Fix a debug assert firing with multiple supertypes - #2689
Merged
fitzgen merged 1 commit intoSep 29, 2026
Merged
Conversation
This commit fixes a debug-assert added in bytecodealliance#2652 which could erroneously fire. Notably the interning of rec groups is not written to handle multiple supertypes (as that's an invalid module anyway). I intended to debug-assert that this situation didn't arise within intern'ing under the (erroneous) assumption that such modules were already rejected during validation. Turns out the validation happened in a different order meaning that the assertion could indeed fire and just didn't with the tests included. This adds a small supertype-length check before interning to ensure that the phase there doesn't even see multiple supertypes.
fitzgen
approved these changes
Sep 29, 2026
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
This commit fixes a debug-assert added in #2652 which could erroneously fire. Notably the interning of rec groups is not written to handle multiple supertypes (as that's an invalid module anyway). I intended to debug-assert that this situation didn't arise within intern'ing under the (erroneous) assumption that such modules were already rejected during validation. Turns out the validation happened in a different order meaning that the assertion could indeed fire and just didn't with the tests included. This adds a small supertype-length check before interning to ensure that the phase there doesn't even see multiple supertypes.