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+0x4a) [0x7f16f0e903ea]
 5  /lib/x86_64-linux-gnu/libnglib.so.6.2(_ZN6netgen19OCCSetLocalMeshSizeERKNS_11OCCGeometryERNS_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_11OCCGeometryERSt10shared_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_2D7ComputeER10SMESH_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_Shapebb13MeshDimensionPSt3setIiSt4lessIiESaIiEE+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(_ZN8MeshPart6Module13meshFromShapeERKN2Py5TupleERKNS1_4DictE+0xfa4) [0x7f17488c7c64]
15  /usr/lib/freecad-python3/lib/MeshPart.so(_ZN2Py15ExtensionModuleIN8MeshPart6ModuleEE21invoke_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(_ZN4Base20InterpreterSingleton9runStringB5cxx11EPKc+0x6a) [0x7f17de156fca]
25  /usr/lib/freecad-python3/lib/libFreeCADGui.so(_ZN3Gui7Command11_runCommandEPKciNS0_10DoCmd_TypeES2_+0x96) [0x7f17df2f8626]
26  /usr/lib/freecad-python3/lib/MeshPartGui.so(_ZN11MeshPartGui12Tessellation7processEiPN3App8DocumentERKNSt7__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(_ZN15QAbstractButton17mouseReleaseEventEP11QMouseEvent+0x129) [0x7f17dd2609d9]
36  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(_ZN7QWidget5eventEP6QEvent+0x308) [0x7f17dd1a72d8]
37  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(_ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent+0x80) [0x7f17dd164240]
38  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(_ZN12QApplication6notifyEP7QObjectP6QEvent+0x1351) [0x7f17dd16bba1]
39  /usr/lib/freecad-python3/lib/libFreeCADGui.so(_ZN3Gui14GUIApplication6notifyEP7QObjectP6QEvent+0xc8) [0x7f17df29c6a8]
40  /lib/x86_64-linux-gnu/libQt5Core.so.5(_ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent+0x128) [0x7f17dc4e94c8]
41  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(_ZN19QApplicationPrivate14sendMouseEventEP7QWidgetP11QMouseEventS1_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]
44  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(_ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent+0x80) [0x7f17dd164240]
45  /usr/lib/freecad-python3/lib/libFreeCADGui.so(_ZN3Gui14GUIApplication6notifyEP7QObjectP6QEvent+0xc8) [0x7f17df29c6a8]
46  /lib/x86_64-linux-gnu/libQt5Core.so.5(_ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent+0x128) [0x7f17dc4e94c8]
47  /lib/x86_64-linux-gnu/libQt5Gui.so.5(_ZN22QGuiApplicationPrivate17processMouseEventEPN29QWindowSystemInterfacePrivate10MouseEventE+0xc53) [0x7f17dc9469f3]
48  /lib/x86_64-linux-gnu/libQt5Gui.so.5(_ZN22QWindowSystemInterface22sendWindowSystemEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE+0xab) [0x7f17dc9163fb]
49  /lib/x86_64-linux-gnu/libQt5WaylandClient.so.5(+0xb4ce4) [0x7f17d5c61ce4]
50  /lib/x86_64-linux-gnu/libglib-2.0.so.0(+0x5c6ae) [0x7f17da1006ae]
51  /lib/x86_64-linux-gnu/libglib-2.0.so.0(+0x5fa4f) [0x7f17da103a4f]
52  /lib/x86_64-linux-gnu/libglib-2.0.so.0(g_main_context_iteration+0x30) [0x7f17da1041d0]
53  /lib/x86_64-linux-gnu/libQt5Core.so.5(_ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE+0x4a) [0x7f17dc54770a]
54  /lib/x86_64-linux-gnu/libQt5Core.so.5(_ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE+0x11a) [0x7f17dc4e7dfa]
55  /lib/x86_64-linux-gnu/libQt5Core.so.5(_ZN16QCoreApplication4execEv+0x8f) [0x7f17dc4f09af]
56  /usr/lib/freecad-python3/lib/libFreeCADGui.so(_ZN3Gui11Application14runApplicationEv+0xbab) [0x7f17df1b0e9b]
57  freecad(+0x8dd9) [0x560f638cddd9]
58  /lib/x86_64-linux-gnu/libc.so.6(+0x29ca8) [0x7f17dbc33ca8]
59  /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0x85) [0x7f17dbc33d65]
60  freecad(+0x91d1) [0x560f638ce1d1]
=================================
Program received signal SIGSEGV, Segmentation fault.
#0  /lib/x86_64-linux-gnu/libc.so.6(+0x3fdf0) [0x7f17dbc49df0]
#1  0x7f16f0e903ea in netgen::OCCGeometry::GetEdge(TopoDS_Shape const&) const from /lib/x86_64-linux-gnu/libnglib.so.6.2+0x4a
#2  0x7f16f0e86c75 in netgen::OCCSetLocalMeshSize(netgen::OCCGeometry const&, netgen::Mesh&, netgen::MeshingParameters const&, netgen::OCCParameters const&) from /lib/x86_64-linux-gnu/libnglib.so.6.2+0x1055
#3  0x7f16f0d7c774 in netgen::NetgenGeometry::GenerateMesh(std::shared_ptr<netgen::Mesh>&, netgen::MeshingParameters&) from /lib/x86_64-linux-gnu/libnglib.so.6.2+0x3b4
#4  0x7f174844f31b in netgen::OCCGenerateMesh(netgen::OCCGeometry&, std::shared_ptr<netgen::Mesh>&, netgen::MeshingParameters&) from /usr/lib/freecad-python3/lib/libNETGENPlugin.so+0x2b
#5  0x7f1748444b33 in NETGENPlugin_Mesher::Compute() from /usr/lib/freecad-python3/lib/libNETGENPlugin.so+0x363
#6  0x7f174844ddf3 in NETGENPlugin_NETGEN_2D::Compute(SMESH_Mesh&, TopoDS_Shape const&) from /usr/lib/freecad-python3/lib/libNETGENPlugin.so+0xb3
#7  0x7f16f165d238 in SMESH_subMesh::ComputeStateEngine(int) from /usr/lib/freecad-python3/lib/libSMESH.so+0xaf8
#8  0x7f16f159af26 in SMESH_Gen::Compute(SMESH_Mesh&, TopoDS_Shape const&, bool, bool, MeshDimension, std::set<int, std::less<int>, std::allocator<int> >*) from /usr/lib/freecad-python3/lib/libSMESH.so+0x7e6
#9  0x7f17488e9bab in MeshPart::Mesher::createMesh() const from /usr/lib/freecad-python3/lib/MeshPart.so+0x13b
#10  /usr/lib/freecad-python3/lib/MeshPart.so(+0x367fa) [0x7f17488c37fa]
#11  0x7f17488c7c64 in MeshPart::Module::meshFromShape(Py::Tuple const&, Py::Dict const&) from /usr/lib/freecad-python3/lib/MeshPart.so+0xfa4
#12  0x7f17488c2f6c in Py::ExtensionModule<MeshPart::Module>::invoke_method_keyword(void*, Py::Tuple const&, Py::Dict const&) from /usr/lib/freecad-python3/lib/MeshPart.so+0x3c
#13  /usr/lib/freecad-python3/lib/libFreeCADBase.so(method_keyword_call_handler+0x219) [0x7f17de0efc89]
#14  /lib/x86_64-linux-gnu/libpython3.13.so.1.0(+0x172102) [0x7f17dd972102]
#15  /lib/x86_64-linux-gnu/libpython3.13.so.1.0(_PyObject_MakeTpCall+0x19a) [0x7f17dd914c9a]
#16  /lib/x86_64-linux-gnu/libpython3.13.so.1.0(_PyEval_EvalFrameDefault+0x28ee) [0x7f17dda573ce]
#17  /lib/x86_64-linux-gnu/libpython3.13.so.1.0(PyEval_EvalCode+0xe0) [0x7f17dda54a00]
#18  /lib/x86_64-linux-gnu/libpython3.13.so.1.0(+0x2ddaaa) [0x7f17ddaddaaa]
#19  /lib/x86_64-linux-gnu/libpython3.13.so.1.0(+0x2dde49) [0x7f17ddadde49]
#20  /lib/x86_64-linux-gnu/libpython3.13.so.1.0(PyRun_StringFlags+0x75) [0x7f17ddade8d5]
#21  0x7f17de156fca in Base::InterpreterSingleton::runString[abi:cxx11](char const*) from /usr/lib/freecad-python3/lib/libFreeCADBase.so+0x6a
#22  0x7f17df2f8626 in Gui::Command::_runCommand(char const*, int, Gui::Command::DoCmd_Type, char const*) from /usr/lib/freecad-python3/lib/libFreeCADGui.so+0x96
#23  0x7f174854a3b1 in MeshPartGui::Tessellation::process(int, App::Document*, std::__cxx11::list<App::SubObjectT, std::allocator<App::SubObjectT> > const&) from /usr/lib/freecad-python3/lib/MeshPartGui.so+0x2d1
#24  0x7f174854ac64 in MeshPartGui::Tessellation::accept() from /usr/lib/freecad-python3/lib/MeshPartGui.so+0x2f4
#25  0x7f17df6e0873 in Gui::TaskView::TaskView::accept() from /usr/lib/freecad-python3/lib/libFreeCADGui.so+0x63
#26  /lib/x86_64-linux-gnu/libQt5Core.so.5(+0x3256e9) [0x7f17dc5256e9]
#27  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x30e6c8) [0x7f17dd30e6c8]
#28  /lib/x86_64-linux-gnu/libQt5Core.so.5(+0x3256bd) [0x7f17dc5256bd]
#29  0x7f17dd25e8d6 in QAbstractButton::clicked(bool) from /lib/x86_64-linux-gnu/libQt5Widgets.so.5+0x46
#30  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x25eb4e) [0x7f17dd25eb4e]
#31  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x2607af) [0x7f17dd2607af]
#32  0x7f17dd2609d9 in QAbstractButton::mouseReleaseEvent(QMouseEvent*) from /lib/x86_64-linux-gnu/libQt5Widgets.so.5+0x129
#33  0x7f17dd1a72d8 in QWidget::event(QEvent*) from /lib/x86_64-linux-gnu/libQt5Widgets.so.5+0x308
#34  0x7f17dd164240 in QApplicationPrivate::notify_helper(QObject*, QEvent*) from /lib/x86_64-linux-gnu/libQt5Widgets.so.5+0x80
#35  0x7f17dd16bba1 in QApplication::notify(QObject*, QEvent*) from /lib/x86_64-linux-gnu/libQt5Widgets.so.5+0x1351
#36  0x7f17df29c6a8 in Gui::GUIApplication::notify(QObject*, QEvent*) from /usr/lib/freecad-python3/lib/libFreeCADGui.so+0xc8
#37  0x7f17dc4e94c8 in QCoreApplication::notifyInternal2(QObject*, QEvent*) from /lib/x86_64-linux-gnu/libQt5Core.so.5+0x128
#38  0x7f17dd169c24 in QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool, bool) from /lib/x86_64-linux-gnu/libQt5Widgets.so.5+0x1c4
#39  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x1c1e2a) [0x7f17dd1c1e2a]
#40  /lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x1c52ff) [0x7f17dd1c52ff]
#41  0x7f17dd164240 in QApplicationPrivate::notify_helper(QObject*, QEvent*) from /lib/x86_64-linux-gnu/libQt5Widgets.so.5+0x80
#42  0x7f17df29c6a8 in Gui::GUIApplication::notify(QObject*, QEvent*) from /usr/lib/freecad-python3/lib/libFreeCADGui.so+0xc8
#43  0x7f17dc4e94c8 in QCoreApplication::notifyInternal2(QObject*, QEvent*) from /lib/x86_64-linux-gnu/libQt5Core.so.5+0x128
#44  0x7f17dc9469f3 in QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent*) from /lib/x86_64-linux-gnu/libQt5Gui.so.5+0xc53
#45  0x7f17dc9163fb in QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) from /lib/x86_64-linux-gnu/libQt5Gui.so.5+0xab
#46  /lib/x86_64-linux-gnu/libQt5WaylandClient.so.5(+0xb4ce4) [0x7f17d5c61ce4]
#47  /lib/x86_64-linux-gnu/libglib-2.0.so.0(+0x5c6ae) [0x7f17da1006ae]
#48  /lib/x86_64-linux-gnu/libglib-2.0.so.0(+0x5fa4f) [0x7f17da103a4f]
#49  /lib/x86_64-linux-gnu/libglib-2.0.so.0(g_main_context_iteration+0x30) [0x7f17da1041d0]
#50  0x7f17dc54770a in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) from /lib/x86_64-linux-gnu/libQt5Core.so.5+0x4a
#51  0x7f17dc4e7dfa in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) from /lib/x86_64-linux-gnu/libQt5Core.so.5+0x11a
#52  0x7f17dc4f09af in QCoreApplication::exec() from /lib/x86_64-linux-gnu/libQt5Core.so.5+0x8f
#53  0x7f17df1b0e9b in Gui::Application::runApplication() from /usr/lib/freecad-python3/lib/libFreeCADGui.so+0xbab
#54  freecad(+0x8dd9) [0x560f638cddd9]
#55  /lib/x86_64-linux-gnu/libc.so.6(+0x29ca8) [0x7f17dbc33ca8]
#56  /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0x85) [0x7f17dbc33d65]
#57  freecad(+0x91d1) [0x560f638ce1d1]

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?
with the below back trace.
address not mapped to object at address (nil))
[0x7f17000b071c]
gnu/libnglib.so.6.2(_ZNK6netgen11OCCGeometry7GetEdgeERK12TopoDS_Shape+0x
4a) [0x7f16f0e903ea]
gnu/libnglib.so.6.2(_ZN6netgen19OCCSetLocalMeshSizeERKNS_11OCCGeometryER
NS_4MeshERKNS_17MeshingParametersERKNS_13OCCParametersE+0x1055)
[0x7f16f0e86c75]
gnu/libnglib.so.6.2(_ZN6netgen14NetgenGeometry12GenerateMeshERSt10shared
_ptrINS_4MeshEERNS_17MeshingParametersE+0x3b4) [0x7f16f0d7c774]
python3/lib/libNETGENPlugin.so(_ZN6netgen15OCCGenerateMeshERNS_11OCCGeom
etryERSt10shared_ptrINS_4MeshEERNS_17MeshingParametersE+0x2b)
[0x7f174844f31b]
python3/lib/libNETGENPlugin.so(_ZN19NETGENPlugin_Mesher7ComputeEv+0x363)
[0x7f1748444b33]
python3/lib/libNETGENPlugin.so(_ZN22NETGENPlugin_NETGEN_2D7ComputeER10SM
ESH_MeshRK12TopoDS_Shape+0xb3) [0x7f174844ddf3]
python3/lib/libSMESH.so(_ZN13SMESH_subMesh18ComputeStateEngineEi+0xaf8)
[0x7f16f165d238]
python3/lib/libSMESH.so(_ZN9SMESH_Gen7ComputeER10SMESH_MeshRK12TopoDS_Sh
apebb13MeshDimensionPSt3setIiSt4lessIiESaIiEE+0x7e6) [0x7f16f159af26]
python3/lib/MeshPart.so(_ZNK8MeshPart6Mesher10createMeshEv+0x13b)
[0x7f17488e9bab]
[0x7f17488c37fa]
python3/lib/MeshPart.so(_ZN8MeshPart6Module13meshFromShapeERKN2Py5TupleE
RKNS1_4DictE+0xfa4) [0x7f17488c7c64]
python3/lib/MeshPart.so(_ZN2Py15ExtensionModuleIN8MeshPart6ModuleEE21inv
oke_method_keywordEPvRKNS_5TupleERKNS_4DictE+0x3c) [0x7f17488c2f6c]
python3/lib/libFreeCADBase.so(method_keyword_call_handler+0x219)
[0x7f17de0efc89]
[0x7f17dd972102]
gnu/libpython3.13.so.1.0(_PyObject_MakeTpCall+0x19a) [0x7f17dd914c9a]
gnu/libpython3.13.so.1.0(_PyEval_EvalFrameDefault+0x28ee)
[0x7f17dda573ce]
[0x7f17dda54a00]
[0x7f17ddaddaaa]
[0x7f17ddadde49]
[0x7f17ddade8d5]
python3/lib/libFreeCADBase.so(_ZN4Base20InterpreterSingleton9runStringB5
cxx11EPKc+0x6a) [0x7f17de156fca]
python3/lib/libFreeCADGui.so(_ZN3Gui7Command11_runCommandEPKciNS0_10DoCm
d_TypeES2_+0x96) [0x7f17df2f8626]
python3/lib/MeshPartGui.so(_ZN11MeshPartGui12Tessellation7processEiPN3Ap
p8DocumentERKNSt7__cxx114listINS1_10SubObjectTESaIS6_EEE+0x2d1)
[0x7f174854a3b1]
python3/lib/MeshPartGui.so(_ZN11MeshPartGui12Tessellation6acceptEv+0x2f4
) [0x7f174854ac64]
python3/lib/libFreeCADGui.so(_ZN3Gui8TaskView8TaskView6acceptEv+0x63)
[0x7f17df6e0873]
[0x7f17dd30e6c8]
gnu/libQt5Widgets.so.5(_ZN15QAbstractButton7clickedEb+0x46)
[0x7f17dd25e8d6]
[0x7f17dd25eb4e]
[0x7f17dd2607af]
gnu/libQt5Widgets.so.5(_ZN15QAbstractButton17mouseReleaseEventEP11QMouse
Event+0x129) [0x7f17dd2609d9]
gnu/libQt5Widgets.so.5(_ZN7QWidget5eventEP6QEvent+0x308)
[0x7f17dd1a72d8]
gnu/libQt5Widgets.so.5(_ZN19QApplicationPrivate13notify_helperEP7QObject
P6QEvent+0x80) [0x7f17dd164240]
gnu/libQt5Widgets.so.5(_ZN12QApplication6notifyEP7QObjectP6QEvent+0x1351
) [0x7f17dd16bba1]
python3/lib/libFreeCADGui.so(_ZN3Gui14GUIApplication6notifyEP7QObjectP6Q
Event+0xc8) [0x7f17df29c6a8]
gnu/libQt5Core.so.5(_ZN16QCoreApplication15notifyInternal2EP7QObjectP6QE
vent+0x128) [0x7f17dc4e94c8]
gnu/libQt5Widgets.so.5(_ZN19QApplicationPrivate14sendMouseEventEP7QWidge
tP11QMouseEventS1_S1_PS1_R8QPointerIS0_Ebb+0x1c4) [0x7f17dd169c24]
[0x7f17dd1c1e2a]
[0x7f17dd1c52ff]

Alright, after pressing the right buttons, I can reproduce it.

The differences with the AppImage are: qt5 vs qt6, coin 4.0.6 vs coin 4.0.3 (this results in the AppImage running on xwayland and the debian package on wayland)

I opened a wishlist bug #1121645 for qt6 build support but I do not know wit this will actually make a difference.

Upstream will not build (AppImage, snap or Flatpak) with coin3 4.0.6 until Ubuntu 26.04 is released.

Michele Cane, PhD

Still happening in  1.1.0+dfsg-1

Mike


On Mon, 01 Dec 2025 18:56:49 +0000 Michele Cane wrote: > On Mon, 20 Oct 2025 17:35:13 +0200 Tobias Frost wrote: > Control: tags -1 -moreinfo > > Alright, after pressing the right buttons, I can reproduce it. > > -- > tobi > > > > Sorry just saw now your replies to this bug. > > The differences with the AppImage are: qt5 vs qt6, coin 4.0.6 vs coin 4.0.3 (this results in the AppImage running on xwayland and the debian package on wayland) > > I opened a wishlist bug #1121645 for qt6 build support but I do not know wit this will actually make a difference. > > Upstream will not build (AppImage, snap or Flatpak) with coin3 4.0.6 until Ubuntu 26.04 is released. > > Michele Cane, PhD

Dear Maintainer,

just tested the latest QT6 build and I am experiencing the same segfault.

Mike

forwarded -1 https://github.com/FreeCAD/FreeCAD/issues/17216

looks like that this is ^^ the issue, the backtrace looks quite
similiar.

Thanks for pointing to the upstream issue. IN the thread they mention the workaround or maybe just the way this should be handled now.

1. you need to install python3-netgen (probaly should be Recommends: )
2. Preferences--> FEM ---> Netgen untick Legacy Netgen see here for more details https://wiki.freecad.org/FEM_MeshNetgenFromShape
3. From the FEM workbench generate Mesh from Shape by Negen
4. FEM Mesh to Mesh

Cheers

Mike

Am Fri, May 08, 2026 at 09:11:20PM +0200 schrieb Michele Cane:

Done, thanks for this!

tobi