Issue #5669: Advance NULL Pointers #5793
Merged
Conversation
This file contains 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
added 3 commits
December 23, 2022 20:10
The comparators wre not advancing pointers when two NULL elements of a struct compared as equal, causing the rest of the scan to be misaligned. Test coming but the repro case was very nasty.
Fun test case that took me ~8 hours to generate...
|
fixes #5669 |
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Outdated suggestions cannot be applied.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.
The comparators were not advancing pointers
when two NULL elements of a struct compared as equal,
causing the rest of the scan to be misaligned.
The test case (that took me ~8 hours to generate...)
had to have the same layout as the original data
but be obfuscated, hence the rather nasty example.
The Window operator was an innocent bystander here -
the bug is in the comparison logic when comparing two complex,
identical
structs from the original data set that got unnestedinto duplicates and then sorted. Since they were equal, the entire
data structure had to be scanned, but once the pointers became
misaligned, it took a while for something bad to actually happen.