Bug#1118446: freecad: Freecad segfault on creating mesh from body

[Tobias Frost]

Control: tags -1 moreinfo

Hi Mike,

I can't reproduce the issue, can you elaborate how you get the crash?
(I've tried on a Body -> Mesh Workbench -> Meshed -> Create Mesh From
Shape while having a Body, and a second try reproduce a feature of the
Body, selected.

Can you share your model that is causing the crash?

-- 
tobi

On Mon, 20 Oct 2025 10:45:04 +0200 Michele Cane <michele.cane at gmail.com>
wrote:
> Package: freecad
> Version: 1.0.2+dfsg-2
> Severity: normal
> 
> Dear Maintainer,
> 
> When creating a mesh from a body or sets of bodies, FreeCAD segfaults
with the below back trace.
> 
> The issue does not arrise with AppImage 1.0.2 or 1.1.0dev (latest).
> 
> Best regards
> 
> Mike
> 
> [tempestus:17713:0:17713] Caught signal 11 (Segmentation fault:
address not mapped to object at address (nil))
> ==== backtrace (tid:  17713) ====
>  0  /lib/x86_64-linux-gnu/libucs.so.0(ucs_handle_error+0x2bc)
[0x7f17000b071c]
>  1  /lib/x86_64-linux-gnu/libucs.so.0(+0x328fd) [0x7f17000b08fd]
>  2  /lib/x86_64-linux-gnu/libucs.so.0(+0x32aca) [0x7f17000b0aca]
>  3  /lib/x86_64-linux-gnu/libc.so.6(+0x3fdf0) [0x7f17dbc49df0]
>  4  /lib/x86_64-linux-
gnu/libnglib.so.6.2(_ZNK6netgen11OCCGeometry7GetEdgeERK12TopoDS_Shape+0x
4a) [0x7f16f0e903ea]
>  5  /lib/x86_64-linux-
gnu/libnglib.so.6.2(_ZN6netgen19OCCSetLocalMeshSizeERKNS_11OCCGeometryER
NS_4MeshERKNS_17MeshingParametersERKNS_13OCCParametersE+0x1055)
[0x7f16f0e86c75]
>  6  /lib/x86_64-linux-
gnu/libnglib.so.6.2(_ZN6netgen14NetgenGeometry12GenerateMeshERSt10shared
_ptrINS_4MeshEERNS_17MeshingParametersE+0x3b4) [0x7f16f0d7c774]
>  7  /usr/lib/freecad-
python3/lib/libNETGENPlugin.so(_ZN6netgen15OCCGenerateMeshERNS_11OCCGeom
etryERSt10shared_ptrINS_4MeshEERNS_17MeshingParametersE+0x2b)
[0x7f174844f31b]
>  8  /usr/lib/freecad-
python3/lib/libNETGENPlugin.so(_ZN19NETGENPlugin_Mesher7ComputeEv+0x363)
[0x7f1748444b33]
>  9  /usr/lib/freecad-
python3/lib/libNETGENPlugin.so(_ZN22NETGENPlugin_NETGEN_2D7ComputeER10SM
ESH_MeshRK12TopoDS_Shape+0xb3) [0x7f174844ddf3]
> 10  /usr/lib/freecad-
python3/lib/libSMESH.so(_ZN13SMESH_subMesh18ComputeStateEngineEi+0xaf8)
[0x7f16f165d238]
> 11  /usr/lib/freecad-
python3/lib/libSMESH.so(_ZN9SMESH_Gen7ComputeER10SMESH_MeshRK12TopoDS_Sh
apebb13MeshDimensionPSt3setIiSt4lessIiESaIiEE+0x7e6) [0x7f16f159af26]
> 12  /usr/lib/freecad-
python3/lib/MeshPart.so(_ZNK8MeshPart6Mesher10createMeshEv+0x13b)
[0x7f17488e9bab]
> 13  /usr/lib/freecad-python3/lib/MeshPart.so(+0x367fa)
[0x7f17488c37fa]
> 14  /usr/lib/freecad-
python3/lib/MeshPart.so(_ZN8MeshPart6Module13meshFromShapeERKN2Py5TupleE
RKNS1_4DictE+0xfa4) [0x7f17488c7c64]
> 15  /usr/lib/freecad-
python3/lib/MeshPart.so(_ZN2Py15ExtensionModuleIN8MeshPart6ModuleEE21inv
oke_method_keywordEPvRKNS_5TupleERKNS_4DictE+0x3c) [0x7f17488c2f6c]
> 16  /usr/lib/freecad-
python3/lib/libFreeCADBase.so(method_keyword_call_handler+0x219)
[0x7f17de0efc89]
> 17  /lib/x86_64-linux-gnu/libpython3.13.so.1.0(+0x172102)
[0x7f17dd972102]
> 18  /lib/x86_64-linux-
gnu/libpython3.13.so.1.0(_PyObject_MakeTpCall+0x19a) [0x7f17dd914c9a]
> 19  /lib/x86_64-linux-
gnu/libpython3.13.so.1.0(_PyEval_EvalFrameDefault+0x28ee)
[0x7f17dda573ce]
> 20  /lib/x86_64-linux-gnu/libpython3.13.so.1.0(PyEval_EvalCode+0xe0)
[0x7f17dda54a00]
> 21  /lib/x86_64-linux-gnu/libpython3.13.so.1.0(+0x2ddaaa)
[0x7f17ddaddaaa]
> 22  /lib/x86_64-linux-gnu/libpython3.13.so.1.0(+0x2dde49)
[0x7f17ddadde49]
> 23  /lib/x86_64-linux-gnu/libpython3.13.so.1.0(PyRun_StringFlags+0x75)
[0x7f17ddade8d5]
> 24  /usr/lib/freecad-
python3/lib/libFreeCADBase.so(_ZN4Base20InterpreterSingleton9runStringB5
cxx11EPKc+0x6a) [0x7f17de156fca]
> 25  /usr/lib/freecad-
python3/lib/libFreeCADGui.so(_ZN3Gui7Command11_runCommandEPKciNS0_10DoCm
d_TypeES2_+0x96) [0x7f17df2f8626]
> 26  /usr/lib/freecad-
python3/lib/MeshPartGui.so(_ZN11MeshPartGui12Tessellation7processEiPN3Ap
p8DocumentERKNSt7__cxx114listINS1_10SubObjectTESaIS6_EEE+0x2d1)
[0x7f174854a3b1]
> 27  /usr/lib/freecad-
python3/lib/MeshPartGui.so(_ZN11MeshPartGui12Tessellation6acceptEv+0x2f4
) [0x7f174854ac64]
> 28  /usr/lib/freecad-
python3/lib/libFreeCADGui.so(_ZN3Gui8TaskView8TaskView6acceptEv+0x63)
[0x7f17df6e0873]
> 29  /lib/x86_64-linux-gnu/libQt5Core.so.5(+0x3256e9) [0x7f17dc5256e9]
> 30  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x30e6c8)
[0x7f17dd30e6c8]
> 31  /lib/x86_64-linux-gnu/libQt5Core.so.5(+0x3256bd) [0x7f17dc5256bd]
> 32  /lib/x86_64-linux-
gnu/libQt5Widgets.so.5(_ZN15QAbstractButton7clickedEb+0x46)
[0x7f17dd25e8d6]
> 33  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x25eb4e)
[0x7f17dd25eb4e]
> 34  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x2607af)
[0x7f17dd2607af]
> 35  /lib/x86_64-linux-
gnu/libQt5Widgets.so.5(_ZN15QAbstractButton17mouseReleaseEventEP11QMouse
Event+0x129) [0x7f17dd2609d9]
> 36  /lib/x86_64-linux-
gnu/libQt5Widgets.so.5(_ZN7QWidget5eventEP6QEvent+0x308)
[0x7f17dd1a72d8]
> 37  /lib/x86_64-linux-
gnu/libQt5Widgets.so.5(_ZN19QApplicationPrivate13notify_helperEP7QObject
P6QEvent+0x80) [0x7f17dd164240]
> 38  /lib/x86_64-linux-
gnu/libQt5Widgets.so.5(_ZN12QApplication6notifyEP7QObjectP6QEvent+0x1351
) [0x7f17dd16bba1]
> 39  /usr/lib/freecad-
python3/lib/libFreeCADGui.so(_ZN3Gui14GUIApplication6notifyEP7QObjectP6Q
Event+0xc8) [0x7f17df29c6a8]
> 40  /lib/x86_64-linux-
gnu/libQt5Core.so.5(_ZN16QCoreApplication15notifyInternal2EP7QObjectP6QE
vent+0x128) [0x7f17dc4e94c8]
> 41  /lib/x86_64-linux-
gnu/libQt5Widgets.so.5(_ZN19QApplicationPrivate14sendMouseEventEP7QWidge
tP11QMouseEventS1_S1_PS1_R8QPointerIS0_Ebb+0x1c4) [0x7f17dd169c24]
> 42  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x1c1e2a)
[0x7f17dd1c1e2a]
> 43  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x1c52ff)
[0x7f17dd1c52ff]