u3: fix return type in hashtable trim when missing key#995
Open
u3: fix return type in hashtable trim when missing key#995
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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 PR fixes a bug in hashtable trimming (introduced while refactoring in 98bcfaa). The wrong sentinel value was returned for a missing key in an intermediate node (
c3ninstead ofu3_none), making it appear incorrectly that a value had been trimmed and causing the hashtable entry-count to be wrongly decremented. This was effectively a space leak in the capped-cache variants of our HAMTs (ie, the persistent memoization cache), corrected only by melding.