Cleanup internal ComWrappers cache when object enters Finalization queue #52771
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Failure is #52710 |
elinor-fung
reviewed
May 25, 2021
elinor-fung
approved these changes
May 25, 2021
is an option remove the use of Detach in the IsActive logic and narrow its use to the cache cleanup scenario only.
ghost
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The
ComWrappersAPI has a deficiency/race during native object wrapper (RCW) cleanup. This is rare but has been observed in tight loops with complex object types. The scenario occurs when native object A is freed, its memory is reused for native object B, and that memory is provided back to the runtime but the previous mapping remains to the wrapper for native object A. The issue occurs based on an incorrect expectation between when the RCW's Finalizer will run and when the mapping between nativeIUnknown*to RCW will be removed from the internal cache.The solution is to remove the mapping when the RCW itself is scheduled for Finalization.
The issue was reported at microsoft/CsWinRT#762.
Additional issues
Fixes #53160