(gdb) run
Starting program: /opt/inkscape0.92pre/bin/inkscape 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7fffe5b18700 (LWP 8949)]
[New Thread 0x7fffe5317700 (LWP 8950)]
[New Thread 0x7fffe4b16700 (LWP 8951)]
[New Thread 0x7fffe2a53700 (LWP 8952)]
[New Thread 0x7fffe2252700 (LWP 8953)]

Thread 1 "inkscape" received signal SIGSEGV, Segmentation fault.
0x0000000000d18466 in Inkscape::UI::Tools::PenTool::_bsplineSpiroOn() ()
(gdb) bt
#0  0x0000000000d18466 in Inkscape::UI::Tools::PenTool::_bsplineSpiroOn() ()
#1  0x0000000000d195e0 in Inkscape::UI::Tools::PenTool::_bsplineSpiro(bool) ()
#2  0x0000000000d1a72d in Inkscape::UI::Tools::PenTool::_finishSegment(Geom::Point, unsigned int) ()
#3  0x0000000000d1b683 in Inkscape::UI::Tools::PenTool::_handleKeyPress(_GdkEvent*) ()
#4  0x0000000000d1d94d in Inkscape::UI::Tools::PenTool::root_handler(_GdkEvent*) ()
#5  0x0000000000d384ea in Inkscape::UI::Tools::sp_event_context_virtual_root_handler(Inkscape::UI::Tools::ToolBase*, _GdkEvent*) ()
#6  0x00000000006e7ffc in sp_desktop_root_handler(SPCanvasItem*, _GdkEvent*, SPDesktop*) ()
#7  0x00000000009743fc in sp_marshal_BOOLEAN__POINTER ()
#8  0x00007ffff10a0fa5 in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#9  0x00007ffff10b2fc1 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#10 0x00007ffff10bb7f9 in g_signal_emit_valist ()
   from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#11 0x00007ffff10bc08f in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#12 0x00000000008a15e9 in SPCanvas::emitEvent(_GdkEvent*) ()
#13 0x00007ffff4fd3afc in ?? () from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#14 0x00007ffff10a0eff in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#15 0x00007ffff10b356e in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#16 0x00007ffff10bb7f9 in g_signal_emit_valist ()
   from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#17 0x00007ffff10bc08f in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#18 0x00007ffff50eb8cc in ?? () from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#19 0x00007ffff50ff39d in gtk_window_propagate_key_event ()
   from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#20 0x00007ffff5101e1b in ?? () from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#21 0x00007ffff4fd3afc in ?? () from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#22 0x00007ffff10a0fa5 in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#23 0x00007ffff10b356e in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#24 0x00007ffff10bb7f9 in g_signal_emit_valist ()
   from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#25 0x00007ffff10bc08f in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#26 0x00007ffff50eb8cc in ?? () from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#27 0x00007ffff4fd2377 in gtk_propagate_event ()
   from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#28 0x00007ffff4fd264b in gtk_main_do_event ()
   from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#29 0x00007ffff4c46c4c in ?? () from /usr/lib/x86_64-linux-gnu/libgdk-x11-2.0.so.0
#30 0x00007ffff0dca1a7 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#31 0x00007ffff0dca400 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#32 0x00007ffff0dca722 in g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#33 0x00007ffff4fd16a7 in gtk_main () from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#34 0x00000000006c3631 in sp_main_gui(int, char const**) ()
#35 0x00007fffefc06830 in __libc_start_main () from /lib/x86_64-linux-gnu/libc.so.6
---Type <return> to continue, or q <return> to quit---
#36 0x00000000006bfb09 in _start ()
(gdb)