I have installed KiCad 4.0.7 on another Fedora 28 machine that never had KiCad installed before. Opening any of the demo projects from /usr/share/kicad/demos and starting DRC in pcbnew resulted in crashing with the same assertion failure as in my original message. I also tested 5.0.0-rc2-dev with the KiCad demos and got the same assertion failure. Somehow this seems to be a problem specific to Fedora 28 and not board related. Previously I have been using KiCad 4.0.7 with Fedora 27 and I cannot remember any crashes at all. coredumpctl info ################ Stack trace of thread 8108: #0 0x00007f40849a7f4b raise (libc.so.6) #1 0x00007f4084992591 abort (libc.so.6) #2 0x00007f4042b827c8 n/a (_pcbnew.kiface) #3 0x00007f4042df3271 n/a (_pcbnew.kiface) #4 0x00007f4042df3594 n/a (_pcbnew.kiface) #5 0x00007f4042bcc16f n/a (_pcbnew.kiface) #6 0x00007f40879e5cf2 _ZN12wxEvtHandler23ProcessEventIfMatchesIdERK21wxEventTableEntryBasePS_R7wxEvent (libwx_baseu-3.0.so.0) #7 0x00007f40879e609a _ZN12wxEvtHandler23SearchDynamicEventTableER7wxEvent (libwx_baseu-3.0.so.0) #8 0x00007f40879e6134 _ZN12wxEvtHandler11TryHereOnlyER7wxEvent (libwx_baseu-3.0.so.0) #9 0x00007f40879e61eb _ZN12wxEvtHandler19ProcessEventLocallyER7wxEvent (libwx_baseu-3.0.so.0) #10 0x00007f40879e6281 _ZN12wxEvtHandler12ProcessEventER7wxEvent (libwx_baseu-3.0.so.0) #11 0x00007f40879e601b _ZN12wxEvtHandler18SafelyProcessEventER7wxEvent (libwx_baseu-3.0.so.0) #12 0x00007f40881decd7 wxgtk_button_clicked_callback (libwx_gtk2u_core-3.0.so.0) #13 0x00007f4083ddbadd g_closure_invoke (libgobject-2.0.so.0) #14 0x00007f4083dee9ae signal_emit_unlocked_R (libgobject-2.0.so.0) #15 0x00007f4083df7fda g_signal_emit_valist (libgobject-2.0.so.0) #16 0x00007f4083df85d3 g_signal_emit (libgobject-2.0.so.0) #17 0x00007f4084372645 gtk_real_button_released.part.23 (libgtk-x11-2.0.so.0) #18 0x00007f4083ddbadd g_closure_invoke (libgobject-2.0.so.0) #19 0x00007f4083def056 signal_emit_unlocked_R (libgobject-2.0.so.0) #20 0x00007f4083df7fda g_signal_emit_valist (libgobject-2.0.so.0) #21 0x00007f4083df85d3 g_signal_emit (libgobject-2.0.so.0) #22 0x00007f408437124c gtk_button_button_release (libgtk-x11-2.0.so.0) #23 0x00007f408442c9ad _gtk_marshal_BOOLEAN__BOXED (libgtk-x11-2.0.so.0) #24 0x00007f4083ddbadd g_closure_invoke (libgobject-2.0.so.0) #25 0x00007f4083dee6e4 signal_emit_unlocked_R (libgobject-2.0.so.0) #26 0x00007f4083df7653 g_signal_emit_valist (libgobject-2.0.so.0) #27 0x00007f4083df85d3 g_signal_emit (libgobject-2.0.so.0) #28 0x00007f40845608dc gtk_widget_event_internal (libgtk-x11-2.0.so.0) #29 0x00007f408442a5cc gtk_propagate_event (libgtk-x11-2.0.so.0) #30 0x00007f408442a9cb gtk_main_do_event (libgtk-x11-2.0.so.0) #31 0x00007f408407ff00 gdk_event_dispatch (libgdk-x11-2.0.so.0) #32 0x00007f40833517cd g_main_context_dispatch (libglib-2.0.so.0) #33 0x00007f4083351b98 g_main_context_iterate.isra.21 (libglib-2.0.so.0) #34 0x00007f4083351ec2 g_main_loop_run (libglib-2.0.so.0) #35 0x00007f408442995f gtk_main (libgtk-x11-2.0.so.0) #36 0x00007f408817fbd5 _ZN14wxGUIEventLoop5DoRunEv (libwx_gtk2u_core-3.0.so.0) #37 0x00007f40878b7411 _ZN15wxEventLoopBase3RunEv (libwx_baseu-3.0.so.0) #38 0x00007f408787b0da _ZN16wxAppConsoleBase8MainLoopEv (libwx_baseu-3.0.so.0) #39 0x000055d34c7ae5ad n/a (kicad) #40 0x00007f40879013ab _Z7wxEntryRiPPw (libwx_baseu-3.0.so.0) #41 0x000055d34c795526 n/a (kicad) #42 0x00007f40849941bb __libc_start_main (libc.so.6) #43 0x000055d34c79999a _start (kicad) Stack trace of thread 8224: #0 0x00007f4084a60929 __poll (libc.so.6) #1 0x00007f4083351b06 g_main_context_iterate.isra.21 (libglib-2.0.so.0) #2 0x00007f4083351c30 g_main_context_iteration (libglib-2.0.so.0) #3 0x00007f4083351c81 glib_worker_main (libglib-2.0.so.0) #4 0x00007f4083379cea g_thread_proxy (libglib-2.0.so.0) #5 0x00007f4084d37564 start_thread (libpthread.so.0) #6 0x00007f4084a6b31f __clone (libc.so.6) Stack trace of thread 8256: #0 0x00007f4084a65df9 syscall (libc.so.6) #1 0x00007f408339844e g_cond_wait_until (libglib-2.0.so.0) #2 0x00007f40833240e1 g_async_queue_pop_intern_unlocked (libglib-2.0.so.0) #3 0x00007f40833246d0 g_async_queue_timeout_pop (libglib-2.0.so.0) #4 0x00007f408337a791 g_thread_pool_thread_proxy (libglib-2.0.so.0) #5 0x00007f4083379cea g_thread_proxy (libglib-2.0.so.0) #6 0x00007f4084d37564 start_thread (libpthread.so.0) #7 0x00007f4084a6b31f __clone (libc.so.6) Stack trace of thread 8261: #0 0x00007f408518048e n/a (libgomp.so.1) #1 0x00007f408517dd58 n/a (libgomp.so.1) #2 0x00007f4084d37564 start_thread (libpthread.so.0) #3 0x00007f4084a6b31f __clone (libc.so.6) Stack trace of thread 8259: #0 0x00007f408518048e n/a (libgomp.so.1) #1 0x00007f408517dd58 n/a (libgomp.so.1) #2 0x00007f4084d37564 start_thread (libpthread.so.0) #3 0x00007f4084a6b31f __clone (libc.so.6) Stack trace of thread 8260: #0 0x00007f408518048e n/a (libgomp.so.1) #1 0x00007f408517dd58 n/a (libgomp.so.1) #2 0x00007f4084d37564 start_thread (libpthread.so.0) #3 0x00007f4084a6b31f __clone (libc.so.6) Stack trace of thread 8225: #0 0x00007f4084a60929 __poll (libc.so.6) #1 0x00007f4083351b06 g_main_context_iterate.isra.21 (libglib-2.0.so.0) #2 0x00007f4083351ec2 g_main_loop_run (libglib-2.0.so.0) #3 0x00007f407e47860a gdbus_shared_thread_func (libgio-2.0.so.0) #4 0x00007f4083379cea g_thread_proxy (libglib-2.0.so.0) #5 0x00007f4084d37564 start_thread (libpthread.so.0) #6 0x00007f4084a6b31f __clone (libc.so.6) (gdb) bt ######## #0 0x00007f40849a7f4b in raise () at /lib64/libc.so.6 #1 0x00007f4084992591 in abort () at /lib64/libc.so.6 #2 0x00007f4042b827c8 in () at /usr/bin/_pcbnew.kiface #3 0x00007f4042df3271 in () at /usr/bin/_pcbnew.kiface #4 0x00007f4042df3594 in () at /usr/bin/_pcbnew.kiface #5 0x00007f4042bcc16f in () at /usr/bin/_pcbnew.kiface #6 0x00007f40879e5cf2 in wxEvtHandler::ProcessEventIfMatchesId(wxEventTableEntryBase const&, wxEvtHandler*, wxEvent&) () at /lib64/libwx_baseu-3.0.so.0 #7 0x00007f40879e609a in wxEvtHandler::SearchDynamicEventTable(wxEvent&) () at /lib64/libwx_baseu-3.0.so.0 #8 0x00007f40879e6134 in wxEvtHandler::TryHereOnly(wxEvent&) () at /lib64/libwx_baseu-3.0.so.0 #9 0x00007f40879e61eb in wxEvtHandler::ProcessEventLocally(wxEvent&) () at /lib64/libwx_baseu-3.0.so.0 #10 0x00007f40879e6281 in wxEvtHandler::ProcessEvent(wxEvent&) () at /lib64/libwx_baseu-3.0.so.0 #11 0x00007f40879e601b in wxEvtHandler::SafelyProcessEvent(wxEvent&) () at /lib64/libwx_baseu-3.0.so.0 #12 0x00007f40881decd7 in wxgtk_button_clicked_callback () at /lib64/libwx_gtk2u_core-3.0.so.0 #13 0x00007f4083ddbadd in g_closure_invoke () at /lib64/libgobject-2.0.so.0 #14 0x00007f4083dee9ae in signal_emit_unlocked_R () at /lib64/libgobject-2.0.so.0 #15 0x00007f4083df7fda in g_signal_emit_valist () at /lib64/libgobject-2.0.so.0 #16 0x00007f4083df85d3 in g_signal_emit () at /lib64/libgobject-2.0.so.0 #17 0x00007f4084372645 in gtk_real_button_released.part () at /lib64/libgtk-x11-2.0.so.0 #18 0x00007f4083ddbadd in g_closure_invoke () at /lib64/libgobject-2.0.so.0 #19 0x00007f4083def056 in signal_emit_unlocked_R () at /lib64/libgobject-2.0.so.0 #20 0x00007f4083df7fda in g_signal_emit_valist () at /lib64/libgobject-2.0.so.0 #21 0x00007f4083df85d3 in g_signal_emit () at /lib64/libgobject-2.0.so.0 #22 0x00007f408437124c in gtk_button_button_release () at /lib64/libgtk-x11-2.0.so.0 #23 0x00007f408442c9ad in _gtk_marshal_BOOLEAN__BOXED () at /lib64/libgtk-x11-2.0.so.0 #24 0x00007f4083ddbadd in g_closure_invoke () at /lib64/libgobject-2.0.so.0 #25 0x00007f4083dee6e4 in signal_emit_unlocked_R () at /lib64/libgobject-2.0.so.0 #26 0x00007f4083df7653 in g_signal_emit_valist () at /lib64/libgobject-2.0.so.0 #27 0x00007f4083df85d3 in g_signal_emit () at /lib64/libgobject-2.0.so.0 #28 0x00007f40845608dc in gtk_widget_event_internal () at /lib64/libgtk-x11-2.0.so.0 #29 0x00007f408442a5cc in gtk_propagate_event () at /lib64/libgtk-x11-2.0.so.0 #30 0x00007f408442a9cb in gtk_main_do_event () at /lib64/libgtk-x11-2.0.so.0 #31 0x00007f408407ff00 in gdk_event_dispatch () at /lib64/libgdk-x11-2.0.so.0 #32 0x00007f40833517cd in g_main_context_dispatch () at /lib64/libglib-2.0.so.0 #33 0x00007f4083351b98 in g_main_context_iterate.isra () at /lib64/libglib-2.0.so.0 #34 0x00007f4083351ec2 in g_main_loop_run () at /lib64/libglib-2.0.so.0 #35 0x00007f408442995f in gtk_main () at /lib64/libgtk-x11-2.0.so.0 #36 0x00007f408817fbd5 in wxGUIEventLoop::DoRun() () at /lib64/libwx_gtk2u_core-3.0.so.0 #37 0x00007f40878b7411 in wxEventLoopBase::Run() () at /lib64/libwx_baseu-3.0.so.0 #38 0x00007f408787b0da in wxAppConsoleBase::MainLoop() () at /lib64/libwx_baseu-3.0.so.0 #39 0x000055d34c7ae5ad in () #40 0x00007f40879013ab in wxEntry(int&, wchar_t**) () at /lib64/libwx_baseu-3.0.so.0 #41 0x000055d34c795526 in () #42 0x00007f40849941bb in __libc_start_main () at /lib64/libc.so.6 #43 0x000055d34c79999a in _start ()