(0.64.x) Change bones parent to "No Parent" , Segfault.

After add a second bones (convert a new spline point to bones influence) i have changed parent to BonesX , and then parent to “No Parent”

I don’t find a direct way to reproduce, but ‘playing’ with parent and then ‘no parent’ for a while, the segfault should appear (even with the ‘first’ bone created).

Thread 1 (Thread 0xb5f79880 (LWP 22723)): #0 0xb7b558d7 in synfig::Bone::is_root (this=0xbfff3668) at bone.cpp:146 #1 0x086474ec in studio::Duckmatic::add_to_ducks (this=0x96e598c, value_desc=..., canvas_view=..., transform_stack=..., param_desc=0x0, multiple=0) at duckmatic.cpp:2933 #2 0x08649890 in studio::Duckmatic::add_to_ducks (this=0x96e598c, value_desc=..., canvas_view=..., transform_stack=..., param_desc=0x0, multiple=0) at duckmatic.cpp:3129 #3 0x08644fdb in studio::Duckmatic::add_to_ducks (this=0x96e598c, value_desc=..., canvas_view=..., transform_stack=..., param_desc=0x0, multiple=0) at duckmatic.cpp:2674 #4 0x086404da in studio::Duckmatic::add_to_ducks (this=0x96e598c, value_desc=..., canvas_view=..., transform_stack=..., param_desc=0x9f2f8a0, multiple=0) at duckmatic.cpp:2164 #5 0x0863b304 in studio::Duckmatic::add_ducks_layers (this=0x96e598c, canvas=..., selected_layer_set=..., canvas_view=..., transform_stack=...) at duckmatic.cpp:1588 #6 0x0863bb50 in studio::Duckmatic::add_ducks_layers (this=0x96e598c, canvas=..., selected_layer_set=..., canvas_view=..., transform_stack=...) at duckmatic.cpp:1623 #7 0x0863bb50 in studio::Duckmatic::add_ducks_layers (this=0x96e598c, canvas=..., selected_layer_set=..., canvas_view=..., transform_stack=...) at duckmatic.cpp:1623 #8 0x0863bb50 in studio::Duckmatic::add_ducks_layers (this=0x96e598c, canvas=..., selected_layer_set=..., canvas_view=..., transform_stack=...) at duckmatic.cpp:1623 #9 0x0860dacc in studio::CanvasView::rebuild_ducks (this=0x940e710) at canvasview.cpp:3048 #10 0x0862b13e in sigc::bound_mem_functor0<void, studio::CanvasView>::operator() (this=0x9ea21c8) at /usr/include/sigc++-2.0/sigc++/functors/mem_fun.h:1787 #11 0x08628846 in sigc::adaptor_functor<sigc::bound_mem_functor0<void, studio::CanvasView> >::operator() (this=0x9ea21c4) at /usr/include/sigc++-2.0/sigc++/adaptors/adaptor_trait.h:251 #12 0x0862a774 in sigc::bind_return_functor<bool, sigc::bound_mem_functor0<void, studio::CanvasView> >::operator() (this=0x9ea21c0) at /usr/include/sigc++-2.0/sigc++/adaptors/bind_return.h:173 #13 0x086276c3 in sigc::internal::slot_call0<sigc::bind_return_functor<bool, sigc::bound_mem_functor0<void, studio::CanvasView> >, bool>::call_it (rep=0x9ea21a8) at /usr/include/sigc++-2.0/sigc++/functors/slot.h:103 #14 0xb6ce90e4 in ?? () from /usr/lib/i386-linux-gnu/libglibmm-2.4.so.1 #15 0xb66bd1d7 in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0 #16 0xb66bc483 in g_main_context_dispatch () from /lib/i386-linux-gnu/libglib-2.0.so.0 #17 0xb66bc820 in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0 #18 0xb66bccfb in g_main_loop_run () from /lib/i386-linux-gnu/libglib-2.0.so.0 #19 0xb6e4ead0 in gtk_main () from /usr/lib/i386-linux-gnu/libgtk-x11-2.0.so.0 #20 0xb755d264 in Gtk::Main::run_impl() () from /usr/lib/libgtkmm-2.4.so.1 #21 0xb755dc9f in Gtk::Main::run() () from /usr/lib/libgtkmm-2.4.so.1 #22 0x083c2a72 in main (argc=0, argv=0xbffffb24) at main.cpp:108