GH-51018: [C++] Fix indices_nonzero segfault on chunkless ChunkedArray - #51021
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waterWang wants to merge 1 commit into
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GH-51018: [C++] Fix indices_nonzero segfault on chunkless ChunkedArray#51021waterWang wants to merge 1 commit into
waterWang wants to merge 1 commit into
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…edArray Calling indices_nonzero on a ChunkedArray with zero chunks (e.g. the shape produced by filtering a table down to no rows) segfaulted. IndicesNonZeroExecChunked built an empty vector of ArraySpans, and DoNonZero unconditionally dereferenced arrays[0].type, performing an out-of-bounds vector access. Guard DoNonZero so an empty chunk vector yields an empty result, consistent with the zero-length Array and single-empty-chunk cases.
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Rationale for this change
pyarrow.compute.indices_nonzero()segfaults (SIGSEGV) on aChunkedArraywith zero chunks — the shape produced by filtering a table to no rows or
slicing zero rows. Reproduced on pyarrow 18.1.0 through 25.0.1. A zero-length
Arrayand aChunkedArrayholding one empty chunk both work; only thechunkless case crashes.
What changes are included in this PR?
IndicesNonZeroExecChunkedbuilds astd::vector<ArraySpan>from the chunks;for a zero-chunk array that vector is empty.
DoNonZerounconditionallydereferenced
arrays[0].type, an out-of-bounds vector access. GuardDoNonZeroso an empty chunk vector returns an empty result, consistent with the other
empty-input paths.
Are these changes tested?
Yes — added a zero-chunk case to
TestIndicesNonZero.IndicesNonZerothatasserts
indices_nonzeroonChunkedArray({}, type)returns[]for everynumeric type. The crash reproduces locally on pyarrow 25.0.1 (SIGSEGV); with
the fix the same call returns an empty array.