[test-suite][lemon] Avoid UB in hash computations by using unsigned a… #280
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
…rithmetic UBSan reports signed overflow in several hash computations in MultiSource/Applications/lemon/lemon.c: - strhash: h = h*13 + *x (line ~4174) - statehash: h = h*571 + a->rp->index*37 + a->dot (line ~4557) - confighash: h = h*571 + a->rp->index*37 + a->dot (line ~4715) - datatype hash: hash = hash*53 + stddt[j] (line ~3409) These use intentional wraparound, but signed overflow is undefined in C. Switch accumulators to unsigned and use unsigned operations so wraparound is well-defined. No functional change is intended beyond removing UB. Signed-off-by: Jerry Zhang Jian <[email protected]>
nikic
reviewed
Aug 29, 2025
| @@ -1238,14 +1238,14 @@ struct lemon *lemp; | |||
|
|
|||
| /* Sort the configuration list */ | |||
| void Configlist_sort(){ | |||
| current = (struct config *)msort((char *)current,(char **)&(current->next),Configcmp); | |||
| current = (struct config *)msort((char *)current,(char **)&(current->next),(int(*)(const char*,const char*))Configcmp); | |||
There was a problem hiding this comment.
Complete the declaration instead of adding casts?
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Outdated suggestions cannot be applied.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.
…rithmetic
UBSan reports signed overflow in several hash computations in MultiSource/Applications/lemon/lemon.c:
These use intentional wraparound, but signed overflow is undefined in C. Switch accumulators to unsigned and use unsigned operations so wraparound is well-defined. No functional change is intended beyond removing UB.