
 {
@@ -3416,7 +3421,12 @@ int handle_long_path(wchar_t *path, int len, int max_path, int expand)
 	 * "cwd + path" doesn't due to '..' components)
 	 */
 	if (result < max_path) {
-		wcscpy(path, buf);
+		/* Be careful not to add a drive prefix if there was none */
+		if (is_wdir_sep(path[0]) &&
+		    !is_wdir_sep(buf[0]) && buf[1] == L':' && is_wdir_sep(buf[2]))
+			wcscpy(path, buf + 2);
+		else
+			wcscpy(path, buf);
 		return result;
 	}
 
diff --git a/t/t2031-checkout-long-paths.sh b/t/t2031-checkout-long-paths.sh
index f30f8920ca689c..15416a1d6ee8c7 100755
--- a/t/t2031-checkout-long-paths.sh
+++ b/t/t2031-checkout-long-paths.sh
@@ -99,4 +99,13 @@ test_expect_success SHORTABSPATH 'clean up path close to MAX_PATH' '
 	test ! -d "$subdir1"
 '
 
+test_expect_success SYMLINKS_WINDOWS 'leave drive-less, short paths intact' '
+	printf "/Program Files" >symlink-target &&
+	symlink_target_oid="$(git hash-object -w --stdin <symlink-target)" &&
+	git update-index --add --cacheinfo 120000,$symlink_target_oid,PF &&
+	git -c core.symlinks=true checkout -- PF &&
+	cmd //c dir >actual &&
+	grep "<SYMLINKD\\?> *PF *\\[\\\\Program Files\\]" actual
+'
+
 test_done

From c8672507b3df35ce386191b2816dffdc66e33b8a Mon Sep 17 00:00:00 2001
From: Jeff Hostetler <jeffhost@microsoft.com>
Date: Fri, 25 Mar 2022 16:56:04 -0400
Subject: [PATCH 190/259] compat/fsmonitor/fsm-*-win32: support long paths

Update wchar_t buffers to use MAX_LONG_PATH instead of MAX_PATH and call
xutftowcs_long_path() in the Win32 backend source files.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 compat/fsmonitor/fsm-health-win32.c     |  6 +++---
 compat/fsmonitor/fsm-listen-win32.c     | 18 +++++++++---------
 compat/fsmonitor/fsm-path-utils-win32.c |  8 ++++----
 3 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/compat/fsmonitor/fsm-health-win32.c b/compat/fsmonitor/fsm-health-win32.c
index 2aa8c219acee4d..4b53360d194105 100644
--- a/compat/fsmonitor/fsm-health-win32.c
+++ b/compat/fsmonitor/fsm-health-win32.c
@@ -34,7 +34,7 @@ struct fsm_health_data
 
 	struct wt_moved
 	{
-		wchar_t wpath[MAX_PATH + 1];
+		wchar_t wpath[MAX_LONG_PATH + 1];
 		BY_HANDLE_FILE_INFORMATION bhfi;
 	} wt_moved;
 };
@@ -143,8 +143,8 @@ static int has_worktree_moved(struct fsmonitor_daemon_state *state,
 		return 0;
 
 	case CTX_INIT:
-		if (xutftowcs_path(data->wt_moved.wpath,
-				   state->path_worktree_watch.buf) < 0) {
+		if (xutftowcs_long_path(data->wt_moved.wpath,
+					state->path_worktree_watch.buf) < 0) {
 			error(_("could not convert to wide characters: '%s'"),
 			      state->path_worktree_watch.buf);
 			return -1;
diff --git a/compat/fsmonitor/fsm-listen-win32.c b/compat/fsmonitor/fsm-listen-win32.c
index 5a21dade7b8659..98b73f63170b16 100644
--- a/compat/fsmonitor/fsm-listen-win32.c
+++ b/compat/fsmonitor/fsm-listen-win32.c
@@ -28,7 +28,7 @@ struct one_watch
 	DWORD count;
 
 	struct strbuf path;
-	wchar_t wpath_longname[MAX_PATH + 1];
+	wchar_t wpath_longname[MAX_LONG_PATH + 1];
 	DWORD wpath_longname_len;
 
 	HANDLE hDir;
@@ -131,8 +131,8 @@ static int normalize_path_in_utf8(wchar_t *wpath, DWORD wpath_len,
  */
 static void check_for_shortnames(struct one_watch *watch)
 {
-	wchar_t buf_in[MAX_PATH + 1];
-	wchar_t buf_out[MAX_PATH + 1];
+	wchar_t buf_in[MAX_LONG_PATH + 1];
+	wchar_t buf_out[MAX_LONG_PATH + 1];
 	wchar_t *last;
 	wchar_t *p;
 
@@ -197,8 +197,8 @@ static enum get_relative_result get_relative_longname(
 	const wchar_t *wpath, DWORD wpath_len,
 	wchar_t *wpath_longname, size_t bufsize_wpath_longname)
 {
-	wchar_t buf_in[2 * MAX_PATH + 1];
-	wchar_t buf_out[MAX_PATH + 1];
+	wchar_t buf_in[2 * MAX_LONG_PATH + 1];
+	wchar_t buf_out[MAX_LONG_PATH + 1];
 	DWORD root_len;
 	DWORD out_len;
 
@@ -298,10 +298,10 @@ static struct one_watch *create_watch(const char *path)
 		FILE_SHARE_WRITE | FILE_SHARE_READ | FILE_SHARE_DELETE;
 	HANDLE hDir;
 	DWORD len_longname;
-	wchar_t wpath[MAX_PATH + 1];
-	wchar_t wpath_longname[MAX_PATH + 1];
+	wchar_t wpath[MAX_LONG_PATH + 1];
+	wchar_t wpath_longname[MAX_LONG_PATH + 1];
 
-	if (xutftowcs_path(wpath, path) < 0) {
+	if (xutftowcs_long_path(wpath, path) < 0) {
 		error(_("could not convert to wide characters: '%s'"), path);
 		return NULL;
 	}
@@ -545,7 +545,7 @@ static int process_worktree_events(struct fsmonitor_daemon_state *state)
 	struct string_list cookie_list = STRING_LIST_INIT_DUP;
 	struct fsmonitor_batch *batch = NULL;
 	const char *p = watch->buffer;
-	wchar_t wpath_longname[MAX_PATH + 1];
+	wchar_t wpath_longname[MAX_LONG_PATH + 1];
 
 	/*
 	 * If the kernel gets more events than will fit in the kernel
diff --git a/compat/fsmonitor/fsm-path-utils-win32.c b/compat/fsmonitor/fsm-path-utils-win32.c
index f4f9cc1f336720..c6eb065bde48b4 100644
--- a/compat/fsmonitor/fsm-path-utils-win32.c
+++ b/compat/fsmonitor/fsm-path-utils-win32.c
@@ -69,8 +69,8 @@ static int check_remote_protocol(wchar_t *wpath)
  */
 int fsmonitor__get_fs_info(const char *path, struct fs_info *fs_info)
 {
-	wchar_t wpath[MAX_PATH];
-	wchar_t wfullpath[MAX_PATH];
+	wchar_t wpath[MAX_LONG_PATH];
+	wchar_t wfullpath[MAX_LONG_PATH];
 	size_t wlen;
 	UINT driveType;
 
@@ -78,7 +78,7 @@ int fsmonitor__get_fs_info(const char *path, struct fs_info *fs_info)
 	 * Do everything in wide chars because the drive letter might be
 	 * a multi-byte sequence.  See win32_has_dos_drive_prefix().
 	 */
-	if (xutftowcs_path(wpath, path) < 0) {
+	if (xutftowcs_long_path(wpath, path) < 0) {
 		return -1;
 	}
 
@@ -97,7 +97,7 @@ int fsmonitor__get_fs_info(const char *path, struct fs_info *fs_info)
 	 * slashes to backslashes.  This is essential to get GetDriveTypeW()
 	 * correctly handle some UNC "\\server\share\..." paths.
 	 */
-	if (!GetFullPathNameW(wpath, MAX_PATH, wfullpath, NULL)) {
+	if (!GetFullPathNameW(wpath, MAX_LONG_PATH, wfullpath, NULL)) {
 		return -1;
 	}
 

From 21c96acb4fc3f2501ae5e83a870078299689c0d3 Mon Sep 17 00:00:00 2001
From: Ben Boeckel <mathstuf@gmail.com>
Date: Fri, 22 Apr 2022 09:06:23 -0400
Subject: [PATCH 191/259] clean: suggest using `core.longPaths` if paths are
 too long to remove

On Windows, git repositories may have extra files which need cleaned
(e.g., a build directory) that may be arbitrarily deep. Suggest using
`core.longPaths` if such situations are encountered.

Fixes: #2715
Signed-off-by: Ben Boeckel <mathstuf@gmail.com>
---
 Documentation/config/advice.txt |  3 +++
 advice.c                        |  1 +
 advice.h                        |  1 +
 builtin/clean.c                 | 13 +++++++++++++
 4 files changed, 18 insertions(+)

diff --git a/Documentation/config/advice.txt b/Documentation/config/advice.txt
index 0ba89898207f0c..5d716c6b2871b6 100644
--- a/Documentation/config/advice.txt
+++ b/Documentation/config/advice.txt
@@ -58,6 +58,9 @@ advice.*::
 		set their identity configuration.
 	mergeConflict::
 		Shown when various commands stop because of conflicts.
+	nameTooLong::
+		Advice shown if a filepath operation is attempted where the
+		path was too long.
 	nestedTag::
 		Shown when a user attempts to recursively tag a tag object.
 	pushAlreadyExists::
diff --git a/advice.c b/advice.c
index 6b879d805c0304..3f4fed422f1e8d 100644
--- a/advice.c
+++ b/advice.c
@@ -59,6 +59,7 @@ static struct {
 	[ADVICE_IGNORED_HOOK]				= { "ignoredHook" },
 	[ADVICE_IMPLICIT_IDENTITY]			= { "implicitIdentity" },
 	[ADVICE_MERGE_CONFLICT]				= { "mergeConflict" },
+	[ADVICE_NAME_TOO_LONG]				= { "nameTooLong" },
 	[ADVICE_NESTED_TAG]				= { "nestedTag" },
 	[ADVICE_OBJECT_NAME_WARNING]			= { "objectNameWarning" },
 	[ADVICE_PUSH_ALREADY_EXISTS]			= { "pushAlreadyExists" },
diff --git a/advice.h b/advice.h
index d7466bc0ef2026..972c46c3c434e6 100644
--- a/advice.h
+++ b/advice.h
@@ -26,6 +26,7 @@ enum advice_type {
 	ADVICE_IGNORED_HOOK,
 	ADVICE_IMPLICIT_IDENTITY,
 	ADVICE_MERGE_CONFLICT,
+	ADVICE_NAME_TOO_LONG,
 	ADVICE_NESTED_TAG,
 	ADVICE_OBJECT_NAME_WARNING,
 	ADVICE_PUSH_ALREADY_EXISTS,
diff --git a/builtin/clean.c b/builtin/clean.c
index e50e1bb39d8fe1..5f6ba1cd7891a9 100644
--- a/builtin/clean.c
+++ b/builtin/clean.c
@@ -23,6 +23,7 @@
 #include "pathspec.h"
 #include "help.h"
 #include "prompt.h"
+#include "advice.h"
 
 static int require_force = -1; /* unset */
 static int interactive;
@@ -218,6 +219,9 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 			quote_path(path->buf, prefix, &quoted, 0);
 			errno = saved_errno;
 			warning_errno(_(msg_warn_remove_failed), quoted.buf);
+			if (saved_errno == ENAMETOOLONG) {
+				advise_if_enabled(ADVICE_NAME_TOO_LONG, _("Setting `core.longPaths` may allow the deletion to succeed."));
+			}
 			*dir_gone = 0;
 		}
 		ret = res;
@@ -253,6 +257,9 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 				quote_path(path->buf, prefix, &quoted, 0);
 				errno = saved_errno;
 				warning_errno(_(msg_warn_remove_failed), quoted.buf);
+				if (saved_errno == ENAMETOOLONG) {
+					advise_if_enabled(ADVICE_NAME_TOO_LONG, _("Setting `core.longPaths` may allow the deletion to succeed."));
+				}
 				*dir_gone = 0;
 				ret = 1;
 			}
@@ -296,6 +303,9 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 				quote_path(path->buf, prefix, &quoted, 0);
 				errno = saved_errno;
 				warning_errno(_(msg_warn_remove_failed), quoted.buf);
+				if (saved_errno == ENAMETOOLONG) {
+					advise_if_enabled(ADVICE_NAME_TOO_LONG, _("Setting `core.longPaths` may allow the deletion to succeed."));
+				}
 				*dir_gone = 0;
 				ret = 1;
 			}
@@ -1105,6 +1115,9 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
 				qname = quote_path(item->string, NULL, &buf, 0);
 				errno = saved_errno;
 				warning_errno(_(msg_warn_remove_failed), qname);
+				if (saved_errno == ENAMETOOLONG) {
+					advise_if_enabled(ADVICE_NAME_TOO_LONG, _("Setting `core.longPaths` may allow the deletion to succeed."));
+				}
 				errors++;
 			} else if (!quiet) {
 				qname = quote_path(item->string, NULL, &buf, 0);

From a77944ab887d431b2258b78da7bdcbc5b16d8c9a Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 6 Sep 2016 09:50:33 +0200
Subject: [PATCH 192/259] Unbreak interactive GPG prompt upon signing

With the recent update in efee955 (gpg-interface: check gpg signature
creation status, 2016-06-17), we ask GPG to send all status updates to
stderr, and then catch the stderr in an strbuf.

But GPG might fail, and send error messages to stderr. And we simply
do not show them to the user.

Even worse: this swallows any interactive prompt for a passphrase. And
detaches stderr from the tty so that the passphrase cannot be read.

So while the first problem could be fixed (by printing the captured
stderr upon error), the second problem cannot be easily fixed, and
presents a major regression.

So let's just revert commit efee9553a4f97b2ecd8f49be19606dd4cf7d9c28.

This fixes https://github.com/git-for-windows/git/issues/871

Cc: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 gpg-interface.c | 21 +++------------------
 t/t7004-tag.sh  | 31 -------------------------------
 2 files changed, 3 insertions(+), 49 deletions(-)

diff --git a/gpg-interface.c b/gpg-interface.c
index 5c824aeb257cb9..ffa3ce0787a359 100644
--- a/gpg-interface.c
+++ b/gpg-interface.c
@@ -972,12 +972,9 @@ static int sign_buffer_gpg(struct strbuf *buffer, struct strbuf *signature,
 	struct child_process gpg = CHILD_PROCESS_INIT;
 	int ret;
 	size_t bottom;
-	const char *cp;
-	struct strbuf gpg_status = STRBUF_INIT;
 
 	strvec_pushl(&gpg.args,
 		     use_format->program,
-		     "--status-fd=2",
 		     "-bsau", signing_key,
 		     NULL);
 
@@ -989,23 +986,11 @@ static int sign_buffer_gpg(struct strbuf *buffer, struct strbuf *signature,
 	 */
 	sigchain_push(SIGPIPE, SIG_IGN);
 	ret = pipe_command(&gpg, buffer->buf, buffer->len,
-			   signature, 1024, &gpg_status, 0);
+			   signature, 1024, NULL, 0);
 	sigchain_pop(SIGPIPE);
 
-	for (cp = gpg_status.buf;
-	     cp && (cp = strstr(cp, "[GNUPG:] SIG_CREATED "));
-	     cp++) {
-		if (cp == gpg_status.buf || cp[-1] == '\n')
-			break; /* found */
-	}
-	ret |= !cp;
-	if (ret) {
-		error(_("gpg failed to sign the data:\n%s"),
-		      gpg_status.len ? gpg_status.buf : "(no gpg output)");
-		strbuf_release(&gpg_status);
-		return -1;
-	}
-	strbuf_release(&gpg_status);
+	if (ret || signature->len == bottom)
+		return error(_("gpg failed to sign the data"));
 
 	/* Strip CR from the line endings, in case we are on Windows. */
 	remove_cr_after(signature, bottom);
diff --git a/t/t7004-tag.sh b/t/t7004-tag.sh
index fa6336edf98350..e253b520f237a4 100755
--- a/t/t7004-tag.sh
+++ b/t/t7004-tag.sh
@@ -1517,30 +1517,6 @@ test_expect_success GPG \
 	'test_config user.signingkey BobTheMouse &&
 	test_must_fail git tag -s -m tail tag-gpg-failure'
 
-# try to produce invalid signature
-test_expect_success GPG \
-	'git tag -s fails if gpg is misconfigured (bad signature format)' \
-	'test_config gpg.program echo &&
-	 test_must_fail git tag -s -m tail tag-gpg-failure'
-
-# try to produce invalid signature
-test_expect_success GPG 'git verifies tag is valid with double signature' '
-	git tag -s -m tail tag-gpg-double-sig &&
-	git cat-file tag tag-gpg-double-sig >tag &&
-	othersigheader=$(test_oid othersigheader) &&
-	sed -ne "/^\$/q;p" tag >new-tag &&
-	cat <<-EOM >>new-tag &&
-	$othersigheader -----BEGIN PGP SIGNATURE-----
-	 someinvaliddata
-	 -----END PGP SIGNATURE-----
-	EOM
-	sed -e "1,/^tagger/d" tag >>new-tag &&
-	new_tag=$(git hash-object -t tag -w new-tag) &&
-	git update-ref refs/tags/tag-gpg-double-sig $new_tag &&
-	git verify-tag tag-gpg-double-sig &&
-	git fsck
-'
-
 # try to sign with bad user.signingkey
 test_expect_success GPGSM \
 	'git tag -s fails if gpgsm is misconfigured (bad key)' \
@@ -1548,13 +1524,6 @@ test_expect_success GPGSM \
 	 test_config gpg.format x509 &&
 	 test_must_fail git tag -s -m tail tag-gpg-failure'
 
-# try to produce invalid signature
-test_expect_success GPGSM \
-	'git tag -s fails if gpgsm is misconfigured (bad signature format)' \
-	'test_config gpg.x509.program echo &&
-	 test_config gpg.format x509 &&
-	 test_must_fail git tag -s -m tail tag-gpg-failure'
-
 # try to verify without gpg:
 
 rm -rf gpghome

From f2c265b8ce6f3d39761096af2663956a42c92356 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Mon, 11 May 2015 19:54:23 +0200
Subject: [PATCH 193/259] strbuf_readlink: don't call readlink twice if hint is
 the exact link size

strbuf_readlink() calls readlink() twice if the hint argument specifies the
exact size of the link target (e.g. by passing stat.st_size as returned by
lstat()). This is necessary because 'readlink(..., hint) == hint' could
mean that the buffer was too small.

Use hint + 1 as buffer size to prevent this.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 strbuf.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/strbuf.c b/strbuf.c
index 3d2189a7f648dc..96779071e03343 100644
--- a/strbuf.c
+++ b/strbuf.c
@@ -574,12 +574,12 @@ int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 	while (hint < STRBUF_MAXLINK) {
 		ssize_t len;
 
-		strbuf_grow(sb, hint);
-		len = readlink(path, sb->buf, hint);
+		strbuf_grow(sb, hint + 1);
+		len = readlink(path, sb->buf, hint + 1);
 		if (len < 0) {
 			if (errno != ERANGE)
 				break;
-		} else if (len < hint) {
+		} else if (len <= hint) {
 			strbuf_setlen(sb, len);
 			return 0;
 		}

From 25eee7c1f533a2fff2dbef153b17242b4f455db4 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Mon, 11 May 2015 22:15:40 +0200
Subject: [PATCH 194/259] strbuf_readlink: support link targets that exceed
 PATH_MAX

strbuf_readlink() refuses to read link targets that exceed PATH_MAX (even
if a sufficient size was specified by the caller).

As some platforms support longer paths, remove this restriction (similar
to strbuf_getcwd()).

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 strbuf.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/strbuf.c b/strbuf.c
index 96779071e03343..9b427403c46c2b 100644
--- a/strbuf.c
+++ b/strbuf.c
@@ -562,8 +562,6 @@ ssize_t strbuf_write(struct strbuf *sb, FILE *f)
 	return sb->len ? fwrite(sb->buf, 1, sb->len, f) : 0;
 }
 
-#define STRBUF_MAXLINK (2*PATH_MAX)
-
 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 {
 	size_t oldalloc = sb->alloc;
@@ -571,7 +569,7 @@ int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 	if (hint < 32)
 		hint = 32;
 
-	while (hint < STRBUF_MAXLINK) {
+	for (;;) {
 		ssize_t len;
 
 		strbuf_grow(sb, hint + 1);

From 1925b124edb4888d43a53c41acca1c28f62b69c8 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Mon, 11 May 2015 19:58:14 +0200
Subject: [PATCH 195/259] lockfile.c: use is_dir_sep() instead of hardcoded '/'
 checks

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 lockfile.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lockfile.c b/lockfile.c
index 1d5ed016828746..67082a9caaeb18 100644
--- a/lockfile.c
+++ b/lockfile.c
@@ -19,14 +19,14 @@ static void trim_last_path_component(struct strbuf *path)
 	int i = path->len;
 
 	/* back up past trailing slashes, if any */
-	while (i && path->buf[i - 1] == '/')
+	while (i && is_dir_sep(path->buf[i - 1]))
 		i--;
 
 	/*
 	 * then go backwards until a slash, or the beginning of the
 	 * string
 	 */
-	while (i && path->buf[i - 1] != '/')
+	while (i && !is_dir_sep(path->buf[i - 1]))
 		i--;
 
 	strbuf_setlen(path, i);

From b40940a436bd2c0a8dcb2e80bd809f9faadee0ca Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Tue, 12 May 2015 11:09:01 +0200
Subject: [PATCH 196/259] Win32: don't call GetFileAttributes twice in
 mingw_lstat()

GetFileAttributes cannot handle paths with trailing dir separator. The
current [l]stat implementation calls GetFileAttributes twice if the path
has trailing slashes (first with the original path passed to [l]stat, and
and a second time with a path copy with trailing '/' removed).

With Unicode conversion, we get the length of the path for free and also
have a (wide char) buffer that can be modified.

Remove trailing directory separators before calling the Win32 API.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/mingw.c | 48 ++++++++++++------------------------------------
 1 file changed, 12 insertions(+), 36 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 92c8140841d6f2..bacecc82d1427e 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -874,8 +874,17 @@ static int do_lstat(int follow, const char *file_name, struct stat *buf)
 {
 	WIN32_FILE_ATTRIBUTE_DATA fdata;
 	wchar_t wfilename[MAX_LONG_PATH];
-	if (xutftowcs_long_path(wfilename, file_name) < 0)
+	int wlen = xutftowcs_long_path(wfilename, file_name);
+	if (wlen < 0)
+		return -1;
+
+	/* strip trailing '/', or GetFileAttributes will fail */
+	while (wlen && is_dir_sep(wfilename[wlen - 1]))
+		wfilename[--wlen] = 0;
+	if (!wlen) {
+		errno = ENOENT;
 		return -1;
+	}
 
 	if (GetFileAttributesExW(wfilename, GetFileExInfoStandard, &fdata)) {
 		buf->st_ino = 0;
@@ -936,39 +945,6 @@ static int do_lstat(int follow, const char *file_name, struct stat *buf)
 	return -1;
 }
 
-/* We provide our own lstat/fstat functions, since the provided
- * lstat/fstat functions are so slow. These stat functions are
- * tailored for Git's usage (read: fast), and are not meant to be
- * complete. Note that Git stat()s are redirected to mingw_lstat()
- * too, since Windows doesn't really handle symlinks that well.
- */
-static int do_stat_internal(int follow, const char *file_name, struct stat *buf)
-{
-	int namelen;
-	char alt_name[MAX_LONG_PATH];
-
-	if (!do_lstat(follow, file_name, buf))
-		return 0;
-
-	/* if file_name ended in a '/', Windows returned ENOENT;
-	 * try again without trailing slashes
-	 */
-	if (errno != ENOENT)
-		return -1;
-
-	namelen = strlen(file_name);
-	if (namelen && file_name[namelen-1] != '/')
-		return -1;
-	while (namelen && file_name[namelen-1] == '/')
-		--namelen;
-	if (!namelen || namelen >= MAX_LONG_PATH)
-		return -1;
-
-	memcpy(alt_name, file_name, namelen);
-	alt_name[namelen] = 0;
-	return do_lstat(follow, alt_name, buf);
-}
-
 int (*lstat)(const char *file_name, struct stat *buf) = mingw_lstat;
 
 static int get_file_info_by_handle(HANDLE hnd, struct stat *buf)
@@ -996,11 +972,11 @@ static int get_file_info_by_handle(HANDLE hnd, struct stat *buf)
 
 int mingw_lstat(const char *file_name, struct stat *buf)
 {
-	return do_stat_internal(0, file_name, buf);
+	return do_lstat(0, file_name, buf);
 }
 int mingw_stat(const char *file_name, struct stat *buf)
 {
-	return do_stat_internal(1, file_name, buf);
+	return do_lstat(1, file_name, buf);
 }
 
 int mingw_fstat(int fd, struct stat *buf)

From e22994dff5085f536f4a224d1f7ac1155d7e08e1 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sat, 16 May 2015 01:18:14 +0200
Subject: [PATCH 197/259] Win32: implement stat() with symlink support

With respect to symlinks, the current stat() implementation is almost the
same as lstat(): except for the file type (st_mode & S_IFMT), it returns
information about the link rather than the target.

Implement stat by opening the file with as little permissions as possible
and calling GetFileInformationByHandle on it. This way, all link resoltion
is handled by the Windows file system layer.

If symlinks are disabled, use lstat() as before, but fail with ELOOP if a
symlink would have to be resolved.

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index bacecc82d1427e..52fb729ada4b3d 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -974,9 +974,26 @@ int mingw_lstat(const char *file_name, struct stat *buf)
 {
 	return do_lstat(0, file_name, buf);
 }
+
 int mingw_stat(const char *file_name, struct stat *buf)
 {
-	return do_lstat(1, file_name, buf);
+	wchar_t wfile_name[MAX_LONG_PATH];
+	HANDLE hnd;
+	int result;
+
+	/* open the file and let Windows resolve the links */
+	if (xutftowcs_long_path(wfile_name, file_name) < 0)
+		return -1;
+	hnd = CreateFileW(wfile_name, 0,
+			FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
+			OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+	if (hnd == INVALID_HANDLE_VALUE) {
+		errno = err_win_to_posix(GetLastError());
+		return -1;
+	}
+	result = get_file_info_by_handle(hnd, buf);
+	CloseHandle(hnd);
+	return result;
 }
 
 int mingw_fstat(int fd, struct stat *buf)

From a05b02798bd70ca6e7e4e1ef49b77f1f84436f5a Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Tue, 12 May 2015 00:58:39 +0200
Subject: [PATCH 198/259] Win32: remove separate do_lstat() function

With the new mingw_stat() implementation, do_lstat() is only called from
mingw_lstat() (with follow == 0). Remove the extra function and the old
mingw_stat()-specific (follow == 1) logic.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/mingw.c | 22 ++--------------------
 1 file changed, 2 insertions(+), 20 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 52fb729ada4b3d..3bd08565626897 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -863,14 +863,7 @@ static int has_valid_directory_prefix(wchar_t *wfilename)
 	return 1;
 }
 
-/* We keep the do_lstat code in a separate function to avoid recursion.
- * When a path ends with a slash, the stat will fail with ENOENT. In
- * this case, we strip the trailing slashes and stat again.
- *
- * If follow is true then act like stat() and report on the link
- * target. Otherwise report on the link itself.
- */
-static int do_lstat(int follow, const char *file_name, struct stat *buf)
+int mingw_lstat(const char *file_name, struct stat *buf)
 {
 	WIN32_FILE_ATTRIBUTE_DATA fdata;
 	wchar_t wfilename[MAX_LONG_PATH];
@@ -904,13 +897,7 @@ static int do_lstat(int follow, const char *file_name, struct stat *buf)
 			if (handle != INVALID_HANDLE_VALUE) {
 				if ((findbuf.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) &&
 						(findbuf.dwReserved0 == IO_REPARSE_TAG_SYMLINK)) {
-					if (follow) {
-						char buffer[MAXIMUM_REPARSE_DATA_BUFFER_SIZE];
-						buf->st_size = readlink(file_name, buffer, MAXIMUM_REPARSE_DATA_BUFFER_SIZE);
-					} else {
-						buf->st_mode = S_IFLNK;
-					}
-					buf->st_mode |= S_IREAD;
+					buf->st_mode = S_IFLNK | S_IREAD;
 					if (!(findbuf.dwFileAttributes & FILE_ATTRIBUTE_READONLY))
 						buf->st_mode |= S_IWRITE;
 				}
@@ -970,11 +957,6 @@ static int get_file_info_by_handle(HANDLE hnd, struct stat *buf)
 	return 0;
 }
 
-int mingw_lstat(const char *file_name, struct stat *buf)
-{
-	return do_lstat(0, file_name, buf);
-}
-
 int mingw_stat(const char *file_name, struct stat *buf)
 {
 	wchar_t wfile_name[MAX_LONG_PATH];

From 6ac21c8c083dbc4c6a41faf44ca76d413670e0cf Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sun, 24 May 2015 00:17:56 +0200
Subject: [PATCH 199/259] Win32: let mingw_lstat() error early upon problems
 with reparse points

When obtaining lstat information for reparse points, we need to call
FindFirstFile() in addition to GetFileInformationEx() to obtain the type
of the reparse point (symlink, mount point etc.). However, currently there
is no error handling whatsoever if FindFirstFile() fails.

Call FindFirstFile() before modifying the stat *buf output parameter and
error out if the call fails.

Note: The FindFirstFile() return value includes all the data that we get
from GetFileAttributesEx(), so we could replace GetFileAttributesEx() with
FindFirstFile(). We don't do that because GetFileAttributesEx() is about
twice as fast for single files. I.e. we only pay the extra cost of calling
FindFirstFile() in the rare case that we encounter a reparse point.

Note: The indentation of the remaining reparse point code will be fixed in
the next patch.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/mingw.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 3bd08565626897..548b2d1b4e93b2 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -866,6 +866,7 @@ static int has_valid_directory_prefix(wchar_t *wfilename)
 int mingw_lstat(const char *file_name, struct stat *buf)
 {
 	WIN32_FILE_ATTRIBUTE_DATA fdata;
+	WIN32_FIND_DATAW findbuf = { 0 };
 	wchar_t wfilename[MAX_LONG_PATH];
 	int wlen = xutftowcs_long_path(wfilename, file_name);
 	if (wlen < 0)
@@ -880,6 +881,13 @@ int mingw_lstat(const char *file_name, struct stat *buf)
 	}
 
 	if (GetFileAttributesExW(wfilename, GetFileExInfoStandard, &fdata)) {
+		/* for reparse points, use FindFirstFile to get the reparse tag */
+		if (fdata.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
+			HANDLE handle = FindFirstFileW(wfilename, &findbuf);
+			if (handle == INVALID_HANDLE_VALUE)
+				goto error;
+			FindClose(handle);
+		}
 		buf->st_ino = 0;
 		buf->st_gid = 0;
 		buf->st_uid = 0;
@@ -892,20 +900,16 @@ int mingw_lstat(const char *file_name, struct stat *buf)
 		filetime_to_timespec(&(fdata.ftLastWriteTime), &(buf->st_mtim));
 		filetime_to_timespec(&(fdata.ftCreationTime), &(buf->st_ctim));
 		if (fdata.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
-			WIN32_FIND_DATAW findbuf;
-			HANDLE handle = FindFirstFileW(wfilename, &findbuf);
-			if (handle != INVALID_HANDLE_VALUE) {
 				if ((findbuf.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) &&
 						(findbuf.dwReserved0 == IO_REPARSE_TAG_SYMLINK)) {
 					buf->st_mode = S_IFLNK | S_IREAD;
 					if (!(findbuf.dwFileAttributes & FILE_ATTRIBUTE_READONLY))
 						buf->st_mode |= S_IWRITE;
 				}
-				FindClose(handle);
-			}
 		}
 		return 0;
 	}
+error:
 	switch (GetLastError()) {
 	case ERROR_ACCESS_DENIED:
 	case ERROR_SHARING_VIOLATION:

From 0240aa243921b8da5c310d203df82fcb4915cf75 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Tue, 10 Jan 2017 23:21:56 +0100
Subject: [PATCH 200/259] mingw: teach fscache and dirent about symlinks

Move S_IFLNK detection to file_attr_to_st_mode() and reuse it in fscache.

Implement DT_LNK detection in dirent.c and the fscache readdir version.

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c         | 13 +++----------
 compat/win32.h         |  6 ++++--
 compat/win32/dirent.c  |  5 ++++-
 compat/win32/fscache.c | 11 +++++++----
 4 files changed, 18 insertions(+), 17 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 548b2d1b4e93b2..68d53367015ccc 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -892,21 +892,14 @@ int mingw_lstat(const char *file_name, struct stat *buf)
 		buf->st_gid = 0;
 		buf->st_uid = 0;
 		buf->st_nlink = 1;
-		buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
+		buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes,
+				findbuf.dwReserved0);
 		buf->st_size = fdata.nFileSizeLow |
 			(((off_t)fdata.nFileSizeHigh)<<32);
 		buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 		filetime_to_timespec(&(fdata.ftLastAccessTime), &(buf->st_atim));
 		filetime_to_timespec(&(fdata.ftLastWriteTime), &(buf->st_mtim));
 		filetime_to_timespec(&(fdata.ftCreationTime), &(buf->st_ctim));
-		if (fdata.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
-				if ((findbuf.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) &&
-						(findbuf.dwReserved0 == IO_REPARSE_TAG_SYMLINK)) {
-					buf->st_mode = S_IFLNK | S_IREAD;
-					if (!(findbuf.dwFileAttributes & FILE_ATTRIBUTE_READONLY))
-						buf->st_mode |= S_IWRITE;
-				}
-		}
 		return 0;
 	}
 error:
@@ -951,7 +944,7 @@ static int get_file_info_by_handle(HANDLE hnd, struct stat *buf)
 	buf->st_gid = 0;
 	buf->st_uid = 0;
 	buf->st_nlink = 1;
-	buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
+	buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes, 0);
 	buf->st_size = fdata.nFileSizeLow |
 		(((off_t)fdata.nFileSizeHigh)<<32);
 	buf->st_dev = buf->st_rdev = 0; /* not used by Git */
diff --git a/compat/win32.h b/compat/win32.h
index a97e880757b6f1..671bcc81f93351 100644
--- a/compat/win32.h
+++ b/compat/win32.h
@@ -6,10 +6,12 @@
 #include <windows.h>
 #endif
 
-static inline int file_attr_to_st_mode (DWORD attr)
+static inline int file_attr_to_st_mode (DWORD attr, DWORD tag)
 {
 	int fMode = S_IREAD;
-	if (attr & FILE_ATTRIBUTE_DIRECTORY)
+	if ((attr & FILE_ATTRIBUTE_REPARSE_POINT) && tag == IO_REPARSE_TAG_SYMLINK)
+		fMode |= S_IFLNK;
+	else if (attr & FILE_ATTRIBUTE_DIRECTORY)
 		fMode |= S_IFDIR;
 	else
 		fMode |= S_IFREG;
diff --git a/compat/win32/dirent.c b/compat/win32/dirent.c
index c9fe2454efc01c..87063101f57202 100644
--- a/compat/win32/dirent.c
+++ b/compat/win32/dirent.c
@@ -18,7 +18,10 @@ static inline void finddata2dirent(struct dirent *ent, WIN32_FIND_DATAW *fdata)
 	xwcstoutf(ent->d_name, fdata->cFileName, MAX_PATH * 3);
 
 	/* Set file type, based on WIN32_FIND_DATA */
-	if (fdata->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
+	if ((fdata->dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT)
+			&& fdata->dwReserved0 == IO_REPARSE_TAG_SYMLINK)
+		ent->d_type = DT_LNK;
+	else if (fdata->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
 		ent->d_type = DT_DIR;
 	else
 		ent->d_type = DT_REG;
diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index 581808a64b6cd6..3016ae61dee5e0 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -202,10 +202,13 @@ static struct fsentry *fseentry_create_entry(struct fscache *cache,
 		fdata->FileAttributes & FILE_ATTRIBUTE_REPARSE_POINT ?
 		fdata->EaSize : 0;
 
-	fse->st_mode = file_attr_to_st_mode(fdata->FileAttributes);
-	fse->dirent.d_type = S_ISDIR(fse->st_mode) ? DT_DIR : DT_REG;
-	fse->u.s.st_size = fdata->EndOfFile.LowPart |
-		(((off_t)fdata->EndOfFile.HighPart) << 32);
+	fse->st_mode = file_attr_to_st_mode(fdata->FileAttributes,
+					    fdata->EaSize);
+	fse->dirent.d_type = S_ISREG(fse->st_mode) ? DT_REG :
+			S_ISDIR(fse->st_mode) ? DT_DIR : DT_LNK;
+	fse->u.s.st_size = S_ISLNK(fse->st_mode) ? MAX_LONG_PATH :
+			fdata->EndOfFile.LowPart |
+			(((off_t)fdata->EndOfFile.HighPart) << 32);
 	filetime_to_timespec((FILETIME *)&(fdata->LastAccessTime),
 			     &(fse->u.s.st_atim));
 	filetime_to_timespec((FILETIME *)&(fdata->LastWriteTime),

From d78d40ad4cda3b791d5c157be8b8265c5cab58ba Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sat, 16 May 2015 01:11:37 +0200
Subject: [PATCH 201/259] Win32: lstat(): return adequate stat.st_size for
 symlinks

Git typically doesn't trust the stat.st_size member of symlinks (e.g. see
strbuf_readlink()). However, some functions take shortcuts if st_size is 0
(e.g. diff_populate_filespec()).

In mingw_lstat() and fscache_lstat(), make sure to return an adequate size.

The extra overhead of opening and reading the reparse point to calculate
the exact size is not necessary, as git doesn't rely on the value anyway.

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 68d53367015ccc..8a8aeb8daca52f 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -894,8 +894,8 @@ int mingw_lstat(const char *file_name, struct stat *buf)
 		buf->st_nlink = 1;
 		buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes,
 				findbuf.dwReserved0);
-		buf->st_size = fdata.nFileSizeLow |
-			(((off_t)fdata.nFileSizeHigh)<<32);
+		buf->st_size = S_ISLNK(buf->st_mode) ? MAX_LONG_PATH :
+			fdata.nFileSizeLow | (((off_t) fdata.nFileSizeHigh) << 32);
 		buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 		filetime_to_timespec(&(fdata.ftLastAccessTime), &(buf->st_atim));
 		filetime_to_timespec(&(fdata.ftLastWriteTime), &(buf->st_mtim));

From 07ad87a6ad74eeabeda54af1d448b0c2e9283c5b Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Tue, 19 May 2015 21:48:55 +0200
Subject: [PATCH 202/259] Win32: factor out retry logic

The retry pattern is duplicated in three places. It also seems to be too
hard to use: mingw_unlink() and mingw_rmdir() duplicate the code to retry,
and both of them do so incompletely. They also do not restore errno if the
user answers 'no'.

Introduce a retry_ask_yes_no() helper function that handles retry with
small delay, asking the user, and restoring errno.

mingw_unlink: include _wchmod in the retry loop (which may fail if the
file is locked exclusively).

mingw_rmdir: include special error handling in the retry loop.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/mingw.c | 102 ++++++++++++++++++++++---------------------------
 1 file changed, 45 insertions(+), 57 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 8a8aeb8daca52f..5c1f94c3a23ee7 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -25,8 +25,6 @@
 
 #define HCAST(type, handle) ((type)(intptr_t)handle)
 
-static const int delay[] = { 0, 1, 10, 20, 40 };
-
 void open_in_gdb(void)
 {
 	static struct child_process cp = CHILD_PROCESS_INIT;
@@ -202,15 +200,12 @@ static int read_yes_no_answer(void)
 	return -1;
 }
 
-static int ask_yes_no_if_possible(const char *format, ...)
+static int ask_yes_no_if_possible(const char *format, va_list args)
 {
 	char question[4096];
 	const char *retry_hook;
-	va_list args;
 
-	va_start(args, format);
 	vsnprintf(question, sizeof(question), format, args);
-	va_end(args);
 
 	retry_hook = mingw_getenv("GIT_ASK_YESNO");
 	if (retry_hook) {
@@ -235,6 +230,31 @@ static int ask_yes_no_if_possible(const char *format, ...)
 	}
 }
 
+static int retry_ask_yes_no(int *tries, const char *format, ...)
+{
+	static const int delay[] = { 0, 1, 10, 20, 40 };
+	va_list args;
+	int result, saved_errno = errno;
+
+	if ((*tries) < ARRAY_SIZE(delay)) {
+		/*
+		 * We assume that some other process had the file open at the wrong
+		 * moment and retry. In order to give the other process a higher
+		 * chance to complete its operation, we give up our time slice now.
+		 * If we have to retry again, we do sleep a bit.
+		 */
+		Sleep(delay[*tries]);
+		(*tries)++;
+		return 1;
+	}
+
+	va_start(args, format);
+	result = ask_yes_no_if_possible(format, args);
+	va_end(args);
+	errno = saved_errno;
+	return result;
+}
+
 /* Windows only */
 enum hide_dotfiles_type {
 	HIDE_DOTFILES_FALSE = 0,
@@ -336,7 +356,7 @@ static wchar_t *normalize_ntpath(wchar_t *wbuf)
 
 int mingw_unlink(const char *pathname)
 {
-	int ret, tries = 0;
+	int tries = 0;
 	wchar_t wpathname[MAX_LONG_PATH];
 	if (xutftowcs_long_path(wpathname, pathname) < 0)
 		return -1;
@@ -344,26 +364,16 @@ int mingw_unlink(const char *pathname)
 	if (DeleteFileW(wpathname))
 		return 0;
 
-	/* read-only files cannot be removed */
-	_wchmod(wpathname, 0666);
-	while ((ret = _wunlink(wpathname)) == -1 && tries < ARRAY_SIZE(delay)) {
+	do {
+		/* read-only files cannot be removed */
+		_wchmod(wpathname, 0666);
+		if (!_wunlink(wpathname))
+			return 0;
 		if (!is_file_in_use_error(GetLastError()))
 			break;
-		/*
-		 * We assume that some other process had the source or
-		 * destination file open at the wrong moment and retry.
-		 * In order to give the other process a higher chance to
-		 * complete its operation, we give up our time slice now.
-		 * If we have to retry again, we do sleep a bit.
-		 */
-		Sleep(delay[tries]);
-		tries++;
-	}
-	while (ret == -1 && is_file_in_use_error(GetLastError()) &&
-	       ask_yes_no_if_possible("Unlink of file '%s' failed. "
-			"Should I try again?", pathname))
-	       ret = _wunlink(wpathname);
-	return ret;
+	} while (retry_ask_yes_no(&tries, "Unlink of file '%s' failed. "
+			"Should I try again?", pathname));
+	return -1;
 }
 
 static int is_dir_empty(const wchar_t *wpath)
@@ -390,7 +400,7 @@ static int is_dir_empty(const wchar_t *wpath)
 
 int mingw_rmdir(const char *pathname)
 {
-	int ret, tries = 0;
+	int tries = 0;
 	wchar_t wpathname[MAX_LONG_PATH];
 	struct stat st;
 
@@ -416,7 +426,11 @@ int mingw_rmdir(const char *pathname)
 	if (xutftowcs_long_path(wpathname, pathname) < 0)
 		return -1;
 
-	while ((ret = _wrmdir(wpathname)) == -1 && tries < ARRAY_SIZE(delay)) {
+	do {
+		if (!_wrmdir(wpathname)) {
+			invalidate_lstat_cache();
+			return 0;
+		}
 		if (!is_file_in_use_error(GetLastError()))
 			errno = err_win_to_posix(GetLastError());
 		if (errno != EACCES)
@@ -425,23 +439,9 @@ int mingw_rmdir(const char *pathname)
 			errno = ENOTEMPTY;
 			break;
 		}
-		/*
-		 * We assume that some other process had the source or
-		 * destination file open at the wrong moment and retry.
-		 * In order to give the other process a higher chance to
-		 * complete its operation, we give up our time slice now.
-		 * If we have to retry again, we do sleep a bit.
-		 */
-		Sleep(delay[tries]);
-		tries++;
-	}
-	while (ret == -1 && errno == EACCES && is_file_in_use_error(GetLastError()) &&
-	       ask_yes_no_if_possible("Deletion of directory '%s' failed. "
-			"Should I try again?", pathname))
-	       ret = _wrmdir(wpathname);
-	if (!ret)
-		invalidate_lstat_cache();
-	return ret;
+	} while (retry_ask_yes_no(&tries, "Deletion of directory '%s' failed. "
+			"Should I try again?", pathname));
+	return -1;
 }
 
 static inline int needs_hiding(const char *path)
@@ -2445,20 +2445,8 @@ int mingw_rename(const char *pold, const char *pnew)
 			SetFileAttributesW(wpnew, attrs);
 		}
 	}
-	if (tries < ARRAY_SIZE(delay) && gle == ERROR_ACCESS_DENIED) {
-		/*
-		 * We assume that some other process had the source or
-		 * destination file open at the wrong moment and retry.
-		 * In order to give the other process a higher chance to
-		 * complete its operation, we give up our time slice now.
-		 * If we have to retry again, we do sleep a bit.
-		 */
-		Sleep(delay[tries]);
-		tries++;
-		goto repeat;
-	}
 	if (gle == ERROR_ACCESS_DENIED &&
-	       ask_yes_no_if_possible("Rename from '%s' to '%s' failed. "
+	       retry_ask_yes_no(&tries, "Rename from '%s' to '%s' failed. "
 		       "Should I try again?", pold, pnew))
 		goto repeat;
 

From 4d77b6c8d04858e102776ca2c59506f35c54a4c0 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sun, 24 May 2015 01:55:05 +0200
Subject: [PATCH 203/259] Win32: change default of 'core.symlinks' to false

Symlinks on Windows don't work the same way as on Unix systems. E.g. there
are different types of symlinks for directories and files, creating
symlinks requires administrative privileges etc.

By default, disable symlink support on Windows. I.e. users explicitly have
to enable it with 'git config [--system|--global] core.symlinks true'.

The test suite ignores system / global config files. Allow testing *with*
symlink support by checking if native symlinks are enabled in MSys2 (via
'MSYS=winsymlinks:nativestrict').

Reminder: This would need to be changed if / when we find a way to run the
test suite in a non-MSys-based shell (e.g. dash).

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/mingw.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/compat/mingw.c b/compat/mingw.c
index 5c1f94c3a23ee7..6e4e1488e14392 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -3035,6 +3035,15 @@ static void setup_windows_environment(void)
 
 	if (!getenv("LC_ALL") && !getenv("LC_CTYPE") && !getenv("LANG"))
 		setenv("LC_CTYPE", "C.UTF-8", 1);
+
+	/*
+	 * Change 'core.symlinks' default to false, unless native symlinks are
+	 * enabled in MSys2 (via 'MSYS=winsymlinks:nativestrict'). Thus we can
+	 * run the test suite (which doesn't obey config files) with or without
+	 * symlink support.
+	 */
+	if (!(tmp = getenv("MSYS")) || !strstr(tmp, "winsymlinks:nativestrict"))
+		has_symlinks = 0;
 }
 
 static PSID get_current_user_sid(void)

From 93348ea27654406c63c148d6a074b1ab82bc66f3 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sat, 16 May 2015 00:32:03 +0200
Subject: [PATCH 204/259] Win32: add symlink-specific error codes

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/mingw.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/compat/mingw.c b/compat/mingw.c
index 6e4e1488e14392..1ffc5d537756aa 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -99,6 +99,7 @@ int err_win_to_posix(DWORD winerr)
 	case ERROR_INVALID_PARAMETER: error = EINVAL; break;
 	case ERROR_INVALID_PASSWORD: error = EPERM; break;
 	case ERROR_INVALID_PRIMARY_GROUP: error = EINVAL; break;
+	case ERROR_INVALID_REPARSE_DATA: error = EINVAL; break;
 	case ERROR_INVALID_SIGNAL_NUMBER: error = EINVAL; break;
 	case ERROR_INVALID_TARGET_HANDLE: error = EIO; break;
 	case ERROR_INVALID_WORKSTATION: error = EACCES; break;
@@ -113,6 +114,7 @@ int err_win_to_posix(DWORD winerr)
 	case ERROR_NEGATIVE_SEEK: error = ESPIPE; break;
 	case ERROR_NOACCESS: error = EFAULT; break;
 	case ERROR_NONE_MAPPED: error = EINVAL; break;
+	case ERROR_NOT_A_REPARSE_POINT: error = EINVAL; break;
 	case ERROR_NOT_ENOUGH_MEMORY: error = ENOMEM; break;
 	case ERROR_NOT_READY: error = EAGAIN; break;
 	case ERROR_NOT_SAME_DEVICE: error = EXDEV; break;
@@ -133,6 +135,9 @@ int err_win_to_posix(DWORD winerr)
 	case ERROR_PIPE_NOT_CONNECTED: error = EPIPE; break;
 	case ERROR_PRIVILEGE_NOT_HELD: error = EACCES; break;
 	case ERROR_READ_FAULT: error = EIO; break;
+	case ERROR_REPARSE_ATTRIBUTE_CONFLICT: error = EINVAL; break;
+	case ERROR_REPARSE_TAG_INVALID: error = EINVAL; break;
+	case ERROR_REPARSE_TAG_MISMATCH: error = EINVAL; break;
 	case ERROR_SEEK: error = EIO; break;
 	case ERROR_SEEK_ON_DEVICE: error = ESPIPE; break;
 	case ERROR_SHARING_BUFFER_EXCEEDED: error = ENFILE; break;

From fb3c384da0b00e3525b5214273206046bc0ce6ed Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sun, 24 May 2015 01:06:10 +0200
Subject: [PATCH 205/259] Win32: mingw_unlink: support symlinks to directories

_wunlink() / DeleteFileW() refuses to delete symlinks to directories. If
_wunlink() fails with ERROR_ACCESS_DENIED, try _wrmdir() as well.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/mingw.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/compat/mingw.c b/compat/mingw.c
index 1ffc5d537756aa..f474a4254d1897 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -376,6 +376,13 @@ int mingw_unlink(const char *pathname)
 			return 0;
 		if (!is_file_in_use_error(GetLastError()))
 			break;
+		/*
+		 * _wunlink() / DeleteFileW() for directory symlinks fails with
+		 * ERROR_ACCESS_DENIED (EACCES), so try _wrmdir() as well. This is the
+		 * same error we get if a file is in use (already checked above).
+		 */
+		if (!_wrmdir(wpathname))
+			return 0;
 	} while (retry_ask_yes_no(&tries, "Unlink of file '%s' failed. "
 			"Should I try again?", pathname));
 	return -1;

From 1802cf2f552e4c82043f52b79ae505b7732701df Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Tue, 19 May 2015 22:42:48 +0200
Subject: [PATCH 206/259] Win32: mingw_rename: support renaming symlinks

MSVCRT's _wrename() cannot rename symlinks over existing files: it returns
success without doing anything. Newer MSVCR*.dll versions probably do not
have this problem: according to CRT sources, they just call MoveFileEx()
with the MOVEFILE_COPY_ALLOWED flag.

Get rid of _wrename() and call MoveFileEx() with proper error handling.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/mingw.c | 38 +++++++++++++++++---------------------
 1 file changed, 17 insertions(+), 21 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index f474a4254d1897..879beb11449726 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2417,27 +2417,29 @@ int mingw_accept(int sockfd1, struct sockaddr *sa, socklen_t *sz)
 #undef rename
 int mingw_rename(const char *pold, const char *pnew)
 {
-	DWORD attrs, gle;
+	DWORD attrs = INVALID_FILE_ATTRIBUTES, gle;
 	int tries = 0;
 	wchar_t wpold[MAX_LONG_PATH], wpnew[MAX_LONG_PATH];
 	if (xutftowcs_long_path(wpold, pold) < 0 ||
 	    xutftowcs_long_path(wpnew, pnew) < 0)
 		return -1;
 
-	/*
-	 * Try native rename() first to get errno right.
-	 * It is based on MoveFile(), which cannot overwrite existing files.
-	 */
-	if (!_wrename(wpold, wpnew))
-		return 0;
-	if (errno != EEXIST)
-		return -1;
 repeat:
-	if (MoveFileExW(wpold, wpnew, MOVEFILE_REPLACE_EXISTING))
+	if (MoveFileExW(wpold, wpnew,
+			MOVEFILE_REPLACE_EXISTING | MOVEFILE_COPY_ALLOWED))
 		return 0;
-	/* TODO: translate more errors */
 	gle = GetLastError();
-	if (gle == ERROR_ACCESS_DENIED &&
+
+	/* revert file attributes on failure */
+	if (attrs != INVALID_FILE_ATTRIBUTES)
+		SetFileAttributesW(wpnew, attrs);
+
+	if (!is_file_in_use_error(gle)) {
+		errno = err_win_to_posix(gle);
+		return -1;
+	}
+
+	if (attrs == INVALID_FILE_ATTRIBUTES &&
 	    (attrs = GetFileAttributesW(wpnew)) != INVALID_FILE_ATTRIBUTES) {
 		if (attrs & FILE_ATTRIBUTE_DIRECTORY) {
 			DWORD attrsold = GetFileAttributesW(wpold);
@@ -2449,16 +2451,10 @@ int mingw_rename(const char *pold, const char *pnew)
 			return -1;
 		}
 		if ((attrs & FILE_ATTRIBUTE_READONLY) &&
-		    SetFileAttributesW(wpnew, attrs & ~FILE_ATTRIBUTE_READONLY)) {
-			if (MoveFileExW(wpold, wpnew, MOVEFILE_REPLACE_EXISTING))
-				return 0;
-			gle = GetLastError();
-			/* revert file attributes on failure */
-			SetFileAttributesW(wpnew, attrs);
-		}
+		    SetFileAttributesW(wpnew, attrs & ~FILE_ATTRIBUTE_READONLY))
+			goto repeat;
 	}
-	if (gle == ERROR_ACCESS_DENIED &&
-	       retry_ask_yes_no(&tries, "Rename from '%s' to '%s' failed. "
+	if (retry_ask_yes_no(&tries, "Rename from '%s' to '%s' failed. "
 		       "Should I try again?", pold, pnew))
 		goto repeat;
 

From b32ff9a22a366880f40e2003f9f8ed74212c8d34 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sun, 24 May 2015 01:17:31 +0200
Subject: [PATCH 207/259] Win32: mingw_chdir: change to symlink-resolved
 directory

If symlinks are enabled, resolve all symlinks when changing directories,
as required by POSIX.

Note: Git's real_path() function bases its link resolution algorithm on
this property of chdir(). Unfortunately, the current directory on Windows
is limited to only MAX_PATH (260) characters. Therefore using symlinks and
long paths in combination may be problematic.

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 879beb11449726..939299212045b1 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -829,7 +829,24 @@ int mingw_chdir(const char *dirname)
 	wchar_t wdirname[MAX_LONG_PATH];
 	if (xutftowcs_long_path(wdirname, dirname) < 0)
 		return -1;
-	result = _wchdir(wdirname);
+
+	if (has_symlinks) {
+		HANDLE hnd = CreateFileW(wdirname, 0,
+				FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
+				OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+		if (hnd == INVALID_HANDLE_VALUE) {
+			errno = err_win_to_posix(GetLastError());
+			return -1;
+		}
+		if (!GetFinalPathNameByHandleW(hnd, wdirname, ARRAY_SIZE(wdirname), 0)) {
+			errno = err_win_to_posix(GetLastError());
+			CloseHandle(hnd);
+			return -1;
+		}
+		CloseHandle(hnd);
+	}
+
+	result = _wchdir(normalize_ntpath(wdirname));
 	current_directory_len = GetCurrentDirectoryW(0, NULL);
 	return result;
 }

From 0137e5b1befea7a22c2f0d7e605ebfeccb359fc4 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sun, 24 May 2015 01:24:41 +0200
Subject: [PATCH 208/259] Win32: implement readlink()

Implement readlink() by reading NTFS reparse points. Works for symlinks
and directory junctions. If symlinks are disabled, fail with ENOSYS.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/mingw.c | 98 ++++++++++++++++++++++++++++++++++++++++++++++++++
 compat/mingw.h |  3 +-
 2 files changed, 99 insertions(+), 2 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 939299212045b1..530ef747032d23 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -5,6 +5,7 @@
 #include <sddl.h>
 #include <conio.h>
 #include <wchar.h>
+#include <winioctl.h>
 #include "../strbuf.h"
 #include "../run-command.h"
 #include "../abspath.h"
@@ -2752,6 +2753,103 @@ int link(const char *oldpath, const char *newpath)
 	return 0;
 }
 
+#ifndef _WINNT_H
+/*
+ * The REPARSE_DATA_BUFFER structure is defined in the Windows DDK (in
+ * ntifs.h) and in MSYS1's winnt.h (which defines _WINNT_H). So define
+ * it ourselves if we are on MSYS2 (whose winnt.h defines _WINNT_).
+ */
+typedef struct _REPARSE_DATA_BUFFER {
+	DWORD  ReparseTag;
+	WORD   ReparseDataLength;
+	WORD   Reserved;
+#ifndef _MSC_VER
+	_ANONYMOUS_UNION
+#endif
+	union {
+		struct {
+			WORD   SubstituteNameOffset;
+			WORD   SubstituteNameLength;
+			WORD   PrintNameOffset;
+			WORD   PrintNameLength;
+			ULONG  Flags;
+			WCHAR PathBuffer[1];
+		} SymbolicLinkReparseBuffer;
+		struct {
+			WORD   SubstituteNameOffset;
+			WORD   SubstituteNameLength;
+			WORD   PrintNameOffset;
+			WORD   PrintNameLength;
+			WCHAR PathBuffer[1];
+		} MountPointReparseBuffer;
+		struct {
+			BYTE   DataBuffer[1];
+		} GenericReparseBuffer;
+	} DUMMYUNIONNAME;
+} REPARSE_DATA_BUFFER, *PREPARSE_DATA_BUFFER;
+#endif
+
+int readlink(const char *path, char *buf, size_t bufsiz)
+{
+	HANDLE handle;
+	WCHAR wpath[MAX_LONG_PATH], *wbuf;
+	REPARSE_DATA_BUFFER *b = alloca(MAXIMUM_REPARSE_DATA_BUFFER_SIZE);
+	DWORD dummy;
+	char tmpbuf[MAX_LONG_PATH];
+	int len;
+
+	if (xutftowcs_long_path(wpath, path) < 0)
+		return -1;
+
+	/* read reparse point data */
+	handle = CreateFileW(wpath, 0,
+			FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
+			OPEN_EXISTING,
+			FILE_FLAG_BACKUP_SEMANTICS | FILE_FLAG_OPEN_REPARSE_POINT, NULL);
+	if (handle == INVALID_HANDLE_VALUE) {
+		errno = err_win_to_posix(GetLastError());
+		return -1;
+	}
+	if (!DeviceIoControl(handle, FSCTL_GET_REPARSE_POINT, NULL, 0, b,
+			MAXIMUM_REPARSE_DATA_BUFFER_SIZE, &dummy, NULL)) {
+		errno = err_win_to_posix(GetLastError());
+		CloseHandle(handle);
+		return -1;
+	}
+	CloseHandle(handle);
+
+	/* get target path for symlinks or mount points (aka 'junctions') */
+	switch (b->ReparseTag) {
+	case IO_REPARSE_TAG_SYMLINK:
+		wbuf = (WCHAR*) (((char*) b->SymbolicLinkReparseBuffer.PathBuffer)
+				+ b->SymbolicLinkReparseBuffer.SubstituteNameOffset);
+		*(WCHAR*) (((char*) wbuf)
+				+ b->SymbolicLinkReparseBuffer.SubstituteNameLength) = 0;
+		break;
+	case IO_REPARSE_TAG_MOUNT_POINT:
+		wbuf = (WCHAR*) (((char*) b->MountPointReparseBuffer.PathBuffer)
+				+ b->MountPointReparseBuffer.SubstituteNameOffset);
+		*(WCHAR*) (((char*) wbuf)
+				+ b->MountPointReparseBuffer.SubstituteNameLength) = 0;
+		break;
+	default:
+		errno = EINVAL;
+		return -1;
+	}
+
+	/*
+	 * Adapt to strange readlink() API: Copy up to bufsiz *bytes*, potentially
+	 * cutting off a UTF-8 sequence. Insufficient bufsize is *not* a failure
+	 * condition. There is no conversion function that produces invalid UTF-8,
+	 * so convert to a (hopefully large enough) temporary buffer, then memcpy
+	 * the requested number of bytes (including '\0' for robustness).
+	 */
+	if ((len = xwcstoutf(tmpbuf, normalize_ntpath(wbuf), MAX_LONG_PATH)) < 0)
+		return -1;
+	memcpy(buf, tmpbuf, min(bufsiz, len + 1));
+	return min(bufsiz, len);
+}
+
 pid_t waitpid(pid_t pid, int *status, int options)
 {
 	HANDLE h = OpenProcess(SYNCHRONIZE | PROCESS_QUERY_INFORMATION,
diff --git a/compat/mingw.h b/compat/mingw.h
index bc1d36b49d5a17..45d1615a9665d7 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -125,8 +125,6 @@ struct utsname {
  * trivial stubs
  */
 
-static inline int readlink(const char *path, char *buf, size_t bufsiz)
-{ errno = ENOSYS; return -1; }
 static inline int symlink(const char *oldpath, const char *newpath)
 { errno = ENOSYS; return -1; }
 static inline int fchmod(int fildes, mode_t mode)
@@ -222,6 +220,7 @@ int setitimer(int type, struct itimerval *in, struct itimerval *out);
 int sigaction(int sig, struct sigaction *in, struct sigaction *out);
 int link(const char *oldpath, const char *newpath);
 int uname(struct utsname *buf);
+int readlink(const char *path, char *buf, size_t bufsiz);
 
 /*
  * replacements of existing functions

From 7cbbc7e76764b5f83abb56e14205f4c6e926d1c5 Mon Sep 17 00:00:00 2001
From: Bill Zissimopoulos <billziss@navimatics.com>
Date: Thu, 28 May 2020 16:35:57 -0700
Subject: [PATCH 209/259] mingw: lstat: compute correct size for symlinks

This commit fixes mingw_lstat by computing the proper size for symlinks
according to POSIX. POSIX specifies that upon successful return from
lstat: "the value of the st_size member shall be set to the length of
the pathname contained in the symbolic link not including any
terminating null byte".

Prior to this commit the mingw_lstat function returned a fixed size of
4096. This caused problems in git repositories that were accessed by
git for Cygwin or git for WSL. For example, doing `git reset --hard`
using git for Windows would update the size of symlinks in the index
to be 4096; at a later time git for Cygwin or git for WSL would find
that symlinks have changed size during `git status`. Vice versa doing
`git reset --hard` in git for Cygwin or git for WSL would update the
size of symlinks in the index with the correct value, only for git for
Windows to find incorrectly at a later time that the size had changed.

Signed-off-by: Bill Zissimopoulos <billziss@navimatics.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c         | 65 ++++++++++++++++++++++++++++--------------
 compat/win32/fscache.c | 12 ++++++++
 2 files changed, 56 insertions(+), 21 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 530ef747032d23..f9012d9b726038 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -893,10 +893,14 @@ static int has_valid_directory_prefix(wchar_t *wfilename)
 	return 1;
 }
 
+static int readlink_1(const WCHAR *wpath, BOOL fail_on_unknown_tag,
+		      char *tmpbuf, int *plen, DWORD *ptag);
+
 int mingw_lstat(const char *file_name, struct stat *buf)
 {
 	WIN32_FILE_ATTRIBUTE_DATA fdata;
-	WIN32_FIND_DATAW findbuf = { 0 };
+	DWORD reparse_tag = 0;
+	int link_len = 0;
 	wchar_t wfilename[MAX_LONG_PATH];
 	int wlen = xutftowcs_long_path(wfilename, file_name);
 	if (wlen < 0)
@@ -911,20 +915,21 @@ int mingw_lstat(const char *file_name, struct stat *buf)
 	}
 
 	if (GetFileAttributesExW(wfilename, GetFileExInfoStandard, &fdata)) {
-		/* for reparse points, use FindFirstFile to get the reparse tag */
+		/* for reparse points, get the link tag and length */
 		if (fdata.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
-			HANDLE handle = FindFirstFileW(wfilename, &findbuf);
-			if (handle == INVALID_HANDLE_VALUE)
-				goto error;
-			FindClose(handle);
+			char tmpbuf[MAX_LONG_PATH];
+
+			if (readlink_1(wfilename, FALSE, tmpbuf, &link_len,
+				       &reparse_tag) < 0)
+				return -1;
 		}
 		buf->st_ino = 0;
 		buf->st_gid = 0;
 		buf->st_uid = 0;
 		buf->st_nlink = 1;
 		buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes,
-				findbuf.dwReserved0);
-		buf->st_size = S_ISLNK(buf->st_mode) ? MAX_LONG_PATH :
+				reparse_tag);
+		buf->st_size = S_ISLNK(buf->st_mode) ? link_len :
 			fdata.nFileSizeLow | (((off_t) fdata.nFileSizeHigh) << 32);
 		buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 		filetime_to_timespec(&(fdata.ftLastAccessTime), &(buf->st_atim));
@@ -932,7 +937,7 @@ int mingw_lstat(const char *file_name, struct stat *buf)
 		filetime_to_timespec(&(fdata.ftCreationTime), &(buf->st_ctim));
 		return 0;
 	}
-error:
+
 	switch (GetLastError()) {
 	case ERROR_ACCESS_DENIED:
 	case ERROR_SHARING_VIOLATION:
@@ -2789,17 +2794,13 @@ typedef struct _REPARSE_DATA_BUFFER {
 } REPARSE_DATA_BUFFER, *PREPARSE_DATA_BUFFER;
 #endif
 
-int readlink(const char *path, char *buf, size_t bufsiz)
+static int readlink_1(const WCHAR *wpath, BOOL fail_on_unknown_tag,
+		      char *tmpbuf, int *plen, DWORD *ptag)
 {
 	HANDLE handle;
-	WCHAR wpath[MAX_LONG_PATH], *wbuf;
+	WCHAR *wbuf;
 	REPARSE_DATA_BUFFER *b = alloca(MAXIMUM_REPARSE_DATA_BUFFER_SIZE);
 	DWORD dummy;
-	char tmpbuf[MAX_LONG_PATH];
-	int len;
-
-	if (xutftowcs_long_path(wpath, path) < 0)
-		return -1;
 
 	/* read reparse point data */
 	handle = CreateFileW(wpath, 0,
@@ -2819,7 +2820,7 @@ int readlink(const char *path, char *buf, size_t bufsiz)
 	CloseHandle(handle);
 
 	/* get target path for symlinks or mount points (aka 'junctions') */
-	switch (b->ReparseTag) {
+	switch ((*ptag = b->ReparseTag)) {
 	case IO_REPARSE_TAG_SYMLINK:
 		wbuf = (WCHAR*) (((char*) b->SymbolicLinkReparseBuffer.PathBuffer)
 				+ b->SymbolicLinkReparseBuffer.SubstituteNameOffset);
@@ -2833,10 +2834,34 @@ int readlink(const char *path, char *buf, size_t bufsiz)
 				+ b->MountPointReparseBuffer.SubstituteNameLength) = 0;
 		break;
 	default:
-		errno = EINVAL;
-		return -1;
+		if (fail_on_unknown_tag) {
+			errno = EINVAL;
+			return -1;
+		} else {
+			*plen = MAX_LONG_PATH;
+			return 0;
+		}
 	}
 
+	if ((*plen =
+	     xwcstoutf(tmpbuf, normalize_ntpath(wbuf), MAX_LONG_PATH)) <  0)
+		return -1;
+	return 0;
+}
+
+int readlink(const char *path, char *buf, size_t bufsiz)
+{
+	WCHAR wpath[MAX_LONG_PATH];
+	char tmpbuf[MAX_LONG_PATH];
+	int len;
+	DWORD tag;
+
+	if (xutftowcs_long_path(wpath, path) < 0)
+		return -1;
+
+	if (readlink_1(wpath, TRUE, tmpbuf, &len, &tag) < 0)
+		return -1;
+
 	/*
 	 * Adapt to strange readlink() API: Copy up to bufsiz *bytes*, potentially
 	 * cutting off a UTF-8 sequence. Insufficient bufsize is *not* a failure
@@ -2844,8 +2869,6 @@ int readlink(const char *path, char *buf, size_t bufsiz)
 	 * so convert to a (hopefully large enough) temporary buffer, then memcpy
 	 * the requested number of bytes (including '\0' for robustness).
 	 */
-	if ((len = xwcstoutf(tmpbuf, normalize_ntpath(wbuf), MAX_LONG_PATH)) < 0)
-		return -1;
 	memcpy(buf, tmpbuf, min(bufsiz, len + 1));
 	return min(bufsiz, len);
 }
diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index 3016ae61dee5e0..d3819aa7f86466 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -584,6 +584,18 @@ int fscache_lstat(const char *filename, struct stat *st)
 		return -1;
 	}
 
+	/*
+	 * Special case symbolic links: FindFirstFile()/FindNextFile() did not
+	 * provide us with the length of the target path.
+	 */
+	if (fse->u.s.st_size == MAX_LONG_PATH && S_ISLNK(fse->st_mode)) {
+		char buf[MAX_LONG_PATH];
+		int len = readlink(filename, buf, sizeof(buf) - 1);
+
+		if (len > 0)
+			fse->u.s.st_size = len;
+	}
+
 	/* copy stat data */
 	st->st_ino = 0;
 	st->st_gid = 0;

From d9676dc22cd266452dc200478bd47e6ff4e05d08 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sun, 24 May 2015 01:32:03 +0200
Subject: [PATCH 210/259] Win32: implement basic symlink() functionality (file
 symlinks only)

Implement symlink() that always creates file symlinks. Fails with ENOSYS
if symlinks are disabled or unsupported.

Note: CreateSymbolicLinkW() was introduced with symlink support in Windows
Vista. For compatibility with Windows XP, we need to load it dynamically
and fail gracefully if it isnt's available.

Signed-off-by: Karsten Blees <blees@dcon.de>
---
 compat/mingw.c | 28 ++++++++++++++++++++++++++++
 compat/mingw.h |  3 +--
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index f9012d9b726038..0ac2687beab38f 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2758,6 +2758,34 @@ int link(const char *oldpath, const char *newpath)
 	return 0;
 }
 
+int symlink(const char *target, const char *link)
+{
+	wchar_t wtarget[MAX_LONG_PATH], wlink[MAX_LONG_PATH];
+	int len;
+
+	/* fail if symlinks are disabled or API is not supported (WinXP) */
+	if (!has_symlinks) {
+		errno = ENOSYS;
+		return -1;
+	}
+
+	if ((len = xutftowcs_long_path(wtarget, target)) < 0
+			|| xutftowcs_long_path(wlink, link) < 0)
+		return -1;
+
+	/* convert target dir separators to backslashes */
+	while (len--)
+		if (wtarget[len] == '/')
+			wtarget[len] = '\\';
+
+	/* create file symlink */
+	if (!CreateSymbolicLinkW(wlink, wtarget, 0)) {
+		errno = err_win_to_posix(GetLastError());
+		return -1;
+	}
+	return 0;
+}
+
 #ifndef _WINNT_H
 /*
  * The REPARSE_DATA_BUFFER structure is defined in the Windows DDK (in
diff --git a/compat/mingw.h b/compat/mingw.h
index 45d1615a9665d7..a74024f8b060cd 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -125,8 +125,6 @@ struct utsname {
  * trivial stubs
  */
 
-static inline int symlink(const char *oldpath, const char *newpath)
-{ errno = ENOSYS; return -1; }
 static inline int fchmod(int fildes, mode_t mode)
 { errno = ENOSYS; return -1; }
 #ifndef __MINGW64_VERSION_MAJOR
@@ -220,6 +218,7 @@ int setitimer(int type, struct itimerval *in, struct itimerval *out);
 int sigaction(int sig, struct sigaction *in, struct sigaction *out);
 int link(const char *oldpath, const char *newpath);
 int uname(struct utsname *buf);
+int symlink(const char *target, const char *link);
 int readlink(const char *path, char *buf, size_t bufsiz);
 
 /*

From 3d785fc4259efab8aadb23aad8b4b627cca31f24 Mon Sep 17 00:00:00 2001
From: Karsten Blees <blees@dcon.de>
Date: Sun, 24 May 2015 01:48:35 +0200
Subject: [PATCH 211/259] Win32: symlink: add support for symlinks to
 directories

Symlinks on Windows have a flag that indicates whether the target is a file
or a directory. Symlinks of wrong type simply don't work. This even affects
core Win32 APIs (e.g. DeleteFile() refuses to delete directory symlinks).

However, CreateFile() with FILE_FLAG_BACKUP_SEMANTICS doesn't seem to care.
Check the target type by first creating a tentative file symlink, opening
it, and checking the type of the resulting handle. If it is a directory,
recreate the symlink with the directory flag set.

It is possible to create symlinks before the target exists (or in case of
symlinks to symlinks: before the target type is known). If this happens,
create a tentative file symlink and postpone the directory decision: keep
a list of phantom symlinks to be processed whenever a new directory is
created in mingw_mkdir().

Limitations: This algorithm may fail if a link target changes from file to
directory or vice versa, or if the target directory is created in another
process.

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 159 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 159 insertions(+)

diff --git a/compat/mingw.c b/compat/mingw.c
index 0ac2687beab38f..9f0bf4b3a058d9 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -335,6 +335,126 @@ static inline int is_wdir_sep(wchar_t wchar)
 	return wchar == L'/' || wchar == L'\\';
 }
 
+static const wchar_t *make_relative_to(const wchar_t *path,
+				       const wchar_t *relative_to, wchar_t *out,
+				       size_t size)
+{
+	size_t i = wcslen(relative_to), len;
+
+	/* Is `path` already absolute? */
+	if (is_wdir_sep(path[0]) ||
+	    (iswalpha(path[0]) && path[1] == L':' && is_wdir_sep(path[2])))
+		return path;
+
+	while (i > 0 && !is_wdir_sep(relative_to[i - 1]))
+		i--;
+
+	/* Is `relative_to` in the current directory? */
+	if (!i)
+		return path;
+
+	len = wcslen(path);
+	if (i + len + 1 > size) {
+		error("Could not make '%ls' relative to '%ls' (too large)",
+		      path, relative_to);
+		return NULL;
+	}
+
+	memcpy(out, relative_to, i * sizeof(wchar_t));
+	wcscpy(out + i, path);
+	return out;
+}
+
+enum phantom_symlink_result {
+	PHANTOM_SYMLINK_RETRY,
+	PHANTOM_SYMLINK_DONE,
+	PHANTOM_SYMLINK_DIRECTORY
+};
+
+/*
+ * Changes a file symlink to a directory symlink if the target exists and is a
+ * directory.
+ */
+static enum phantom_symlink_result
+process_phantom_symlink(const wchar_t *wtarget, const wchar_t *wlink)
+{
+	HANDLE hnd;
+	BY_HANDLE_FILE_INFORMATION fdata;
+	wchar_t relative[MAX_LONG_PATH];
+	const wchar_t *rel;
+
+	/* check that wlink is still a file symlink */
+	if ((GetFileAttributesW(wlink)
+			& (FILE_ATTRIBUTE_REPARSE_POINT | FILE_ATTRIBUTE_DIRECTORY))
+			!= FILE_ATTRIBUTE_REPARSE_POINT)
+		return PHANTOM_SYMLINK_DONE;
+
+	/* make it relative, if necessary */
+	rel = make_relative_to(wtarget, wlink, relative, ARRAY_SIZE(relative));
+	if (!rel)
+		return PHANTOM_SYMLINK_DONE;
+
+	/* let Windows resolve the link by opening it */
+	hnd = CreateFileW(rel, 0,
+			FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
+			OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+	if (hnd == INVALID_HANDLE_VALUE) {
+		errno = err_win_to_posix(GetLastError());
+		return PHANTOM_SYMLINK_RETRY;
+	}
+
+	if (!GetFileInformationByHandle(hnd, &fdata)) {
+		errno = err_win_to_posix(GetLastError());
+		CloseHandle(hnd);
+		return PHANTOM_SYMLINK_RETRY;
+	}
+	CloseHandle(hnd);
+
+	/* if target exists and is a file, we're done */
+	if (!(fdata.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY))
+		return PHANTOM_SYMLINK_DONE;
+
+	/* otherwise recreate the symlink with directory flag */
+	if (DeleteFileW(wlink) && CreateSymbolicLinkW(wlink, wtarget, 1))
+		return PHANTOM_SYMLINK_DIRECTORY;
+
+	errno = err_win_to_posix(GetLastError());
+	return PHANTOM_SYMLINK_RETRY;
+}
+
+/* keep track of newly created symlinks to non-existing targets */
+struct phantom_symlink_info {
+	struct phantom_symlink_info *next;
+	wchar_t *wlink;
+	wchar_t *wtarget;
+};
+
+static struct phantom_symlink_info *phantom_symlinks = NULL;
+static CRITICAL_SECTION phantom_symlinks_cs;
+
+static void process_phantom_symlinks(void)
+{
+	struct phantom_symlink_info *current, **psi;
+	EnterCriticalSection(&phantom_symlinks_cs);
+	/* process phantom symlinks list */
+	psi = &phantom_symlinks;
+	while ((current = *psi)) {
+		enum phantom_symlink_result result = process_phantom_symlink(
+				current->wtarget, current->wlink);
+		if (result == PHANTOM_SYMLINK_RETRY) {
+			psi = &current->next;
+		} else {
+			/* symlink was processed, remove from list */
+			*psi = current->next;
+			free(current);
+			/* if symlink was a directory, start over */
+			if (result == PHANTOM_SYMLINK_DIRECTORY)
+				psi = &phantom_symlinks;
+		}
+	}
+	LeaveCriticalSection(&phantom_symlinks_cs);
+}
+
 /* Normalizes NT paths as returned by some low-level APIs. */
 static wchar_t *normalize_ntpath(wchar_t *wbuf)
 {
@@ -518,6 +638,8 @@ int mingw_mkdir(const char *path, int mode)
 		return -1;
 
 	ret = _wmkdir(wpath);
+	if (!ret)
+		process_phantom_symlinks();
 	if (!ret && needs_hiding(path))
 		return set_hidden_flag(wpath, 1);
 	return ret;
@@ -2783,6 +2905,42 @@ int symlink(const char *target, const char *link)
 		errno = err_win_to_posix(GetLastError());
 		return -1;
 	}
+
+	/* convert to directory symlink if target exists */
+	switch (process_phantom_symlink(wtarget, wlink)) {
+	case PHANTOM_SYMLINK_RETRY:	{
+		/* if target doesn't exist, add to phantom symlinks list */
+		wchar_t wfullpath[MAX_LONG_PATH];
+		struct phantom_symlink_info *psi;
+
+		/* convert to absolute path to be independent of cwd */
+		len = GetFullPathNameW(wlink, MAX_LONG_PATH, wfullpath, NULL);
+		if (!len || len >= MAX_LONG_PATH) {
+			errno = err_win_to_posix(GetLastError());
+			return -1;
+		}
+
+		/* over-allocate and fill phantom_symlink_info structure */
+		psi = xmalloc(sizeof(struct phantom_symlink_info)
+			+ sizeof(wchar_t) * (len + wcslen(wtarget) + 2));
+		psi->wlink = (wchar_t *)(psi + 1);
+		wcscpy(psi->wlink, wfullpath);
+		psi->wtarget = psi->wlink + len + 1;
+		wcscpy(psi->wtarget, wtarget);
+
+		EnterCriticalSection(&phantom_symlinks_cs);
+		psi->next = phantom_symlinks;
+		phantom_symlinks = psi;
+		LeaveCriticalSection(&phantom_symlinks_cs);
+		break;
+	}
+	case PHANTOM_SYMLINK_DIRECTORY:
+		/* if we created a dir symlink, process other phantom symlinks */
+		process_phantom_symlinks();
+		break;
+	default:
+		break;
+	}
 	return 0;
 }
 
@@ -3743,6 +3901,7 @@ int wmain(int argc, const wchar_t **wargv)
 
 	/* initialize critical section for waitpid pinfo_t list */
 	InitializeCriticalSection(&pinfo_cs);
+	InitializeCriticalSection(&phantom_symlinks_cs);
 
 	/* initialize critical section for fscache */
 	InitializeCriticalSection(&fscache_cs);

From 410c9d4ee1247b62a31aac0287fffc3a2ec94b7b Mon Sep 17 00:00:00 2001
From: JiSeop Moon <zcube@zcube.kr>
Date: Mon, 23 Apr 2018 22:30:18 +0900
Subject: [PATCH 212/259] mingw: introduce code to detect whether we're inside
 a Windows container

This will come in handy in the next commit.

Signed-off-by: JiSeop Moon <zcube@zcube.kr>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 32 ++++++++++++++++++++++++++++++++
 compat/mingw.h |  5 +++++
 2 files changed, 37 insertions(+)

diff --git a/compat/mingw.c b/compat/mingw.c
index 4626f98e522058..fbbbe86f8e21c4 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -3996,3 +3996,35 @@ int mingw_have_unix_sockets(void)
 	return ret;
 }
 #endif
+
+/*
+ * Based on https://stackoverflow.com/questions/43002803
+ *
+ * [HKLM\SYSTEM\CurrentControlSet\Services\cexecsvc]
+ * "DisplayName"="@%systemroot%\\system32\\cexecsvc.exe,-100"
+ * "ErrorControl"=dword:00000001
+ * "ImagePath"=hex(2):25,00,73,00,79,00,73,00,74,00,65,00,6d,00,72,00,6f,00,
+ *    6f,00,74,00,25,00,5c,00,73,00,79,00,73,00,74,00,65,00,6d,00,33,00,32,00,
+ *    5c,00,63,00,65,00,78,00,65,00,63,00,73,00,76,00,63,00,2e,00,65,00,78,00,
+ *    65,00,00,00
+ * "Start"=dword:00000002
+ * "Type"=dword:00000010
+ * "Description"="@%systemroot%\\system32\\cexecsvc.exe,-101"
+ * "ObjectName"="LocalSystem"
+ * "ServiceSidType"=dword:00000001
+ */
+int is_inside_windows_container(void)
+{
+	static int inside_container = -1; /* -1 uninitialized */
+	const char *key = "SYSTEM\\CurrentControlSet\\Services\\cexecsvc";
+	HKEY handle = NULL;
+
+	if (inside_container != -1)
+		return inside_container;
+
+	inside_container = ERROR_SUCCESS ==
+		RegOpenKeyExA(HKEY_LOCAL_MACHINE, key, 0, KEY_READ, &handle);
+	RegCloseKey(handle);
+
+	return inside_container;
+}
diff --git a/compat/mingw.h b/compat/mingw.h
index a74024f8b060cd..f085a0806941ad 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -728,3 +728,8 @@ int mingw_have_unix_sockets(void);
 #undef have_unix_sockets
 #define have_unix_sockets mingw_have_unix_sockets
 #endif
+
+/*
+ * Check current process is inside Windows Container.
+ */
+int is_inside_windows_container(void);

From b9b2adca006a5c051b40888d945f3b9f47cf5e0c Mon Sep 17 00:00:00 2001
From: Bert Belder <bertbelder@gmail.com>
Date: Fri, 26 Oct 2018 11:13:45 +0200
Subject: [PATCH 213/259] Win32: symlink: move phantom symlink creation to a
 separate function

Signed-off-by: Bert Belder <bertbelder@gmail.com>
---
 compat/mingw.c | 91 +++++++++++++++++++++++++++-----------------------
 1 file changed, 49 insertions(+), 42 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 4626f98e522058..081cf9250c14df 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -458,6 +458,54 @@ static void process_phantom_symlinks(void)
 	LeaveCriticalSection(&phantom_symlinks_cs);
 }
 
+static int create_phantom_symlink(wchar_t *wtarget, wchar_t *wlink)
+{
+	int len;
+
+	/* create file symlink */
+	if (!CreateSymbolicLinkW(wlink, wtarget, symlink_file_flags)) {
+		errno = err_win_to_posix(GetLastError());
+		return -1;
+	}
+
+	/* convert to directory symlink if target exists */
+	switch (process_phantom_symlink(wtarget, wlink)) {
+	case PHANTOM_SYMLINK_RETRY: {
+		/* if target doesn't exist, add to phantom symlinks list */
+		wchar_t wfullpath[MAX_LONG_PATH];
+		struct phantom_symlink_info *psi;
+
+		/* convert to absolute path to be independent of cwd */
+		len = GetFullPathNameW(wlink, MAX_LONG_PATH, wfullpath, NULL);
+		if (!len || len >= MAX_LONG_PATH) {
+			errno = err_win_to_posix(GetLastError());
+			return -1;
+		}
+
+		/* over-allocate and fill phantom_symlink_info structure */
+		psi = xmalloc(sizeof(struct phantom_symlink_info) +
+			      sizeof(wchar_t) * (len + wcslen(wtarget) + 2));
+		psi->wlink = (wchar_t *)(psi + 1);
+		wcscpy(psi->wlink, wfullpath);
+		psi->wtarget = psi->wlink + len + 1;
+		wcscpy(psi->wtarget, wtarget);
+
+		EnterCriticalSection(&phantom_symlinks_cs);
+		psi->next = phantom_symlinks;
+		phantom_symlinks = psi;
+		LeaveCriticalSection(&phantom_symlinks_cs);
+		break;
+	}
+	case PHANTOM_SYMLINK_DIRECTORY:
+		/* if we created a dir symlink, process other phantom symlinks */
+		process_phantom_symlinks();
+		break;
+	default:
+		break;
+	}
+	return 0;
+}
+
 /* Normalizes NT paths as returned by some low-level APIs. */
 static wchar_t *normalize_ntpath(wchar_t *wbuf)
 {
@@ -2915,48 +2963,7 @@ int symlink(const char *target, const char *link)
 		if (wtarget[len] == '/')
 			wtarget[len] = '\\';
 
-	/* create file symlink */
-	if (!CreateSymbolicLinkW(wlink, wtarget, symlink_file_flags)) {
-		errno = err_win_to_posix(GetLastError());
-		return -1;
-	}
-
-	/* convert to directory symlink if target exists */
-	switch (process_phantom_symlink(wtarget, wlink)) {
-	case PHANTOM_SYMLINK_RETRY:	{
-		/* if target doesn't exist, add to phantom symlinks list */
-		wchar_t wfullpath[MAX_LONG_PATH];
-		struct phantom_symlink_info *psi;
-
-		/* convert to absolute path to be independent of cwd */
-		len = GetFullPathNameW(wlink, MAX_LONG_PATH, wfullpath, NULL);
-		if (!len || len >= MAX_LONG_PATH) {
-			errno = err_win_to_posix(GetLastError());
-			return -1;
-		}
-
-		/* over-allocate and fill phantom_symlink_info structure */
-		psi = xmalloc(sizeof(struct phantom_symlink_info)
-			+ sizeof(wchar_t) * (len + wcslen(wtarget) + 2));
-		psi->wlink = (wchar_t *)(psi + 1);
-		wcscpy(psi->wlink, wfullpath);
-		psi->wtarget = psi->wlink + len + 1;
-		wcscpy(psi->wtarget, wtarget);
-
-		EnterCriticalSection(&phantom_symlinks_cs);
-		psi->next = phantom_symlinks;
-		phantom_symlinks = psi;
-		LeaveCriticalSection(&phantom_symlinks_cs);
-		break;
-	}
-	case PHANTOM_SYMLINK_DIRECTORY:
-		/* if we created a dir symlink, process other phantom symlinks */
-		process_phantom_symlinks();
-		break;
-	default:
-		break;
-	}
-	return 0;
+	return create_phantom_symlink(wtarget, wlink);
 }
 
 #ifndef _WINNT_H

From db59bc42730adc9396edd4f430e7e2b128409c82 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 30 May 2017 21:50:57 +0200
Subject: [PATCH 214/259] mingw: try to create symlinks without elevated
 permissions

With Windows 10 Build 14972 in Developer Mode, a new flag is supported
by CreateSymbolicLink() to create symbolic links even when running
outside of an elevated session (which was previously required).

This new flag is called SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE and
has the numeric value 0x02.

Previous Windows 10 versions will not understand that flag and return an
ERROR_INVALID_PARAMETER, therefore we have to be careful to try passing
that flag only when the build number indicates that it is supported.

For more information about the new flag, see this blog post:
https://blogs.windows.com/buildingapps/2016/12/02/symlinks-windows-10/

This patch is loosely based on the patch submitted by Samuel D. Leslie
as https://github.com/git-for-windows/git/pull/1184.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 9f0bf4b3a058d9..0c39289654520c 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -365,6 +365,8 @@ static const wchar_t *make_relative_to(const wchar_t *path,
 	return out;
 }
 
+static DWORD symlink_file_flags = 0, symlink_directory_flags = 1;
+
 enum phantom_symlink_result {
 	PHANTOM_SYMLINK_RETRY,
 	PHANTOM_SYMLINK_DONE,
@@ -415,7 +417,8 @@ process_phantom_symlink(const wchar_t *wtarget, const wchar_t *wlink)
 		return PHANTOM_SYMLINK_DONE;
 
 	/* otherwise recreate the symlink with directory flag */
-	if (DeleteFileW(wlink) && CreateSymbolicLinkW(wlink, wtarget, 1))
+	if (DeleteFileW(wlink) &&
+	    CreateSymbolicLinkW(wlink, wtarget, symlink_directory_flags))
 		return PHANTOM_SYMLINK_DIRECTORY;
 
 	errno = err_win_to_posix(GetLastError());
@@ -2901,7 +2904,7 @@ int symlink(const char *target, const char *link)
 			wtarget[len] = '\\';
 
 	/* create file symlink */
-	if (!CreateSymbolicLinkW(wlink, wtarget, 0)) {
+	if (!CreateSymbolicLinkW(wlink, wtarget, symlink_file_flags)) {
 		errno = err_win_to_posix(GetLastError());
 		return -1;
 	}
@@ -3837,6 +3840,24 @@ static void maybe_redirect_std_handles(void)
 				  GENERIC_WRITE, FILE_FLAG_NO_BUFFERING);
 }
 
+static void adjust_symlink_flags(void)
+{
+	/*
+	 * Starting with Windows 10 Build 14972, symbolic links can be created
+	 * using CreateSymbolicLink() without elevation by passing the flag
+	 * SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE (0x02) as last
+	 * parameter, provided the Developer Mode has been enabled. Some
+	 * earlier Windows versions complain about this flag with an
+	 * ERROR_INVALID_PARAMETER, hence we have to test the build number
+	 * specifically.
+	 */
+	if (GetVersion() >= 14972 << 16) {
+		symlink_file_flags |= 2;
+		symlink_directory_flags |= 2;
+	}
+
+}
+
 #ifdef _MSC_VER
 #ifdef _DEBUG
 #include <crtdbg.h>
@@ -3871,6 +3892,7 @@ int wmain(int argc, const wchar_t **wargv)
 #endif
 
 	maybe_redirect_std_handles();
+	adjust_symlink_flags();
 	fsync_object_files = 1;
 
 	/* determine size of argv and environ conversion buffer */

From 0c61ae874965a7d95cf0a7c0118fbcd612f400a7 Mon Sep 17 00:00:00 2001
From: JiSeop Moon <zcube@zcube.kr>
Date: Mon, 23 Apr 2018 22:31:42 +0200
Subject: [PATCH 215/259] mingw: when running in a Windows container, try to
 rename() harder

It is a known issue that a rename() can fail with an "Access denied"
error at times, when copying followed by deleting the original file
works. Let's just fall back to that behavior.

Signed-off-by: JiSeop Moon <zcube@zcube.kr>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/compat/mingw.c b/compat/mingw.c
index fbbbe86f8e21c4..8df2e9740d7b42 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2590,6 +2590,13 @@ int mingw_rename(const char *pold, const char *pnew)
 		return 0;
 	gle = GetLastError();
 
+	if (gle == ERROR_ACCESS_DENIED && is_inside_windows_container()) {
+		/* Fall back to copy to destination & remove source */
+		if (CopyFileW(wpold, wpnew, FALSE) && !mingw_unlink(pold))
+			return 0;
+		gle = GetLastError();
+	}
+
 	/* revert file attributes on failure */
 	if (attrs != INVALID_FILE_ATTRIBUTES)
 		SetFileAttributesW(wpnew, attrs);

From 9e51a9a18586fa7a2cea5c6afbdb64201cf116dc Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 11 Feb 2019 14:19:18 +0100
Subject: [PATCH 216/259] Introduce helper to create symlinks that knows about
 index_state

On Windows, symbolic links actually have a type depending on the target:
it can be a file or a directory.

In certain circumstances, this poses problems, e.g. when a symbolic link
is supposed to point into a submodule that is not checked out, so there
is no way for Git to auto-detect the type.

To help with that, we will add support over the course of the next
commits to specify that symlink type via the Git attributes. This
requires an index_state, though, something that Git for Windows'
`symlink()` replacement cannot know about because the function signature
is defined by the POSIX standard and not ours to change.

So let's introduce a helper function to create symbolic links that
*does* know about the index_state.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 apply.c              | 2 +-
 builtin/difftool.c   | 2 +-
 compat/mingw.c       | 2 +-
 compat/mingw.h       | 4 +++-
 entry.c              | 2 +-
 git-compat-util.h    | 9 +++++++++
 merge-recursive.c    | 2 +-
 refs/files-backend.c | 2 +-
 setup.c              | 4 ++--
 9 files changed, 20 insertions(+), 9 deletions(-)

diff --git a/apply.c b/apply.c
index 6e1060a952c317..d2a34abafe480e 100644
--- a/apply.c
+++ b/apply.c
@@ -4440,7 +4440,7 @@ static int try_create_file(struct apply_state *state, const char *path,
 		/* Although buf:size is counted string, it also is NUL
 		 * terminated.
 		 */
-		return !!symlink(buf, path);
+		return !!create_symlink(state && state->repo ? state->repo->index : NULL, buf, path);
 
 	fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
 	if (fd < 0)
diff --git a/builtin/difftool.c b/builtin/difftool.c
index dcc68e190c25b4..5cca20276a06c2 100644
--- a/builtin/difftool.c
+++ b/builtin/difftool.c
@@ -523,7 +523,7 @@ static int run_dir_diff(const char *extcmd, int symlinks, const char *prefix,
 				}
 				add_path(&wtdir, wtdir_len, dst_path);
 				if (symlinks) {
-					if (symlink(wtdir.buf, rdir.buf)) {
+					if (create_symlink(lstate.istate, wtdir.buf, rdir.buf)) {
 						ret = error_errno("could not symlink '%s' to '%s'", wtdir.buf, rdir.buf);
 						goto finish;
 					}
diff --git a/compat/mingw.c b/compat/mingw.c
index 081cf9250c14df..51821d5311f149 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2943,7 +2943,7 @@ int link(const char *oldpath, const char *newpath)
 	return 0;
 }
 
-int symlink(const char *target, const char *link)
+int mingw_create_symlink(struct index_state *index, const char *target, const char *link)
 {
 	wchar_t wtarget[MAX_LONG_PATH], wlink[MAX_LONG_PATH];
 	int len;
diff --git a/compat/mingw.h b/compat/mingw.h
index a74024f8b060cd..151f26674d185d 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h
@@ -218,8 +218,10 @@ int setitimer(int type, struct itimerval *in, struct itimerval *out);
 int sigaction(int sig, struct sigaction *in, struct sigaction *out);
 int link(const char *oldpath, const char *newpath);
 int uname(struct utsname *buf);
-int symlink(const char *target, const char *link);
 int readlink(const char *path, char *buf, size_t bufsiz);
+struct index_state;
+int mingw_create_symlink(struct index_state *index, const char *target, const char *link);
+#define create_symlink mingw_create_symlink
 
 /*
  * replacements of existing functions
diff --git a/entry.c b/entry.c
index 75fdd39ff7db40..2f92fdb2fe069e 100644
--- a/entry.c
+++ b/entry.c
@@ -320,7 +320,7 @@ static int write_entry(struct cache_entry *ce, char *path, struct conv_attrs *ca
 		if (!has_symlinks || to_tempfile)
 			goto write_file_entry;
 
-		ret = symlink(new_blob, path);
+		ret = create_symlink(state->istate, new_blob, path);
 		free(new_blob);
 		if (ret)
 			return error_errno("unable to create symlink %s", path);
diff --git a/git-compat-util.h b/git-compat-util.h
index c9b4513c124b5a..53347307ad533a 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -627,6 +627,15 @@ static inline int git_has_dir_sep(const char *path)
 #define is_mount_point is_mount_point_via_stat
 #endif
 
+#ifndef create_symlink
+struct index_state;
+static inline int git_create_symlink(struct index_state *index, const char *target, const char *link)
+{
+	return symlink(target, link);
+}
+#define create_symlink git_create_symlink
+#endif
+
 #ifndef query_user_email
 #define query_user_email() NULL
 #endif
diff --git a/merge-recursive.c b/merge-recursive.c
index 5cc638066af599..f606324dee3bdc 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -1004,7 +1004,7 @@ static int update_file_flags(struct merge_options *opt,
 			char *lnk = xmemdupz(buf, size);
 			safe_create_leading_directories_const(path);
 			unlink(path);
-			if (symlink(lnk, path))
+			if (create_symlink(&opt->priv->orig_index, lnk, path))
 				ret = err(opt, _("failed to symlink '%s': %s"),
 					  path, strerror(errno));
 			free(lnk);
diff --git a/refs/files-backend.c b/refs/files-backend.c
index 11551de8f84554..e2fdf8a1eb8a3e 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -1942,7 +1942,7 @@ static int create_ref_symlink(struct ref_lock *lock, const char *target)
 #ifndef NO_SYMLINK_HEAD
 	char *ref_path = get_locked_file_path(&lock->lk);
 	unlink(ref_path);
-	ret = symlink(target, ref_path);
+	ret = create_symlink(NULL, target, ref_path);
 	free(ref_path);
 
 	if (ret)
diff --git a/setup.c b/setup.c
index 2b44421660c1af..bd303e5de6b01f 100644
--- a/setup.c
+++ b/setup.c
@@ -2021,7 +2021,7 @@ static void copy_templates_1(struct strbuf *path, struct strbuf *template_path,
 			if (strbuf_readlink(&lnk, template_path->buf,
 					    st_template.st_size) < 0)
 				die_errno(_("cannot readlink '%s'"), template_path->buf);
-			if (symlink(lnk.buf, path->buf))
+			if (create_symlink(NULL, lnk.buf, path->buf))
 				die_errno(_("cannot symlink '%s' '%s'"),
 					  lnk.buf, path->buf);
 			strbuf_release(&lnk);
@@ -2268,7 +2268,7 @@ static int create_default_files(const char *template_path,
 		path = git_path_buf(&buf, "tXXXXXX");
 		if (!close(xmkstemp(path)) &&
 		    !unlink(path) &&
-		    !symlink("testing", path) &&
+		    !create_symlink(NULL, "testing", path) &&
 		    !lstat(path, &st1) &&
 		    S_ISLNK(st1.st_mode))
 			unlink(path); /* good */

From 1ebcc9984ea8df7985a6d995d19f0cc0d8395203 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 2 Mar 2020 21:54:29 +0100
Subject: [PATCH 217/259] mingw: emulate stat() a little more faithfully

When creating directories via `safe_create_leading_directories()`, we
might encounter an already-existing directory which is not
readable by the current user. To handle that situation, Git's code calls
`stat()` to determine whether we're looking at a directory.

In such a case, `CreateFile()` will fail, though, no matter what, and
consequently `mingw_stat()` will fail, too. But POSIX semantics seem to
still allow `stat()` to go forward.

So let's call `mingw_lstat()` for the rescue if we fail to get a file
handle due to denied permission in `mingw_stat()`, and fill the stat
info that way.

We need to be careful to not allow this to go forward in case that we're
looking at a symbolic link: to resolve the link, we would still have to
create a file handle, and we just found out that we cannot. Therefore,
`stat()` still needs to fail with `EACCES` in that case.

This fixes https://github.com/git-for-windows/git/issues/2531.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 0c39289654520c..4626f98e522058 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1127,7 +1127,19 @@ int mingw_stat(const char *file_name, struct stat *buf)
 			FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
 			OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
 	if (hnd == INVALID_HANDLE_VALUE) {
-		errno = err_win_to_posix(GetLastError());
+		DWORD err = GetLastError();
+
+		if (err == ERROR_ACCESS_DENIED &&
+		    !mingw_lstat(file_name, buf) &&
+		    !S_ISLNK(buf->st_mode))
+			/*
+			 * POSIX semantics state to still try to fill
+			 * information, even if permission is denied to create
+			 * a file handle.
+			 */
+			return 0;
+
+		errno = err_win_to_posix(err);
 		return -1;
 	}
 	result = get_file_info_by_handle(hnd, buf);

From c394cccaf93b7750d418530e9e9ec3edc091e134 Mon Sep 17 00:00:00 2001
From: JiSeop Moon <zcube@zcube.kr>
Date: Mon, 23 Apr 2018 22:35:26 +0200
Subject: [PATCH 218/259] mingw: move the file_attr_to_st_mode() function
 definition

In preparation for making this function a bit more complicated (to allow
for special-casing the `ContainerMappedDirectories` in Windows
containers, which look like a symbolic link, but are not), let's move it
out of the header.

Signed-off-by: JiSeop Moon <zcube@zcube.kr>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 14 ++++++++++++++
 compat/win32.h | 14 +-------------
 2 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 8df2e9740d7b42..2a1bba67560225 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -4035,3 +4035,17 @@ int is_inside_windows_container(void)
 
 	return inside_container;
 }
+
+int file_attr_to_st_mode (DWORD attr, DWORD tag)
+{
+	int fMode = S_IREAD;
+	if ((attr & FILE_ATTRIBUTE_REPARSE_POINT) && tag == IO_REPARSE_TAG_SYMLINK)
+		fMode |= S_IFLNK;
+	else if (attr & FILE_ATTRIBUTE_DIRECTORY)
+		fMode |= S_IFDIR;
+	else
+		fMode |= S_IFREG;
+	if (!(attr & FILE_ATTRIBUTE_READONLY))
+		fMode |= S_IWRITE;
+	return fMode;
+}
diff --git a/compat/win32.h b/compat/win32.h
index 671bcc81f93351..52169ae19f4371 100644
--- a/compat/win32.h
+++ b/compat/win32.h
@@ -6,19 +6,7 @@
 #include <windows.h>
 #endif
 
-static inline int file_attr_to_st_mode (DWORD attr, DWORD tag)
-{
-	int fMode = S_IREAD;
-	if ((attr & FILE_ATTRIBUTE_REPARSE_POINT) && tag == IO_REPARSE_TAG_SYMLINK)
-		fMode |= S_IFLNK;
-	else if (attr & FILE_ATTRIBUTE_DIRECTORY)
-		fMode |= S_IFDIR;
-	else
-		fMode |= S_IFREG;
-	if (!(attr & FILE_ATTRIBUTE_READONLY))
-		fMode |= S_IWRITE;
-	return fMode;
-}
+extern int file_attr_to_st_mode (DWORD attr, DWORD tag);
 
 static inline int get_file_attr(const char *fname, WIN32_FILE_ATTRIBUTE_DATA *fdata)
 {

From 38f7ed5f274b4392d1bd940a1d233205f8c3c151 Mon Sep 17 00:00:00 2001
From: Bert Belder <bertbelder@gmail.com>
Date: Fri, 26 Oct 2018 11:51:51 +0200
Subject: [PATCH 219/259] mingw: allow to specify the symlink type in
 .gitattributes

On Windows, symbolic links have a type: a "file symlink" must point at
a file, and a "directory symlink" must point at a directory. If the
type of symlink does not match its target, it doesn't work.

Git does not record the type of symlink in the index or in a tree. On
checkout it'll guess the type, which only works if the target exists
at the time the symlink is created. This may often not be the case,
for example when the link points at a directory inside a submodule.

By specifying `symlink=file` or `symlink=dir` the user can specify what
type of symlink Git should create, so Git doesn't have to rely on
unreliable heuristics.

Signed-off-by: Bert Belder <bertbelder@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 Documentation/gitattributes.txt | 30 +++++++++++++++++
 compat/mingw.c                  | 58 ++++++++++++++++++++++++++++++++-
 2 files changed, 87 insertions(+), 1 deletion(-)

diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index e6150595af8210..f2c07fa1b72be7 100644
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@ -403,6 +403,36 @@ sign `$` upon checkout.  Any byte sequence that begins with
 with `$Id$` upon check-in.
 
 
+`symlink`
+^^^^^^^^^
+
+On Windows, symbolic links have a type: a "file symlink" must point at
+a file, and a "directory symlink" must point at a directory. If the
+type of symlink does not match its target, it doesn't work.
+
+Git does not record the type of symlink in the index or in a tree. On
+checkout it'll guess the type, which only works if the target exists
+at the time the symlink is created. This may often not be the case,
+for example when the link points at a directory inside a submodule.
+
+The `symlink` attribute allows you to explicitly set the type of symlink
+to `file` or `dir`, so Git doesn't have to guess. If you have a set of
+symlinks that point at other files, you can do:
+
+------------------------
+*.gif 	symlink=file
+------------------------
+
+To tell Git that a symlink points at a directory, use:
+
+------------------------
+tools_folder 	symlink=dir
+------------------------
+
+The `symlink` attribute is ignored on platforms other than Windows,
+since they don't distinguish between different types of symlinks.
+
+
 `filter`
 ^^^^^^^^
 
diff --git a/compat/mingw.c b/compat/mingw.c
index 51821d5311f149..6b3b62333ec13e 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -23,6 +23,7 @@
 #include "../write-or-die.h"
 #include "../repository.h"
 #include "win32/fscache.h"
+#include "../attr.h"
 
 #define HCAST(type, handle) ((type)(intptr_t)handle)
 
@@ -2943,6 +2944,37 @@ int link(const char *oldpath, const char *newpath)
 	return 0;
 }
 
+enum symlink_type {
+	SYMLINK_TYPE_UNSPECIFIED = 0,
+	SYMLINK_TYPE_FILE,
+	SYMLINK_TYPE_DIRECTORY,
+};
+
+static enum symlink_type check_symlink_attr(struct index_state *index, const char *link)
+{
+	static struct attr_check *check;
+	const char *value;
+
+	if (!index)
+		return SYMLINK_TYPE_UNSPECIFIED;
+
+	if (!check)
+		check = attr_check_initl("symlink", NULL);
+
+	git_check_attr(index, link, check);
+
+	value = check->items[0].value;
+	if (ATTR_UNSET(value))
+		return SYMLINK_TYPE_UNSPECIFIED;
+	if (!strcmp(value, "file"))
+		return SYMLINK_TYPE_FILE;
+	if (!strcmp(value, "dir") || !strcmp(value, "directory"))
+		return SYMLINK_TYPE_DIRECTORY;
+
+	warning(_("ignoring invalid symlink type '%s' for '%s'"), value, link);
+	return SYMLINK_TYPE_UNSPECIFIED;
+}
+
 int mingw_create_symlink(struct index_state *index, const char *target, const char *link)
 {
 	wchar_t wtarget[MAX_LONG_PATH], wlink[MAX_LONG_PATH];
@@ -2963,7 +2995,31 @@ int mingw_create_symlink(struct index_state *index, const char *target, const ch
 		if (wtarget[len] == '/')
 			wtarget[len] = '\\';
 
-	return create_phantom_symlink(wtarget, wlink);
+	switch (check_symlink_attr(index, link)) {
+	case SYMLINK_TYPE_UNSPECIFIED:
+		/* Create a phantom symlink: it is initially created as a file
+		 * symlink, but may change to a directory symlink later if/when
+		 * the target exists. */
+		return create_phantom_symlink(wtarget, wlink);
+	case SYMLINK_TYPE_FILE:
+		if (!CreateSymbolicLinkW(wlink, wtarget, symlink_file_flags))
+			break;
+		return 0;
+	case SYMLINK_TYPE_DIRECTORY:
+		if (!CreateSymbolicLinkW(wlink, wtarget,
+					 symlink_directory_flags))
+			break;
+		/* There may be dangling phantom symlinks that point at this
+		 * one, which should now morph into directory symlinks. */
+		process_phantom_symlinks();
+		return 0;
+	default:
+		BUG("unhandled symlink type");
+	}
+
+	/* CreateSymbolicLinkW failed. */
+	errno = err_win_to_posix(GetLastError());
+	return -1;
 }
 
 #ifndef _WINNT_H

From dc6fbc78c21bef4351690d0e9c41f2144ae8099a Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 4 Jun 2020 23:16:07 +0200
Subject: [PATCH 220/259] mingw: special-case index entries for symlinks with
 buggy size

In https://github.com/git-for-windows/git/pull/2637, we fixed a bug
where symbolic links' target path sizes were recorded incorrectly in the
index. The downside of this fix was that every user with tracked
symbolic links in their checkouts would see them as modified in `git
status`, but not in `git diff`, and only a `git add <path>` (or `git add
-u`) would "fix" this.

Let's do better than that: we can detect that situation and simply
pretend that a symbolic link with a known bad size (or a size that just
happens to be that bad size, a _very_ unlikely scenario because it would
overflow our buffers due to the trailing NUL byte) means that it needs
to be re-checked as if we had just checked it out.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 read-cache.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/read-cache.c b/read-cache.c
index 33ae3c30b68728..4699180724c0f2 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -469,6 +469,17 @@ int ie_modified(struct index_state *istate,
 	 * then we know it is.
 	 */
 	if ((changed & DATA_CHANGED) &&
+#ifdef GIT_WINDOWS_NATIVE
+	    /*
+	     * Work around Git for Windows v2.27.0 fixing a bug where symlinks'
+	     * target path lengths were not read at all, and instead recorded
+	     * as 4096: now, all symlinks would appear as modified.
+	     *
+	     * So let's just special-case symlinks with a target path length
+	     * (i.e. `sd_size`) of 4096 and force them to be re-checked.
+	     */
+	    (!S_ISLNK(st->st_mode) || ce->ce_stat_data.sd_size != MAX_LONG_PATH) &&
+#endif
 	    (S_ISGITLINK(ce->ce_mode) || ce->ce_stat_data.sd_size != 0))
 		return changed;
 

From 722a834d5bb0713c3632882f682c34a420609028 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 23 Apr 2018 23:20:00 +0200
Subject: [PATCH 221/259] mingw: Windows Docker volumes are *not* symbolic
 links

... even if they may look like them.

As looking up the target of the "symbolic link" (just to see whether it
starts with `/ContainerMappedDirectories/`) is pretty expensive, we
do it when we can be *really* sure that there is a possibility that this
might be the case.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: JiSeop Moon <zcube@zcube.kr>
---
 compat/mingw.c         | 25 +++++++++++++++++++------
 compat/win32.h         |  2 +-
 compat/win32/fscache.c | 24 +++++++++++++++++++++++-
 3 files changed, 43 insertions(+), 8 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 2a1bba67560225..765e5824552f5d 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1053,7 +1053,7 @@ int mingw_lstat(const char *file_name, struct stat *buf)
 		buf->st_uid = 0;
 		buf->st_nlink = 1;
 		buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes,
-				reparse_tag);
+				reparse_tag, file_name);
 		buf->st_size = S_ISLNK(buf->st_mode) ? link_len :
 			fdata.nFileSizeLow | (((off_t) fdata.nFileSizeHigh) << 32);
 		buf->st_dev = buf->st_rdev = 0; /* not used by Git */
@@ -1104,7 +1104,7 @@ static int get_file_info_by_handle(HANDLE hnd, struct stat *buf)
 	buf->st_gid = 0;
 	buf->st_uid = 0;
 	buf->st_nlink = 1;
-	buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes, 0);
+	buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes, 0, NULL);
 	buf->st_size = fdata.nFileSizeLow |
 		(((off_t)fdata.nFileSizeHigh)<<32);
 	buf->st_dev = buf->st_rdev = 0; /* not used by Git */
@@ -4036,12 +4036,25 @@ int is_inside_windows_container(void)
 	return inside_container;
 }
 
-int file_attr_to_st_mode (DWORD attr, DWORD tag)
+int file_attr_to_st_mode (DWORD attr, DWORD tag, const char *path)
 {
 	int fMode = S_IREAD;
-	if ((attr & FILE_ATTRIBUTE_REPARSE_POINT) && tag == IO_REPARSE_TAG_SYMLINK)
-		fMode |= S_IFLNK;
-	else if (attr & FILE_ATTRIBUTE_DIRECTORY)
+	if ((attr & FILE_ATTRIBUTE_REPARSE_POINT) &&
+	    tag == IO_REPARSE_TAG_SYMLINK) {
+		int flag = S_IFLNK;
+		char buf[MAX_LONG_PATH];
+
+		/*
+		 * Windows containers' mapped volumes are marked as reparse
+		 * points and look like symbolic links, but they are not.
+		 */
+		if (path && is_inside_windows_container() &&
+		    readlink(path, buf, sizeof(buf)) > 27 &&
+		    starts_with(buf, "/ContainerMappedDirectories/"))
+			flag = S_IFDIR;
+
+		fMode |= flag;
+	} else if (attr & FILE_ATTRIBUTE_DIRECTORY)
 		fMode |= S_IFDIR;
 	else
 		fMode |= S_IFREG;
diff --git a/compat/win32.h b/compat/win32.h
index 52169ae19f4371..299f01bdf0f5a4 100644
--- a/compat/win32.h
+++ b/compat/win32.h
@@ -6,7 +6,7 @@
 #include <windows.h>
 #endif
 
-extern int file_attr_to_st_mode (DWORD attr, DWORD tag);
+extern int file_attr_to_st_mode (DWORD attr, DWORD tag, const char *path);
 
 static inline int get_file_attr(const char *fname, WIN32_FILE_ATTRIBUTE_DATA *fdata)
 {
diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index d3819aa7f86466..e2a6fe272f5740 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -202,8 +202,30 @@ static struct fsentry *fseentry_create_entry(struct fscache *cache,
 		fdata->FileAttributes & FILE_ATTRIBUTE_REPARSE_POINT ?
 		fdata->EaSize : 0;
 
+	/*
+	 * On certain Windows versions, host directories mapped into
+	 * Windows Containers ("Volumes", see https://docs.docker.com/storage/volumes/)
+	 * look like symbolic links, but their targets are paths that
+	 * are valid only in kernel mode.
+	 *
+	 * Let's work around this by detecting that situation and
+	 * telling Git that these are *not* symbolic links.
+	 */
+	if (fse->reparse_tag == IO_REPARSE_TAG_SYMLINK &&
+	    sizeof(buf) > (list ? list->len + 1 : 0) + fse->len + 1 &&
+	    is_inside_windows_container()) {
+		size_t off = 0;
+		if (list) {
+			memcpy(buf, list->dirent.d_name, list->len);
+			buf[list->len] = '/';
+			off = list->len + 1;
+		}
+		memcpy(buf + off, fse->dirent.d_name, fse->len);
+		buf[off + fse->len] = '\0';
+	}
+
 	fse->st_mode = file_attr_to_st_mode(fdata->FileAttributes,
-					    fdata->EaSize);
+					    fdata->EaSize, buf);
 	fse->dirent.d_type = S_ISREG(fse->st_mode) ? DT_REG :
 			S_ISDIR(fse->st_mode) ? DT_DIR : DT_LNK;
 	fse->u.s.st_size = S_ISLNK(fse->st_mode) ? MAX_LONG_PATH :

From fba86f6a5070b73fa87489954134d2f8b51b1450 Mon Sep 17 00:00:00 2001
From: David Lomas <dl3@pale-eds.co.uk>
Date: Fri, 28 Jul 2023 15:20:43 +0100
Subject: [PATCH 222/259] mingw: work around rename() failing on a read-only
 file

At least on _some_ APFS network shares, Git fails to rename the object
files because they are marked as read-only, because that has the effect
of setting the uchg flag on APFS, which then means the file can't be
renamed or deleted.

To work around that, when a rename failed, and the read-only flag is
set, try to turn it off and on again.

This fixes https://github.com/git-for-windows/git/issues/4482

Signed-off-by: David Lomas <dl3@pale-eds.co.uk>
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
---
 compat/mingw.c | 25 +++++++++++++++++++------
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 765e5824552f5d..45e99182014299 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -2577,7 +2577,7 @@ int mingw_accept(int sockfd1, struct sockaddr *sa, socklen_t *sz)
 #undef rename
 int mingw_rename(const char *pold, const char *pnew)
 {
-	DWORD attrs = INVALID_FILE_ATTRIBUTES, gle;
+	DWORD attrs = INVALID_FILE_ATTRIBUTES, gle, attrsold;
 	int tries = 0;
 	wchar_t wpold[MAX_LONG_PATH], wpnew[MAX_LONG_PATH];
 	if (xutftowcs_long_path(wpold, pold) < 0 ||
@@ -2590,11 +2590,24 @@ int mingw_rename(const char *pold, const char *pnew)
 		return 0;
 	gle = GetLastError();
 
-	if (gle == ERROR_ACCESS_DENIED && is_inside_windows_container()) {
-		/* Fall back to copy to destination & remove source */
-		if (CopyFileW(wpold, wpnew, FALSE) && !mingw_unlink(pold))
-			return 0;
-		gle = GetLastError();
+	if (gle == ERROR_ACCESS_DENIED) {
+		if (is_inside_windows_container()) {
+			/* Fall back to copy to destination & remove source */
+			if (CopyFileW(wpold, wpnew, FALSE) && !mingw_unlink(pold))
+				return 0;
+			gle = GetLastError();
+		} else if ((attrsold = GetFileAttributesW(wpold)) & FILE_ATTRIBUTE_READONLY) {
+			/* if file is read-only, change and retry */
+			SetFileAttributesW(wpold, attrsold & ~FILE_ATTRIBUTE_READONLY);
+			if (MoveFileExW(wpold, wpnew,
+					MOVEFILE_REPLACE_EXISTING | MOVEFILE_COPY_ALLOWED)) {
+				SetFileAttributesW(wpnew, attrsold);
+				return 0;
+			}
+			gle = GetLastError();
+			/* revert attribute change on failure */
+			SetFileAttributesW(wpold, attrsold);
+		}
 	}
 
 	/* revert file attributes on failure */

From bda809db5d0fd82dfcfb41032765e458c350eae3 Mon Sep 17 00:00:00 2001
From: Bert Belder <bertbelder@gmail.com>
Date: Fri, 26 Oct 2018 23:42:09 +0200
Subject: [PATCH 223/259] Win32: symlink: add test for `symlink` attribute

To verify that the symlink is resolved correctly, we use the fact that
`git.exe` is a native Win32 program, and that `git.exe config -f <path>`
therefore uses the native symlink resolution.

Signed-off-by: Bert Belder <bertbelder@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t2040-checkout-symlink-attr.sh | 46 ++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)
 create mode 100755 t/t2040-checkout-symlink-attr.sh

diff --git a/t/t2040-checkout-symlink-attr.sh b/t/t2040-checkout-symlink-attr.sh
new file mode 100755
index 00000000000000..e00c31d096ce88
--- /dev/null
+++ b/t/t2040-checkout-symlink-attr.sh
@@ -0,0 +1,46 @@
+#!/bin/sh
+
+test_description='checkout symlinks with `symlink` attribute on Windows
+
+Ensures that Git for Windows creates symlinks of the right type,
+as specified by the `symlink` attribute in `.gitattributes`.'
+
+# Tell MSYS to create native symlinks. Without this flag test-lib's
+# prerequisite detection for SYMLINKS doesn't detect the right thing.
+MSYS=winsymlinks:nativestrict && export MSYS
+
+. ./test-lib.sh
+
+if ! test_have_prereq MINGW,SYMLINKS
+then
+	skip_all='skipping $0: MinGW-only test, which requires symlink support.'
+	test_done
+fi
+
+# Adds a symlink to the index without clobbering the work tree.
+cache_symlink () {
+	sha=$(printf '%s' "$1" | git hash-object --stdin -w) &&
+	git update-index --add --cacheinfo 120000,$sha,"$2"
+}
+
+test_expect_success 'checkout symlinks with attr' '
+	cache_symlink file1 file-link &&
+	cache_symlink dir dir-link &&
+
+	printf "file-link symlink=file\ndir-link symlink=dir\n" >.gitattributes &&
+	git add .gitattributes &&
+
+	git checkout . &&
+
+	mkdir dir &&
+	echo "[a]b=c" >file1 &&
+	echo "[x]y=z" >dir/file2 &&
+
+	# MSYS2 is very forgiving, it will resolve symlinks even if the
+	# symlink type is incorrect. To make this test meaningful, try
+	# them with a native, non-MSYS executable, such as `git config`.
+	test "$(git config -f file-link a.b)" = "c" &&
+	test "$(git config -f dir-link/file2 x.y)" = "z"
+'
+
+test_done

From 850e3caed6b6507a1f291874629ea5b46c364411 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 20 Jul 2017 22:45:01 +0200
Subject: [PATCH 224/259] mingw: explicitly specify with which cmd to prefix
 the cmdline

The main idea of this patch is that even if we have to look up the
absolute path of the script, if only the basename was specified as
argv[0], then we should use that basename on the command line, too, not
the absolute path.

This patch will also help with the upcoming patch where we automatically
substitute "sh ..." by "busybox sh ..." if "sh" is not in the PATH but
"busybox" is: we will do that by substituting the actual executable, but
still keep prepending "sh" to the command line.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 6b3b62333ec13e..4c964d38280b2e 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1896,8 +1896,8 @@ static int is_msys2_sh(const char *cmd)
 }
 
 static pid_t mingw_spawnve_fd(const char *cmd, const char **argv, char **deltaenv,
-			      const char *dir,
-			      int prepend_cmd, int fhin, int fhout, int fherr)
+			      const char *dir, const char *prepend_cmd,
+			      int fhin, int fhout, int fherr)
 {
 	static int restrict_handle_inheritance = -1;
 	STARTUPINFOEXW si;
@@ -1988,9 +1988,9 @@ static pid_t mingw_spawnve_fd(const char *cmd, const char **argv, char **deltaen
 	/* concatenate argv, quoting args as we go */
 	strbuf_init(&args, 0);
 	if (prepend_cmd) {
-		char *quoted = (char *)quote_arg(cmd);
+		char *quoted = (char *)quote_arg(prepend_cmd);
 		strbuf_addstr(&args, quoted);
-		if (quoted != cmd)
+		if (quoted != prepend_cmd)
 			free(quoted);
 	}
 	for (; *argv; argv++) {
@@ -2149,7 +2149,8 @@ static pid_t mingw_spawnve_fd(const char *cmd, const char **argv, char **deltaen
 	return (pid_t)pi.dwProcessId;
 }
 
-static pid_t mingw_spawnv(const char *cmd, const char **argv, int prepend_cmd)
+static pid_t mingw_spawnv(const char *cmd, const char **argv,
+			  const char *prepend_cmd)
 {
 	return mingw_spawnve_fd(cmd, argv, NULL, NULL, prepend_cmd, 0, 1, 2);
 }
@@ -2177,14 +2178,14 @@ pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **deltaenv,
 				pid = -1;
 			}
 			else {
-				pid = mingw_spawnve_fd(iprog, argv, deltaenv, dir, 1,
+				pid = mingw_spawnve_fd(iprog, argv, deltaenv, dir, interpr,
 						       fhin, fhout, fherr);
 				free(iprog);
 			}
 			argv[0] = argv0;
 		}
 		else
-			pid = mingw_spawnve_fd(prog, argv, deltaenv, dir, 0,
+			pid = mingw_spawnve_fd(prog, argv, deltaenv, dir, NULL,
 					       fhin, fhout, fherr);
 		free(prog);
 	}
@@ -2209,7 +2210,7 @@ static int try_shell_exec(const char *cmd, char *const *argv)
 		argv2[0] = (char *)cmd;	/* full path to the script file */
 		COPY_ARRAY(&argv2[1], &argv[1], argc);
 		exec_id = trace2_exec(prog, (const char **)argv2);
-		pid = mingw_spawnv(prog, (const char **)argv2, 1);
+		pid = mingw_spawnv(prog, (const char **)argv2, interpr);
 		if (pid >= 0) {
 			int status;
 			if (waitpid(pid, &status, 0) < 0)
@@ -2233,7 +2234,7 @@ int mingw_execv(const char *cmd, char *const *argv)
 		int exec_id;
 
 		exec_id = trace2_exec(cmd, (const char **)argv);
-		pid = mingw_spawnv(cmd, (const char **)argv, 0);
+		pid = mingw_spawnv(cmd, (const char **)argv, NULL);
 		if (pid < 0) {
 			trace2_exec_result(exec_id, -1);
 			return -1;

From 4127450b0fc63fc763bf14b595904cd3fcdeecb5 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 20 Jul 2017 20:41:29 +0200
Subject: [PATCH 225/259] mingw: when path_lookup() failed, try BusyBox

BusyBox comes with a ton of applets ("applet" being the identical
concept to Git's "builtins"). And similar to Git's builtins, the applets
can be called via `busybox <command>`, or the BusyBox executable can be
copied/hard-linked to the command name.

The similarities do not end here. Just as with Git's builtins, it is
problematic that BusyBox' hard-linked applets cannot easily be put into
a .zip file: .zip archives have no concept of hard-links and therefore
would store identical copies (and also extract identical copies,
"inflating" the archive unnecessarily).

To counteract that issue, MinGit already ships without hard-linked
copies of the builtins, and the plan is to do the same with BusyBox'
applets: simply ship busybox.exe as single executable, without
hard-linked applets.

To accommodate that, Git is being taught by this commit a very special
trick, exploiting the fact that it is possible to call an executable
with a command-line whose argv[0] is different from the executable's
name: when `sh` is to be spawned, and no `sh` is found in the PATH, but
busybox.exe is, use that executable (with unchanged argv).

Likewise, if any executable to be spawned is not on the PATH, but
busybox.exe is found, parse the output of `busybox.exe --help` to find
out what applets are included, and if the command matches an included
applet name, use busybox.exe to execute it.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c   | 63 ++++++++++++++++++++++++++++++++++++++++++++++++
 t/t0014-alias.sh |  2 +-
 2 files changed, 64 insertions(+), 1 deletion(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 4c964d38280b2e..e61981cdaafa10 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -24,6 +24,7 @@
 #include "../repository.h"
 #include "win32/fscache.h"
 #include "../attr.h"
+#include "../string-list.h"
 
 #define HCAST(type, handle) ((type)(intptr_t)handle)
 
@@ -1665,6 +1666,65 @@ static char *lookup_prog(const char *dir, int dirlen, const char *cmd,
 	return NULL;
 }
 
+static char *path_lookup(const char *cmd, int exe_only);
+
+static char *is_busybox_applet(const char *cmd)
+{
+	static struct string_list applets = STRING_LIST_INIT_DUP;
+	static char *busybox_path;
+	static int busybox_path_initialized;
+
+	/* Avoid infinite loop */
+	if (!strncasecmp(cmd, "busybox", 7) &&
+	    (!cmd[7] || !strcasecmp(cmd + 7, ".exe")))
+		return NULL;
+
+	if (!busybox_path_initialized) {
+		busybox_path = path_lookup("busybox.exe", 1);
+		busybox_path_initialized = 1;
+	}
+
+	/* Assume that sh is compiled in... */
+	if (!busybox_path || !strcasecmp(cmd, "sh"))
+		return xstrdup_or_null(busybox_path);
+
+	if (!applets.nr) {
+		struct child_process cp = CHILD_PROCESS_INIT;
+		struct strbuf buf = STRBUF_INIT;
+		char *p;
+
+		strvec_pushl(&cp.args, busybox_path, "--help", NULL);
+
+		if (capture_command(&cp, &buf, 2048)) {
+			string_list_append(&applets, "");
+			return NULL;
+		}
+
+		/* parse output */
+		p = strstr(buf.buf, "Currently defined functions:\n");
+		if (!p) {
+			warning("Could not parse output of busybox --help");
+			string_list_append(&applets, "");
+			return NULL;
+		}
+		p = strchrnul(p, '\n');
+		for (;;) {
+			size_t len;
+
+			p += strspn(p, "\n\t ,");
+			len = strcspn(p, "\n\t ,");
+			if (!len)
+				break;
+			p[len] = '\0';
+			string_list_insert(&applets, p);
+			p = p + len + 1;
+		}
+	}
+
+	return string_list_has_string(&applets, cmd) ?
+		xstrdup(busybox_path) : NULL;
+}
+
 /*
  * Determines the absolute path of cmd using the split path in path.
  * If cmd contains a slash or backslash, no lookup is performed.
@@ -1693,6 +1753,9 @@ static char *path_lookup(const char *cmd, int exe_only)
 		path = sep + 1;
 	}
 
+	if (!prog && !isexe)
+		prog = is_busybox_applet(cmd);
+
 	return prog;
 }
 
diff --git a/t/t0014-alias.sh b/t/t0014-alias.sh
index 30708146887d19..56d70b73e1c165 100755
--- a/t/t0014-alias.sh
+++ b/t/t0014-alias.sh
@@ -39,7 +39,7 @@ test_expect_success 'looping aliases - internal execution' '
 
 test_expect_success 'run-command formats empty args properly' '
 	test_must_fail env GIT_TRACE=1 git frotz a "" b " " c 2>actual.raw &&
-	sed -ne "/run_command:/s/.*trace: run_command: //p" actual.raw >actual &&
+	sed -ne "/run_command: git-frotz/s/.*trace: run_command: //p" actual.raw >actual &&
 	echo "git-frotz a '\'''\'' b '\'' '\'' c" >expect &&
 	test_cmp expect actual
 '

From 864e8d8e2dad28354570293e5f7cf82a0a6dd8f6 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sat, 5 Aug 2017 22:23:36 +0200
Subject: [PATCH 226/259] test-lib: avoid unnecessary Perl invocation

It is a bit strange, and even undesirable, to require Perl just to run
the test suite even when NO_PERL was set.

This patch does not fix this problem by any stretch of imagination.
However, it fixes *the* Perl invocation that *every single* test script
has to run.

While at it, it makes the source code also more grep'able, as the code
that unsets some, but not all, GIT_* environment variables just became a
*lot* more explicit. And all that while still reducing the total number
of lines.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/test-lib.sh | 29 ++++++++++++-----------------
 1 file changed, 12 insertions(+), 17 deletions(-)

diff --git a/t/test-lib.sh b/t/test-lib.sh
index 54247604cbc76e..36a9e26938a42e 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -500,23 +500,18 @@ EDITOR=:
 # /usr/xpg4/bin/sh and /bin/ksh to bail out.  So keep the unsets
 # deriving from the command substitution clustered with the other
 # ones.
-unset VISUAL EMAIL LANGUAGE $("$PERL_PATH" -e '
-	my @env = keys %ENV;
-	my $ok = join("|", qw(
-		TRACE
-		DEBUG
-		TEST
-		.*_TEST
-		PROVE
-		VALGRIND
-		UNZIP
-		PERF_
-		CURL_VERBOSE
-		TRACE_CURL
-	));
-	my @vars = grep(/^GIT_/ && !/^GIT_($ok)/o, @env);
-	print join("\n", @vars);
-')
+unset VISUAL EMAIL LANGUAGE $(env | sed -n \
+	-e '/^GIT_TRACE/d' \
+	-e '/^GIT_DEBUG/d' \
+	-e '/^GIT_TEST/d' \
+	-e '/^GIT_.*_TEST/d' \
+	-e '/^GIT_PROVE/d' \
+	-e '/^GIT_VALGRIND/d' \
+	-e '/^GIT_UNZIP/d' \
+	-e '/^GIT_PERF_/d' \
+	-e '/^GIT_CURL_VERBOSE/d' \
+	-e '/^GIT_TRACE_CURL/d' \
+	-e 's/^\(GIT_[^=]*\)=.*/\1/p')
 unset XDG_CACHE_HOME
 unset XDG_CONFIG_HOME
 unset GITPERLLIB

From 054273289a6da8958dd0a2ee735fe2092817d134 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 20 Jul 2017 22:18:56 +0200
Subject: [PATCH 227/259] test-tool: learn to act as a drop-in replacement for
 `iconv`

It is convenient to assume that everybody who wants to build & test Git
has access to a working `iconv` executable (after all, we already pretty
much require libiconv).

However, that limits esoteric test scenarios such as Git for Windows',
where an end user installation has to ship with `iconv` for the sole
purpose of being testable. That payload serves no other purpose.

So let's just have a test helper (to be able to test Git, the test
helpers have to be available, after all) to act as `iconv` replacement.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 Makefile              |  1 +
 t/helper/test-iconv.c | 47 +++++++++++++++++++++++++++++++++++++++++++
 t/helper/test-tool.c  |  1 +
 t/helper/test-tool.h  |  1 +
 4 files changed, 50 insertions(+)
 create mode 100644 t/helper/test-iconv.c

diff --git a/Makefile b/Makefile
index ca0757217904e7..522c8a612c9882 100644
--- a/Makefile
+++ b/Makefile
@@ -808,6 +808,7 @@ TEST_BUILTINS_OBJS += test-hash-speed.o
 TEST_BUILTINS_OBJS += test-hash.o
 TEST_BUILTINS_OBJS += test-hashmap.o
 TEST_BUILTINS_OBJS += test-hexdump.o
+TEST_BUILTINS_OBJS += test-iconv.o
 TEST_BUILTINS_OBJS += test-json-writer.o
 TEST_BUILTINS_OBJS += test-lazy-init-name-hash.o
 TEST_BUILTINS_OBJS += test-match-trees.o
diff --git a/t/helper/test-iconv.c b/t/helper/test-iconv.c
new file mode 100644
index 00000000000000..d3c772fddf990b
--- /dev/null
+++ b/t/helper/test-iconv.c
@@ -0,0 +1,47 @@
+#include "test-tool.h"
+#include "git-compat-util.h"
+#include "strbuf.h"
+#include "gettext.h"
+#include "parse-options.h"
+#include "utf8.h"
+
+int cmd__iconv(int argc, const char **argv)
+{
+	struct strbuf buf = STRBUF_INIT;
+	char *from = NULL, *to = NULL, *p;
+	size_t len;
+	int ret = 0;
+	const char * const iconv_usage[] = {
+		N_("test-helper --iconv [<options>]"),
+		NULL
+	};
+	struct option options[] = {
+		OPT_STRING('f', "from-code", &from, "encoding", "from"),
+		OPT_STRING('t', "to-code", &to, "encoding", "to"),
+		OPT_END()
+	};
+
+	argc = parse_options(argc, argv, NULL, options,
+			iconv_usage, 0);
+
+	if (argc > 1 || !from || !to)
+		usage_with_options(iconv_usage, options);
+
+	if (!argc) {
+		if (strbuf_read(&buf, 0, 2048) < 0)
+			die_errno("Could not read from stdin");
+	} else if (strbuf_read_file(&buf, argv[0], 2048) < 0)
+		die_errno("Could not read from '%s'", argv[0]);
+
+	p = reencode_string_len(buf.buf, buf.len, to, from, &len);
+	if (!p)
+		die_errno("Could not reencode");
+	if (write(1, p, len) < 0)
+		ret = !!error_errno("Could not write %"PRIuMAX" bytes",
+				    (uintmax_t)len);
+
+	strbuf_release(&buf);
+	free(p);
+
+	return ret;
+}
diff --git a/t/helper/test-tool.c b/t/helper/test-tool.c
index 5f7ed5f57d63d2..eeb10fae59cf8b 100644
--- a/t/helper/test-tool.c
+++ b/t/helper/test-tool.c
@@ -38,6 +38,7 @@ static struct test_cmd cmds[] = {
 	{ "hashmap", cmd__hashmap },
 	{ "hash-speed", cmd__hash_speed },
 	{ "hexdump", cmd__hexdump },
+	{ "iconv", cmd__iconv },
 	{ "json-writer", cmd__json_writer },
 	{ "lazy-init-name-hash", cmd__lazy_init_name_hash },
 	{ "match-trees", cmd__match_trees },
diff --git a/t/helper/test-tool.h b/t/helper/test-tool.h
index 858361531bba25..bd5f26d8a7c3a2 100644
--- a/t/helper/test-tool.h
+++ b/t/helper/test-tool.h
@@ -32,6 +32,7 @@ int cmd__getcwd(int argc, const char **argv);
 int cmd__hashmap(int argc, const char **argv);
 int cmd__hash_speed(int argc, const char **argv);
 int cmd__hexdump(int argc, const char **argv);
+int cmd__iconv(int argc, const char **argv);
 int cmd__json_writer(int argc, const char **argv);
 int cmd__lazy_init_name_hash(int argc, const char **argv);
 int cmd__match_trees(int argc, const char **argv);

From 2d2de6c295f6708f193f94905ea0694572499426 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 20 Jul 2017 22:25:21 +0200
Subject: [PATCH 228/259] tests(mingw): if `iconv` is unavailable, use
 `test-helper --iconv`

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/test-lib.sh | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/t/test-lib.sh b/t/test-lib.sh
index 36a9e26938a42e..ee91f6c3b23f2e 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -1721,6 +1721,12 @@ case $uname_s in
 	test_set_prereq GREP_STRIPS_CR
 	test_set_prereq WINDOWS
 	GIT_TEST_CMP="GIT_DIR=/dev/null git diff --no-index --ignore-cr-at-eol --"
+	if ! type iconv >/dev/null 2>&1
+	then
+		iconv () {
+			test-tool iconv "$@"
+		}
+	fi
 	;;
 *CYGWIN*)
 	test_set_prereq POSIXPERM

From d2062ccf49e854aa1cb56e2a24ed017924378685 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 11 Oct 2018 23:55:44 +0200
Subject: [PATCH 229/259] gitattributes: mark .png files as binary

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 .gitattributes | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.gitattributes b/.gitattributes
index 158c3d45c4c10c..60d486390b91df 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -6,6 +6,7 @@
 *.pm text eol=lf diff=perl
 *.py text eol=lf diff=python
 *.bat text eol=crlf
+*.png binary
 CODE_OF_CONDUCT.md -whitespace
 /Documentation/**/*.txt text eol=lf
 /command-list.txt text eol=lf

From fb41649bd51d7173c82aa93482857eeda6322fe7 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sat, 5 Aug 2017 20:28:37 +0200
Subject: [PATCH 230/259] tests: move test PNGs into t/lib-diff/

We already have a directory where we store files intended for use by
multiple test scripts. The same directory is a better home for the
test-binary-*.png files than t/.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/{ => lib-diff}/test-binary-1.png | Bin
 t/{ => lib-diff}/test-binary-2.png | Bin
 t/t3307-notes-man.sh               |   2 +-
 t/t3903-stash.sh                   |   2 +-
 t/t4012-diff-binary.sh             |   2 +-
 t/t4049-diff-stat-count.sh         |   2 +-
 t/t4108-apply-threeway.sh          |  12 ++++++------
 t/t6403-merge-file.sh              |   4 ++--
 t/t6407-merge-binary.sh            |   2 +-
 t/t9200-git-cvsexportcommit.sh     |  14 +++++++-------
 10 files changed, 20 insertions(+), 20 deletions(-)
 rename t/{ => lib-diff}/test-binary-1.png (100%)
 rename t/{ => lib-diff}/test-binary-2.png (100%)

diff --git a/t/test-binary-1.png b/t/lib-diff/test-binary-1.png
similarity index 100%
rename from t/test-binary-1.png
rename to t/lib-diff/test-binary-1.png
diff --git a/t/test-binary-2.png b/t/lib-diff/test-binary-2.png
similarity index 100%
rename from t/test-binary-2.png
rename to t/lib-diff/test-binary-2.png
diff --git a/t/t3307-notes-man.sh b/t/t3307-notes-man.sh
index ae316502c4531b..2b6894df0a247a 100755
--- a/t/t3307-notes-man.sh
+++ b/t/t3307-notes-man.sh
@@ -27,7 +27,7 @@ test_expect_success 'example 1: notes to add an Acked-by line' '
 '
 
 test_expect_success 'example 2: binary notes' '
-	cp "$TEST_DIRECTORY"/test-binary-1.png . &&
+	cp "$TEST_DIRECTORY"/lib-diff/test-binary-1.png . &&
 	git checkout B &&
 	blob=$(git hash-object -w test-binary-1.png) &&
 	git notes --ref=logo add -C "$blob" &&
diff --git a/t/t3903-stash.sh b/t/t3903-stash.sh
index 74666ff3e4b2b8..b18113d303edca 100755
--- a/t/t3903-stash.sh
+++ b/t/t3903-stash.sh
@@ -1345,7 +1345,7 @@ test_expect_success 'stash -- <subdir> works with binary files' '
 	git reset &&
 	>subdir/untracked &&
 	>subdir/tracked &&
-	cp "$TEST_DIRECTORY"/test-binary-1.png subdir/tracked-binary &&
+	cp "$TEST_DIRECTORY"/lib-diff/test-binary-1.png subdir/tracked-binary &&
 	git add subdir/tracked* &&
 	git stash -- subdir/ &&
 	test_path_is_missing subdir/tracked &&
diff --git a/t/t4012-diff-binary.sh b/t/t4012-diff-binary.sh
index c64d9d2f405e1e..b3b9adc3c034fd 100755
--- a/t/t4012-diff-binary.sh
+++ b/t/t4012-diff-binary.sh
@@ -20,7 +20,7 @@ test_expect_success 'prepare repository' '
 	echo AIT >a && echo BIT >b && echo CIT >c && echo DIT >d &&
 	git update-index --add a b c d &&
 	echo git >a &&
-	cat "$TEST_DIRECTORY"/test-binary-1.png >b &&
+	cat "$TEST_DIRECTORY"/lib-diff/test-binary-1.png >b &&
 	echo git >c &&
 	cat b b >d
 '
diff --git a/t/t4049-diff-stat-count.sh b/t/t4049-diff-stat-count.sh
index 0a4fc735d44ad5..6c028646485971 100755
--- a/t/t4049-diff-stat-count.sh
+++ b/t/t4049-diff-stat-count.sh
@@ -34,7 +34,7 @@ test_expect_success 'binary changes do not count in lines' '
 	git reset --hard &&
 	echo a >a &&
 	echo c >c &&
-	cat "$TEST_DIRECTORY"/test-binary-1.png >d &&
+	cat "$TEST_DIRECTORY"/lib-diff/test-binary-1.png >d &&
 	cat >expect <<-\EOF &&
 	 a | 1 +
 	 c | 1 +
diff --git a/t/t4108-apply-threeway.sh b/t/t4108-apply-threeway.sh
index c558282bc09475..1c85e7051d5f72 100755
--- a/t/t4108-apply-threeway.sh
+++ b/t/t4108-apply-threeway.sh
@@ -232,11 +232,11 @@ test_expect_success 'apply with --3way --cached and conflicts' '
 
 test_expect_success 'apply binary file patch' '
 	git reset --hard main &&
-	cp "$TEST_DIRECTORY/test-binary-1.png" bin.png &&
+	cp "$TEST_DIRECTORY/lib-diff/test-binary-1.png" bin.png &&
 	git add bin.png &&
 	git commit -m "add binary file" &&
 
-	cp "$TEST_DIRECTORY/test-binary-2.png" bin.png &&
+	cp "$TEST_DIRECTORY/lib-diff/test-binary-2.png" bin.png &&
 
 	git diff --binary >bin.diff &&
 	git reset --hard &&
@@ -247,11 +247,11 @@ test_expect_success 'apply binary file patch' '
 
 test_expect_success 'apply binary file patch with 3way' '
 	git reset --hard main &&
-	cp "$TEST_DIRECTORY/test-binary-1.png" bin.png &&
+	cp "$TEST_DIRECTORY/lib-diff/test-binary-1.png" bin.png &&
 	git add bin.png &&
 	git commit -m "add binary file" &&
 
-	cp "$TEST_DIRECTORY/test-binary-2.png" bin.png &&
+	cp "$TEST_DIRECTORY/lib-diff/test-binary-2.png" bin.png &&
 
 	git diff --binary >bin.diff &&
 	git reset --hard &&
@@ -262,11 +262,11 @@ test_expect_success 'apply binary file patch with 3way' '
 
 test_expect_success 'apply full-index patch with 3way' '
 	git reset --hard main &&
-	cp "$TEST_DIRECTORY/test-binary-1.png" bin.png &&
+	cp "$TEST_DIRECTORY/lib-diff/test-binary-1.png" bin.png &&
 	git add bin.png &&
 	git commit -m "add binary file" &&
 
-	cp "$TEST_DIRECTORY/test-binary-2.png" bin.png &&
+	cp "$TEST_DIRECTORY/lib-diff/test-binary-2.png" bin.png &&
 
 	git diff --full-index >bin.diff &&
 	git reset --hard &&
diff --git a/t/t6403-merge-file.sh b/t/t6403-merge-file.sh
index fb872c5a1136fc..6308d3b85f0111 100755
--- a/t/t6403-merge-file.sh
+++ b/t/t6403-merge-file.sh
@@ -356,12 +356,12 @@ test_expect_success "expected conflict markers" '
 
 test_expect_success 'binary files cannot be merged' '
 	test_must_fail git merge-file -p \
-		orig.txt "$TEST_DIRECTORY"/test-binary-1.png new1.txt 2> merge.err &&
+		orig.txt "$TEST_DIRECTORY"/lib-diff/test-binary-1.png new1.txt 2> merge.err &&
 	grep "Cannot merge binary files" merge.err
 '
 
 test_expect_success 'binary files cannot be merged with --object-id' '
-	cp "$TEST_DIRECTORY"/test-binary-1.png . &&
+	cp "$TEST_DIRECTORY"/lib-diff/test-binary-1.png . &&
 	git add orig.txt new1.txt test-binary-1.png &&
 	test_must_fail git merge-file --object-id \
 		:orig.txt :test-binary-1.png :new1.txt 2> merge.err &&
diff --git a/t/t6407-merge-binary.sh b/t/t6407-merge-binary.sh
index 0753fc95f45efb..914014e1a9c551 100755
--- a/t/t6407-merge-binary.sh
+++ b/t/t6407-merge-binary.sh
@@ -10,7 +10,7 @@ TEST_PASSES_SANITIZE_LEAK=true
 
 test_expect_success setup '
 
-	cat "$TEST_DIRECTORY"/test-binary-1.png >m &&
+	cat "$TEST_DIRECTORY"/lib-diff/test-binary-1.png >m &&
 	git add m &&
 	git ls-files -s | sed -e "s/ 0	/ 1	/" >E1 &&
 	test_tick &&
diff --git a/t/t9200-git-cvsexportcommit.sh b/t/t9200-git-cvsexportcommit.sh
index 3d4842164c8915..3dc8d77433f6ea 100755
--- a/t/t9200-git-cvsexportcommit.sh
+++ b/t/t9200-git-cvsexportcommit.sh
@@ -55,8 +55,8 @@ test_expect_success 'New file' '
 	mkdir A B C D E F &&
 	echo hello1 >A/newfile1.txt &&
 	echo hello2 >B/newfile2.txt &&
-	cp "$TEST_DIRECTORY"/test-binary-1.png C/newfile3.png &&
-	cp "$TEST_DIRECTORY"/test-binary-1.png D/newfile4.png &&
+	cp "$TEST_DIRECTORY"/lib-diff/test-binary-1.png C/newfile3.png &&
+	cp "$TEST_DIRECTORY"/lib-diff/test-binary-1.png D/newfile4.png &&
 	git add A/newfile1.txt &&
 	git add B/newfile2.txt &&
 	git add C/newfile3.png &&
@@ -81,8 +81,8 @@ test_expect_success 'Remove two files, add two and update two' '
 	rm -f B/newfile2.txt &&
 	rm -f C/newfile3.png &&
 	echo Hello5  >E/newfile5.txt &&
-	cp "$TEST_DIRECTORY"/test-binary-2.png D/newfile4.png &&
-	cp "$TEST_DIRECTORY"/test-binary-1.png F/newfile6.png &&
+	cp "$TEST_DIRECTORY"/lib-diff/test-binary-2.png D/newfile4.png &&
+	cp "$TEST_DIRECTORY"/lib-diff/test-binary-1.png F/newfile6.png &&
 	git add E/newfile5.txt &&
 	git add F/newfile6.png &&
 	git commit -a -m "Test: Remove, add and update" &&
@@ -170,7 +170,7 @@ test_expect_success 'New file with spaces in file name' '
 	mkdir "G g" &&
 	echo ok then >"G g/with spaces.txt" &&
 	git add "G g/with spaces.txt" && \
-	cp "$TEST_DIRECTORY"/test-binary-1.png "G g/with spaces.png" && \
+	cp "$TEST_DIRECTORY"/lib-diff/test-binary-1.png "G g/with spaces.png" && \
 	git add "G g/with spaces.png" &&
 	git commit -a -m "With spaces" &&
 	id=$(git rev-list --max-count=1 HEAD) &&
@@ -182,7 +182,7 @@ test_expect_success 'New file with spaces in file name' '
 
 test_expect_success 'Update file with spaces in file name' '
 	echo Ok then >>"G g/with spaces.txt" &&
-	cat "$TEST_DIRECTORY"/test-binary-1.png >>"G g/with spaces.png" && \
+	cat "$TEST_DIRECTORY"/lib-diff/test-binary-1.png >>"G g/with spaces.png" && \
 	git add "G g/with spaces.png" &&
 	git commit -a -m "Update with spaces" &&
 	id=$(git rev-list --max-count=1 HEAD) &&
@@ -207,7 +207,7 @@ test_expect_success !MINGW 'File with non-ascii file name' '
 	mkdir -p Å/goo/a/b/c/d/e/f/g/h/i/j/k/l/m/n/o/p/q/r/s/t/u/v/w/x/y/z/å/ä/ö &&
 	echo Foo >Å/goo/a/b/c/d/e/f/g/h/i/j/k/l/m/n/o/p/q/r/s/t/u/v/w/x/y/z/å/ä/ö/gårdetsågårdet.txt &&
 	git add Å/goo/a/b/c/d/e/f/g/h/i/j/k/l/m/n/o/p/q/r/s/t/u/v/w/x/y/z/å/ä/ö/gårdetsågårdet.txt &&
-	cp "$TEST_DIRECTORY"/test-binary-1.png Å/goo/a/b/c/d/e/f/g/h/i/j/k/l/m/n/o/p/q/r/s/t/u/v/w/x/y/z/å/ä/ö/gårdetsågårdet.png &&
+	cp "$TEST_DIRECTORY"/lib-diff/test-binary-1.png Å/goo/a/b/c/d/e/f/g/h/i/j/k/l/m/n/o/p/q/r/s/t/u/v/w/x/y/z/å/ä/ö/gårdetsågårdet.png &&
 	git add Å/goo/a/b/c/d/e/f/g/h/i/j/k/l/m/n/o/p/q/r/s/t/u/v/w/x/y/z/å/ä/ö/gårdetsågårdet.png &&
 	git commit -a -m "Går det så går det" && \
 	id=$(git rev-list --max-count=1 HEAD) &&

From a78bf1fe8d7289494b7cad1a76cf8da824e336c2 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 18 Jul 2017 01:15:40 +0200
Subject: [PATCH 231/259] tests: only override sort & find if there are usable
 ones in /usr/bin/

The idea is to allow running the test suite on MinGit with BusyBox
installed in /mingw64/bin/sh.exe. In that case, we will want to exclude
sort & find (and other Unix utilities) from being bundled.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 git-sh-setup.sh | 21 ++++++++++++++-------
 t/test-lib.sh   | 21 ++++++++++++++-------
 2 files changed, 28 insertions(+), 14 deletions(-)

diff --git a/git-sh-setup.sh b/git-sh-setup.sh
index ce273fe0e48d99..785a4cbfa9c65e 100644
--- a/git-sh-setup.sh
+++ b/git-sh-setup.sh
@@ -292,13 +292,20 @@ create_virtual_base() {
 # Platform specific tweaks to work around some commands
 case $(uname -s) in
 *MINGW*)
-	# Windows has its own (incompatible) sort and find
-	sort () {
-		/usr/bin/sort "$@"
-	}
-	find () {
-		/usr/bin/find "$@"
-	}
+	if test -x /usr/bin/sort
+	then
+		# Windows has its own (incompatible) sort; override
+		sort () {
+			/usr/bin/sort "$@"
+		}
+	fi
+	if test -x /usr/bin/find
+	then
+		# Windows has its own (incompatible) find; override
+		find () {
+			/usr/bin/find "$@"
+		}
+	fi
 	# git sees Windows-style pwd
 	pwd () {
 		builtin pwd -W
diff --git a/t/test-lib.sh b/t/test-lib.sh
index ee91f6c3b23f2e..c501acf7666044 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -1701,13 +1701,20 @@ fi
 uname_s=$(uname -s)
 case $uname_s in
 *MINGW*)
-	# Windows has its own (incompatible) sort and find
-	sort () {
-		/usr/bin/sort "$@"
-	}
-	find () {
-		/usr/bin/find "$@"
-	}
+	if test -x /usr/bin/sort
+	then
+		# Windows has its own (incompatible) sort; override
+		sort () {
+			/usr/bin/sort "$@"
+		}
+	fi
+	if test -x /usr/bin/find
+	then
+		# Windows has its own (incompatible) find; override
+		find () {
+			/usr/bin/find "$@"
+		}
+	fi
 	# git sees Windows-style pwd
 	pwd () {
 		builtin pwd -W

From 06fc9fcb88e632ed53e8c7df113e2a37042bf4f0 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 19 Nov 2018 20:34:13 +0100
Subject: [PATCH 232/259] tests: use the correct path separator with BusyBox

BusyBox-w32 is a true Win32 application, i.e. it does not come with a
POSIX emulation layer.

That also means that it does *not* use the Unix convention of separating
the entries in the PATH variable using colons, but semicolons.

However, there are also BusyBox ports to Windows which use a POSIX
emulation layer such as Cygwin's or MSYS2's runtime, i.e. using colons
as PATH separators.

As a tell-tale, let's use the presence of semicolons in the PATH
variable: on Unix, it is highly unlikely that it contains semicolons,
and on Windows (without POSIX emulation), it is virtually guaranteed, as
everybody should have both $SYSTEMROOT and $SYSTEMROOT/system32 in their
PATH.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/interop/interop-lib.sh    |  8 ++++++--
 t/lib-proto-disable.sh      |  2 +-
 t/t0021-conversion.sh       |  2 +-
 t/t0060-path-utils.sh       | 24 ++++++++++++------------
 t/t0061-run-command.sh      |  6 +++---
 t/t0300-credentials.sh      |  2 +-
 t/t1504-ceiling-dirs.sh     | 10 +++++-----
 t/t2300-cd-to-toplevel.sh   |  2 +-
 t/t3418-rebase-continue.sh  |  4 ++--
 t/t5615-alternate-env.sh    |  4 ++--
 t/t5802-connect-helper.sh   |  2 +-
 t/t7006-pager.sh            |  4 ++--
 t/t7606-merge-custom.sh     |  2 +-
 t/t7811-grep-open.sh        |  2 +-
 t/t9003-help-autocorrect.sh |  2 +-
 t/t9800-git-p4-basic.sh     |  2 +-
 t/test-lib.sh               | 17 +++++++++++++----
 17 files changed, 54 insertions(+), 41 deletions(-)

diff --git a/t/interop/interop-lib.sh b/t/interop/interop-lib.sh
index 62f4481b6e4097..c4f8c8e2d8ff92 100644
--- a/t/interop/interop-lib.sh
+++ b/t/interop/interop-lib.sh
@@ -4,6 +4,10 @@
 . ../../GIT-BUILD-OPTIONS
 INTEROP_ROOT=$(pwd)
 BUILD_ROOT=$INTEROP_ROOT/build
+case "$PATH" in
+*\;*) PATH_SEP=\; ;;
+*) PATH_SEP=: ;;
+esac
 
 build_version () {
 	if test -z "$1"
@@ -57,7 +61,7 @@ wrap_git () {
 	write_script "$1" <<-EOF
 	GIT_EXEC_PATH="$2"
 	export GIT_EXEC_PATH
-	PATH="$2:\$PATH"
+	PATH="$2$PATH_SEP\$PATH"
 	export GIT_EXEC_PATH
 	exec git "\$@"
 	EOF
@@ -71,7 +75,7 @@ generate_wrappers () {
 	echo >&2 fatal: test tried to run generic git: $*
 	exit 1
 	EOF
-	PATH=$(pwd)/.bin:$PATH
+	PATH=$(pwd)/.bin$PATH_SEP$PATH
 }
 
 VERSION_A=${GIT_TEST_VERSION_A:-$VERSION_A}
diff --git a/t/lib-proto-disable.sh b/t/lib-proto-disable.sh
index 890622be81642b..9db481e1be15b2 100644
--- a/t/lib-proto-disable.sh
+++ b/t/lib-proto-disable.sh
@@ -214,7 +214,7 @@ setup_ext_wrapper () {
 		cd "$TRASH_DIRECTORY/remote" &&
 		eval "$*"
 		EOF
-		PATH=$TRASH_DIRECTORY:$PATH &&
+		PATH=$TRASH_DIRECTORY$PATH_SEP$PATH &&
 		export TRASH_DIRECTORY
 	'
 }
diff --git a/t/t0021-conversion.sh b/t/t0021-conversion.sh
index 0b4997022bf88a..8ba840cdc138cd 100755
--- a/t/t0021-conversion.sh
+++ b/t/t0021-conversion.sh
@@ -8,7 +8,7 @@ export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-terminal.sh
 
-PATH=$PWD:$PATH
+PATH=$PWD$PATH_SEP$PATH
 TEST_ROOT="$(pwd)"
 
 write_script <<\EOF "$TEST_ROOT/rot13.sh"
diff --git a/t/t0060-path-utils.sh b/t/t0060-path-utils.sh
index 54123c5ab63a6a..61927b98a21523 100755
--- a/t/t0060-path-utils.sh
+++ b/t/t0060-path-utils.sh
@@ -148,25 +148,25 @@ ancestor /foo /fo -1
 ancestor /foo /foo -1
 ancestor /foo /bar -1
 ancestor /foo /foo/bar -1
-ancestor /foo /foo:/bar -1
-ancestor /foo /:/foo:/bar 0
-ancestor /foo /foo:/:/bar 0
-ancestor /foo /:/bar:/foo 0
+ancestor /foo "/foo$PATH_SEP/bar" -1
+ancestor /foo "/$PATH_SEP/foo$PATH_SEP/bar" 0
+ancestor /foo "/foo$PATH_SEP/$PATH_SEP/bar" 0
+ancestor /foo "/$PATH_SEP/bar$PATH_SEP/foo" 0
 ancestor /foo/bar / 0
 ancestor /foo/bar /fo -1
 ancestor /foo/bar /foo 4
 ancestor /foo/bar /foo/ba -1
-ancestor /foo/bar /:/fo 0
-ancestor /foo/bar /foo:/foo/ba 4
+ancestor /foo/bar "/$PATH_SEP/fo" 0
+ancestor /foo/bar "/foo$PATH_SEP/foo/ba" 4
 ancestor /foo/bar /bar -1
 ancestor /foo/bar /fo -1
-ancestor /foo/bar /foo:/bar 4
-ancestor /foo/bar /:/foo:/bar 4
-ancestor /foo/bar /foo:/:/bar 4
-ancestor /foo/bar /:/bar:/fo 0
-ancestor /foo/bar /:/bar 0
+ancestor /foo/bar "/foo$PATH_SEP/bar" 4
+ancestor /foo/bar "/$PATH_SEP/foo$PATH_SEP/bar" 4
+ancestor /foo/bar "/foo$PATH_SEP/$PATH_SEP/bar" 4
+ancestor /foo/bar "/$PATH_SEP/bar$PATH_SEP/fo" 0
+ancestor /foo/bar "/$PATH_SEP/bar" 0
 ancestor /foo/bar /foo 4
-ancestor /foo/bar /foo:/bar 4
+ancestor /foo/bar "/foo$PATH_SEP/bar" 4
 ancestor /foo/bar /bar -1
 
 # Windows-specific: DOS drives, network shares
diff --git a/t/t0061-run-command.sh b/t/t0061-run-command.sh
index 20986b693cfbe8..0a9926c50c421f 100755
--- a/t/t0061-run-command.sh
+++ b/t/t0061-run-command.sh
@@ -70,7 +70,7 @@ test_expect_success 'run_command does not try to execute a directory' '
 	cat bin2/greet
 	EOF
 
-	PATH=$PWD/bin1:$PWD/bin2:$PATH \
+	PATH=$PWD/bin1$PATH_SEP$PWD/bin2$PATH_SEP$PATH \
 		test-tool run-command run-command greet >actual 2>err &&
 	test_cmp bin2/greet actual &&
 	test_must_be_empty err
@@ -87,7 +87,7 @@ test_expect_success POSIXPERM 'run_command passes over non-executable file' '
 	cat bin2/greet
 	EOF
 
-	PATH=$PWD/bin1:$PWD/bin2:$PATH \
+	PATH=$PWD/bin1$PATH_SEP$PWD/bin2$PATH_SEP$PATH \
 		test-tool run-command run-command greet >actual 2>err &&
 	test_cmp bin2/greet actual &&
 	test_must_be_empty err
@@ -107,7 +107,7 @@ test_expect_success POSIXPERM,SANITY 'unreadable directory in PATH' '
 	git config alias.nitfol "!echo frotz" &&
 	chmod a-rx local-command &&
 	(
-		PATH=./local-command:$PATH &&
+		PATH=./local-command$PATH_SEP$PATH &&
 		git nitfol >actual
 	) &&
 	echo frotz >expect &&
diff --git a/t/t0300-credentials.sh b/t/t0300-credentials.sh
index 6a76b7fdbd4557..14b1d2f4937e81 100755
--- a/t/t0300-credentials.sh
+++ b/t/t0300-credentials.sh
@@ -77,7 +77,7 @@ test_expect_success 'setup helper scripts' '
 	test -z "$pexpiry" || echo password_expiry_utc=$pexpiry
 	EOF
 
-	PATH="$PWD:$PATH"
+	PATH="$PWD$PATH_SEP$PATH"
 '
 
 test_expect_success 'credential_fill invokes helper' '
diff --git a/t/t1504-ceiling-dirs.sh b/t/t1504-ceiling-dirs.sh
index c1679e31d8afca..b47a23f8a9d6b1 100755
--- a/t/t1504-ceiling-dirs.sh
+++ b/t/t1504-ceiling-dirs.sh
@@ -85,9 +85,9 @@ then
 	GIT_CEILING_DIRECTORIES="$TRASH_ROOT/top/"
 	test_fail subdir_ceil_at_top_slash
 
-	GIT_CEILING_DIRECTORIES=":$TRASH_ROOT/top"
+	GIT_CEILING_DIRECTORIES="$PATH_SEP$TRASH_ROOT/top"
 	test_prefix subdir_ceil_at_top_no_resolve "sub/dir/"
-	GIT_CEILING_DIRECTORIES=":$TRASH_ROOT/top/"
+	GIT_CEILING_DIRECTORIES="$PATH_SEP$TRASH_ROOT/top/"
 	test_prefix subdir_ceil_at_top_slash_no_resolve "sub/dir/"
 fi
 
@@ -117,13 +117,13 @@ GIT_CEILING_DIRECTORIES="$TRASH_ROOT/subdi"
 test_prefix subdir_ceil_at_subdi_slash "sub/dir/"
 
 
-GIT_CEILING_DIRECTORIES="/foo:$TRASH_ROOT/sub"
+GIT_CEILING_DIRECTORIES="/foo$PATH_SEP$TRASH_ROOT/sub"
 test_fail second_of_two
 
-GIT_CEILING_DIRECTORIES="$TRASH_ROOT/sub:/bar"
+GIT_CEILING_DIRECTORIES="$TRASH_ROOT/sub$PATH_SEP/bar"
 test_fail first_of_two
 
-GIT_CEILING_DIRECTORIES="/foo:$TRASH_ROOT/sub:/bar"
+GIT_CEILING_DIRECTORIES="/foo$PATH_SEP$TRASH_ROOT/sub$PATH_SEP/bar"
 test_fail second_of_three
 
 
diff --git a/t/t2300-cd-to-toplevel.sh b/t/t2300-cd-to-toplevel.sh
index b40eeb263fe896..4328b9172a5e6e 100755
--- a/t/t2300-cd-to-toplevel.sh
+++ b/t/t2300-cd-to-toplevel.sh
@@ -17,7 +17,7 @@ test_cd_to_toplevel () {
 	test_expect_success $3 "$2" '
 		(
 			cd '"'$1'"' &&
-			PATH="$EXEC_PATH:$PATH" &&
+			PATH="$EXEC_PATH$PATH_SEP$PATH" &&
 			. git-sh-setup &&
 			cd_to_toplevel &&
 			[ "$(pwd -P)" = "$TOPLEVEL" ]
diff --git a/t/t3418-rebase-continue.sh b/t/t3418-rebase-continue.sh
index c0d29c2154f0b4..b4d25f03435254 100755
--- a/t/t3418-rebase-continue.sh
+++ b/t/t3418-rebase-continue.sh
@@ -83,7 +83,7 @@ test_expect_success 'rebase --continue remembers merge strategy and options' '
 
 	rm -f actual &&
 	(
-		PATH=./test-bin:$PATH &&
+		PATH=./test-bin$PATH_SEP$PATH &&
 		test_must_fail git rebase -s funny -X"option=arg with space" \
 				-Xop\"tion\\ -X"new${LF}line " main topic
 	) &&
@@ -92,7 +92,7 @@ test_expect_success 'rebase --continue remembers merge strategy and options' '
 	echo "Resolved" >F2 &&
 	git add F2 &&
 	(
-		PATH=./test-bin:$PATH &&
+		PATH=./test-bin$PATH_SEP$PATH &&
 		git rebase --continue
 	) &&
 	test_cmp expect actual
diff --git a/t/t5615-alternate-env.sh b/t/t5615-alternate-env.sh
index 83513e46a3556b..fa2dd08084d21c 100755
--- a/t/t5615-alternate-env.sh
+++ b/t/t5615-alternate-env.sh
@@ -40,7 +40,7 @@ test_expect_success 'access alternate via absolute path' '
 '
 
 test_expect_success 'access multiple alternates' '
-	check_obj "$PWD/one.git/objects:$PWD/two.git/objects" <<-EOF
+	check_obj "$PWD/one.git/objects$PATH_SEP$PWD/two.git/objects" <<-EOF
 	$one blob
 	$two blob
 	EOF
@@ -76,7 +76,7 @@ test_expect_success 'access alternate via relative path (subdir)' '
 quoted='"one.git\057objects"'
 unquoted='two.git/objects'
 test_expect_success 'mix of quoted and unquoted alternates' '
-	check_obj "$quoted:$unquoted" <<-EOF
+	check_obj "$quoted$PATH_SEP$unquoted" <<-EOF
 	$one blob
 	$two blob
 	EOF
diff --git a/t/t5802-connect-helper.sh b/t/t5802-connect-helper.sh
index c6c2661878c0ca..a096eeeeb427cf 100755
--- a/t/t5802-connect-helper.sh
+++ b/t/t5802-connect-helper.sh
@@ -85,7 +85,7 @@ test_expect_success 'set up fake git-daemon' '
 		"$TRASH_DIRECTORY/remote"
 	EOF
 	export TRASH_DIRECTORY &&
-	PATH=$TRASH_DIRECTORY:$PATH
+	PATH=$TRASH_DIRECTORY$PATH_SEP$PATH
 '
 
 test_expect_success 'ext command can connect to git daemon (no vhost)' '
diff --git a/t/t7006-pager.sh b/t/t7006-pager.sh
index a0296d6ca4019e..6d9140fd90c368 100755
--- a/t/t7006-pager.sh
+++ b/t/t7006-pager.sh
@@ -55,7 +55,7 @@ test_expect_success !MINGW,TTY 'LESS and LV envvars set by git-sh-setup' '
 		sane_unset LESS LV &&
 		PAGER="env >pager-env.out; wc" &&
 		export PAGER &&
-		PATH="$(git --exec-path):$PATH" &&
+		PATH="$(git --exec-path)$PATH_SEP$PATH" &&
 		export PATH &&
 		test_terminal sh -c ". git-sh-setup && git_pager"
 	) &&
@@ -389,7 +389,7 @@ test_default_pager() {
 		EOF
 		chmod +x \$less &&
 		(
-			PATH=.:\$PATH &&
+			PATH=.$PATH_SEP\$PATH &&
 			export PATH &&
 			$full_command
 		) &&
diff --git a/t/t7606-merge-custom.sh b/t/t7606-merge-custom.sh
index 135cb230856533..c2c5f8a20c596d 100755
--- a/t/t7606-merge-custom.sh
+++ b/t/t7606-merge-custom.sh
@@ -24,7 +24,7 @@ test_expect_success 'set up custom strategy' '
 	EOF
 
 	chmod +x git-merge-theirs &&
-	PATH=.:$PATH &&
+	PATH=.$PATH_SEP$PATH &&
 	export PATH
 '
 
diff --git a/t/t7811-grep-open.sh b/t/t7811-grep-open.sh
index fe38d88a1a6ab1..e07a9eaae4662b 100755
--- a/t/t7811-grep-open.sh
+++ b/t/t7811-grep-open.sh
@@ -53,7 +53,7 @@ test_expect_success SIMPLEPAGER 'git grep -O' '
 	EOF
 	echo grep.h >expect.notless &&
 
-	PATH=.:$PATH git grep -O GREP_PATTERN >out &&
+	PATH=.$PATH_SEP$PATH git grep -O GREP_PATTERN >out &&
 	{
 		test_cmp expect.less pager-args ||
 		test_cmp expect.notless pager-args
diff --git a/t/t9003-help-autocorrect.sh b/t/t9003-help-autocorrect.sh
index 14a704d0a8c311..f32a4d0e5eeda7 100755
--- a/t/t9003-help-autocorrect.sh
+++ b/t/t9003-help-autocorrect.sh
@@ -14,7 +14,7 @@ test_expect_success 'setup' '
 		echo distimdistim was called
 	EOF
 
-	PATH="$PATH:." &&
+	PATH="$PATH$PATH_SEP." &&
 	export PATH &&
 
 	git commit --allow-empty -m "a single log entry" &&
diff --git a/t/t9800-git-p4-basic.sh b/t/t9800-git-p4-basic.sh
index 3e6dfce24833a0..cede9f5566f4cc 100755
--- a/t/t9800-git-p4-basic.sh
+++ b/t/t9800-git-p4-basic.sh
@@ -287,7 +287,7 @@ test_expect_success 'exit when p4 fails to produce marshaled output' '
 	EOF
 	chmod 755 badp4dir/p4 &&
 	(
-		PATH="$TRASH_DIRECTORY/badp4dir:$PATH" &&
+		PATH="$TRASH_DIRECTORY/badp4dir$PATH_SEP$PATH" &&
 		export PATH &&
 		test_expect_code 1 git p4 clone --dest="$git" //depot >errs 2>&1
 	) &&
diff --git a/t/test-lib.sh b/t/test-lib.sh
index c501acf7666044..84eba18020032a 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -15,6 +15,15 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see https://www.gnu.org/licenses/ .
 
+# On Unix/Linux, the path separator is the colon, on other systems it
+# may be different, though. On Windows, for example, it is a semicolon.
+# If the PATH variable contains semicolons, it is pretty safe to assume
+# that the path separator is a semicolon.
+case "$PATH" in
+*\;*) PATH_SEP=\; ;;
+*) PATH_SEP=: ;;
+esac
+
 # Test the binaries we have just built.  The tests are kept in
 # t/ subdirectory and are run in 'trash directory' subdirectory.
 if test -z "$TEST_DIRECTORY"
@@ -1462,7 +1471,7 @@ then
 		done
 	done
 	IFS=$OLDIFS
-	PATH=$GIT_VALGRIND/bin:$PATH
+	PATH=$GIT_VALGRIND/bin$PATH_SEP$PATH
 	GIT_EXEC_PATH=$GIT_VALGRIND/bin
 	export GIT_VALGRIND
 	GIT_VALGRIND_MODE="$valgrind"
@@ -1474,7 +1483,7 @@ elif test -n "$GIT_TEST_INSTALLED"
 then
 	GIT_EXEC_PATH=$($GIT_TEST_INSTALLED/git --exec-path)  ||
 	error "Cannot run git from $GIT_TEST_INSTALLED."
-	PATH=$GIT_TEST_INSTALLED:$GIT_BUILD_DIR/t/helper:$PATH
+	PATH=$GIT_TEST_INSTALLED$PATH_SEP$GIT_BUILD_DIR/t/helper$PATH_SEP$PATH
 	GIT_EXEC_PATH=${GIT_TEST_EXEC_PATH:-$GIT_EXEC_PATH}
 else # normal case, use ../bin-wrappers only unless $with_dashes:
 	if test -n "$no_bin_wrappers"
@@ -1490,12 +1499,12 @@ else # normal case, use ../bin-wrappers only unless $with_dashes:
 			fi
 			with_dashes=t
 		fi
-		PATH="$git_bin_dir:$PATH"
+		PATH="$git_bin_dir$PATH_SEP$PATH"
 	fi
 	GIT_EXEC_PATH=$GIT_BUILD_DIR
 	if test -n "$with_dashes"
 	then
-		PATH="$GIT_BUILD_DIR:$GIT_BUILD_DIR/t/helper:$PATH"
+		PATH="$GIT_BUILD_DIR$PATH_SEP$GIT_BUILD_DIR/t/helper$PATH_SEP$PATH"
 	fi
 fi
 GIT_TEMPLATE_DIR="$GIT_BUILD_DIR"/templates/blt

From ec5232f9ce8b2a62b212fa5c4c64bdbdd5698ed5 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 30 Jun 2017 00:35:40 +0200
Subject: [PATCH 233/259] mingw: only use Bash-ism `builtin pwd -W` when
 available

Traditionally, Git for Windows' SDK uses Bash as its default shell.
However, other Unix shells are available, too. Most notably, the Win32
port of BusyBox comes with `ash` whose `pwd` command already prints
Windows paths as Git for Windows wants them, while there is not even a
`builtin` command.

Therefore, let's be careful not to override `pwd` unless we know that
the `builtin` command is available.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 git-sh-setup.sh | 14 ++++++++++----
 t/test-lib.sh   | 14 ++++++++++----
 2 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/git-sh-setup.sh b/git-sh-setup.sh
index 785a4cbfa9c65e..b53539cd0e556a 100644
--- a/git-sh-setup.sh
+++ b/git-sh-setup.sh
@@ -306,10 +306,16 @@ case $(uname -s) in
 			/usr/bin/find "$@"
 		}
 	fi
-	# git sees Windows-style pwd
-	pwd () {
-		builtin pwd -W
-	}
+	# On Windows, Git wants Windows paths. But /usr/bin/pwd spits out
+	# Unix-style paths. At least in Bash, we have a builtin pwd that
+	# understands the -W option to force "mixed" paths, i.e. with drive
+	# prefix but still with forward slashes. Let's use that, if available.
+	if type builtin >/dev/null 2>&1
+	then
+		pwd () {
+			builtin pwd -W
+		}
+	fi
 	is_absolute_path () {
 		case "$1" in
 		[/\\]* | [A-Za-z]:*)
diff --git a/t/test-lib.sh b/t/test-lib.sh
index 84eba18020032a..68280ae0e4cbfe 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -1724,10 +1724,16 @@ case $uname_s in
 			/usr/bin/find "$@"
 		}
 	fi
-	# git sees Windows-style pwd
-	pwd () {
-		builtin pwd -W
-	}
+	# On Windows, Git wants Windows paths. But /usr/bin/pwd spits out
+	# Unix-style paths. At least in Bash, we have a builtin pwd that
+	# understands the -W option to force "mixed" paths, i.e. with drive
+	# prefix but still with forward slashes. Let's use that, if available.
+	if type builtin >/dev/null 2>&1
+	then
+		pwd () {
+			builtin pwd -W
+		}
+	fi
 	# no POSIX permissions
 	# backslashes in pathspec are converted to '/'
 	# exec does not inherit the PID

From 91d1456caeec8aab6c0bb49f157e841aa7638337 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 30 Jun 2017 22:32:33 +0200
Subject: [PATCH 234/259] tests (mingw): remove Bash-specific pwd option

The -W option is only understood by MSYS2 Bash's pwd command. We already
make sure to override `pwd` by `builtin pwd -W` for MINGW, so let's not
double the effort here.

This will also help when switching the shell to another one (such as
BusyBox' ash) whose pwd does *not* understand the -W option.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t9902-completion.sh | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/t/t9902-completion.sh b/t/t9902-completion.sh
index 932d5ad7591698..f225313ab3963e 100755
--- a/t/t9902-completion.sh
+++ b/t/t9902-completion.sh
@@ -139,12 +139,7 @@ invalid_variable_name='${foo.bar}'
 
 actual="$TRASH_DIRECTORY/actual"
 
-if test_have_prereq MINGW
-then
-	ROOT="$(pwd -W)"
-else
-	ROOT="$(pwd)"
-fi
+ROOT="$(pwd)"
 
 test_expect_success 'setup for __git_find_repo_path/__gitdir tests' '
 	mkdir -p subdir/subsubdir &&

From 3d148a6302c2bdc1ef4e91b9469ac2a16710dfbb Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 19 Jul 2017 17:07:56 +0200
Subject: [PATCH 235/259] test-lib: add BUSYBOX prerequisite

When running with BusyBox, we will want to avoid calling executables on
the PATH that are implemented in BusyBox itself.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/test-lib.sh | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/t/test-lib.sh b/t/test-lib.sh
index 68280ae0e4cbfe..8604e1486a1691 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -1915,6 +1915,10 @@ test_lazy_prereq UNZIP '
 	test $? -ne 127
 '
 
+test_lazy_prereq BUSYBOX '
+	case "$($SHELL --help 2>&1)" in *BusyBox*) true;; *) false;; esac
+'
+
 run_with_limited_cmdline () {
 	(ulimit -s 128 && "$@")
 }

From c282e1d4583bdda931382b70710eb3683c1e600a Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sat, 5 Aug 2017 21:36:01 +0200
Subject: [PATCH 236/259] t5003: use binary file from t/lib-diff/

At some stage, t5003-archive-zip wants to add a file that is not ASCII.
To that end, it uses /bin/sh. But that file may actually not exist (it
is too easy to forget that not all the world is Unix/Linux...)! Besides,
we already have perfectly fine binary files intended for use solely by
the tests. So let's use one of them instead.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t5003-archive-zip.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/t/t5003-archive-zip.sh b/t/t5003-archive-zip.sh
index 961c6aac256135..2c3d5a13ad027f 100755
--- a/t/t5003-archive-zip.sh
+++ b/t/t5003-archive-zip.sh
@@ -88,7 +88,7 @@ test_expect_success \
     'mkdir a &&
      echo simple textfile >a/a &&
      mkdir a/bin &&
-     cp /bin/sh a/bin &&
+     cp "$TEST_DIRECTORY/lib-diff/test-binary-1.png" a/bin &&
      printf "text\r"	>a/text.cr &&
      printf "text\r\n"	>a/text.crlf &&
      printf "text\n"	>a/text.lf &&

From 1faeaf09d5e0283577b11a568d415ba92afb2dd1 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 21 Jul 2017 12:48:33 +0200
Subject: [PATCH 237/259] t5532: workaround for BusyBox on Windows

While it may seem super convenient to some old Unix hands to simpy
require Perl to be available when running the test suite, this is a
major hassle on Windows, where we want to verify that Perl is not,
actually, required in a NO_PERL build.

As a super ugly workaround, we "install" a script into /usr/bin/perl
reading like this:

	#!/bin/sh

	# We'd much rather avoid requiring Perl altogether when testing
	# an installed Git. Oh well, that's why we cannot have nice
	# things.
	exec c:/git-sdk-64/usr/bin/perl.exe "$@"

The problem with that is that BusyBox assumes that the #! line in a
script refers to an executable, not to a script. So when it encounters
the line #!/usr/bin/perl in t5532's proxy-get-cmd, it barfs.

Let's help this situation by simply executing the Perl script with the
"interpreter" specified explicitly.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t5532-fetch-proxy.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/t/t5532-fetch-proxy.sh b/t/t5532-fetch-proxy.sh
index d664912799b43a..55bc57c138ddc2 100755
--- a/t/t5532-fetch-proxy.sh
+++ b/t/t5532-fetch-proxy.sh
@@ -27,7 +27,7 @@ test_expect_success 'setup proxy script' '
 
 	write_script proxy <<-\EOF
 	echo >&2 "proxying for $*"
-	cmd=$(./proxy-get-cmd)
+	cmd=$("$PERL_PATH" ./proxy-get-cmd)
 	echo >&2 "Running $cmd"
 	exec $cmd
 	EOF

From 4623aee38dad83a1c17efee4064948380f6c8736 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 21 Jul 2017 13:24:55 +0200
Subject: [PATCH 238/259] t5605: special-case hardlink test for BusyBox-w32

When t5605 tries to verify that files are hardlinked (or that they are
not), it uses the `-links` option of the `find` utility.

BusyBox' implementation does not support that option, and BusyBox-w32's
lstat() does not even report the number of hard links correctly (for
performance reasons).

So let's just switch to a different method that actually works on
Windows.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t5605-clone-local.sh | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/t/t5605-clone-local.sh b/t/t5605-clone-local.sh
index d9a320abd21657..ed9bfb5e44a42e 100755
--- a/t/t5605-clone-local.sh
+++ b/t/t5605-clone-local.sh
@@ -12,6 +12,21 @@ repo_is_hardlinked() {
 	test_line_count = 0 output
 }
 
+if test_have_prereq MINGW,BUSYBOX
+then
+	# BusyBox' `find` does not support `-links`. Besides, BusyBox-w32's
+	# lstat() does not report hard links, just like Git's mingw_lstat()
+	# (from where BusyBox-w32 got its initial implementation).
+	repo_is_hardlinked() {
+		for f in $(find "$1/objects" -type f)
+		do
+			"$SYSTEMROOT"/system32/fsutil.exe \
+				hardlink list $f >links &&
+			test_line_count -gt 1 links || return 1
+		done
+	}
+fi
+
 test_expect_success 'preparing origin repository' '
 	: >file && git add . && git commit -m1 &&
 	git clone --bare . a.git &&

From b0095e8c20fbbe694f796e2c6787a5cde2dcaa25 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 5 Jul 2017 15:14:50 +0200
Subject: [PATCH 239/259] t5813: allow for $PWD to be a Windows path

Git for Windows uses MSYS2's Bash to run the test suite, which comes
with benefits but also at a heavy price: on the plus side, MSYS2's
POSIX emulation layer allows us to continue pretending that we are on a
Unix system, e.g. use Unix paths instead of Windows ones, yet this is
bought at a rather noticeable performance penalty.

There *are* some more native ports of Unix shells out there, though,
most notably BusyBox-w32's ash. These native ports do not use any POSIX
emulation layer (or at most a *very* thin one, choosing to avoid
features such as fork() that are expensive to emulate on Windows), and
they use native Windows paths (usually with forward slashes instead of
backslashes, which is perfectly legal in almost all use cases).

And here comes the problem: with a $PWD looking like, say,
C:/git-sdk-64/usr/src/git/t/trash directory.t5813-proto-disable-ssh
Git's test scripts get quite a bit confused, as their assumptions have
been shattered. Not only does this path contain a colon (oh no!), it
also does not start with a slash.

This is a problem e.g. when constructing a URL as t5813 does it:
ssh://remote$PWD. Not only is it impossible to separate the "host" from
the path with a $PWD as above, even prefixing $PWD by a slash won't
work, as /C:/git-sdk-64/... is not a valid path.

As a workaround, detect when $PWD does not start with a slash on
Windows, and simply strip the drive prefix, using an obscure feature of
Windows paths: if an absolute Windows path starts with a slash, it is
implicitly prefixed by the drive prefix of the current directory. As we
are talking about the current directory here, anyway, that strategy
works.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t5813-proto-disable-ssh.sh | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/t/t5813-proto-disable-ssh.sh b/t/t5813-proto-disable-ssh.sh
index 2e975dc70ec2c8..9e84f83f2dd100 100755
--- a/t/t5813-proto-disable-ssh.sh
+++ b/t/t5813-proto-disable-ssh.sh
@@ -16,8 +16,23 @@ test_expect_success 'setup repository to clone' '
 '
 
 test_proto "host:path" ssh "remote:repo.git"
-test_proto "ssh://" ssh "ssh://remote$PWD/remote/repo.git"
-test_proto "git+ssh://" ssh "git+ssh://remote$PWD/remote/repo.git"
+
+hostdir="$PWD"
+if test_have_prereq MINGW && test "/${PWD#/}" != "$PWD"
+then
+	case "$PWD" in
+	[A-Za-z]:/*)
+		hostdir="${PWD#?:}"
+		;;
+	*)
+		skip_all="Unhandled PWD '$PWD'; skipping rest"
+		test_done
+		;;
+	esac
+fi
+
+test_proto "ssh://" ssh "ssh://remote$hostdir/remote/repo.git"
+test_proto "git+ssh://" ssh "git+ssh://remote$hostdir/remote/repo.git"
 
 # Don't even bother setting up a "-remote" directory, as ssh would generally
 # complain about the bogus option rather than completing our request. Our

From 401cb93e667a03ea6919f7778db2aaccdcaa1874 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 7 Jul 2017 10:15:36 +0200
Subject: [PATCH 240/259] t9200: skip tests when $PWD contains a colon

On Windows, the current working directory is pretty much guaranteed to
contain a colon. If we feed that path to CVS, it mistakes it for a
separator between host and port, though.

This has not been a problem so far because Git for Windows uses MSYS2's
Bash using a POSIX emulation layer that also pretends that the current
directory is a Unix path (at least as long as we're in a shell script).

However, that is rather limiting, as Git for Windows also explores other
ports of other Unix shells. One of those is BusyBox-w32's ash, which is
a native port (i.e. *not* using any POSIX emulation layer, and certainly
not emulating Unix paths).

So let's just detect if there is a colon in $PWD and punt in that case.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t9200-git-cvsexportcommit.sh | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/t/t9200-git-cvsexportcommit.sh b/t/t9200-git-cvsexportcommit.sh
index 3dc8d77433f6ea..65aea65b55517f 100755
--- a/t/t9200-git-cvsexportcommit.sh
+++ b/t/t9200-git-cvsexportcommit.sh
@@ -12,6 +12,13 @@ if ! test_have_prereq PERL; then
 	test_done
 fi
 
+case "$PWD" in
+*:*)
+	skip_all='cvs would get confused by the colon in `pwd`; skipping tests'
+	test_done
+	;;
+esac
+
 cvs >/dev/null 2>&1
 if test $? -ne 1
 then

From a3a2b32a4389e1caee7359c9abe948d44f5c8641 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 17 May 2017 17:05:09 +0200
Subject: [PATCH 241/259] mingw: kill child processes in a gentler way

The TerminateProcess() function does not actually leave the child
processes any chance to perform any cleanup operations. This is bad
insofar as Git itself expects its signal handlers to run.

A symptom is e.g. a left-behind .lock file that would not be left behind
if the same operation was run, say, on Linux.

To remedy this situation, we use an obscure trick: we inject a thread
into the process that needs to be killed and to let that thread run the
ExitProcess() function with the desired exit status. Thanks J Wyman for
describing this trick.

The advantage is that the ExitProcess() function lets the atexit
handlers run. While this is still different from what Git expects (i.e.
running a signal handler), in practice Git sets up signal handlers and
atexit handlers that call the same code to clean up after itself.

In case that the gentle method to terminate the process failed, we still
fall back to calling TerminateProcess(), but in that case we now also
make sure that processes spawned by the spawned process are terminated;
TerminateProcess() does not give the spawned process a chance to do so
itself.

Please note that this change only affects how Git for Windows tries to
terminate processes spawned by Git's own executables. Third-party
software that *calls* Git and wants to terminate it *still* need to make
sure to imitate this gentle method, otherwise this patch will not have
any effect.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c              |  29 +++++--
 compat/win32/exit-process.h | 165 ++++++++++++++++++++++++++++++++++++
 2 files changed, 186 insertions(+), 8 deletions(-)
 create mode 100644 compat/win32/exit-process.h

diff --git a/compat/mingw.c b/compat/mingw.c
index 4626f98e522058..2a57def36b1af6 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -10,6 +10,7 @@
 #include "../run-command.h"
 #include "../abspath.h"
 #include "../alloc.h"
+#include "win32/exit-process.h"
 #include "win32/lazyload.h"
 #include "../config.h"
 #include "../environment.h"
@@ -2213,16 +2214,28 @@ int mingw_execvp(const char *cmd, char *const *argv)
 int mingw_kill(pid_t pid, int sig)
 {
 	if (pid > 0 && sig == SIGTERM) {
-		HANDLE h = OpenProcess(PROCESS_TERMINATE, FALSE, pid);
-
-		if (TerminateProcess(h, -1)) {
+		HANDLE h = OpenProcess(PROCESS_CREATE_THREAD |
+				       PROCESS_QUERY_INFORMATION |
+				       PROCESS_VM_OPERATION | PROCESS_VM_WRITE |
+				       PROCESS_VM_READ | PROCESS_TERMINATE,
+				       FALSE, pid);
+		int ret;
+
+		if (h)
+			ret = exit_process(h, 128 + sig);
+		else {
+			h = OpenProcess(PROCESS_TERMINATE, FALSE, pid);
+			if (!h) {
+				errno = err_win_to_posix(GetLastError());
+				return -1;
+			}
+			ret = terminate_process_tree(h, 128 + sig);
+		}
+		if (ret) {
+			errno = err_win_to_posix(GetLastError());
 			CloseHandle(h);
-			return 0;
 		}
-
-		errno = err_win_to_posix(GetLastError());
-		CloseHandle(h);
-		return -1;
+		return ret;
 	} else if (pid > 0 && sig == 0) {
 		HANDLE h = OpenProcess(PROCESS_QUERY_INFORMATION, FALSE, pid);
 		if (h) {
diff --git a/compat/win32/exit-process.h b/compat/win32/exit-process.h
new file mode 100644
index 00000000000000..d53989884cfb0c
--- /dev/null
+++ b/compat/win32/exit-process.h
@@ -0,0 +1,165 @@
+#ifndef EXIT_PROCESS_H
+#define EXIT_PROCESS_H
+
+/*
+ * This file contains functions to terminate a Win32 process, as gently as
+ * possible.
+ *
+ * At first, we will attempt to inject a thread that calls ExitProcess(). If
+ * that fails, we will fall back to terminating the entire process tree.
+ *
+ * For simplicity, these functions are marked as file-local.
+ */
+
+#include <tlhelp32.h>
+
+/*
+ * Terminates the process corresponding to the process ID and all of its
+ * directly and indirectly spawned subprocesses.
+ *
+ * This way of terminating the processes is not gentle: the processes get
+ * no chance of cleaning up after themselves (closing file handles, removing
+ * .lock files, terminating spawned processes (if any), etc).
+ */
+static int terminate_process_tree(HANDLE main_process, int exit_status)
+{
+	HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
+	PROCESSENTRY32 entry;
+	DWORD pids[16384];
+	int max_len = sizeof(pids) / sizeof(*pids), i, len, ret = 0;
+	pid_t pid = GetProcessId(main_process);
+
+	pids[0] = (DWORD)pid;
+	len = 1;
+
+	/*
+	 * Even if Process32First()/Process32Next() seem to traverse the
+	 * processes in topological order (i.e. parent processes before
+	 * child processes), there is nothing in the Win32 API documentation
+	 * suggesting that this is guaranteed.
+	 *
+	 * Therefore, run through them at least twice and stop when no more
+	 * process IDs were added to the list.
+	 */
+	for (;;) {
+		int orig_len = len;
+
+		memset(&entry, 0, sizeof(entry));
+		entry.dwSize = sizeof(entry);
+
+		if (!Process32First(snapshot, &entry))
+			break;
+
+		do {
+			for (i = len - 1; i >= 0; i--) {
+				if (pids[i] == entry.th32ProcessID)
+					break;
+				if (pids[i] == entry.th32ParentProcessID)
+					pids[len++] = entry.th32ProcessID;
+			}
+		} while (len < max_len && Process32Next(snapshot, &entry));
+
+		if (orig_len == len || len >= max_len)
+			break;
+	}
+
+	for (i = len - 1; i > 0; i--) {
+		HANDLE process = OpenProcess(PROCESS_TERMINATE, FALSE, pids[i]);
+
+		if (process) {
+			if (!TerminateProcess(process, exit_status))
+				ret = -1;
+			CloseHandle(process);
+		}
+	}
+	if (!TerminateProcess(main_process, exit_status))
+		ret = -1;
+	CloseHandle(main_process);
+
+	return ret;
+}
+
+/**
+ * Determine whether a process runs in the same architecture as the current
+ * one. That test is required before we assume that GetProcAddress() returns
+ * a valid address *for the target process*.
+ */
+static inline int process_architecture_matches_current(HANDLE process)
+{
+	static BOOL current_is_wow = -1;
+	BOOL is_wow;
+
+	if (current_is_wow == -1 &&
+	    !IsWow64Process (GetCurrentProcess(), &current_is_wow))
+		current_is_wow = -2;
+	if (current_is_wow == -2)
+		return 0; /* could not determine current process' WoW-ness */
+	if (!IsWow64Process (process, &is_wow))
+		return 0; /* cannot determine */
+	return is_wow == current_is_wow;
+}
+
+/**
+ * Inject a thread into the given process that runs ExitProcess().
+ *
+ * Note: as kernel32.dll is loaded before any process, the other process and
+ * this process will have ExitProcess() at the same address.
+ *
+ * This function expects the process handle to have the access rights for
+ * CreateRemoteThread(): PROCESS_CREATE_THREAD, PROCESS_QUERY_INFORMATION,
+ * PROCESS_VM_OPERATION, PROCESS_VM_WRITE, and PROCESS_VM_READ.
+ *
+ * The idea comes from the Dr Dobb's article "A Safer Alternative to
+ * TerminateProcess()" by Andrew Tucker (July 1, 1999),
+ * http://www.drdobbs.com/a-safer-alternative-to-terminateprocess/184416547
+ *
+ * If this method fails, we fall back to running terminate_process_tree().
+ */
+static int exit_process(HANDLE process, int exit_code)
+{
+	DWORD code;
+
+	if (GetExitCodeProcess(process, &code) && code == STILL_ACTIVE) {
+		static int initialized;
+		static LPTHREAD_START_ROUTINE exit_process_address;
+		PVOID arg = (PVOID)(intptr_t)exit_code;
+		DWORD thread_id;
+		HANDLE thread = NULL;
+
+		if (!initialized) {
+			HINSTANCE kernel32 = GetModuleHandleA("kernel32");
+			if (!kernel32)
+				die("BUG: cannot find kernel32");
+			exit_process_address =
+				(LPTHREAD_START_ROUTINE)(void (*)(void))
+				GetProcAddress(kernel32, "ExitProcess");
+			initialized = 1;
+		}
+		if (!exit_process_address ||
+		    !process_architecture_matches_current(process))
+			return terminate_process_tree(process, exit_code);
+
+		thread = CreateRemoteThread(process, NULL, 0,
+					    exit_process_address,
+					    arg, 0, &thread_id);
+		if (thread) {
+			CloseHandle(thread);
+			/*
+			 * If the process survives for 10 seconds (a completely
+			 * arbitrary value picked from thin air), fall back to
+			 * killing the process tree via TerminateProcess().
+			 */
+			if (WaitForSingleObject(process, 10000) ==
+			    WAIT_OBJECT_0) {
+				CloseHandle(process);
+				return 0;
+			}
+		}
+
+		return terminate_process_tree(process, exit_code);
+	}
+
+	return 0;
+}
+
+#endif

From bdf7fec0ed6897e06e3de897996d878795b040ba Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 20 Jul 2017 00:23:26 +0200
Subject: [PATCH 242/259] mingw: add a Makefile target to copy test artifacts

The Makefile target `install-mingit-test-artifacts` simply copies stuff
and things directly into a MinGit directory, including an init.bat
script to set everything up so that the tests can be run in a cmd
window.

Sadly, Git's test suite still relies on a Perl interpreter even if
compiled with NO_PERL=YesPlease. We punt for now, installing a small
script into /usr/bin/perl that hands off to an existing Perl of a Git
for Windows SDK.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 config.mak.uname | 56 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)

diff --git a/config.mak.uname b/config.mak.uname
index 937646d8079c38..fb0497b0270d51 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -754,6 +754,62 @@ ifeq ($(uname_S),MINGW)
 		ETC_GITCONFIG = ../etc/gitconfig
 		ETC_GITATTRIBUTES = ../etc/gitattributes
         endif
+ifeq (i686,$(uname_M))
+	MINGW_PREFIX := mingw32
+endif
+ifeq (x86_64,$(uname_M))
+	MINGW_PREFIX := mingw64
+endif
+
+	DESTDIR_WINDOWS = $(shell cygpath -aw '$(DESTDIR_SQ)')
+	DESTDIR_MIXED = $(shell cygpath -am '$(DESTDIR_SQ)')
+install-mingit-test-artifacts:
+	install -m755 -d '$(DESTDIR_SQ)/usr/bin'
+	printf '%s\n%s\n' >'$(DESTDIR_SQ)/usr/bin/perl' \
+		"#!/mingw64/bin/busybox sh" \
+		"exec \"$(shell cygpath -am /usr/bin/perl.exe)\" \"\$$@\""
+
+	install -m755 -d '$(DESTDIR_SQ)'
+	printf '%s%s\n%s\n%s\n%s\n%s\n' >'$(DESTDIR_SQ)/init.bat' \
+		"PATH=$(DESTDIR_WINDOWS)\\$(MINGW_PREFIX)\\bin;" \
+		"C:\\WINDOWS;C:\\WINDOWS\\system32" \
+		"@set GIT_TEST_INSTALLED=$(DESTDIR_MIXED)/$(MINGW_PREFIX)/bin" \
+		"@`echo "$(DESTDIR_WINDOWS)" | sed 's/:.*/:/'`" \
+		"@cd `echo "$(DESTDIR_WINDOWS)" | sed 's/^.://'`\\test-git\\t" \
+		"@echo Now, run 'helper\\test-run-command testsuite'"
+
+	install -m755 -d '$(DESTDIR_SQ)/test-git'
+	sed 's/^\(NO_PERL\|NO_PYTHON\)=.*/\1=YesPlease/' \
+		<GIT-BUILD-OPTIONS >'$(DESTDIR_SQ)/test-git/GIT-BUILD-OPTIONS'
+
+	install -m755 -d '$(DESTDIR_SQ)/test-git/t/helper'
+	install -m755 $(TEST_PROGRAMS) '$(DESTDIR_SQ)/test-git/t/helper'
+	(cd t && $(TAR) cf - t[0-9][0-9][0-9][0-9] lib-diff) | \
+	(cd '$(DESTDIR_SQ)/test-git/t' && $(TAR) xf -)
+	install -m755 t/t556x_common t/*.sh '$(DESTDIR_SQ)/test-git/t'
+
+	install -m755 -d '$(DESTDIR_SQ)/test-git/templates'
+	(cd templates && $(TAR) cf - blt) | \
+	(cd '$(DESTDIR_SQ)/test-git/templates' && $(TAR) xf -)
+
+	# po/build/locale for t0200
+	install -m755 -d '$(DESTDIR_SQ)/test-git/po/build/locale'
+	(cd po/build/locale && $(TAR) cf - .) | \
+	(cd '$(DESTDIR_SQ)/test-git/po/build/locale' && $(TAR) xf -)
+
+	# git-daemon.exe for t5802, git-http-backend.exe for t5560
+	install -m755 -d '$(DESTDIR_SQ)/$(MINGW_PREFIX)/bin'
+	install -m755 git-daemon.exe git-http-backend.exe \
+		'$(DESTDIR_SQ)/$(MINGW_PREFIX)/bin'
+
+	# git-upload-archive (dashed) for t5000
+	install -m755 -d '$(DESTDIR_SQ)/$(MINGW_PREFIX)/bin'
+	install -m755 git-upload-archive.exe '$(DESTDIR_SQ)/$(MINGW_PREFIX)/bin'
+
+	# git-difftool--helper for t7800
+	install -m755 -d '$(DESTDIR_SQ)/$(MINGW_PREFIX)/libexec/git-core'
+	install -m755 git-difftool--helper \
+		'$(DESTDIR_SQ)/$(MINGW_PREFIX)/libexec/git-core'
 endif
 ifeq ($(uname_S),QNX)
 	COMPAT_CFLAGS += -DSA_RESTART=0

From 703d0daa38bbd640f743b21776cf1e5801603f14 Mon Sep 17 00:00:00 2001
From: xungeng li <xungeng@gmail.com>
Date: Wed, 7 Jun 2023 20:26:33 +0800
Subject: [PATCH 243/259] mingw: optionally enable wsl compability file mode
 bits

The Windows Subsystem for Linux (WSL) version 2 allows to use `chmod` on
NTFS volumes provided that they are mounted with metadata enabled (see
https://devblogs.microsoft.com/commandline/chmod-chown-wsl-improvements/
for details), for example:

	$ chmod 0755 /mnt/d/test/a.sh

In order to facilitate better collaboration between the Windows
version of Git and the WSL version of Git, we can make the Windows
version of Git also support reading and writing NTFS file modes
in a manner compatible with WSL.

Since this slightly slows down operations where lots of files are
created (such as an initial checkout), this feature is only enabled when
`core.WSLCompat` is set to true. Note that you also have to set
`core.fileMode=true` in repositories that have been initialized without
enabling WSL compatibility.

There are several ways to enable metadata loading for NTFS volumes
in WSL, one of which is to modify `/etc/wsl.conf` by adding:

```
[automount]
enabled = true
options = "metadata,umask=027,fmask=117"
```

And reboot WSL.

It can also be enabled temporarily by this incantation:

	$ sudo umount /mnt/c &&
	  sudo mount -t drvfs C: /mnt/c -o metadata,uid=1000,gid=1000,umask=22,fmask=111

It's important to note that this modification is compatible with, but
does not depend on WSL. The helper functions in this commit can operate
independently and functions normally on devices where WSL is not
installed or properly configured.

Signed-off-by: xungeng li <xungeng@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 Documentation/config/core.txt       |   6 ++
 compat/mingw.c                      |  13 +++
 compat/win32/fscache.c              |  16 ++++
 compat/win32/wsl.c                  | 142 ++++++++++++++++++++++++++++
 compat/win32/wsl.h                  |  12 +++
 config.mak.uname                    |   4 +-
 contrib/buildsystems/CMakeLists.txt |   1 +
 7 files changed, 192 insertions(+), 2 deletions(-)
 create mode 100644 compat/win32/wsl.c
 create mode 100644 compat/win32/wsl.h

diff --git a/Documentation/config/core.txt b/Documentation/config/core.txt
index 55c8939452a7a4..458a3f4f7f5d80 100644
--- a/Documentation/config/core.txt
+++ b/Documentation/config/core.txt
@@ -771,3 +771,9 @@ core.maxTreeDepth::
 	to allow Git to abort cleanly, and should not generally need to
 	be adjusted. When Git is compiled with MSVC, the default is 512.
 	Otherwise, the default is 2048.
+
+core.WSLCompat::
+	Tells Git whether to enable wsl compatibility mode.
+	The default value is false. When set to true, Git will set the mode
+	bits of the file in the way of wsl, so that the executable flag of
+	files can be set or read correctly.
diff --git a/compat/mingw.c b/compat/mingw.c
index e61981cdaafa10..6e29111f73486a 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -25,6 +25,7 @@
 #include "win32/fscache.h"
 #include "../attr.h"
 #include "../string-list.h"
+#include "win32/wsl.h"
 
 #define HCAST(type, handle) ((type)(intptr_t)handle)
 
@@ -811,6 +812,11 @@ int mingw_open (const char *filename, int oflags, ...)
 
 	fd = open_fn(wfilename, oflags, mode);
 
+	if ((oflags & O_CREAT) && fd >= 0 && are_wsl_compatible_mode_bits_enabled()) {
+		_mode_t wsl_mode = S_IFREG | (mode&0777);
+		set_wsl_mode_bits_by_handle((HANDLE)_get_osfhandle(fd), wsl_mode);
+	}
+
 	if (fd < 0 && (oflags & O_ACCMODE) != O_RDONLY && errno == EACCES) {
 		DWORD attrs = GetFileAttributesW(wfilename);
 		if (attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY))
@@ -1110,6 +1116,11 @@ int mingw_lstat(const char *file_name, struct stat *buf)
 		filetime_to_timespec(&(fdata.ftLastAccessTime), &(buf->st_atim));
 		filetime_to_timespec(&(fdata.ftLastWriteTime), &(buf->st_mtim));
 		filetime_to_timespec(&(fdata.ftCreationTime), &(buf->st_ctim));
+		if (S_ISREG(buf->st_mode) &&
+		    are_wsl_compatible_mode_bits_enabled()) {
+			copy_wsl_mode_bits_from_disk(wfilename, -1,
+						     &buf->st_mode);
+		}
 		return 0;
 	}
 
@@ -1161,6 +1172,8 @@ static int get_file_info_by_handle(HANDLE hnd, struct stat *buf)
 	filetime_to_timespec(&(fdata.ftLastAccessTime), &(buf->st_atim));
 	filetime_to_timespec(&(fdata.ftLastWriteTime), &(buf->st_mtim));
 	filetime_to_timespec(&(fdata.ftCreationTime), &(buf->st_ctim));
+	if (are_wsl_compatible_mode_bits_enabled())
+	    get_wsl_mode_bits_by_handle(hnd, &buf->st_mode);
 	return 0;
 }
 
diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index d3819aa7f86466..a4f85ac9b77be2 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -8,6 +8,7 @@
 #include "config.h"
 #include "../../mem-pool.h"
 #include "ntifs.h"
+#include "wsl.h"
 
 static volatile long initialized;
 static DWORD dwTlsIndex;
@@ -215,6 +216,21 @@ static struct fsentry *fseentry_create_entry(struct fscache *cache,
 			     &(fse->u.s.st_mtim));
 	filetime_to_timespec((FILETIME *)&(fdata->CreationTime),
 			     &(fse->u.s.st_ctim));
+	if (fdata->EaSize > 0 &&
+	    sizeof(buf) >= (list ? list->len+1 : 0) + fse->len+1 &&
+	    are_wsl_compatible_mode_bits_enabled()) {
+		size_t off = 0;
+		wchar_t wpath[MAX_LONG_PATH];
+		if (list && list->len) {
+			memcpy(buf, list->dirent.d_name, list->len);
+			buf[list->len] = '/';
+			off = list->len + 1;
+		}
+		memcpy(buf + off, fse->dirent.d_name, fse->len);
+		buf[off + fse->len] = '\0';
+		if (xutftowcs_long_path(wpath, buf) >= 0)
+			copy_wsl_mode_bits_from_disk(wpath, -1, &fse->st_mode);
+	}
 
 	return fse;
 }
diff --git a/compat/win32/wsl.c b/compat/win32/wsl.c
new file mode 100644
index 00000000000000..c6e9f3bfeacb84
--- /dev/null
+++ b/compat/win32/wsl.c
@@ -0,0 +1,142 @@
+#define USE_THE_REPOSITORY_VARIABLE
+#include "../../git-compat-util.h"
+#include "../win32.h"
+#include "../../repository.h"
+#include "config.h"
+#include "ntifs.h"
+#include "wsl.h"
+
+int are_wsl_compatible_mode_bits_enabled(void)
+{
+	/* default to `false` during initialization */
+	static const int fallback = 0;
+	static int enabled = -1;
+
+	if (enabled < 0) {
+		/* avoid infinite recursion */
+		if (!the_repository)
+			return fallback;
+
+		if (the_repository->config &&
+		    the_repository->config->hash_initialized &&
+		    git_config_get_bool("core.wslcompat", &enabled) < 0)
+			enabled = 0;
+	}
+
+	return enabled < 0 ? fallback : enabled;
+}
+
+int copy_wsl_mode_bits_from_disk(const wchar_t *wpath, ssize_t wpathlen,
+				 _mode_t *mode)
+{
+	int ret = -1;
+	HANDLE h;
+	if (wpathlen >= 0) {
+		/*
+		 * It's caller's duty to make sure wpathlen is reasonable so
+		 * it does not overflow.
+		 */
+		wchar_t *fn2 = (wchar_t*)alloca((wpathlen + 1) * sizeof(wchar_t));
+		memcpy(fn2, wpath, wpathlen * sizeof(wchar_t));
+		fn2[wpathlen] = 0;
+		wpath = fn2;
+	}
+	h = CreateFileW(wpath, FILE_READ_EA | SYNCHRONIZE,
+			FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
+			NULL, OPEN_EXISTING,
+			FILE_FLAG_BACKUP_SEMANTICS |
+				FILE_FLAG_OPEN_REPARSE_POINT,
+			NULL);
+	if (h != INVALID_HANDLE_VALUE) {
+		ret = get_wsl_mode_bits_by_handle(h, mode);
+		CloseHandle(h);
+	}
+	return ret;
+}
+
+#ifndef LX_FILE_METADATA_HAS_UID
+#define LX_FILE_METADATA_HAS_UID 0x1
+#define LX_FILE_METADATA_HAS_GID 0x2
+#define LX_FILE_METADATA_HAS_MODE 0x4
+#define LX_FILE_METADATA_HAS_DEVICE_ID 0x8
+#define LX_FILE_CASE_SENSITIVE_DIR 0x10
+typedef struct _FILE_STAT_LX_INFORMATION {
+	LARGE_INTEGER FileId;
+	LARGE_INTEGER CreationTime;
+	LARGE_INTEGER LastAccessTime;
+	LARGE_INTEGER LastWriteTime;
+	LARGE_INTEGER ChangeTime;
+	LARGE_INTEGER AllocationSize;
+	LARGE_INTEGER EndOfFile;
+	uint32_t FileAttributes;
+	uint32_t ReparseTag;
+	uint32_t NumberOfLinks;
+	ACCESS_MASK EffectiveAccess;
+	uint32_t LxFlags;
+	uint32_t LxUid;
+	uint32_t LxGid;
+	uint32_t LxMode;
+	uint32_t LxDeviceIdMajor;
+	uint32_t LxDeviceIdMinor;
+} FILE_STAT_LX_INFORMATION, *PFILE_STAT_LX_INFORMATION;
+#endif
+
+/*
+ * This struct is extended from the original FILE_FULL_EA_INFORMATION of
+ * Microsoft Windows.
+ */
+struct wsl_full_ea_info_t {
+	uint32_t NextEntryOffset;
+	uint8_t Flags;
+	uint8_t EaNameLength;
+	uint16_t EaValueLength;
+	char EaName[7];
+	char EaValue[4];
+	char Padding[1];
+};
+
+enum {
+	FileStatLxInformation = 70,
+};
+__declspec(dllimport) NTSTATUS WINAPI
+	NtQueryInformationFile(HANDLE FileHandle,
+			       PIO_STATUS_BLOCK IoStatusBlock,
+			       PVOID FileInformation, ULONG Length,
+			       uint32_t FileInformationClass);
+__declspec(dllimport) NTSTATUS WINAPI
+	NtSetInformationFile(HANDLE FileHandle, PIO_STATUS_BLOCK IoStatusBlock,
+			     PVOID FileInformation, ULONG Length,
+			     uint32_t FileInformationClass);
+__declspec(dllimport) NTSTATUS WINAPI
+	NtSetEaFile(HANDLE FileHandle, PIO_STATUS_BLOCK IoStatusBlock,
+		    PVOID EaBuffer, ULONG EaBufferSize);
+
+int set_wsl_mode_bits_by_handle(HANDLE h, _mode_t mode)
+{
+	uint32_t value = mode;
+	struct wsl_full_ea_info_t ea_info;
+	IO_STATUS_BLOCK iob;
+	/* mode should be valid to make WSL happy */
+	assert(S_ISREG(mode) || S_ISDIR(mode));
+	ea_info.NextEntryOffset = 0;
+	ea_info.Flags = 0;
+	ea_info.EaNameLength = 6;
+	ea_info.EaValueLength = sizeof(value); /* 4 */
+	strlcpy(ea_info.EaName, "$LXMOD", sizeof(ea_info.EaName));
+	memcpy(ea_info.EaValue, &value, sizeof(value));
+	ea_info.Padding[0] = 0;
+	return NtSetEaFile(h, &iob, &ea_info, sizeof(ea_info));
+}
+
+int get_wsl_mode_bits_by_handle(HANDLE h, _mode_t *mode)
+{
+	FILE_STAT_LX_INFORMATION fxi;
+	IO_STATUS_BLOCK iob;
+	if (NtQueryInformationFile(h, &iob, &fxi, sizeof(fxi),
+				   FileStatLxInformation) == 0) {
+		if (fxi.LxFlags & LX_FILE_METADATA_HAS_MODE)
+			*mode = (_mode_t)fxi.LxMode;
+		return 0;
+	}
+	return -1;
+}
diff --git a/compat/win32/wsl.h b/compat/win32/wsl.h
new file mode 100644
index 00000000000000..1f5ad7e67a4fc2
--- /dev/null
+++ b/compat/win32/wsl.h
@@ -0,0 +1,12 @@
+#ifndef COMPAT_WIN32_WSL_H
+#define COMPAT_WIN32_WSL_H
+
+int are_wsl_compatible_mode_bits_enabled(void);
+
+int copy_wsl_mode_bits_from_disk(const wchar_t *wpath, ssize_t wpathlen,
+				 _mode_t *mode);
+
+int get_wsl_mode_bits_by_handle(HANDLE h, _mode_t *mode);
+int set_wsl_mode_bits_by_handle(HANDLE h, _mode_t mode);
+
+#endif
diff --git a/config.mak.uname b/config.mak.uname
index fb0497b0270d51..d500245d814efd 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -502,7 +502,7 @@ endif
 		compat/win32/path-utils.o \
 		compat/win32/pthread.o compat/win32/syslog.o \
 		compat/win32/trace2_win32_process_info.o \
-		compat/win32/dirent.o compat/win32/fscache.o
+		compat/win32/dirent.o compat/win32/fscache.o compat/win32/wsl.o
 	COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DDETECT_MSYS_TTY -DENSURE_MSYSTEM_IS_SET -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
 	BASIC_LDFLAGS = -IGNORE:4217 -IGNORE:4049 -NOLOGO
 	# invalidcontinue.obj allows Git's source code to close the same file
@@ -704,7 +704,7 @@ ifeq ($(uname_S),MINGW)
 		compat/win32/flush.o \
 		compat/win32/path-utils.o \
 		compat/win32/pthread.o compat/win32/syslog.o \
-		compat/win32/dirent.o compat/win32/fscache.o
+		compat/win32/dirent.o compat/win32/fscache.o compat/win32/wsl.o
 	BASIC_CFLAGS += -DWIN32
 	EXTLIBS += -lws2_32
 	GITLIBS += git.res
diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index 9540631852a028..90553639179e04 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -307,6 +307,7 @@ if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
 		compat/win32/syslog.c
 		compat/win32/trace2_win32_process_info.c
 		compat/win32/dirent.c
+		compat/win32/wsl.c
 		compat/nedmalloc/nedmalloc.c
 		compat/strdup.c
 		compat/win32/fscache.c)

From c9076dfb63dd04542f08d4ddcaf7612397f51089 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 23 Apr 2018 00:24:29 +0200
Subject: [PATCH 244/259] mingw: really handle SIGINT

Previously, we did not install any handler for Ctrl+C, but now we really
want to because the MSYS2 runtime learned the trick to call the
ConsoleCtrlHandler when Ctrl+C was pressed.

With this, hitting Ctrl+C while `git log` is running will only terminate
the Git process, but not the pager. This finally matches the behavior on
Linux and on macOS.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/compat/mingw.c b/compat/mingw.c
index 2a57def36b1af6..4d473043b0ffa3 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -3880,7 +3880,14 @@ static void adjust_symlink_flags(void)
 		symlink_file_flags |= 2;
 		symlink_directory_flags |= 2;
 	}
+}
 
+static BOOL WINAPI handle_ctrl_c(DWORD ctrl_type)
+{
+	if (ctrl_type != CTRL_C_EVENT)
+		return FALSE; /* we did not handle this */
+	mingw_raise(SIGINT);
+	return TRUE; /* we did handle this */
 }
 
 #ifdef _MSC_VER
@@ -3916,6 +3923,8 @@ int wmain(int argc, const wchar_t **wargv)
 #endif
 #endif
 
+	SetConsoleCtrlHandler(handle_ctrl_c, TRUE);
+
 	maybe_redirect_std_handles();
 	adjust_symlink_flags();
 	fsync_object_files = 1;

From 25eeae7aa1772841a57a4839a456bd0192a6c97b Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mon, 13 Feb 2023 13:31:35 +0100
Subject: [PATCH 245/259] Describe Git for Windows' architecture [no ci]

The Git for Windows project has grown quite complex over the years,
certainly much more complex than during the first years where the
`msysgit.git` repository was abusing Git for package management purposes
and the `git/git` fork was called `4msysgit.git`.

Let's describe the status quo in a thorough way.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 ARCHITECTURE.md | 130 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 130 insertions(+)
 create mode 100644 ARCHITECTURE.md

diff --git a/ARCHITECTURE.md b/ARCHITECTURE.md
new file mode 100644
index 00000000000000..9225b99a28be13
--- /dev/null
+++ b/ARCHITECTURE.md
@@ -0,0 +1,130 @@
+# Architecture of Git for Windows
+
+Git for Windows is a complex project.
+
+## What _is_ Git for Windows?
+
+### A fork of `git/git`
+
+First and foremost, it is a friendly fork of [`git/git`](https://github.com/git/git), aiming to improve Git's Windows support. The [`git-for-windows/git`](https://github.com/git-for-windows/git) repository contains dozens of topics on top of `git/git`, some awaiting to be "upstreamed" (i.e. to be contributed to `git/git`), some still being stabilized, and a few topics are specific to the Git for Windows project and are not intended to be integrated into `git/git` at all.
+
+### Enhancing and maintaining Git's support for Windows
+
+On the source code side, Git's Windows support is made a bit more tricky than strictly necessary by the fact that Git does not have any platform abstraction layer (unlike other version control systems, such as Subversion). It relies on the presence of POSIX features such as the `hstrerror()` function, and on platforms lacking that functionality, Git provides shims. That leads to some challenges e.g. with the `stat()` function which is very slow on Windows because it has to collect much more metadata than what e.g. the very quick `GetFileAttributesExW()` Win32 API function provides, even when Git calls `stat()` merely to test for the presence of a file (for which all that gathered metadata is totally irrelevant).
+
+### Providing more than just source code
+
+In contrast to the Git project, Git for Windows not only publishes tagged source code versions, but full builds of Git. In fact, Git for Windows' primary purpose, as far as most users are concerned, is to provide a convenient installer that end-users can run to have Git on their computer, without ever having to check out `git-for-windows/git` let alone build it. In essence, Git for Windows has to maintain a separate project altogether in addition to the fork of `git/git`, just to build these release artifacts: [`git-for-windows/build-extra`](https://github.com/git-for-windows/build-extra). This repository also contains the definition for a couple of other release artifacts published by Git for Windows, e.g. the "portable" edition of Git for Windows which is a self-extracting 7-Zip archive that does not need to be installed.
+
+### A software distribution, really
+
+Another aspect that contributes to the complexity of Git for Windows is that it is not just building `git.exe` and distributes that. Due to its heritage within the Linux project, Git takes certain things for granted, such as the presence of a Unix shell, or for that matter, a package management system from which dependencies can be fetched and updated independently of Git itself. Things that are distinctly not present in most Windows setups. To accommodate for that, Git for Windows originally relied on the MSys project, a minimal fork of Cygwin providing a Unix shell ("Bash"), a Perl interpreter and similar Unix-like tools, and on the MINGW project, a project to build libraries and executables using a GNU C Compiler that relies only on Win32 API functions. As of Git for Windows v2.x, the project has switched away from [MSys](https://sourceforge.net/projects/mingw/files/MSYS/)/[MinGW](https://osdn.net/projects/mingw/) (due to less-than-active maintenance) to [the MSYS2 project](https://msys2.org). That switch brought along the benefit of a robust package management system based on [Pacman](https://archlinux.org/pacman/) (hailing from Arch Linux). To support Windows users, who are in general unfamiliar with Linux-like package management and the need to update installed packages frequently, Git for Windows bundles a subset of its own fork of MSYS2. To put things in perspective: Git for Windows bundles files from ~170 packages, one of which contains Git, and another one contains Git's help files. In that respect, Git for Windows acts like a distribution more than like a mere single software application.
+
+Most of MSYS2's packages that are bundled in Git for Windows are consumed directly from MSYS2. Others need forks that are maintained by Git for Windows project, to support Git for Windows better. These forks live in the [`git-for-windows/MSYS2-packages`](https://github.com/git-for-windows/MSYS2-packages) and [`git-for-windows/MINGW-packages`](https://github.com/git-for-windows/MINGW-packages) repositories. There are several reasons justifying these forks. For example, the Git for Windows' flavor of the MSYS2 runtime behaves like Git's test suite expects it while MSYS2's flavor does not. Another example: The Bash executable bundled in Git for Windows is code-signed with the same certificate as `git.exe` to help anti-malware programs get out of the users' way. That is why Git for Windows maintains its own `bash` Pacman package. And since MSYS2 dropped 32-bit support already, Git for Windows has to update the 32-bit Pacman packages itself, which is done in the git-for-windows/MSYS2-packages repository. (Side note: the 32-bit issue is a bit more complicated, actually: MSYS2 _still_ builds _MINGW_ packages targeting i686 processors, but no longer any _MSYS_ packages for said processor architecture, and Git for Windows does not keep all of the 32-bit MSYS packages up to date but instead judiciously decides which packages are vital enough as far as Git is concerned to justify the maintenance cost.)
+
+### Supporting third-party applications that use Git's functionality
+
+Since the infrastructure required by Git is non-trivial the installer (or for that matter, the Portable Git) is not exactly light-weight: As of January 2023, both artifacts are over fifty megabytes. This is a problem for third-party applications wishing to bundle a version of Git for Windows, which is often advisable given that applications may depend on features that have been introduced only in recent Git versions and therefore relying on an installed Git for Windows could break things. To help with that, the Git for Windows project also provides MinGit as a release artifact, a zip file that is much smaller than the full installer and that contains only the parts of Git for Windows relevant for third-party applications. It lacks Git GUI, for example, as well as the terminal program MinTTY, or for that matter, the documentation.
+
+### Supporting `git/git`'s GitHub workflows
+
+The Git for Windows project is also responsible for keeping the Windows part of `git/git`'s automated builds up and running. On Windows, there is no canonical and easy way to get a build environment necessary to build Git and run its test suite, therefore this is a non-trivial task that comes with its own maintenance cost. Git for Windows provides two GitHub Actions to help with that: [`git-for-windows/setup-git-for-windows-sdk`](https://github.com/git-for-windows/setup-git-for-windows-sdk) to set up a tiny subset of Git for Windows' full SDK (which would require about 500MB to be cloned, as opposed to the ~75MB of that subset) and [`git-for-windows/get-azure-pipelines-artifact`](https://github.com/git-for-windows/get-azure-pipelines-artifact) e.g. to download some regularly pre-built artifacts (for example, when `git/git`'s automated tests ran on an Ubuntu version that did not provide an up to date [Coccinelle](https://coccinelle.gitlabpages.inria.fr/website/) package, this GitHub Action was used to download a pre-built version of that Debian package).
+
+## Maintaining Git for Windows' components
+
+Git for Windows uses a combination of [a GitHub App called GitForWindowsHelper](https://github.com/git-for-windows/gfw-helper-github-app) (to listen for so-called [slash commands](https://github.com/git-for-windows/gfw-helper-github-app#slash-commands)) combined with workflows in [the `git-for-windows-automation` repository](https://github.com/git-for-windows/git-for-windows-automation/) (for computationally heavy tasks) to support Git for Windows' repetitive tasks.
+
+This heavy automation serves two purposes:
+
+1. Document the knowledge about "how things are done" in the Git for Windows project.
+2. Make Git for Windows' maintenance less tedious by off-loading as many tasks onto machines as possible.
+
+One neat trick of some `git-for-windows-automation` workflows is that they "mirror back" check runs to the targeted PRs in another repository. This essentially allows versioning the source code independently of the workflow definition.
+
+Here is a diagram showing how the bits and pieces fit together.
+
+```mermaid
+graph LR
+  A[`monitor-components`] --> |opens| B
+  B{issues labeled<br />`component-update`} --> |/open pr| C
+  C((GitForWindowsHelper)) --> |triggers| D
+  D[`open-pr`] --> |opens| E
+  E{PR in</br>MINGW-packages<br />MSYS2-packages<br />build-extra} --> |closes| B
+  E --> |/deploy| F
+  F((GitForWindowsHelper)) --> |triggers| G
+  G[`build-and-deploy`] --> |deploys to| H
+  H{Pacman repository}
+  C --> |backed by| I
+  F --> |backed by| I
+  I[[Azure Function]]
+  D --> |running in| J
+  G --> | running in| J
+  J[[git-for-windows-automation]]
+  K[[git-sdk-32<br />git-sdk-64<br />git-sdk-arm64]] --> |syncing from| H
+  B --> |/add release note| L
+  L[`add-release-note`]
+```
+
+For the curious mind, here are [detailed instructions how the Azure Function backing the GitForWindowsHelper GitHub App was set up](https://github.com/git-for-windows/gfw-helper-github-app#how-this-github-app-was-set-up).
+
+### The `monitor-components` workflow
+
+When new versions of components that Git for Windows builds become available, new Pacman packages have to be built. To this end, [the `monitor-components` workflow](https://github.com/git-for-windows/git/blob/main/.github/workflows/monitor-components.yml) monitors a couple of RSS feeds and opens new tickets labeled `component-update` for such new versions.
+
+### Opening Pull Requests to update Git for Windows' components
+
+After determining that such a ticket indeed indicates the need for a new Pacman package build, a Git for Windows maintainer issues the `/open pr` command via an issue comment ([example](https://github.com/git-for-windows/git/issues/4281#issuecomment-1426859787)), which gets picked up by the GitForWindowsHelper GitHub App, which in turn triggers [the `open-pr` workflow](https://github.com/git-for-windows/git-for-windows-automation/blob/main/.github/workflows/open-pr.yml) in the `git-for-windows-automation` repository.
+
+### Deploying the Pacman packages
+
+This will open a Pull Request in one of Git for Windows' repositories, and once the PR build passes, a Git for Windows maintainer issues the `/deploy` command ([example](https://github.com/git-for-windows/MINGW-packages/pull/69#issuecomment-1427591890)), which gets picked up by the GitForWindowsHelper GitHub App, which triggers [the `build-and-deploy` workflow](https://github.com/git-for-windows/git-for-windows-automation/blob/main/.github/workflows/build-and-deploy.yml).
+
+### Adding release notes
+
+Finally, once the packages have been built and deployed to the Pacman repository (which is hosted in Azure Blob Storage), a Git for Windows maintainer will merge the PR(s), which in turn will close the ticket, and the maintainer then issues an `/add release note` command ([example](https://github.com/git-for-windows/MINGW-packages/pull/69#issuecomment-1427782230)), which again gets picked up by the GitForWindowsHelper GitHub App that triggers [the `add-release-note` workflow](https://github.com/git-for-windows/build-extra/blob/main/.github/workflows/add-release-note.yml) that creates and pushes a new commit to the `ReleaseNotes.md` file in `build-extra` ([example](https://github.com/git-for-windows/build-extra/commit/b39c148ff8dc0e987afdb677d17c46a8e99fd0ef)).
+
+## Releasing official Git for Windows versions
+
+A relatively infrequent part of Git for Windows' maintainers' duties, if the most rewarding part, is the task of releasing new versions of Git for Windows.
+
+Most commonly, this is done in response to the "upstream" Git project releasing a new version. When that happens, a Git for Windows maintainer runs [the helper script](https://github.com/git-for-windows/build-extra/blob/main/shears.sh) to perform a "merging rebase" (i.e. a rebase that starts with a fake-merge of the previous tip commit, to maintain both a clean set of commits as well as a [fast-forwarding](https://git-scm.com/docs/git-merge#Documentation/git-merge.txt---ff-only) commit history).
+
+Once that is done, the maintainer will open a Pull Request to benefit from the automated builds and tests ([example](https://github.com/git-for-windows/git/pull/4160)) as well as from reviews of the [`range-diff`](https://git-scm.com/docs/git-range-diff) relative to the current `main` branch.
+
+Once everything looks good, the maintainer will issue the `/git-artifacts` command ([example](https://github.com/git-for-windows/git/pull/4160#issuecomment-1346801735)). This will trigger an automated workflow that builds all of the release artifacts: installers, Portable Git, MinGit, `.tar.xz` archive and a NuGet package. Apart from the NuGet package, two sets of artifacts are built: targeting 32-bit ("x86") and 64-bit ("amd64").
+
+Once these artifacts are built, the maintainer will download the installer and run [the "pre-flight checklist"](https://github.com/git-for-windows/build-extra/blob/main/installer/checklist.txt).
+
+If everything looks good, a `/release` command will be issued, which triggers yet another workflow that will download the just-built-and-verified release artifacts, publish them as a new GitHub release, publish the NuGet packages, deploy the Pacman packages to the Pacman repository, send out an announcement mail, and update the respective repositories including [Git for Windows' website](https://gitforwindows.org/).
+
+As mentioned [before](#architecture-of-git-for-windows), the `/git-artifacts` and `/release` commands are picked up by the GitForWindowsHelper GitHub App which subsequently triggers the respective workflows in the `git-for-windows-automation` repository. Here is a diagram:
+
+```mermaid
+graph LR
+  A{Pull Request<br />updating to<br />new Git version} --> |/git-artifacts| B
+  B((GitForWindowsHelper)) --> |triggers| C
+  C[`tag-git`] --> |upon successful build<br />triggers| D
+  D((GitForWindowsHelper)) --> |triggers| E
+  E[`git-artifacts`]
+  E --> |maintainer verifies artifacts| E
+  A --> |upon verified `git-artifacts`<br />/release| F
+  F[`release-git`]
+  C --> |running in| J
+  E --> | running in| J
+  F --> | running in| J
+  J[[git-for-windows-automation]]
+```
+
+## Managing Windows/ARM64 builds
+
+The GitForWindowsHelper comes in real handy for Git for Windows' Pacman packages for the `aarch64` architecture, i.e. for Windows/ARM64. These packages cannot be built in regular hosted GitHub Actions runners because there are none of that architecture. To help with that, the respective workflows in `git-for-windows-automation` use the label `runs-on: ["Windows", "ARM64"]` to indicate that they need a self-hosted Windows/ARM64 runner.
+
+It would not be cost-effective to have a VM running permanently, hosting such a self-hosted runner: Git for Windows does not build such packages often enough (usually once or twice per week is more the norm).
+
+Therefore, VMs providing self-hosted GitHub Actions runners are spun up and torn down as needed. This job is done by the GitForWindowsHelper:
+
+- When a job is queued asking for above-mentioned labels, [the `create-self-hosted-runner` workflow](https://github.com/git-for-windows/git-for-windows-automation/blob/09ec165f44a0a3d84d8f0e26a4939667b4522635/.github/workflows/create-azure-self-hosted-runners.yml) is started. This deploys an Azure Resource Management template that creates an ephemeral self-hosted runner (i.e. a runner that will pick up one job and then is immediately unregistered).
+
+- When a job with above-mentioned labels has finished, the GitForWindowsHelper triggers [the `delete-self-hosted-runner` workflow](https://github.com/git-for-windows/git-for-windows-automation/blob/09ec165f44a0a3d84d8f0e26a4939667b4522635/.github/workflows/delete-self-hosted-runner.yml) that tears down the now no longer used VM.
+
+The GitForWindowsHelper GitHub App will also detect when a job is queued for a PR from a forked repository. This is considered unauthorized use, and the job will be canceled immediately by the GitHub App instead of spinning up a self-hosted runner for it.
\ No newline at end of file

From a4538e1abb104b4a75e7abec24d702848bc17df3 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 11 Oct 2019 13:22:24 +0200
Subject: [PATCH 246/259] Modify the Code of Conduct for Git for Windows

The Git project followed Git for Windows' lead and added their Code of
Conduct, based on the Contributor Covenant v1.4, later updated to v2.0.

We adapt it slightly to Git for Windows.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 CODE_OF_CONDUCT.md | 58 +++++++++++++++++++++-------------------------
 1 file changed, 26 insertions(+), 32 deletions(-)

diff --git a/CODE_OF_CONDUCT.md b/CODE_OF_CONDUCT.md
index e58917c50a96dc..4daef7e3ce9196 100644
--- a/CODE_OF_CONDUCT.md
+++ b/CODE_OF_CONDUCT.md
@@ -1,9 +1,9 @@
-# Git Code of Conduct
+# Git for Windows Code of Conduct
 
 This code of conduct outlines our expectations for participants within
-the Git community, as well as steps for reporting unacceptable behavior.
-We are committed to providing a welcoming and inspiring community for
-all and expect our code of conduct to be honored. Anyone who violates
+the **Git for Windows** community, as well as steps for reporting unacceptable
+behavior. We are committed to providing a welcoming and inspiring community
+for all and expect our code of conduct to be honored. Anyone who violates
 this code of conduct may be banned from the community.
 
 ## Our Pledge
@@ -12,8 +12,8 @@ We as members, contributors, and leaders pledge to make participation in our
 community a harassment-free experience for everyone, regardless of age, body
 size, visible or invisible disability, ethnicity, sex characteristics, gender
 identity and expression, level of experience, education, socio-economic status,
-nationality, personal appearance, race, religion, or sexual identity
-and orientation.
+nationality, personal appearance, race, caste, color, religion, or sexual
+identity and orientation.
 
 We pledge to act and interact in ways that contribute to an open, welcoming,
 diverse, inclusive, and healthy community.
@@ -28,17 +28,17 @@ community include:
 * Giving and gracefully accepting constructive feedback
 * Accepting responsibility and apologizing to those affected by our mistakes,
   and learning from the experience
-* Focusing on what is best not just for us as individuals, but for the
-  overall community
+* Focusing on what is best not just for us as individuals, but for the overall
+  community
 
 Examples of unacceptable behavior include:
 
-* The use of sexualized language or imagery, and sexual attention or
-  advances of any kind
+* The use of sexualized language or imagery, and sexual attention or advances of
+  any kind
 * Trolling, insulting or derogatory comments, and personal or political attacks
 * Public or private harassment
-* Publishing others' private information, such as a physical or email
-  address, without their explicit permission
+* Publishing others' private information, such as a physical or email address,
+  without their explicit permission
 * Other conduct which could reasonably be considered inappropriate in a
   professional setting
 
@@ -58,20 +58,14 @@ decisions when appropriate.
 
 This Code of Conduct applies within all community spaces, and also applies when
 an individual is officially representing the community in public spaces.
-Examples of representing our community include using an official e-mail address,
+Examples of representing our community include using an official email address,
 posting via an official social media account, or acting as an appointed
 representative at an online or offline event.
 
 ## Enforcement
 
 Instances of abusive, harassing, or otherwise unacceptable behavior may be
-reported to the community leaders responsible for enforcement at
-git@sfconservancy.org, or individually:
-
-  - Ævar Arnfjörð Bjarmason <avarab@gmail.com>
-  - Christian Couder <christian.couder@gmail.com>
-  - Junio C Hamano <gitster@pobox.com>
-  - Taylor Blau <me@ttaylorr.com>
+reported by contacting the Git for Windows maintainer.
 
 All complaints will be reviewed and investigated promptly and fairly.
 
@@ -94,15 +88,15 @@ behavior was inappropriate. A public apology may be requested.
 
 ### 2. Warning
 
-**Community Impact**: A violation through a single incident or series
-of actions.
+**Community Impact**: A violation through a single incident or series of
+actions.
 
 **Consequence**: A warning with consequences for continued behavior. No
 interaction with the people involved, including unsolicited interaction with
 those enforcing the Code of Conduct, for a specified period of time. This
 includes avoiding interactions in community spaces as well as external channels
-like social media. Violating these terms may lead to a temporary or
-permanent ban.
+like social media. Violating these terms may lead to a temporary or permanent
+ban.
 
 ### 3. Temporary Ban
 
@@ -118,27 +112,27 @@ Violating these terms may lead to a permanent ban.
 ### 4. Permanent Ban
 
 **Community Impact**: Demonstrating a pattern of violation of community
-standards, including sustained inappropriate behavior,  harassment of an
+standards, including sustained inappropriate behavior, harassment of an
 individual, or aggression toward or disparagement of classes of individuals.
 
-**Consequence**: A permanent ban from any sort of public interaction within
-the community.
+**Consequence**: A permanent ban from any sort of public interaction within the
+community.
 
 ## Attribution
 
 This Code of Conduct is adapted from the [Contributor Covenant][homepage],
-version 2.0, available at
-[https://www.contributor-covenant.org/version/2/0/code_of_conduct.html][v2.0].
+version 2.1, available at
+[https://www.contributor-covenant.org/version/2/1/code_of_conduct.html][v2.1].
 
 Community Impact Guidelines were inspired by
 [Mozilla's code of conduct enforcement ladder][Mozilla CoC].
 
 For answers to common questions about this code of conduct, see the FAQ at
-[https://www.contributor-covenant.org/faq][FAQ]. Translations are available
-at [https://www.contributor-covenant.org/translations][translations].
+[https://www.contributor-covenant.org/faq][FAQ]. Translations are available at
+[https://www.contributor-covenant.org/translations][translations].
 
 [homepage]: https://www.contributor-covenant.org
-[v2.0]: https://www.contributor-covenant.org/version/2/0/code_of_conduct.html
+[v2.1]: https://www.contributor-covenant.org/version/2/1/code_of_conduct.html
 [Mozilla CoC]: https://github.com/mozilla/diversity
 [FAQ]: https://www.contributor-covenant.org/faq
 [translations]: https://www.contributor-covenant.org/translations

From 4d02bc6dd47155175eda9c63c4827528b418aa10 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 29 Sep 2020 13:50:59 +0200
Subject: [PATCH 247/259] Add a GitHub workflow to monitor component updates
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Rather than using private IFTTT Applets that send mails to this
maintainer whenever a new version of a Git for Windows component was
released, let's use the power of GitHub workflows to make this process
publicly visible.

This workflow monitors the Atom/RSS feeds, and opens a ticket whenever a
new version was released.

Note: Bash sometimes releases multiple patched versions within a few
minutes of each other (i.e. 5.1p1 through 5.1p4, 5.0p15 and 5.0p16). The
MSYS2 runtime also has a similar system. We can address those patches as
a group, so we shouldn't get multiple issues about them.

Note further: We're not acting on newlib releases, OpenSSL alphas, Perl
release candidates or non-stable Perl releases. There's no need to open
issues about them.

Co-authored-by: Matthias Aßhauer <mha1993@live.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 .github/workflows/monitor-components.yml | 98 ++++++++++++++++++++++++
 1 file changed, 98 insertions(+)
 create mode 100644 .github/workflows/monitor-components.yml

diff --git a/.github/workflows/monitor-components.yml b/.github/workflows/monitor-components.yml
new file mode 100644
index 00000000000000..fedc6add69a9e0
--- /dev/null
+++ b/.github/workflows/monitor-components.yml
@@ -0,0 +1,98 @@
+name: Monitor component updates
+
+# Git for Windows is a slightly modified subset of MSYS2. Some of its
+# components are maintained by Git for Windows, others by MSYS2. To help
+# keeping the former up to date, this workflow monitors the Atom/RSS feeds
+# and opens new tickets for each new component version.
+
+on:
+  schedule:
+    - cron: "23 8,11,14,17 * * *"
+  workflow_dispatch:
+
+env:
+  CHARACTER_LIMIT: 5000
+  MAX_AGE: 7d
+
+jobs:
+  job:
+    # Only run this in Git for Windows' fork
+    if: github.event.repository.owner.login == 'git-for-windows'
+    runs-on: ubuntu-latest
+    permissions:
+      issues: write
+    strategy:
+      matrix:
+        component:
+          - label: git
+            feed: https://github.com/git/git/tags.atom
+          - label: git-lfs
+            feed: https://github.com/git-lfs/git-lfs/tags.atom
+          - label: git-credential-manager
+            feed: https://github.com/git-ecosystem/git-credential-manager/tags.atom
+          - label: tig
+            feed: https://github.com/jonas/tig/tags.atom
+          - label: cygwin
+            feed: https://github.com/cygwin/cygwin/releases.atom
+            title-pattern: ^(?!.*newlib)
+          - label: msys2-runtime-package
+            feed: https://github.com/msys2/MSYS2-packages/commits/master/msys2-runtime.atom
+          - label: msys2-runtime
+            feed: https://github.com/msys2/msys2-runtime/commits/HEAD.atom
+            aggregate: true
+          - label: openssh
+            feed: https://github.com/openssh/openssh-portable/tags.atom
+          - label: libfido2
+            feed: https://github.com/Yubico/libfido2/tags.atom
+          - label: libcbor
+            feed: https://github.com/PJK/libcbor/tags.atom
+          - label: openssl
+            feed: https://github.com/openssl/openssl/tags.atom
+            title-pattern: ^(?!.*alpha)
+          - label: gnutls
+            feed: https://gnutls.org/news.atom
+          - label: heimdal
+            feed: https://github.com/heimdal/heimdal/tags.atom
+          - label: git-sizer
+            feed: https://github.com/github/git-sizer/tags.atom
+          - label: gitflow
+            feed: https://github.com/petervanderdoes/gitflow-avh/tags.atom
+          - label: curl
+            feed: https://github.com/curl/curl/tags.atom
+          - label: libgpg-error
+            feed: https://github.com/gpg/libgpg-error/releases.atom
+            title-pattern: ^libgpg-error-[0-9\.]*$
+          - label: libgcrypt
+            feed: https://github.com/gpg/libgcrypt/releases.atom
+            title-pattern: ^libgcrypt-[0-9\.]*$
+          - label: gpg
+            feed: https://github.com/gpg/gnupg/releases.atom
+          - label: mintty
+            feed: https://github.com/mintty/mintty/releases.atom
+          - label: 7-zip
+            feed: https://sourceforge.net/projects/sevenzip/rss?path=/7-Zip
+            aggregate: true
+          - label: bash
+            feed: https://git.savannah.gnu.org/cgit/bash.git/atom/?h=master
+            aggregate: true
+          - label: perl
+            feed: https://github.com/Perl/perl5/tags.atom
+            title-pattern: ^(?!.*(5\.[0-9]+[13579]|RC))
+          - label: pcre2
+            feed: https://github.com/PCRE2Project/pcre2/tags.atom
+          - label: mingw-w64-llvm
+            feed: https://github.com/msys2/MINGW-packages/commits/master/mingw-w64-llvm.atom
+          - label: innosetup
+            feed: https://github.com/jrsoftware/issrc/tags.atom
+      fail-fast: false
+    steps:
+      - uses: git-for-windows/rss-to-issues@v0
+        with:
+          feed: ${{matrix.component.feed}}
+          prefix: "[New ${{matrix.component.label}} version]"
+          labels: component-update
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          character-limit: ${{ env.CHARACTER_LIMIT }}
+          max-age: ${{ env.MAX_AGE }}
+          aggregate: ${{matrix.component.aggregate}}
+          title-pattern: ${{matrix.component.title-pattern}}

From dd7859a9ba2be14dbc170c4e1fe08962dc381dcc Mon Sep 17 00:00:00 2001
From: Derrick Stolee <dstolee@microsoft.com>
Date: Thu, 1 Mar 2018 12:10:14 -0500
Subject: [PATCH 248/259] CONTRIBUTING.md: add guide for first-time
 contributors

Getting started contributing to Git can be difficult on a Windows
machine. CONTRIBUTING.md contains a guide to getting started, including
detailed steps for setting up build tools, running tests, and
submitting patches to upstream.

[includes an example by Pratik Karki how to submit v2, v3, v4, etc.]

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
---
 CONTRIBUTING.md | 417 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 417 insertions(+)
 create mode 100644 CONTRIBUTING.md

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 00000000000000..ca9770df8c4808
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,417 @@
+How to Contribute to Git for Windows
+====================================
+
+Git was originally designed for Unix systems and still today, all the build tools for the Git
+codebase assume you have standard Unix tools available in your path. If you have an open-source
+mindset and want to start contributing to Git, but primarily use a Windows machine, then you may
+have trouble getting started. This guide is for you.
+
+Get the Source
+--------------
+
+Clone the [GitForWindows repository on GitHub](https://github.com/git-for-windows/git).
+It is helpful to create your own fork for storing your development branches.
+
+Windows uses different line endings than Unix systems. See
+[this GitHub article on working with line endings](https://help.github.com/articles/dealing-with-line-endings/#refreshing-a-repository-after-changing-line-endings)
+if you have trouble with line endings.
+
+Build the Source
+----------------
+
+First, download and install the latest [Git for Windows SDK (64-bit)](https://github.com/git-for-windows/build-extra/releases/latest).
+When complete, you can run the Git SDK, which creates a new Git Bash terminal window with
+the additional development commands, such as `make`.
+
+    As of time of writing, the SDK uses a different credential manager, so you may still want to use normal Git
+    Bash for interacting with your remotes.  Alternatively, use SSH rather than HTTPS and
+    avoid credential manager problems.
+
+You should now be ready to type `make` from the root of your `git` source directory.
+Here are some helpful variations:
+
+* `make -j[N] DEVELOPER=1`: Compile new sources using up to N concurrent processes.
+  The `DEVELOPER` flag turns on all warnings; code failing these warnings will not be
+  accepted upstream ("upstream" = "the core Git project").
+* `make clean`: Delete all compiled files.
+
+When running `make`, you can use `-j$(nproc)` to automatically use the number of processors
+on your machine as the number of concurrent build processes.
+
+You can go deeper on the Windows-specific build process by reading the
+[technical overview](https://github.com/git-for-windows/git/wiki/Technical-overview) or the
+[guide to compiling Git with Visual Studio](https://github.com/git-for-windows/git/wiki/Compiling-Git-with-Visual-Studio).
+
+## Building `git` on Windows with Visual Studio
+
+The typical approach to building `git` is to use the standard `Makefile` with GCC, as
+above. Developers working in a Windows environment may want to instead build with the
+[Microsoft Visual C++ compiler and libraries toolset (MSVC)](https://blogs.msdn.microsoft.com/vcblog/2017/03/07/msvc-the-best-choice-for-windows/).
+There are a few benefits to using MSVC over GCC during your development, including creating
+symbols for debugging and [performance tracing](https://github.com/Microsoft/perfview#perfview-overview).
+
+There are two ways to build Git for Windows using MSVC. Each have their own merits.
+
+### Using SDK Command Line
+
+Use one of the following commands from the SDK Bash window to build Git for Windows:
+
+```
+    make MSVC=1 -j12
+    make MSVC=1 DEBUG=1 -j12
+```
+
+The first form produces release-mode binaries; the second produces debug-mode binaries.
+Both forms produce PDB files and can be debugged.  However, the first is best for perf
+tracing and the second is best for single-stepping.
+
+You can then open Visual Studio and select File -> Open -> Project/Solution and select
+the compiled `git.exe` file. This creates a basic solution and you can use the debugging
+and performance tracing tools in Visual Studio to monitor a Git process. Use the Debug
+Properties page to set the working directory and command line arguments.
+
+Be sure to clean up before switching back to GCC (or to switch between debug and
+release MSVC builds):
+
+```
+    make MSVC=1 -j12 clean
+    make MSVC=1 DEBUG=1 -j12 clean
+```
+
+### Using the IDE
+
+If you prefer working in Visual Studio with a solution full of projects, then you can use
+CMake, either by letting Visual Studio configure it automatically (simply open Git's
+top-level directory via `File>Open>Folder...`) or by (downloading and) running
+[CMake](https://cmake.org) manually.
+
+What to Change?
+---------------
+
+Many new contributors ask: What should I start working on?
+
+One way to win big with the open-source community is to look at the
+[issues page](https://github.com/git-for-windows/git/issues) and see if there are any issues that
+you can fix quickly, or if anything catches your eye.
+
+You can also look at [the unofficial Chromium issues page](https://crbug.com/git) for
+multi-platform issues. You can look at recent user questions on
+[the Git mailing list](https://public-inbox.org/git).
+
+Or you can "scratch your own itch", i.e. address an issue you have with Git. The team at Microsoft where the Git for Windows maintainer works, for example, is focused almost entirely on [improving performance](https://blogs.msdn.microsoft.com/devops/2018/01/11/microsofts-performance-contributions-to-git-in-2017/).
+We approach our work by finding something that is slow and try to speed it up. We start our
+investigation by reliably reproducing the slow behavior, then running that example using
+the MSVC build and tracing the results in PerfView.
+
+You could also think of something you wish Git could do, and make it do that thing! The
+only concern I would have with this approach is whether or not that feature is something
+the community also wants. If this excites you though, go for it! Don't be afraid to
+[get involved in the mailing list](http://vger.kernel.org/vger-lists.html#git) early for
+feedback on the idea.
+
+Test Your Changes
+-----------------
+
+After you make your changes, it is important that you test your changes. Manual testing is
+important, but checking and extending the existing test suite is even more important. You
+want to run the functional tests to see if you broke something else during your change, and
+you want to extend the functional tests to be sure no one breaks your feature in the future.
+
+### Functional Tests
+
+Navigate to the `t/` directory and type `make` to run all tests or use `prove` as
+[described in the Git for Windows wiki](https://github.com/git-for-windows/git/wiki/Building-Git):
+
+```
+prove -j12 --state=failed,save ./t[0-9]*.sh
+```
+
+You can also run each test directly by running the corresponding shell script with a name
+like `tNNNN-descriptor.sh`.
+
+If you are adding new functionality, you may need to create unit tests by creating
+helper commands that test a very limited action. These commands are stored in `t/helpers`.
+When adding a helper, be sure to add a line to `t/Makefile` and to the `.gitignore` for the
+binary file you add. The Git community prefers functional tests using the full `git`
+executable, so try to exercise your new code using `git` commands before creating a test
+helper.
+
+To find out why a test failed, repeat the test with the `-x -v -d -i` options and then
+navigate to the appropriate "trash" directory to see the data shape that was used for the
+test failed step.
+
+Read [`t/README`](t/README) for more details.
+
+### Performance Tests
+
+If you are working on improving performance, you will need to be acquainted with the
+performance tests in `t/perf`. There are not too many performance tests yet, but adding one
+as your first commit in a patch series helps to communicate the boost your change provides.
+
+To check the change in performance across multiple versions of `git`, you can use the
+`t/perf/run` script. For example, to compare the performance of `git rev-list` across the
+`core/master` and `core/next` branches compared to a `topic` branch, you can run
+
+```
+cd t/perf
+./run core/master core/next topic -- p0001-rev-list.sh
+```
+
+You can also set certain environment variables to help test the performance on different
+repositories or with more repetitions. The full list is available in
+[the `t/perf/README` file](t/perf/README),
+but here are a few important ones:
+
+```
+GIT_PERF_REPO=/path/to/repo
+GIT_PERF_LARGE_REPO=/path/to/large/repo
+GIT_PERF_REPEAT_COUNT=10
+```
+
+When running the performance tests on Linux, you may see a message "Can't locate JSON.pm in
+@INC" and that means you need to run `sudo cpanm install JSON` to get the JSON perl package.
+
+For running performance tests, it can be helpful to set up a few repositories with strange
+data shapes, such as:
+
+**Many objects:** Clone repos such as [Kotlin](https://github.com/jetbrains/kotlin), [Linux](https://github.com/torvalds/linux), or [Android](https://source.android.com/setup/downloading).
+
+**Many pack-files:** You can split a fresh clone into multiple pack-files of size at most
+16MB by running `git repack -adfF --max-pack-size=16m`. See the
+[`git repack` documentation](https://git-scm.com/docs/git-repack) for more information.
+You can count the number of pack-files using `ls .git/objects/pack/*.pack | wc -l`.
+
+**Many loose objects:** If you already split your repository into multiple pack-files, then
+you can pick one to split into loose objects using `cat .git/objects/pack/[id].pack | git unpack-objects`;
+delete the `[id].pack` and `[id].idx` files after this. You can count the number of loose
+bjects using `ls .git/objects/??/* | wc -l`.
+
+**Deep history:** Usually large repositories also have deep histories, but you can use the
+[test-many-commits-1m repo](https://github.com/cirosantilli/test-many-commits-1m/) to
+target deep histories without the overhead of many objects. One issue with this repository:
+there are no merge commits, so you will need to use a different repository to test a "wide"
+commit history.
+
+**Large Index:** You can generate a large index and repo by using the scripts in
+`t/perf/repos`.  There are two scripts. `many-files.sh` which will generate a repo with
+same tree and blobs but different paths.  Using `many-files.sh -d 5 -w 10 -f 9` will create
+a repo with ~1 million entries in the index. `inflate-repo.sh` will use an existing repo
+and copy the current work tree until it is a specified size.
+
+Test Your Changes on Linux
+--------------------------
+
+It can be important to work directly on the [core Git codebase](https://github.com/git/git),
+such as a recent commit into the `master` or `next` branch that has not been incorporated
+into Git for Windows. Also, it can help to run functional and performance tests on your
+code in Linux before submitting patches to the mailing list, which focuses on many platforms.
+The differences between Windows and Linux are usually enough to catch most cross-platform
+issues.
+
+### Using the Windows Subsystem for Linux
+
+The [Windows Subsystem for Linux (WSL)](https://docs.microsoft.com/en-us/windows/wsl/install-win10)
+allows you to [install Ubuntu Linux as an app](https://www.microsoft.com/en-us/store/p/ubuntu/9nblggh4msv6)
+that can run Linux executables on top of the Windows kernel. Internally,
+Linux syscalls are interpreted by the WSL, everything else is plain Ubuntu.
+
+First, open WSL (either type "Bash" in Cortana, or execute "bash.exe" in a CMD window).
+Then install the prerequisites, and `git` for the initial clone:
+
+```
+sudo apt-get update
+sudo apt-get install git gcc make libssl-dev libcurl4-openssl-dev \
+		     libexpat-dev tcl tk gettext git-email zlib1g-dev
+```
+
+Then, clone and build:
+
+```
+git clone https://github.com/git-for-windows/git
+cd git
+git remote add -f upstream https://github.com/git/git
+make
+```
+
+Be sure to clone into `/home/[user]/` and not into any folder under `/mnt/?/` or your build
+will fail due to colons in file names.
+
+### Using a Linux Virtual Machine with Hyper-V
+
+If you prefer, you can use a virtual machine (VM) to run Linux and test your changes in the
+full environment. The test suite runs a lot faster on Linux than on Windows or with the WSL.
+You can connect to the VM using an SSH terminal like
+[PuTTY](https://www.chiark.greenend.org.uk/~sgtatham/putty/).
+
+The following instructions are for using Hyper-V, which is available in some versions of Windows.
+There are many virtual machine alternatives available, if you do not have such a version installed.
+
+* [Download an Ubuntu Server ISO](https://www.ubuntu.com/download/server).
+* Open [Hyper-V Manager](https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/quick-start/enable-hyper-v).
+* [Set up a virtual switch](https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/quick-start/connect-to-network)
+  so your VM can reach the network.
+* Select "Quick Create", name your machine, select the ISO as installation source, and un-check
+  "This virtual machine will run Windows."
+* Go through the Ubuntu install process, being sure to select to install OpenSSH Server.
+* When install is complete, log in and check the SSH server status with `sudo service ssh status`.
+    * If the service is not found, install with `sudo apt-get install openssh-server`.
+    * If the service is not running, then use `sudo service ssh start`.
+* Use `shutdown -h now` to shutdown the VM, go to the Hyper-V settings for the VM, expand Network Adapter
+  to select "Advanced Features", and set the MAC address to be static (this can save your VM from losing
+  network if shut down incorrectly).
+* Provide as many cores to your VM as you can (for parallel builds).
+* Restart your VM, but do not connect.
+* Use `ssh` in Git Bash, download [PuTTY](http://www.putty.org/), or use your favorite SSH client to connect to the VM through SSH.
+
+In order to build and use `git`, you will need the following libraries via `apt-get`:
+
+```
+sudo apt-get update
+sudo apt-get install git gcc make libssl-dev libcurl4-openssl-dev \
+                     libexpat-dev tcl tk gettext git-email zlib1g-dev
+```
+
+To get your code from your Windows machine to the Linux VM, it is easiest to push the branch to your fork of Git and clone your fork in the Linux VM.
+
+Don't forget to set your `git` config with your preferred name, email, and editor.
+
+Polish Your Commits
+-------------------
+
+Before submitting your patch, be sure to read the [coding guidelines](https://github.com/git/git/blob/master/Documentation/CodingGuidelines)
+and check your code to match as best you can. This can be a lot of effort, but it saves
+time during review to avoid style issues.
+
+The other possibly major difference between the mailing list submissions and GitHub PR workflows
+is that each commit will be reviewed independently. Even if you are submitting a
+patch series with multiple commits, each commit must stand on it's own and be reviewable
+by itself. Make sure the commit message clearly explain the why of the commit not the how.
+Describe what is wrong with the current code and how your changes have made the code better.
+
+When preparing your patch, it is important to put yourself in the shoes of the Git community.
+Accepting a patch requires more justification than approving a pull request from someone on
+your team. The community has a stable product and is responsible for keeping it stable. If
+you introduce a bug, then they cannot count on you being around to fix it. When you decided
+to start work on a new feature, they were not part of the design discussion and may not
+even believe the feature is worth introducing.
+
+Questions to answer in your patch message (and commit messages) may include:
+* Why is this patch necessary?
+* How does the current behavior cause pain for users?
+* What kinds of repositories are necessary for noticing a difference?
+* What design options did you consider before writing this version? Do you have links to
+  code for those alternate designs?
+* Is this a performance fix? Provide clear performance numbers for various well-known repos.
+
+Here are some other tips that we use when cleaning up our commits:
+
+* Commit messages should be wrapped at 76 columns per line (or less; 72 is also a
+  common choice).
+* Make sure the commits are signed off using `git commit (-s|--signoff)`. See
+  [SubmittingPatches](https://github.com/git/git/blob/v2.8.1/Documentation/SubmittingPatches#L234-L286)
+  for more details about what this sign-off means.
+* Check for whitespace errors using `git diff --check [base]...HEAD` or `git log --check`.
+* Run `git rebase --whitespace=fix` to correct upstream issues with whitespace.
+* Become familiar with interactive rebase (`git rebase -i`) because you will be reordering,
+  squashing, and editing commits as your patch or series of patches is reviewed.
+* Make sure any shell scripts that you add have the executable bit set on them.  This is
+  usually for test files that you add in the `/t` directory.  You can use
+  `git add --chmod=+x [file]` to update it. You can test whether a file is marked as executable
+  using `git ls-files --stage \*.sh`; the first number is 100755 for executable files.
+* Your commit titles should match the "area: change description" format. Rules of thumb:
+    * Choose "<area>: " prefix appropriately.
+    * Keep the description short and to the point.
+    * The word that follows the "<area>: " prefix is not capitalized.
+    * Do not include a full-stop at the end of the title.
+    * Read a few commit messages -- using `git log origin/master`, for instance -- to
+      become acquainted with the preferred commit message style.
+* Build source using  `make DEVELOPER=1` for extra-strict compiler warnings.
+
+Submit Your Patch
+-----------------
+
+Git for Windows [accepts pull requests on GitHub](https://github.com/git-for-windows/git/pulls), but
+these are reserved for Windows-specific improvements. For core Git, submissions are accepted on
+[the Git mailing list](https://public-inbox.org/git).
+
+### Configure Git to Send Emails
+
+There are a bunch of options for configuring the `git send-email` command. These options can
+be found in the documentation for
+[`git config`](https://git-scm.com/docs/git-config) and
+[`git send-email`](https://git-scm.com/docs/git-send-email).
+
+```
+git config --global sendemail.smtpserver <smtp server>
+git config --global sendemail.smtpserverport 587
+git config --global sendemail.smtpencryption tls
+git config --global sendemail.smtpuser <email address>
+```
+
+To avoid storing your password in the config file, store it in the Git credential manager:
+
+```
+$ git credential fill
+protocol=smtp
+host=<stmp server>
+username=<email address>
+password=password
+```
+
+Before submitting a patch, read the [Git documentation on submitting patches](https://github.com/git/git/blob/master/Documentation/SubmittingPatches).
+
+To construct a patch set, use the `git format-patch` command. There are three important options:
+
+* `--cover-letter`: If specified, create a `[v#-]0000-cover-letter.patch` file that can be
+  edited to describe the patch as a whole. If you previously added a branch description using
+  `git branch --edit-description`, you will end up with a 0/N mail with that description and
+  a nice overall diffstat.
+* `--in-reply-to=[Message-ID]`: This will mark your cover letter as replying to the given
+  message (which should correspond to your previous iteration). To determine the correct Message-ID,
+  find the message you are replying to on [public-inbox.org/git](https://public-inbox.org/git) and take
+  the ID from between the angle brackets.
+
+* `--subject-prefix=[prefix]`: This defaults to [PATCH]. For subsequent iterations, you will want to
+  override it like `--subject-prefix="[PATCH v2]"`.  You can also use the `-v` option to have it
+  automatically generate the version number in the patches.
+
+If you have multiple commits and use the `--cover-letter` option be sure to open the
+`0000-cover-letter.patch` file to update the subject and add some details about the overall purpose
+of the patch series.
+
+### Examples
+
+To generate a single commit patch file:
+```
+git format-patch -s -o [dir] -1
+```
+To generate four patch files from the last three commits with a cover letter:
+```
+git format-patch --cover-letter -s -o [dir] HEAD~4
+```
+To generate version 3 with four patch files from the last four commits with a cover letter:
+```
+git format-patch --cover-letter -s -o [dir] -v 3 HEAD~4
+```
+
+### Submit the Patch
+
+Run [`git send-email`](https://git-scm.com/docs/git-send-email), starting with a test email:
+
+```
+git send-email --to=yourself@address.com  [dir with patches]/*.patch
+```
+
+After checking the receipt of your test email, you can send to the list and to any
+potentially interested reviewers.
+
+```
+git send-email --to=git@vger.kernel.org --cc=<email1> --cc=<email2> [dir with patches]/*.patch
+```
+
+To submit a nth version patch (say version 3):
+
+```
+git send-email --to=git@vger.kernel.org --cc=<email1> --cc=<email2> \
+    --in-reply-to=<the message id of cover letter of patch v2> [dir with patches]/*.patch
+```

From a34a4d3d7296538f73a34ff473a980374070d730 Mon Sep 17 00:00:00 2001
From: "Neeraj K. Singh" <neerajsi@microsoft.com>
Date: Wed, 27 Oct 2021 14:22:42 -0700
Subject: [PATCH 249/259] mingw: do not call xutftowcs_path in mingw_mktemp

The `xutftowcs_path` function canonicalizes absolute paths using GetFullPathNameW.
This canonicalization may change the length of the string (e.g. getting rid of \.\),
which breaks callers that pass the template string in a strbuf and expect the
length of the string to remain the same.

In my particular case, the tmp-objdir code is passing a strbuf to mkdtemp and is
breaking since the strbuf.len is no longer synchronized with strlen(strbuf.buf).

Signed-off-by: Neeraj K. Singh <neerajsi@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index 4626f98e522058..c077bfb9a48043 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1276,8 +1276,11 @@ char *mingw_mktemp(char *template)
 	int offset = 0;
 
 	/* we need to return the path, thus no long paths here! */
-	if (xutftowcs_path(wtemplate, template) < 0)
+	if (xutftowcsn(wtemplate, template, MAX_PATH, -1) < 0) {
+		if (errno == ERANGE)
+			errno = ENAMETOOLONG;
 		return NULL;
+	}
 
 	if (is_dir_sep(template[0]) && !is_dir_sep(template[1]) &&
 	    iswalpha(wtemplate[0]) && wtemplate[1] == L':') {

From 778b3f0feebae6e86ff6f05847e0daa8f4421198 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 25 Nov 2021 11:26:41 +0100
Subject: [PATCH 250/259] Partially un-revert "editor: save and reset terminal
 after calling EDITOR"

In e3f7e01b50be (Revert "editor: save and reset terminal after calling
EDITOR", 2021-11-22), we reverted the commit wholesale where the
terminal state would be saved and restored before/after calling an
editor.

The reverted commit was intended to fix a problem with Windows Terminal
where simply calling `vi` would cause problems afterwards.

To fix the problem addressed by the revert, but _still_ keep the problem
with Windows Terminal fixed, let's revert the revert, with a twist: we
restrict the save/restore _specifically_ to the case where `vi` (or
`vim`) is called, and do not do the same for any other editor.

This should still catch the majority of the cases, and will bridge the
time until the original patch is re-done in a way that addresses all
concerns.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 editor.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/editor.c b/editor.c
index d1ba2d7c34fbf4..e46b5af9ab8236 100644
--- a/editor.c
+++ b/editor.c
@@ -11,6 +11,7 @@
 #include "strvec.h"
 #include "run-command.h"
 #include "sigchain.h"
+#include "compat/terminal.h"
 
 #ifndef DEFAULT_EDITOR
 #define DEFAULT_EDITOR "vi"
@@ -62,6 +63,7 @@ static int launch_specified_editor(const char *editor, const char *path,
 		return error("Terminal is dumb, but EDITOR unset");
 
 	if (strcmp(editor, ":")) {
+		int save_and_restore_term = !strcmp(editor, "vi") || !strcmp(editor, "vim");
 		struct strbuf realpath = STRBUF_INIT;
 		struct child_process p = CHILD_PROCESS_INIT;
 		int ret, sig;
@@ -90,7 +92,11 @@ static int launch_specified_editor(const char *editor, const char *path,
 			strvec_pushv(&p.env, (const char **)env);
 		p.use_shell = 1;
 		p.trace2_child_class = "editor";
+		if (save_and_restore_term)
+			save_and_restore_term = !save_term(1);
 		if (start_command(&p) < 0) {
+			if (save_and_restore_term)
+				restore_term();
 			strbuf_release(&realpath);
 			return error("unable to start editor '%s'", editor);
 		}
@@ -98,6 +104,8 @@ static int launch_specified_editor(const char *editor, const char *path,
 		sigchain_push(SIGINT, SIG_IGN);
 		sigchain_push(SIGQUIT, SIG_IGN);
 		ret = finish_command(&p);
+		if (save_and_restore_term)
+			restore_term();
 		strbuf_release(&realpath);
 		sig = ret - 128;
 		sigchain_pop(SIGINT);

From aed93ffe56833530e624b86b999908b6bbcf7a8a Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 10 Dec 2019 21:41:57 +0100
Subject: [PATCH 251/259] reset: reinstate support for the deprecated --stdin
 option

The `--stdin` option was a well-established paradigm in other commands,
therefore we implemented it in `git reset` for use by Visual Studio.

Unfortunately, upstream Git decided that it is time to introduce
`--pathspec-from-file` instead.

To keep backwards-compatibility for some grace period, we therefore
reinstate the `--stdin` option on top of the `--pathspec-from-file`
option, but mark it firmly as deprecated.

Helped-by: Victoria Dye <vdye@github.com>
Helped-by: Matthew John Cheetham <mjcheetham@outlook.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 Documentation/git-reset.txt | 11 +++++++++++
 builtin/reset.c             | 16 ++++++++++++++++
 t/t7108-reset-stdin.sh      | 32 ++++++++++++++++++++++++++++++++
 3 files changed, 59 insertions(+)
 create mode 100755 t/t7108-reset-stdin.sh

diff --git a/Documentation/git-reset.txt b/Documentation/git-reset.txt
index 79ad5643eedb82..94fed757630f51 100644
--- a/Documentation/git-reset.txt
+++ b/Documentation/git-reset.txt
@@ -12,6 +12,7 @@ SYNOPSIS
 'git reset' [-q] [--pathspec-from-file=<file> [--pathspec-file-nul]] [<tree-ish>]
 'git reset' (--patch | -p) [<tree-ish>] [--] [<pathspec>...]
 'git reset' [--soft | --mixed [-N] | --hard | --merge | --keep] [-q] [<commit>]
+DEPRECATED: 'git reset' [-q] [--stdin [-z]] [<tree-ish>]
 
 DESCRIPTION
 -----------
@@ -133,6 +134,16 @@ OPTIONS
 +
 For more details, see the 'pathspec' entry in linkgit:gitglossary[7].
 
+--stdin::
+	DEPRECATED (use `--pathspec-from-file=-` instead): Instead of taking
+	list of paths from the command line, read list of paths from the
+	standard input. Paths are separated by LF (i.e. one path per line) by
+	default.
+
+-z::
+	DEPRECATED (use `--pathspec-file-nul` instead): Only meaningful with
+	`--stdin`; paths are separated with NUL character instead of LF.
+
 EXAMPLES
 --------
 
diff --git a/builtin/reset.c b/builtin/reset.c
index 5f941fb3a29cce..9cba244fb045d0 100644
--- a/builtin/reset.c
+++ b/builtin/reset.c
@@ -35,6 +35,8 @@
 #include "trace2.h"
 #include "dir.h"
 #include "add-interactive.h"
+#include "strbuf.h"
+#include "quote.h"
 
 #define REFRESH_INDEX_DELAY_WARNING_IN_MS (2 * 1000)
 
@@ -43,6 +45,7 @@ static const char * const git_reset_usage[] = {
 	N_("git reset [-q] [<tree-ish>] [--] <pathspec>..."),
 	N_("git reset [-q] [--pathspec-from-file [--pathspec-file-nul]] [<tree-ish>]"),
 	N_("git reset --patch [<tree-ish>] [--] [<pathspec>...]"),
+	N_("DEPRECATED: git reset [-q] [--stdin [-z]] [<tree-ish>]"),
 	NULL
 };
 
@@ -340,6 +343,7 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 	struct object_id oid;
 	struct pathspec pathspec;
 	int intent_to_add = 0;
+	int nul_term_line = 0, read_from_stdin = 0;
 	const struct option options[] = {
 		OPT__QUIET(&quiet, N_("be quiet, only report errors")),
 		OPT_BOOL(0, "no-refresh", &no_refresh,
@@ -368,6 +372,10 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 				N_("record only the fact that removed paths will be added later")),
 		OPT_PATHSPEC_FROM_FILE(&pathspec_from_file),
 		OPT_PATHSPEC_FILE_NUL(&pathspec_file_nul),
+		OPT_BOOL('z', NULL, &nul_term_line,
+			N_("DEPRECATED (use --pathspec-file-nul instead): paths are separated with NUL character")),
+		OPT_BOOL(0, "stdin", &read_from_stdin,
+				N_("DEPRECATED (use --pathspec-from-file=- instead): read paths from <stdin>")),
 		OPT_END()
 	};
 
@@ -377,6 +385,14 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 						PARSE_OPT_KEEP_DASHDASH);
 	parse_args(&pathspec, argv, prefix, patch_mode, &rev);
 
+	if (read_from_stdin) {
+		warning(_("--stdin is deprecated, please use --pathspec-from-file=- instead"));
+		free(pathspec_from_file);
+		pathspec_from_file = xstrdup("-");
+		if (nul_term_line)
+			pathspec_file_nul = 1;
+	}
+
 	if (pathspec_from_file) {
 		if (patch_mode)
 			die(_("options '%s' and '%s' cannot be used together"), "--pathspec-from-file", "--patch");
diff --git a/t/t7108-reset-stdin.sh b/t/t7108-reset-stdin.sh
new file mode 100755
index 00000000000000..b7cbcbf869296c
--- /dev/null
+++ b/t/t7108-reset-stdin.sh
@@ -0,0 +1,32 @@
+#!/bin/sh
+
+test_description='reset --stdin'
+
+. ./test-lib.sh
+
+test_expect_success 'reset --stdin' '
+	test_commit hello &&
+	git rm hello.t &&
+	test -z "$(git ls-files hello.t)" &&
+	echo hello.t | git reset --stdin &&
+	test hello.t = "$(git ls-files hello.t)"
+'
+
+test_expect_success 'reset --stdin -z' '
+	test_commit world &&
+	git rm hello.t world.t &&
+	test -z "$(git ls-files hello.t world.t)" &&
+	printf world.tQworld.tQhello.tQ | q_to_nul | git reset --stdin -z &&
+	printf "hello.t\nworld.t\n" >expect &&
+	git ls-files >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success '--stdin requires --mixed' '
+	echo hello.t >list &&
+	test_must_fail git reset --soft --stdin <list &&
+	test_must_fail git reset --hard --stdin <list &&
+	git reset --mixed --stdin <list
+'
+
+test_done

From c841d6e73033309dc19a5c6d02d826cedecc29f7 Mon Sep 17 00:00:00 2001
From: Victoria Dye <vdye@github.com>
Date: Mon, 4 Apr 2022 15:38:58 -0700
Subject: [PATCH 252/259] fsmonitor: reintroduce core.useBuiltinFSMonitor

Reintroduce the 'core.useBuiltinFSMonitor' config setting (originally added
in 0a756b2a25 (fsmonitor: config settings are repository-specific,
2021-03-05)) after its removal from the upstream version of FSMonitor.

Upstream, the 'core.useBuiltinFSMonitor' setting was rendered obsolete by
"overloading" the 'core.fsmonitor' setting to take a boolean value. However,
several applications (e.g., 'scalar') utilize the original config setting,
so it should be preserved for a deprecation period before complete removal:

* if 'core.fsmonitor' is a boolean, the user is correctly using the new
  config syntax; do not use 'core.useBuiltinFSMonitor'.
* if 'core.fsmonitor' is unspecified, use 'core.useBuiltinFSMonitor'.
* if 'core.fsmonitor' is a path, override and use the builtin FSMonitor if
  'core.useBuiltinFSMonitor' is 'true'; otherwise, use the FSMonitor hook
  indicated by the path.

Additionally, for this deprecation period, advise users to switch to using
'core.fsmonitor' to specify their use of the builtin FSMonitor.

Signed-off-by: Victoria Dye <vdye@github.com>
---
 Documentation/config/advice.txt |  4 ++++
 advice.c                        |  1 +
 advice.h                        |  1 +
 fsmonitor-settings.c            | 34 +++++++++++++++++++++++++++++++--
 4 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/Documentation/config/advice.txt b/Documentation/config/advice.txt
index 0ba89898207f0c..86bf99d55c6575 100644
--- a/Documentation/config/advice.txt
+++ b/Documentation/config/advice.txt
@@ -160,4 +160,8 @@ advice.*::
 		Shown when the user tries to create a worktree from an
 		invalid reference, to tell the user how to create a new unborn
 		branch instead.
+
+	useCoreFSMonitorConfig::
+		Advice shown if the deprecated 'core.useBuiltinFSMonitor' config
+		setting is in use.
 --
diff --git a/advice.c b/advice.c
index 6b879d805c0304..66f196e0ae3cd9 100644
--- a/advice.c
+++ b/advice.c
@@ -87,6 +87,7 @@ static struct {
 	[ADVICE_SUBMODULE_MERGE_CONFLICT]               = { "submoduleMergeConflict" },
 	[ADVICE_SUGGEST_DETACHING_HEAD]			= { "suggestDetachingHead" },
 	[ADVICE_UPDATE_SPARSE_PATH]			= { "updateSparsePath" },
+	[ADVICE_USE_CORE_FSMONITOR_CONFIG]		= { "useCoreFSMonitorConfig" },
 	[ADVICE_WAITING_FOR_EDITOR]			= { "waitingForEditor" },
 	[ADVICE_WORKTREE_ADD_ORPHAN]			= { "worktreeAddOrphan" },
 };
diff --git a/advice.h b/advice.h
index d7466bc0ef2026..a78ea909ed8e7f 100644
--- a/advice.h
+++ b/advice.h
@@ -54,6 +54,7 @@ enum advice_type {
 	ADVICE_SUBMODULE_MERGE_CONFLICT,
 	ADVICE_SUGGEST_DETACHING_HEAD,
 	ADVICE_UPDATE_SPARSE_PATH,
+	ADVICE_USE_CORE_FSMONITOR_CONFIG,
 	ADVICE_WAITING_FOR_EDITOR,
 	ADVICE_WORKTREE_ADD_ORPHAN,
 };
diff --git a/fsmonitor-settings.c b/fsmonitor-settings.c
index e818583420aa1b..7ce048c4efed5d 100644
--- a/fsmonitor-settings.c
+++ b/fsmonitor-settings.c
@@ -5,6 +5,7 @@
 #include "fsmonitor-ipc.h"
 #include "fsmonitor-settings.h"
 #include "fsmonitor-path-utils.h"
+#include "advice.h"
 
 /*
  * We keep this structure defintion private and have getters
@@ -100,6 +101,31 @@ static struct fsmonitor_settings *alloc_settings(void)
 	return s;
 }
 
+static int check_deprecated_builtin_config(struct repository *r)
+{
+	int core_use_builtin_fsmonitor = 0;
+
+	/*
+	 * If 'core.useBuiltinFSMonitor' is set, print a deprecation warning
+	 * suggesting the use of 'core.fsmonitor' instead. If the config is
+	 * set to true, set the appropriate mode and return 1 indicating that
+	 * the check resulted the config being set by this (deprecated) setting.
+	 */
+	if(!repo_config_get_bool(r, "core.useBuiltinFSMonitor", &core_use_builtin_fsmonitor) &&
+	   core_use_builtin_fsmonitor) {
+		if (!git_env_bool("GIT_SUPPRESS_USEBUILTINFSMONITOR_ADVICE", 0)) {
+			advise_if_enabled(ADVICE_USE_CORE_FSMONITOR_CONFIG,
+					  _("core.useBuiltinFSMonitor=true is deprecated;"
+					    "please set core.fsmonitor=true instead"));
+			setenv("GIT_SUPPRESS_USEBUILTINFSMONITOR_ADVICE", "1", 1);
+		}
+		fsm_settings__set_ipc(r);
+		return 1;
+	}
+
+	return 0;
+}
+
 static void lookup_fsmonitor_settings(struct repository *r)
 {
 	const char *const_str;
@@ -126,12 +152,16 @@ static void lookup_fsmonitor_settings(struct repository *r)
 		return;
 
 	case 1: /* config value was unset */
+		if (check_deprecated_builtin_config(r))
+			return;
+
 		const_str = getenv("GIT_TEST_FSMONITOR");
 		break;
 
 	case -1: /* config value set to an arbitrary string */
-		if (repo_config_get_pathname(r, "core.fsmonitor", &to_free))
-			return; /* should not happen */
+		if (check_deprecated_builtin_config(r) ||
+		    repo_config_get_pathname(r, "core.fsmonitor", &to_free))
+			return;
 		const_str = to_free;
 		break;
 

From 12224bb1da8448933789a21e1a7364660b4015cc Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 6 Feb 2024 18:45:35 +0100
Subject: [PATCH 253/259] dependabot: help keeping GitHub Actions versions up
 to date

See https://docs.github.com/en/code-security/dependabot/working-with-dependabot/keeping-your-actions-up-to-date-with-dependabot#enabling-dependabot-version-updates-for-actions for details.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 .github/dependabot.yml | 13 +++++++++++++
 1 file changed, 13 insertions(+)
 create mode 100644 .github/dependabot.yml

diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 00000000000000..22d5376407abf1
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,13 @@
+# To get started with Dependabot version updates, you'll need to specify which
+# package ecosystems to update and where the package manifests are located.
+# Please see the documentation for all configuration options:
+# https://docs.github.com/code-security/dependabot/dependabot-version-updates/configuration-options-for-the-dependabot.yml-file
+# especially
+# https://docs.github.com/en/code-security/dependabot/working-with-dependabot/keeping-your-actions-up-to-date-with-dependabot#enabling-dependabot-version-updates-for-actions
+
+version: 2
+updates:
+  - package-ecosystem: "github-actions" # See documentation for possible values
+    directory: "/" # Location of package manifests
+    schedule:
+      interval: "weekly"

From 89a6099681690824f6e5231be11c30ce7f873448 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 10 Jan 2014 16:16:03 -0600
Subject: [PATCH 254/259] README.md: Add a Windows-specific preamble
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Includes touch-ups by 마누엘, Philip Oakley and 孙卓识.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 README.md | 78 +++++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 76 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 665ce5f5a83647..4eabce53d89e1f 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,77 @@
-[![Build status](https://github.com/git/git/workflows/CI/badge.svg)](https://github.com/git/git/actions?query=branch%3Amaster+event%3Apush)
+Git for Windows
+===============
+
+[![Contributor Covenant](https://img.shields.io/badge/Contributor%20Covenant-2.1-4baaaa.svg)](CODE_OF_CONDUCT.md)
+[![Open in Visual Studio Code](https://img.shields.io/static/v1?logo=visualstudiocode&label=&message=Open%20in%20Visual%20Studio%20Code&labelColor=2c2c32&color=007acc&logoColor=007acc)](https://open.vscode.dev/git-for-windows/git)
+[![Build status](https://github.com/git-for-windows/git/workflows/CI/badge.svg)](https://github.com/git-for-windows/git/actions?query=branch%3Amain+event%3Apush)
+[![Join the chat at https://gitter.im/git-for-windows/git](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/git-for-windows/git?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
+
+This is [Git for Windows](http://git-for-windows.github.io/), the Windows port
+of [Git](http://git-scm.com/).
+
+The Git for Windows project is run using a [governance
+model](http://git-for-windows.github.io/governance-model.html). If you
+encounter problems, you can report them as [GitHub
+issues](https://github.com/git-for-windows/git/issues), discuss them on Git
+for Windows' [Google Group](http://groups.google.com/group/git-for-windows),
+and [contribute bug
+fixes](https://github.com/git-for-windows/git/wiki/How-to-participate).
+
+To build Git for Windows, please either install [Git for Windows'
+SDK](https://gitforwindows.org/#download-sdk), start its `git-bash.exe`, `cd`
+to your Git worktree and run `make`, or open the Git worktree as a folder in
+Visual Studio.
+
+To verify that your build works, use one of the following methods:
+
+- If you want to test the built executables within Git for Windows' SDK,
+  prepend `<worktree>/bin-wrappers` to the `PATH`.
+- Alternatively, run `make install` in the Git worktree.
+- If you need to test this in a full installer, run `sdk build
+  git-and-installer`.
+- You can also "install" Git into an existing portable Git via `make install
+  DESTDIR=<dir>` where `<dir>` refers to the top-level directory of the
+  portable Git. In this instance, you will want to prepend that portable Git's
+  `/cmd` directory to the `PATH`, or test by running that portable Git's
+  `git-bash.exe` or `git-cmd.exe`.
+- If you built using a recent Visual Studio, you can use the menu item
+  `Build>Install git` (you will want to click on `Project>CMake Settings for
+  Git` first, then click on `Edit JSON` and then point `installRoot` to the
+  `mingw64` directory of an already-unpacked portable Git).
+
+  As in the previous  bullet point, you will then prepend `/cmd` to the `PATH`
+  or run using the portable Git's `git-bash.exe` or `git-cmd.exe`.
+- If you want to run the built executables in-place, but in a CMD instead of
+  inside a Bash, you can run a snippet like this in the `git-bash.exe` window
+  where Git was built (ensure that the `EOF` line has no leading spaces), and
+  then paste into the CMD window what was put in the clipboard:
+
+  ```sh
+  clip.exe <<EOF
+  set GIT_EXEC_PATH=$(cygpath -aw .)
+  set PATH=$(cygpath -awp ".:contrib/scalar:/mingw64/bin:/usr/bin:$PATH")
+  set GIT_TEMPLATE_DIR=$(cygpath -aw templates/blt)
+  set GITPERLLIB=$(cygpath -aw perl/build/lib)
+  EOF
+  ```
+- If you want to run the built executables in-place, but outside of Git for
+  Windows' SDK, and without an option to set/override any environment
+  variables (e.g. in Visual Studio's debugger), you can call the Git executable
+  by its absolute path and use the `--exec-path` option, like so:
+
+  ```cmd
+  C:\git-sdk-64\usr\src\git\git.exe --exec-path=C:\git-sdk-64\usr\src\git help
+  ```
+
+  Note: for this to work, you have to hard-link (or copy) the `.dll` files from
+  the `/mingw64/bin` directory to the Git worktree, or add the `/mingw64/bin`
+  directory to the `PATH` somehow or other.
+
+To make sure that you are testing the correct binary, call `./git.exe version`
+in the Git worktree, and then call `git version` in a directory/window where
+you want to test Git, and verify that they refer to the same version (you may
+even want to pass the command-line option `--build-options` to look at the
+exact commit from which the Git version was built).
 
 Git - fast, scalable, distributed revision control system
 =========================================================
@@ -29,7 +102,7 @@ CVS users may also want to read [Documentation/gitcvs-migration.txt][]
 (`man gitcvs-migration` or `git help cvs-migration` if git is
 installed).
 
-The user discussion and development of Git take place on the Git
+The user discussion and development of core Git take place on the Git
 mailing list -- everyone is welcome to post bug reports, feature
 requests, comments and patches to git@vger.kernel.org (read
 [Documentation/SubmittingPatches][] for instructions on patch submission
@@ -43,6 +116,7 @@ To subscribe to the list, send an email to <git+subscribe@vger.kernel.org>
 (see https://subspace.kernel.org/subscribing.html for details). The mailing
 list archives are available at <https://lore.kernel.org/git/>,
 <https://marc.info/?l=git> and other archival sites.
+The core git mailing list is plain text (no HTML!).
 
 Issues which are security relevant should be disclosed privately to
 the Git Security mailing list <git-security@googlegroups.com>.

From 2a5e47a06079f31b9909840c33e1e1bbc1444650 Mon Sep 17 00:00:00 2001
From: Brendan Forster <brendan@github.com>
Date: Thu, 18 Feb 2016 21:29:50 +1100
Subject: [PATCH 255/259] Add an issue template

With improvements by Clive Chan, Adric Norris, Ben Bodenmiller and
Philip Oakley.

Helped-by: Clive Chan <cc@clive.io>
Helped-by: Adric Norris <landstander668@gmail.com>
Helped-by: Ben Bodenmiller <bbodenmiller@hotmail.com>
Helped-by: Philip Oakley <philipoakley@iee.org>
Signed-off-by: Brendan Forster <brendan@github.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 .github/ISSUE_TEMPLATE.md | 64 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 64 insertions(+)
 create mode 100644 .github/ISSUE_TEMPLATE.md

diff --git a/.github/ISSUE_TEMPLATE.md b/.github/ISSUE_TEMPLATE.md
new file mode 100644
index 00000000000000..4017ed82ca4341
--- /dev/null
+++ b/.github/ISSUE_TEMPLATE.md
@@ -0,0 +1,64 @@
+ - [ ] I was not able to find an [open](https://github.com/git-for-windows/git/issues?q=is%3Aopen) or [closed](https://github.com/git-for-windows/git/issues?q=is%3Aclosed) issue matching what I'm seeing
+
+### Setup
+
+ - Which version of Git for Windows are you using? Is it 32-bit or 64-bit?
+
+```
+$ git --version --build-options
+
+** insert your machine's response here **
+```
+
+ - Which version of Windows are you running? Vista, 7, 8, 10? Is it 32-bit or 64-bit?
+
+```
+$ cmd.exe /c ver
+
+** insert your machine's response here **
+```
+
+ - What options did you set as part of the installation? Or did you choose the
+   defaults?
+
+```
+# One of the following:
+> type "C:\Program Files\Git\etc\install-options.txt"
+> type "C:\Program Files (x86)\Git\etc\install-options.txt"
+> type "%USERPROFILE%\AppData\Local\Programs\Git\etc\install-options.txt"
+> type "$env:USERPROFILE\AppData\Local\Programs\Git\etc\install-options.txt"
+$ cat /etc/install-options.txt
+
+** insert your machine's response here **
+```
+
+ - Any other interesting things about your environment that might be related
+   to the issue you're seeing?
+
+** insert your response here **
+
+### Details
+
+ - Which terminal/shell are you running Git from? e.g Bash/CMD/PowerShell/other
+
+** insert your response here **
+
+ - What commands did you run to trigger this issue? If you can provide a
+   [Minimal, Complete, and Verifiable example](http://stackoverflow.com/help/mcve)
+   this will help us understand the issue.
+
+```
+** insert your commands here **
+```
+ - What did you expect to occur after running these commands?
+
+** insert here **
+
+ - What actually happened instead?
+
+** insert here **
+
+ - If the problem was occurring with a specific repository, can you provide the
+   URL to that repository to help us with testing?
+
+** insert URL here **

From 8a0c0696c5608ff9ac93daa62efb68f204a36974 Mon Sep 17 00:00:00 2001
From: Philip Oakley <philipoakley@iee.org>
Date: Fri, 22 Dec 2017 17:15:50 +0000
Subject: [PATCH 256/259] Modify the GitHub Pull Request template (to reflect
 Git for Windows)

Git for Windows accepts pull requests; Core Git does not. Therefore we
need to adjust the template (because it only matches core Git's
project management style, not ours).

Also: direct Git for Windows enhancements to their contributions page,
space out the text for easy reading, and clarify that the mailing list
is plain text, not HTML.

Signed-off-by: Philip Oakley <philipoakley@iee.org>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 .github/PULL_REQUEST_TEMPLATE.md | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/.github/PULL_REQUEST_TEMPLATE.md b/.github/PULL_REQUEST_TEMPLATE.md
index 37654cdfd7abcf..7baf31f2c471ec 100644
--- a/.github/PULL_REQUEST_TEMPLATE.md
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -1,7 +1,19 @@
-Thanks for taking the time to contribute to Git! Please be advised that the
-Git community does not use github.com for their contributions. Instead, we use
-a mailing list (git@vger.kernel.org) for code submissions, code reviews, and
-bug reports. Nevertheless, you can use GitGitGadget (https://gitgitgadget.github.io/)
+Thanks for taking the time to contribute to Git!
+
+Those seeking to contribute to the Git for Windows fork should see
+http://gitforwindows.org/#contribute on how to contribute Windows specific
+enhancements.
+
+If your contribution is for the core Git functions and documentation
+please be aware that the Git community does not use the github.com issues
+or pull request mechanism for their contributions.
+
+Instead, we use the Git mailing list (git@vger.kernel.org) for code and
+documentation submissions, code reviews, and bug reports. The
+mailing list is plain text only (anything with HTML is sent directly
+to the spam folder).
+
+Nevertheless, you can use GitGitGadget (https://gitgitgadget.github.io/)
 to conveniently send your Pull Requests commits to our mailing list.
 
 For a single-commit pull request, please *leave the pull request description

From 526471d45d91fc3b3d38a8740f2f3f2636e9aab2 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 20 Feb 2018 15:44:57 +0100
Subject: [PATCH 257/259] .github: Add configuration for the Sentiment Bot

The sentiment bot will help detect when things get too heated.
Hopefully.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 .github/config.yml | 10 ++++++++++
 1 file changed, 10 insertions(+)
 create mode 100644 .github/config.yml

diff --git a/.github/config.yml b/.github/config.yml
new file mode 100644
index 00000000000000..45edb7ba37ce02
--- /dev/null
+++ b/.github/config.yml
@@ -0,0 +1,10 @@
+# Configuration for sentiment-bot - https://github.com/behaviorbot/sentiment-bot
+
+# *Required* toxicity threshold between 0 and .99 with the higher numbers being
+# the most toxic. Anything higher than this threshold will be marked as toxic
+# and commented on
+sentimentBotToxicityThreshold: .7
+
+# *Required* Comment to reply with
+sentimentBotReplyComment: >
+  Please be sure to review the code of conduct and be respectful of other users. cc/ @git-for-windows/trusted-git-for-windows-developers

From e2b472d169ceebf8b073ea04a550bdf67b276cab Mon Sep 17 00:00:00 2001
From: Alejandro Barreto <alejandro.barreto@ni.com>
Date: Fri, 9 Mar 2018 14:17:54 -0600
Subject: [PATCH 258/259] Document how $HOME is set on Windows

Git documentation refers to $HOME and $XDG_CONFIG_HOME often, but does not specify how or where these values come from on Windows where neither is set by default. The new documentation reflects the behavior of setup_windows_environment() in compat/mingw.c.

Signed-off-by: Alejandro Barreto <alejandro.barreto@ni.com>
---
 Documentation/git.txt | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/git.txt b/Documentation/git.txt
index 4489e2297a396b..74ee8334cfdfd0 100644
--- a/Documentation/git.txt
+++ b/Documentation/git.txt
@@ -477,6 +477,14 @@ their values the same way as Boolean valued configuration variables, e.g.
 
 Here are the variables:
 
+System
+~~~~~~
+`HOME`::
+	Specifies the path to the user's home directory. On Windows, if
+	unset, Git will set a process environment variable equal to:
+	`$HOMEDRIVE$HOMEPATH` if both `$HOMEDRIVE` and `$HOMEPATH` exist;
+	otherwise `$USERPROFILE` if `$USERPROFILE` exists.
+
 The Git Repository
 ~~~~~~~~~~~~~~~~~~
 These environment variables apply to 'all' core Git commands. Nb: it

From d726d6ca0ee3a69b8f717be9c47e05eba76d67c7 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 23 Aug 2019 14:14:42 +0200
Subject: [PATCH 259/259] SECURITY.md: document Git for Windows' policies

This is the recommended way on GitHub to describe policies revolving around
security issues and about supported versions.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 SECURITY.md | 56 +++++++++++++++++++++++++++++++++--------------------
 1 file changed, 35 insertions(+), 21 deletions(-)

diff --git a/SECURITY.md b/SECURITY.md
index c720c2ae7f9580..328351684298a4 100644
--- a/SECURITY.md
+++ b/SECURITY.md
@@ -28,24 +28,38 @@ Examples for details to include:
 
 ## Supported Versions
 
-There are no official "Long Term Support" versions in Git.
-Instead, the maintenance track (i.e. the versions based on the
-most recently published feature release, also known as ".0"
-version) sees occasional updates with bug fixes.
-
-Fixes to vulnerabilities are made for the maintenance track for
-the latest feature release and merged up to the in-development
-branches. The Git project makes no formal guarantee for any
-older maintenance tracks to receive updates. In practice,
-though, critical vulnerability fixes are applied not only to the
-most recent track, but to at least a couple more maintenance
-tracks.
-
-This is typically done by making the fix on the oldest and still
-relevant maintenance track, and merging it upwards to newer and
-newer maintenance tracks.
-
-For example, v2.24.1 was released to address a couple of
-[CVEs](https://cve.mitre.org/), and at the same time v2.14.6,
-v2.15.4, v2.16.6, v2.17.3, v2.18.2, v2.19.3, v2.20.2, v2.21.1,
-v2.22.2 and v2.23.1 were released.
+Git for Windows is a "friendly fork" of [Git](https://git-scm.com/), i.e. changes in Git for Windows are frequently contributed back, and Git for Windows' release cycle closely following Git's.
+
+While Git maintains several release trains (when v2.19.1 was released, there were updates to v2.14.x-v2.18.x, too, for example), Git for Windows follows only the latest Git release. For example, there is no Git for Windows release corresponding to Git v2.16.5 (which was released after v2.19.0).
+
+One exception is [MinGit for Windows](https://github.com/git-for-windows/git/wiki/MinGit) (a minimal subset of Git for Windows, intended for bundling with third-party applications that do not need any interactive commands nor support for `git svn`): critical security fixes are backported to the v2.11.x, v2.14.x, v2.19.x, v2.21.x and v2.23.x release trains.
+
+## Version number scheme
+
+The Git for Windows versions reflect the Git version on which they are based. For example, Git for Windows v2.21.0 is based on Git v2.21.0.
+
+As Git for Windows bundles more than just Git (such as Bash, OpenSSL, OpenSSH, GNU Privacy Guard), sometimes there are interim releases without corresponding Git releases. In these cases, Git for Windows appends a number in parentheses, starting with the number 2, then 3, etc. For example, both Git for Windows v2.17.1 and v2.17.1(2) were based on Git v2.17.1, but the latter included updates for Git Credential Manager and Git LFS, fixing critical regressions.
+
+## Tag naming scheme
+
+Every Git for Windows version is tagged using a name that starts with the Git version on which it is based, with the suffix `.windows.<patchlevel>` appended. For example, Git for Windows v2.17.1' source code is tagged as [`v2.17.1.windows.1`](https://github.com/git-for-windows/git/releases/tag/v2.17.1.windows.1) (the patch level is always at least 1, given that Git for Windows always has patches on top of Git). Likewise, Git for Windows v2.17.1(2)' source code is tagged as [`v2.17.1.windows.2`](https://github.com/git-for-windows/git/releases/tag/v2.17.1.windows.2).
+
+## Release Candidate (rc) versions
+
+As a friendly fork of Git (the "upstream" project), Git for Windows is closely corelated to that project.
+
+Consequently, Git for Windows publishes versions based on Git's release candidates (for upcoming "`.0`" versions, see [Git's release schedule](https://tinyurl.com/gitCal)). These versions end in `-rc<n>`, starting with `-rc0` for a very early preview of what is to come, and as with regular versions, Git for Windows tries to follow Git's releases as quickly as possible.
+
+Note: there is currently a bug in the "Check daily for updates" code, where it mistakes the final version as a downgrade from release candidates. Example: if you installed Git for Windows v2.23.0-rc3 and enabled the auto-updater, it would ask you whether you want to "downgrade" to v2.23.0 when that version was available.
+
+[All releases](https://github.com/git-for-windows/git/releases/), including release candidates, are listed via a link at the footer of the [Git for Windows](https://gitforwindows.org/) home page.
+
+## Snapshot versions ('nightly builds')
+
+Git for Windows also provides snapshots (these are not releases) of the the current development as per git-for-Windows/git's `master` branch at the [Snapshots](https://wingit.blob.core.windows.net/files/index.html) page. This link is also listed in the footer of the [Git for Windows](https://gitforwindows.org/) home page.
+
+Note: even if those builds are not exactly "nightly", they are sometimes referred to as "nightly builds" to keep with other projects' nomenclature.
+
+## Following upstream's developments
+
+The [gitforwindows/git repository](https://github.com/git-for-windows/git) also provides the `shears/*` branches. The `shears/*` branches reflect Git for Windows' patches, rebased onto the upstream integration branches, [updated (mostly) via automated CI builds](https://dev.azure.com/git-for-windows/git/_build?definitionId=25).