IRGen: Don't hide noncopyable metadata from access functions in load-bearing mangled names. #84726
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
Contributor Author
| @swift-ci Please test |
jckarter force-pushed the dont-hide-load-bearing-noncopyable-metadata branch from 564e63c to 0e33fe1 Compare Contributor Author
| @swift-ci Please test |
mikeash approved these changes Oct 7, 2025
…bearing mangled names. There is a compatibility hack where fallback metadata access functions used in field type metadata lie and say a field's type is the empty tuple when it's noncopyable and the runtime doesn't advertise compatibility with noncopyable types. Unfortunately, this hack applied to *all* fallback metadata access functions, causing us to return wrong metadata in situations we really need the correct metadata, such as in associated type substitutions. Constrain the hack to only apply to reflection metadata. Fixes rdar://161562839.
jckarter force-pushed the dont-hide-load-bearing-noncopyable-metadata branch from 0e33fe1 to b4d7e98 Compare Contributor Author
| @swift-ci Please test |
Contributor Author
| @swift-ci Please test macOS |
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
2 participants
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 Outdated suggestions cannot be applied.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.
There is a compatibility hack where fallback metadata access functions used in field type metadata lie and say a field's type is the empty tuple when it's noncopyable and the runtime doesn't advertise compatibility with noncopyable types. Unfortunately, this hack applied to all fallback metadata access functions, causing us to return wrong metadata in situations we really need the correct metadata, such as in associated type substitutions. Constrain the hack to only apply to reflection metadata. Fixes rdar://161562839.