While trying to reproduce bug 727438, I produced this:


==23613== Invalid read of size 8
==23613==    at 0x4FAB2DA: cb_resize_vpane_finish (sheet-control-gui.c:1413)
==23613==    by 0x6402702: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4000.0)
==23613==    by 0x6401CE4: g_main_context_dispatch (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4000.0)
==23613==    by 0x6402047: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4000.0)
==23613==    by 0x6402309: g_main_loop_run (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4000.0)
==23613==    by 0x5950E44: gtk_main (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.1000.8)
==23613==    by 0x404C34: main (main-application.c:392)
==23613==  Address 0x11fd06a0 is 144 bytes inside a block of size 336 free'd
==23613==    at 0x4C2BDEC: free (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==23613==    by 0x619907B: g_type_free_instance (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.4000.0)
==23613==    by 0x61783D5: g_closure_invoke (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.4000.0)
==23613==    by 0x6189D3C: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.4000.0)
==23613==    by 0x6191A28: g_signal_emit_valist (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.4000.0)
==23613==    by 0x6191CE1: g_signal_emit (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.4000.0)
==23613==    by 0x5A85E17: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.1000.8)
==23613==    by 0x617EACF: g_object_run_dispose (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.4000.0)
==23613==    by 0x5008BC3: wbcg_sheet_remove_all (wbc-gtk.c:1338)
==23613==    by 0x50039A0: wb_control_sheet_remove_all (workbook-control.c:96)
==23613==    by 0x4FFB2F0: workbook_dispose (workbook.c:128)