fix alignment of guard blocks#4137
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dnovillo merged 2 commits intoKhronosGroup:mainfrom Mar 20, 2026
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Thanks! LGTM.
I'll merge this after tests finish.
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the
GUARD_BLOCKSfeature that is enabled whenNDEBUGis not specified can cause unaligned memory allocations. This was causing Emscripten debug builds to throw alignment faults when-sSAFE_HEAP=2, and causing Safari to leak large amounts of memory when safe heap was disabled.this change simply fixes the guard block size logic to ensure the combined header+guard size is 16-byte aligned which I believe was the intention.
Also, I realize the leak claim sounds crazy, and if true is clearly a safari bug, but fixing alignment issue is still a good idea. Also here is a simple repro.