Sketcher: Fix crash when applying constraints during selection batching#26741
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chennes merged 1 commit intoFreeCAD:mainfrom Jan 8, 2026
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Currently, the selection batching optimization introduced in FreeCAD#26663 stores ElementItem/ConstraintItem pointers in a buffer to be processed on the next event loop cycle via `QTimer::singleShot`. When a constraint is applied, `slotElementsChanged()/slotConstraintsChanged()` rebuilds the list widget, destroying all items. However, the selection buffer was not cleared, leaving dangling pointers. When `processSelectionBuffer()` executed, it attempted to call `QListWidget::row()` on deleted items, causing a segmentation fault. So, this patch fixes it by clearing `selectionBuffer` when the list is rebuilt, since the buffered pointers are invalidated anyway.
maxwxyz
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Type: Bug
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Thanks for the catch @tetektoza ! |
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Successfully created backport PR for |
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Currently, the selection batching optimization introduced in #26663 stores ElementItem/ConstraintItem pointers in a buffer to be processed on the next event loop cycle via
QTimer::singleShot.When a constraint is applied,
slotElementsChanged()/slotConstraintsChanged()rebuilds the list widget, destroying all items. However, the selection buffer was not cleared, leaving dangling pointers. When
processSelectionBuffer()executed, it attempted to callQListWidget::row()on deleted items, causing a segmentation fault.So, this patch fixes it by clearing
selectionBufferwhen the list is rebuilt, since the buffered pointers are invalidated anyway.Would you be able to check @PaddleStroke?
Demo: nothing to show, was crashing, doesn't crash now. At least on my Debian machine.
Resolves: #26734