Sometimes after I dragged some tracks/vias in routing mode and press ESC a "Clarify Selection" dialog pops up. It *think* it always contains two entries. When I move the mouse pointer over an entry a "ghost track/via" appears. These are tracks/vias before the drag operation.
When I click on an entry in order to select the highlighted track/via and remove the elements by pressing "DEL", pcbnew crashes.

Maybe six month ago this clarify dialog appeared quite often and removing selected "ghost elements" did not lead to a crash but all routed tracks disappeared. Not immediately but the displayed tracks could no longer be edited and after reopening the board file the tracks were gone if the file has been saved after the remove operation. This bug has been (partly?) fixed.

Now I could reproduce this behavior while pcbnew was running within a gdb session. The crash is apparently a set of failed assertions. Pcbnew did not crash within gdb (at least not until I closed it) and after I saved the current board and reopened it all tracks/vias were gone.

Maybe this is the same bug as described here and Linux/Windows behave differently.

Console output:

/data/src/kicad-source-mirror/common/view/view.cpp(374): assert "viewData->m_view == this" failed in Remove().
[Thread 0x7fffcedd1700 (LWP 24032) exited]
/data/src/kicad-source-mirror/common/dlist.cpp(163): assert "aElement->GetList() == this" failed in remove().
/data/src/kicad-source-mirror/common/dlist.cpp(171): assert "last == aElement" failed in remove().
/data/src/kicad-source-mirror/common/dlist.cpp(181): assert "first == aElement" failed in remove().
[New Thread 0x7fffcedd1700 (LWP 24117)]



GDB output after I closed pcbnew:

Thread 1 "kicad" received signal SIGSEGV, Segmentation fault.
0x00000000000000a1 in ?? ()
(gdb) bt
#0  0x00000000000000a1 in ?? ()
#1  0x00007fffe58a7e17 in PICKED_ITEMS_LIST::ClearListAndDeleteItems (this=0x3bbe6b0) at /data/src/kicad-source-mirror/common/undo_redo_container.cpp:135
#2  0x00007fffe51eedff in PCB_SCREEN::ClearUndoORRedoList (this=0x402b160, aList=..., aItemCount=-1) at /data/src/kicad-source-mirror/pcbnew/undo_redo.cpp:614
#3  0x00007fffe561086b in BASE_SCREEN::ClearUndoRedoList (this=0x402b160) at /data/src/kicad-source-mirror/common/base_screen.cpp:409
#4  0x00007fffe5138315 in PCB_EDIT_FRAME::Clear_Pcb (this=0x27bf4c0, aQuery=false) at /data/src/kicad-source-mirror/pcbnew/initpcb.cpp:52
#5  0x00007fffe51803a0 in PCB_EDIT_FRAME::OnCloseWindow (this=0x27bf4c0, Event=...) at /data/src/kicad-source-mirror/pcbnew/pcb_edit_frame.cpp:719
#6  0x00007ffff648736e in wxAppConsoleBase::CallEventHandler (this=0x822890, handler=0x27bf4c0, functor=..., event=...) at ../src/common/appbase.cpp:623
#7  0x00007ffff660d4d7 in wxEvtHandler::ProcessEventIfMatchesId (entry=..., handler=<optimized out>, event=...) at ../src/common/event.cpp:1390
#8  0x00007ffff660d5cb in wxEventHashTable::HandleEvent (this=<optimized out>, event=..., self=self@entry=0x27bf4c0) at ../src/common/event.cpp:996
#9  0x00007ffff660d97b in wxEvtHandler::TryHereOnly (this=0x27bf4c0, event=...) at ../src/common/event.cpp:1587
#10 0x00007fffe586be9c in EDA_BASE_FRAME::ProcessEvent (this=0x27bf4c0, aEvent=...) at /data/src/kicad-source-mirror/common/eda_base_frame.cpp:194
#11 0x00007ffff660d783 in wxEvtHandler::DoTryChain (this=<optimized out>, event=...) at ../src/common/event.cpp:1552
#12 0x00007ffff660da65 in wxEvtHandler::ProcessEvent (this=0x27bf928, event=...) at ../src/common/event.cpp:1493
#13 0x00007ffff660d7d7 in wxEvtHandler::SafelyProcessEvent (this=<optimized out>, event=...) at ../src/common/event.cpp:1611
#14 0x00007ffff6fb10ec in wxWindowBase::HandleWindowEvent (this=this@entry=0x27bf4c0, event=...) at ../src/common/wincmn.cpp:1525
#15 0x00007ffff6fb13f7 in wxWindowBase::Close (this=this@entry=0x27bf4c0, force=force@entry=false) at ../src/common/wincmn.cpp:589
#16 0x00007ffff6db9464 in gtk_frame_delete_callback (win=0x27bf4c0) at ../src/gtk/toplevel.cpp:303
#17 0x00007ffff49c7aec in ?? () from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#18 0x00007ffff439cfa5 in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#19 0x00007ffff43aefc1 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#20 0x00007ffff43b77f9 in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#21 0x00007ffff43b808f in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#22 0x00007ffff4adf93c in ?? () from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#23 0x00007ffff49c684d in gtk_main_do_event () from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#24 0x00007ffff463ac8c in ?? () from /usr/lib/x86_64-linux-gnu/libgdk-x11-2.0.so.0
#25 0x00007ffff3c58197 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#26 0x00007ffff3c583f0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
---Type <return> to continue, or q <return> to quit--- 
#27 0x00007ffff3c58712 in g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#28 0x00007ffff49c5697 in gtk_main () from /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0
#29 0x00007ffff6d98be5 in wxGUIEventLoop::DoRun (this=0xab6810) at ../src/gtk/evtloop.cpp:65
#30 0x00007ffff64c8d23 in wxEventLoopBase::Run (this=0xab6810) at ../src/common/evtloopcmn.cpp:78
#31 0x00007ffff648df56 in wxAppConsoleBase::MainLoop (this=0x822890) at ../src/common/appbase.cpp:334
#32 0x000000000047811d in APP_KICAD::OnRun (this=0x822890) at /data/src/kicad-source-mirror/kicad/kicad.cpp:233
#33 0x00007ffff651a9a0 in wxEntry (argc=<optimized out>, argv=<optimized out>) at ../src/common/init.cpp:506
#34 0x0000000000476b9b in main (argc=1, argv=0x7fffffffdcf8) at /data/src/kicad-source-mirror/kicad/kicad.cpp:265