Fix ABI mismatch involving Sendable-refining protocols and deployment targets #76379
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
… targets A change to the way we determined whether a protocol conformance is "dependent" for marker protocols caused an ABI break for Sendable-refining protocols built with pre-6.0 Swift compilers. The fix for this issue (swiftlang#75769) gated the change on deployment target. The deployment target change fixed the original problem, then caused a related issue when a project mixes deployment targets (pre-6.0 and 6.0+) with non-resilient protocols. Rework the logic here to (1) look at the availability of the protocol rather than the deployment target, and (2) always use the more efficient (non-dependent) answer for non-resilient protocols. Fixes rdar://134953989.
Member
Author
|
@swift-ci please smoke test |
Member
Author
|
The change here to use availability is not strictly necessary, because it's acceptable for programs to be compiled with the dependent-conformance access pattern even if the protocol itself is non-dependent. It's also less optimal, because it prevents conformances tied to newer Swift runtimes (e.g., shipped in an OS with a 6.0 runtime) from being emitted as non-dependent. Closing this in favor of the narrower and more desirable change at #76380 |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
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Outdated suggestions cannot be applied.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.
A change to the way we determined whether a protocol conformance is "dependent" for marker protocols caused an ABI break for Sendable-refining protocols built with pre-6.0 Swift compilers. The fix for this issue (#75769) gated the change on deployment target.
The deployment target change fixed the original problem, then caused a related issue when a project mixes deployment targets (pre-6.0 and 6.0+) with non-resilient protocols. Rework the logic here to (1) look at the availability of the protocol rather than the deployment target, and (2) always use the more efficient (non-dependent) answer for non-resilient protocols.
Fixes rdar://134953989.