From 4ecabc61b15d944438d404fb755609705def249f Mon Sep 17 00:00:00 2001
From: Mads Marquart <mads@marquart.dk>
Date: Sun, 7 Jan 2024 10:56:43 +0100
Subject: [PATCH] Ensure no block ABI types have trailing padding

---
 crates/block2/src/abi.rs | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/crates/block2/src/abi.rs b/crates/block2/src/abi.rs
index 87bd0e147..0ea8549c5 100644
--- a/crates/block2/src/abi.rs
+++ b/crates/block2/src/abi.rs
@@ -296,3 +296,26 @@ pub(crate) struct BlockDescriptorCopyDisposeSignature {
     #[doc(alias = "signature")]
     pub(crate) encoding: *const c_char,
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn assert_no_trailing_padding<T>() {
+        struct AddU8<T> {
+            t: T,
+            extra: u8,
+        }
+        assert_ne!(core::mem::size_of::<T>(), core::mem::size_of::<AddU8<T>>());
+    }
+
+    #[test]
+    fn no_types_have_padding() {
+        assert_no_trailing_padding::<BlockHeader>();
+        assert_no_trailing_padding::<BlockDescriptorPtr>();
+        assert_no_trailing_padding::<BlockDescriptor>();
+        assert_no_trailing_padding::<BlockDescriptorCopyDispose>();
+        assert_no_trailing_padding::<BlockDescriptorSignature>();
+        assert_no_trailing_padding::<BlockDescriptorCopyDisposeSignature>();
+    }
+}