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Fix segfault when computing filter_geom() cubes - #1
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NewGraphEnvironment merged 2 commits intoSep 1, 2026
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filter_geom_cube::read_chunk() assigned a stack-allocated
OGRSpatialReference to the chunk polygon via assignSpatialReference(),
which takes refcounted ownership: ~OGRGeometry() calls Release() on the
SRS, and under GDAL 3 (pimpl'd OGRSpatialReference) the stack object is
destroyed before the polygon at every scope exit, so the release writes
through a dangling pointer. Every computed filter_geom() cube crashed
the worker process with SIGSEGV ("invalid permissions", fault address =
offsetof of the refcount inside GDAL's private SRS struct: 0x120 on GDAL
3.8.5, 0x138 on 3.13.3). Drop the assignment: Contains()/Intersects()
do not use the SRS, and both geometries are already in the cube CRS.
Also close out the log-and-continue error paths in the same code:
- GetDriverByName("GPKG") null check before Create() (constructor)
- GetNextFeature() null check before dereferencing the feature
- GDALRasterize() failure now throws instead of falling through to a
null GetRasterBand() dereference
- RasterIO() failure now throws instead of reading an uninitialized
mask buffer
Fixes appelmar#110
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01ENJ9rVrvd9BrixVKtgWtPu
Covers the segfault fixed in the previous commit (appelmar#110): computes a filter_geom() cube from a dummy cube via as_array(), asserting the exact burned-cell count, inside/outside values, and that the mask is identical under 50x50 chunking (exercising the chunk-within-polygon copy fast path). filter_geom() previously had no tests. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01ENJ9rVrvd9BrixVKtgWtPu
NewGraphEnvironment
deleted the
110-segfault-in-filter-geom-on-compute
branch
September 1, 2026 03:45
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Summary
filter_geom()cube (upstream Segfault in filter_geom() on compute (0.7.4, macOS arm64) appelmar/gdalcubes#110):read_chunk()handed a stack-allocatedOGRSpatialReferencetoOGRPolygon::assignSpatialReference(), which takes refcounted ownership andRelease()s it in~OGRGeometry()— a use-after-destruction under GDAL 3's pimpl'd SRS. The SRS assignment is dropped;Contains()/Intersects()never use it and both geometries are already in the cube CRS.filter_geom.cppwith proper throws:GetDriverByName("GPKG"),GetNextFeature(),GDALRasterize()(was a latent second null-deref segfault), andRasterIO()(was silently reading an uninitialized mask buffer).inst/tinytest/test_filter_geom.R—filter_geom()previously had zero test coverage — asserting exact burned-cell count, inside/outside values, and chunk-layout invariance (exercises the chunk-within-polygon copy fast path).Related Issues
filter_geomon Windows appelmar/gdalcubes#82 (filter_geomempty results on Windows — same worker-process code path)Root cause evidence
offsetof(OGRSpatialReference::Private, nRefCount), which shifts with GDAL's private struct layout. TheassignSpatialReferencecall was the only one in the codebase, which is why onlyfilter_geom()crashed.Test plan
Notes
newgraph(org base branch), so the diff contains only the fix, NEWS entry, and test — suitable for porting upstream as-is.masterwas fast-forwarded to upstream v0.7.4 RC (2cc0d46) first; the 0.7.2 source no longer compiled against GDAL 3.13 and the issue is filed against 0.7.4.🤖 Generated with Claude Code
https://claude.ai/code/session_01ENJ9rVrvd9BrixVKtgWtPu