#0  0x00007f50c635e418 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
        resultvar = 0
        pid = 4645
        selftid = 4645
#1  0x00007f50c636001a in __GI_abort () at abort.c:89
        save_stage = 2
        act = {__sigaction_handler = {sa_handler = 0x0, sa_sigaction = 0x0}, sa_mask = {__val = {0, 0, 139984899808047, 139984903263552, 1, 0, 139984900323885, 10, 139984909143912, 139984914102112, 139984914102112, 1, 139984914104464, 94251723446224, 66, 139984914102144}}, sa_flags = -963021792, sa_restorer = 0x55b8b08db878}
        sigs = {__val = {32, 0 <repeats 15 times>}}
#2  0x00007f50c699a4ad in __gnu_cxx::__verbose_terminate_handler() () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
No symbol table info available.
#3  0x00007f50c6998256 in ?? () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
No symbol table info available.
#4  0x00007f50c69982a1 in std::terminate() () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
No symbol table info available.
#5  0x00007f50c69984b9 in __cxa_throw () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
No symbol table info available.
#6  0x00007f50a54982cc in void boost::throw_exception<boost::bad_function_call>(boost::bad_function_call const&) () from /usr/lib/x86_64-linux-gnu/compiz/libunityshell.so
No symbol table info available.
#7  0x00007f50a55d89e4 in unity::lockscreen::AcceleratorController::OnActionActivated(CompAction&) () from /usr/lib/x86_64-linux-gnu/compiz/libunityshell.so
No symbol table info available.
#8  0x00007f50a55d9902 in unity::lockscreen::Accelerator::KeyReleaseActivate() () from /usr/lib/x86_64-linux-gnu/compiz/libunityshell.so
No symbol table info available.
#9  0x00007f50a55d9df8 in unity::lockscreen::Accelerator::HandleKeyRelease(unsigned int, unsigned int, unity::lockscreen::PressedState) () from /usr/lib/x86_64-linux-gnu/compiz/libunityshell.so
No symbol table info available.
#10 0x00007f50a55da766 in unity::lockscreen::Accelerators::HandleKeyRelease(unsigned int, unsigned int) () from /usr/lib/x86_64-linux-gnu/compiz/libunityshell.so
No symbol table info available.
#11 0x00007f50a55eaa1d in unity::lockscreen::Shield::FindKeyFocusArea(unsigned int, unsigned long, unsigned long) () from /usr/lib/x86_64-linux-gnu/compiz/libunityshell.so
No symbol table info available.
#12 0x00007f50a4149f8e in nux::WindowCompositor::FindKeyFocusAreaFrom(nux::EventType, unsigned int, unsigned int, nux::InputArea*, nux::ObjectWeakPtr<nux::InputArea>&, nux::ObjectWeakPtr<nux::BaseWindow>&) () from /usr/lib/x86_64-linux-gnu/libnux-4.0.so.0
No symbol table info available.
#13 0x00007f50a41530ad in nux::WindowCompositor::KeyboardEventCycle(nux::Event&) () from /usr/lib/x86_64-linux-gnu/libnux-4.0.so.0
No symbol table info available.
#14 0x00007f50a415363d in nux::WindowCompositor::ProcessEvent(nux::Event&) () from /usr/lib/x86_64-linux-gnu/libnux-4.0.so.0
No symbol table info available.
#15 0x00007f50a4157f09 in nux::WindowThread::DoProcessEvent(nux::Event&) () from /usr/lib/x86_64-linux-gnu/libnux-4.0.so.0
No symbol table info available.
#16 0x00007f50a41298a6 in nux::nux_event_dispatch(_GSource*, int (*)(void*), void*) () from /usr/lib/x86_64-linux-gnu/libnux-4.0.so.0
No symbol table info available.
#17 0x00007f50c4c520da in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
No symbol table info available.
#18 0x00007f50c4c52480 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
No symbol table info available.
#19 0x00007f50c4c527a2 in g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
No symbol table info available.
#20 0x00007f50c6ce2c1f in compiz::private_screen::EventManager::startEventLoop(_XDisplay*) () from /usr/lib/x86_64-linux-gnu/libcompiz_core.so.ABI-20151010
No symbol table info available.
#21 0x000055b8ac47f7b1 in main ()
No symbol table info available.