[release/8.0-staging] [mono] Workaround MSVC miscompiling sgen_clz #114904
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After the recent VS upgrade from 17.12.5 to 17.13.2 we started seeing access violations in the mono-aot-cross.exe when targetting wasm. We tracked it down to sgen_clz being miscompiled, we can workaround the compiler bug by switching from ternary condition to if/else.
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Apr 22, 2025
This was referenced Apr 22, 2025
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No-op change to workaround compiler bug, tell mode, applying servicing-approved. |
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Backport of #114786 to release/8.0-staging
/cc @akoeplinger
Customer Impact
Newer version of MSVC miscompiles a certain function in the mono runtime, leading to crashes.
Regression
Yes, due to infrastructure update bringing in new VS/MSVC.
Testing
Manual testing.
Risk
Low, this is a no-op change to workaround a compiler bug.