Add -emit-public-type-metadata-accessors to work around metadata linkage bug. #16616
Conversation
This file contains 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
…age bug. IRGen can introduce calls to type metadata accessors for types that should not be visible to the current translate, which can manifest in linker errors within a module (for references to private types when whole module optimization is disabled) or across modules (for references to private/internal types in another module). Introduce a new compiler flag `-emit-public-type-metadata-accessors` that emits all type metadata accessors with public linkage, to work around the problem in affected projects. This flag is intended to go away once we have a proper solution. This bug has been around in Swift "forever", but compiling the overlays using -enable-resilience has exacerbated the problem and caused regressions. This is a short-term fix to rdar://problem/40229755 while we work on the correct long-term fix.
|
@swift-ci please smoke test |
|
Note that the long-term solution is #16615. |
|
Adding this to the project in https://bugs.swift.org/browse/SR-7549 fixes (ahem, works around) the crash there. |
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Outdated suggestions cannot be applied.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.
IRGen can introduce calls to type metadata accessors for types that
should not be visible to the current translate, which can manifest in
linker errors within a module (for references to private types when
whole module optimization is disabled) or across modules (for
references to private/internal types in another module). Introduce a
new compiler flag
-emit-public-type-metadata-accessorsthat emitsall type metadata accessors with public linkage, to work around the
problem in affected projects. This flag is intended to go away once we
have a proper solution.
This bug has been around in Swift "forever", but compiling the
overlays using -enable-resilience has exacerbated the problem and
caused regressions. This is a short-term fix to
rdar://problem/40229755 while we work on the correct long-term fix.