[clang][DependencyFile] Use atomic write for dependency file #10902
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
Previously when switch to output backend, dependency file was relying on non-atomic write + discard to remove the out of date dependency file when there are missing headers. This makes the write non-atomic and can cause races conditions that build system is trying to read the file while the file is being updated by a different compiler instance. rdar://154128578
|
@swift-ci please test llvm |
benlangmuir
approved these changes
Jun 26, 2025
Message is updated. |
cachemeifyoucan
added a commit
to cachemeifyoucan/llvm-project
that referenced
this pull request
Jun 26, 2025
…ng#10902) Previously when switch to output backend, dependency file was relying on non-atomic write + discard to remove the out of date dependency file when there are missing headers. The reliance on non-atomic write can cause race conditions that build system is trying to read the file while the file is being updated by a different compiler instance. rdar://154128578
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Outdated suggestions cannot be applied.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.
Previously when switch to output backend, dependency file was relying on non-atomic write + discard to remove the out of date dependency file when there are missing headers. The reliance on non-atomic write can cause races conditions that build system is trying to read the file while the file is being updated by a different compiler instance.
rdar://154128578