Process 667 (gnome-shell) of user 120 dumped core.

Stack trace of thread 667:
#0  0x00007fce741db7eb g_logv (libglib-2.0.so.0)
#1  0x00007fce716943f9 n/a (libcogl.so.20)
#2  0x00007fce71644a6a n/a (libcogl.so.20)
#3  0x00007fce7168a5a5 cogl_framebuffer_allocate (libcogl.so.20)
#4  0x00007fce7164412f n/a (libcogl.so.20)
#5  0x00007fce7168a9a8 cogl_framebuffer_clear4f (libcogl.so.20)
#6  0x00007fce76b84885 st_theme_node_paint (libgnome-shell.so)
#7  0x00007fce76b8ffcf st_widget_paint_background (libgnome-shell.so)
#8  0x00007fce76b8fffc n/a (libgnome-shell.so)
#9  0x00007fce744ab122 n/a (libgobject-2.0.so.0)
#10 0x00007fce744c59d6 g_signal_emit_valist (libgobject-2.0.so.0)
#11 0x00007fce744c60bf g_signal_emit (libgobject-2.0.so.0)
#12 0x00007fce74edd21b clutter_actor_continue_paint (libclutter-1.0.so.0)
#13 0x00007fce74ee33db n/a (libclutter-1.0.so.0)
#14 0x00007fce74ee3710 n/a (libclutter-1.0.so.0)
#15 0x00007fce744ab122 n/a (libgobject-2.0.so.0)
#16 0x00007fce744c59d6 g_signal_emit_valist (libgobject-2.0.so.0)
#17 0x00007fce744c60bf g_signal_emit (libgobject-2.0.so.0)
#18 0x00007fce74edd21b clutter_actor_continue_paint (libclutter-1.0.so.0)
#19 0x00007fce74ee33db n/a (libclutter-1.0.so.0)
#20 0x00007fce74ee3710 n/a (libclutter-1.0.so.0)
#21 0x00007fce744ab122 n/a (libgobject-2.0.so.0)
#22 0x00007fce744c59d6 g_signal_emit_valist (libgobject-2.0.so.0)
#23 0x00007fce744c60bf g_signal_emit (libgobject-2.0.so.0)
#24 0x00007fce74edd21b clutter_actor_continue_paint (libclutter-1.0.so.0)
#25 0x00007fce74ee33db n/a (libclutter-1.0.so.0)
#26 0x00007fce74ee3710 n/a (libclutter-1.0.so.0)
#27 0x00007fce744ab122 n/a (libgobject-2.0.so.0)
#28 0x00007fce744c59d6 g_signal_emit_valist (libgobject-2.0.so.0)
#29 0x00007fce744c60bf g_signal_emit (libgobject-2.0.so.0)
#30 0x00007fce74edd21b clutter_actor_continue_paint (libclutter-1.0.so.0)
#31 0x00007fce74ee33db n/a (libclutter-1.0.so.0)
#32 0x00007fce76b63560 n/a (libgnome-shell.so)
#33 0x00007fce744ab122 n/a (libgobject-2.0.so.0)
#34 0x00007fce744c59d6 g_signal_emit_valist (libgobject-2.0.so.0)
#35 0x00007fce744c60bf g_signal_emit (libgobject-2.0.so.0)
#36 0x00007fce74edd21b clutter_actor_continue_paint (libclutter-1.0.so.0)
#37 0x00007fce74ee33db n/a (libclutter-1.0.so.0)
#38 0x00007fce74f35cca n/a (libclutter-1.0.so.0)
#39 0x00007fce75b1bbb5 n/a (libmutter.so.0)
#40 0x00007fce744ab1d4 n/a (libgobject-2.0.so.0)
#41 0x00007fce744c59d6 g_signal_emit_valist (libgobject-2.0.so.0)
#42 0x00007fce744c60bf g_signal_emit (libgobject-2.0.so.0)
#43 0x00007fce74edd21b clutter_actor_continue_paint (libclutter-1.0.so.0)
#44 0x00007fce74ee33db n/a (libclutter-1.0.so.0)
#45 0x00007fce74f39edb n/a (libclutter-1.0.so.0)
#46 0x00007fce74ecb809 n/a (libclutter-1.0.so.0)
#47 0x00007fce74f38707 n/a (libclutter-1.0.so.0)
#48 0x00007fce74f22459 n/a (libclutter-1.0.so.0)
#49 0x00007fce741d4f07 g_main_context_dispatch (libglib-2.0.so.0)
#50 0x00007fce741d5160 n/a (libglib-2.0.so.0)
#51 0x00007fce741d5482 g_main_loop_run (libglib-2.0.so.0)
#52 0x00007fce75b44d3c meta_run (libmutter.so.0)
#53 0x0000000000402197 main (gnome-shell)
#54 0x00007fce73bed710 __libc_start_main (libc.so.6)
#55 0x00000000004022c9 n/a (gnome-shell)

Stack trace of thread 725:
#0  0x00007fce73f7b03f pthread_cond_wait@@GLIBC_2.3.2 (libpthread.so.0)
#1  0x00007fce66cf34a0 PR_WaitCondVar (libnspr4.so)
#2  0x00007fce6fae3816 n/a (libmozjs-24.so)
#3  0x00007fce66cf8dcb n/a (libnspr4.so)
#4  0x00007fce73f75424 start_thread (libpthread.so.0)
#5  0x00007fce73cb4cbd __clone (libc.so.6)

Stack trace of thread 670:
#0  0x00007fce73cabc3d poll (libc.so.6)
#1  0x00007fce741d50fc n/a (libglib-2.0.so.0)
#2  0x00007fce741d5482 g_main_loop_run (libglib-2.0.so.0)
#3  0x00007fce749de6d6 n/a (libgio-2.0.so.0)
#4  0x00007fce741fb975 n/a (libglib-2.0.so.0)
#5  0x00007fce73f75424 start_thread (libpthread.so.0)
#6  0x00007fce73cb4cbd __clone (libc.so.6)

Stack trace of thread 672:
#0  0x00007fce73cabc3d poll (libc.so.6)
#1  0x00007fce741d50fc n/a (libglib-2.0.so.0)
#2  0x00007fce741d520c g_main_context_iteration (libglib-2.0.so.0)
#3  0x00007fce5996a43d n/a (libdconfsettings.so)
#4  0x00007fce741fb975 n/a (libglib-2.0.so.0)
#5  0x00007fce73f75424 start_thread (libpthread.so.0)
#6  0x00007fce73cb4cbd __clone (libc.so.6)

Stack trace of thread 724:
#0  0x00007fce73f7b03f pthread_cond_wait@@GLIBC_2.3.2 (libpthread.so.0)
#1  0x00007fce66cf34a0 PR_WaitCondVar (libnspr4.so)
#2  0x00007fce6fa6fe9e n/a (libmozjs-24.so)
#3  0x00007fce66cf8dcb n/a (libnspr4.so)
#4  0x00007fce73f75424 start_thread (libpthread.so.0)
#5  0x00007fce73cb4cbd __clone (libc.so.6)

Stack trace of thread 673:
#0  0x00007fce73cabc3d poll (libc.so.6)
#1  0x00007fce7001d1b1 n/a (libpulse.so.0)
#2  0x00007fce7000e761 pa_mainloop_poll (libpulse.so.0)
#3  0x00007fce7000edfe pa_mainloop_iterate (libpulse.so.0)
#4  0x00007fce7000eeb0 pa_mainloop_run (libpulse.so.0)
#5  0x00007fce7001d0f9 n/a (libpulse.so.0)
#6  0x00007fce655c9b08 n/a (libpulsecommon-8.0.so)
#7  0x00007fce73f75424 start_thread (libpthread.so.0)
#8  0x00007fce73cb4cbd __clone (libc.so.6)

Stack trace of thread 669:
#0  0x00007fce73cabc3d poll (libc.so.6)
#1  0x00007fce741d50fc n/a (libglib-2.0.so.0)
#2  0x00007fce741d520c g_main_context_iteration (libglib-2.0.so.0)
#3  0x00007fce741d5249 n/a (libglib-2.0.so.0)
#4  0x00007fce741fb975 n/a (libglib-2.0.so.0)
#5  0x00007fce73f75424 start_thread (libpthread.so.0)
#6  0x00007fce73cb4cbd __clone (libc.so.6)