fix(arrow/array): Resize(0) on non-empty builder causes memory leak - #995
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serramatutu
marked this pull request as ready for review
July 24, 2026 11:29
serramatutu
changed the title
Append then Resize causes memory leak on numeric buildersResize(0) on non-empty builder causes memory leak
zeroshade
approved these changes
Jul 24, 2026
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Rationale for this change
I found a memory leak while working on the JSON nullable parity PR. It's triggered whenever a non-empty builder gets resized to zero.
This memory leak can be achieved with public APIs only (
AppendandResize), meaning it's an actual bug in the public API and not a misuse of internal APIs where I didn't check for an invariant.In the specific case of the JSON PR, whenever we found an error in the first row that would call
Resize(-1), which in turn callsResize(0)on all the previous fields, and the bug gets triggered.You can checkout to each commit to see the test failing then passing after the fix.
What changes are included in this PR?
minBuilderCapacitywhen callingResize()Are these changes tested?
Yes.
Are there any user-facing changes?
No.