[Threading] Fix C11 once implementation to not rely on lock recursion. #70767
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
The implementation mistakenly locked and unlocked the mutex in `helper.once_wait()`, which is only ever called from inside a region where the mutex is already locked. rdar://119739594
al45tair
added
🍒 release cherry pick
|
Explanation: The C11 support was developed originally with a shim implementation that wouldn't have picked this problem up (we were accidentally locking and unlocking the mutex twice for the |
|
@swift-ci Please test |
tbkka
approved these changes
Jan 8, 2024
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
The implementation mistakenly locked and unlocked the mutex in
helper.once_wait(), which is only ever called from inside a region where the mutex is already locked.rdar://119739594