[5.1][Runtime] Fix swift_conformsToProtocol crashing on conformances to unavailable classes. #26649
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
…available classes. An extension on a class creates a conformance record that's always visible even when that class is not present at runtime. In that case, the type pointer in the conformance record is NULL. The runtime did not like this, and crashed. This fixes it to ignore such records instead. rdar://problem/54054895
Add code to the 5.0 compatibility library that scans for conformances pointing to a NULL type and rewrites them to point to a dummy type that the 5.0 protocol conformance checking code will safely ignore.
|
@swift-ci please test |
|
Build failed |
|
@swift-ci please test |
|
Build failed |
|
Build failed |
airspeedswift
approved these changes
Aug 14, 2019
|
@swift-ci test |
|
Build failed |
|
Build failed |
mikeash
force-pushed
the
fix-protocol-conformances-on-unavailable-classes-5.1
branch
from
8815ac0 to
7ca665b
Compare
|
@swift-ci please test |
|
Build failed |
|
Build failed |
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Outdated suggestions cannot be applied.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.
Cherry-pick #26638 to 5.1.
An extension on a class creates a conformance record that's always visible even when that class is not present at runtime. In that case, the type pointer in the conformance record is NULL. The runtime did not like this, and crashed. This fixes it to ignore such records instead.
For back deployment to Swift 5.0, the swiftCompatibility50 library is extended to find conformance records with NULL type pointers and rewrite those pointers to point to a dummy type that will be ignored by the runtime.
rdar://problem/54054895