[5.3] IRGen: Correctly compute the offset for a non-fixed field after… #31924
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
… an empty field Introduce getByteOffsetDuringLayout() so that we can treat empty fields just like other fixed sized field while performing layout. Explanation: We used to incorrectly compute the offset of a non-fixed field after an empty field inside of a closure capture context. This lead to crashes at runtime because we read memory that the wrong offset. Scope: Causes Swift programs that caputre empty fields and non-fixed fields to crash or misbehave. Risk: Medium, we now correctly compute the offset in such cases. Testing: Regression test added. Reviewer: Slava Pestov rdar://62349871
|
@swift-ci Please test |
|
Original PR: #31863 |
tkremenek
approved these changes
May 20, 2020
AnthonyLatsis
added
swift 5.3
🍒 release cherry pick
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Outdated suggestions cannot be applied.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.
… an empty field
Introduce getByteOffsetDuringLayout() so that we can treat empty fields
just like other fixed sized field while performing layout.
Explanation: We used to incorrectly compute the offset of a non-fixed
field after an empty field inside of a closure capture context. This lead to
crashes at runtime because we read memory that the wrong offset.
Scope: Causes Swift programs that caputre empty fields and non-fixed
fields to crash or misbehave.
Risk: Medium, we now correctly compute the offset in such cases.
Testing: Regression test added.
Reviewer: Slava Pestov
rdar://62349871