From 7d766d88d54ce38b9ebc943aea78b95b0533983d Mon Sep 17 00:00:00 2001
From: Avik Pal <avikpal@mit.edu>
Date: Wed, 18 Oct 2023 17:02:10 -0400
Subject: [PATCH] Prevent KrylovJL use for RecursiveArrayTools

---
 Project.toml                             |  6 +++++-
 ext/LinearSolveRecursiveArrayToolsExt.jl | 12 ++++++++++++
 src/default.jl                           |  2 +-
 3 files changed, 18 insertions(+), 2 deletions(-)
 create mode 100644 ext/LinearSolveRecursiveArrayToolsExt.jl

diff --git a/Project.toml b/Project.toml
index 186db01b7..34e9bbea8 100644
--- a/Project.toml
+++ b/Project.toml
@@ -33,14 +33,15 @@ UnPack = "3a884ed6-31ef-47d7-9d2a-63182c4928ed"
 [weakdeps]
 BandedMatrices = "aae01518-5342-5314-be14-df237901396f"
 BlockDiagonals = "0a1fb500-61f7-11e9-3c65-f5ef3456f9f0"
-Enzyme = "7da242da-08ed-463a-9acd-ee780be4f1d9"
 CUDA = "052768ef-5323-5732-b1bb-66c8b64840ba"
+Enzyme = "7da242da-08ed-463a-9acd-ee780be4f1d9"
 HYPRE = "b5ffcf37-a2bd-41ab-a3da-4bd9bc8ad771"
 IterativeSolvers = "42fd0dbc-a981-5370-80f2-aaf504508153"
 KernelAbstractions = "63c18a36-062a-441e-b654-da1e3ab1ce7c"
 KrylovKit = "0b1a1467-8014-51b9-945f-bf0ae24f4b77"
 Metal = "dde4c033-4e86-420c-a63e-0dd931031962"
 Pardiso = "46dd5b70-b6fb-5a00-ae2d-e8fea33afaf2"
+RecursiveArrayTools = "731186ca-8d62-57ce-b412-fbd966d074cd"
 
 [extensions]
 LinearSolveBandedMatricesExt = "BandedMatrices"
@@ -53,6 +54,7 @@ LinearSolveKernelAbstractionsExt = "KernelAbstractions"
 LinearSolveKrylovKitExt = "KrylovKit"
 LinearSolveMetalExt = "Metal"
 LinearSolvePardisoExt = "Pardiso"
+LinearSolveRecursiveArrayToolsExt = "RecursiveArrayTools"
 
 [compat]
 ArrayInterface = "7.4.11"
@@ -72,6 +74,7 @@ Krylov = "0.9"
 KrylovKit = "0.5, 0.6"
 PrecompileTools = "1"
 Preferences = "1"
+RecursiveArrayTools = "2"
 RecursiveFactorization = "0.2.8"
 Reexport = "1"
 Requires = "1"
@@ -99,6 +102,7 @@ Metal = "dde4c033-4e86-420c-a63e-0dd931031962"
 MultiFloats = "bdf0d083-296b-4888-a5b6-7498122e68a5"
 Pkg = "44cfe95a-1eb2-52ea-b672-e2afdf69b78f"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
+RecursiveArrayTools = "731186ca-8d62-57ce-b412-fbd966d074cd"
 SafeTestsets = "1bc83da4-3b8d-516f-aca4-4fe02f6d838f"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
diff --git a/ext/LinearSolveRecursiveArrayToolsExt.jl b/ext/LinearSolveRecursiveArrayToolsExt.jl
new file mode 100644
index 000000000..98da9583c
--- /dev/null
+++ b/ext/LinearSolveRecursiveArrayToolsExt.jl
@@ -0,0 +1,12 @@
+module LinearSolveRecursiveArrayToolsExt
+
+using LinearSolve, RecursiveArrayTools
+import LinearSolve: init_cacheval
+
+# Krylov.jl tries to init with `ArrayPartition(undef, ...)`. Avoid hitting that!
+function init_cacheval(alg::LinearSolve.KrylovJL, A, b::ArrayPartition, u, Pl, Pr,
+    maxiters::Int, abstol, reltol, verbose::Bool, ::LinearSolve.OperatorAssumptions)
+    return nothing
+end
+
+end
diff --git a/src/default.jl b/src/default.jl
index 04d9e0229..509a14571 100644
--- a/src/default.jl
+++ b/src/default.jl
@@ -93,7 +93,7 @@ end
 end
 
 function defaultalg(A::GPUArraysCore.AbstractGPUArray, b, assump::OperatorAssumptions)
-    if assump.condition === OperatorConodition.IllConditioned || !assump.issq
+    if assump.condition === OperatorCondition.IllConditioned || !assump.issq
         DefaultLinearSolver(DefaultAlgorithmChoice.QRFactorization)
     else
         @static if VERSION >= v"1.8-"