Avoid invalidating @_objcImplementation #76270
Merged
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
beccadax
force-pushed
the
objcimpl-serialization-2
branch
from
60d73cc to
e94a057
Compare
|
Revised the implementation—the original one would sometimes cause two diagnostics to be emitted on the same declaration. This wouldn't block a build that wasn't already being blocked, but it would make the developer experience worse. |
In swiftlang#69257, we modified `ObjCReason` to carry a pointer to the @implementation attribute for the `MemberOfObjCImplementationExtension` kind. This made it mark the @implementation attribute as invalid, suppressing diagnostics from the ObjCImplementationChecker. However, invalidating the attribute *also* causes it to be skipped by serialization. That isn’t a problem if the diagnostics are errors, since we’ll never emit the serialized module, but swiftlang#74135 softened these diagnostics to warnings for early adopters. The upshot was that if Swift emitted one of these warnings when it compiled a library, clients of that library would see the objcImpl extension as a normal extension instead. This would cause various kinds of mischief: ambiguous name lookups because implementations weren’t being excluded, overrides failing because an implementation was `public` instead of `open`, asserts and crashes in SILGen and IRGen because stored properties were found in seemingly normal extensions, etc. Fix this by setting a separate bit on ObjCImplementationAttr, rather than the invalid bit, and modifying the implementation checker to manually suppress many diagnostics when that bit is set. Fixes rdar://134730183.
beccadax
force-pushed
the
objcimpl-serialization-2
branch
from
e94a057 to
94ec99c
Compare
|
@swift-ci please test |
beccadax
changed the title
beccadax
requested review from
hborla,
slavapestov,
xymus and
xedin
as code owners
tshortli
approved these changes
Sep 9, 2024
| // expected-warning@-1 {{method cannot be in an @objc @implementation extension of a class (without final or @nonobjc) because the type of the parameter cannot be represented in Objective-C}} | ||
|
|
||
| // CHECK-DAG: @objc func goodMethod() | ||
| @objc public func goodMethod() {} |
There was a problem hiding this comment.
Not a blocker, but it would be nice if this test also demonstrated end-to-end that a client can also deserialize and use the emitted module here, since that's where the failure manifested IIUC.
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.
In #69257, we modified
ObjCReasonto carry a pointer to the @implementation attribute for theMemberOfObjCImplementationExtensionkind. This made it mark the @implementation attribute as invalid, suppressing diagnostics from the ObjCImplementationChecker.However, invalidating the attribute also causes it to be skipped by serialization. That isn’t a problem if the diagnostics are errors, since we’ll never emit the serialized module, but #74135 softened these diagnostics to warnings for early adopters.
The upshot was that if Swift emitted one of these warnings when it compiled a library, clients of that library would see the objcImpl extension as a normal extension instead. This would cause various kinds of mischief: ambiguous name lookups because implementations weren’t being excluded, overrides failing because an implementation was
publicinstead ofopen, asserts and crashes in SILGen and IRGen because stored properties were found in seemingly normal extensions, etc.Fix this by setting a separate bit on ObjCImplementationAttr, rather than the invalid bit, and modifying the implementation checker to manually suppress many diagnostics when that bit is set.
Fixes rdar://134730183.