Application: systemsettings5 (5.10.4)
 (Compiled from sources)
Qt Version: 5.9.1
Frameworks Version: 5.36.0
Operating System: Linux 4.12.3-gentoo x86_64
Distribution: "Gentoo Base System release 2.4.1"

-- Information about the crash:
- What I was doing when the application crashed:
opening "Display and Monitor" in System Settings utility
opening "Workspace" / "Desktop Effects" in System Settings utility (* backtrace)

Both these sections segfault immediately they are opened.

The crash can be reproduced every time.

-- Backtrace:
Application: System Settings (systemsettings5), signal: Aborted
Using host libthread_db library "/lib64/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f13a8867cc0 (LWP 9061))]

Thread 4 (Thread 0x7f137b46c700 (LWP 9306)):
#0  0x00007f13a398b98d in poll () from /lib64/libc.so.6
#1  0x00007f139c554486 in g_main_context_iterate.isra () from /usr/lib64/libglib-2.0.so.0
#2  0x00007f139c55459c in g_main_context_iteration () from /usr/lib64/libglib-2.0.so.0
#3  0x00007f13a480857b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/libQt5Core.so.5
#4  0x00007f13a47b6a0a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/libQt5Core.so.5
#5  0x00007f13a46120b3 in QThread::exec() () from /usr/lib64/libQt5Core.so.5
#6  0x00007f13a31181f5 in QQmlThreadPrivate::run() () from /usr/lib64/libQt5Qml.so.5
#7  0x00007f13a4616401 in QThreadPrivate::start(void*) () from /usr/lib64/libQt5Core.so.5
#8  0x00007f13a08ff63d in start_thread () from /lib64/libpthread.so.0
#9  0x00007f13a3996d3f in clone () from /lib64/libc.so.6

Thread 3 (Thread 0x7f138e79d700 (LWP 9064)):
#0  0x00007f13a460e779 in QMutex::unlock() () from /usr/lib64/libQt5Core.so.5
#1  0x00007f13a4808491 in postEventSourcePrepare(_GSource*, int*) () from /usr/lib64/libQt5Core.so.5
#2  0x00007f139c553ee9 in g_main_context_check () from /usr/lib64/libglib-2.0.so.0
#3  0x00007f139c554424 in g_main_context_iterate.isra () from /usr/lib64/libglib-2.0.so.0
#4  0x00007f139c55459c in g_main_context_iteration () from /usr/lib64/libglib-2.0.so.0
#5  0x00007f13a480857b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/libQt5Core.so.5
#6  0x00007f13a47b6a0a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/libQt5Core.so.5
#7  0x00007f13a46120b3 in QThread::exec() () from /usr/lib64/libQt5Core.so.5
#8  0x00007f13a896eac5 in QDBusConnectionManager::run() () from /usr/lib64/libQt5DBus.so.5
#9  0x00007f13a4616401 in QThreadPrivate::start(void*) () from /usr/lib64/libQt5Core.so.5
#10 0x00007f13a08ff63d in start_thread () from /lib64/libpthread.so.0
#11 0x00007f13a3996d3f in clone () from /lib64/libc.so.6

Thread 2 (Thread 0x7f13971b5700 (LWP 9063)):
#0  0x00007f13a398b98d in poll () from /lib64/libc.so.6
#1  0x00007f13a0f4185f in _xcb_conn_wait () from /usr/lib64/libxcb.so.1
#2  0x00007f13a0f435e9 in xcb_wait_for_event () from /usr/lib64/libxcb.so.1
#3  0x00007f1399728029 in QXcbEventReader::run() () from /usr/lib64/libQt5XcbQpa.so.5
#4  0x00007f13a4616401 in QThreadPrivate::start(void*) () from /usr/lib64/libQt5Core.so.5
#5  0x00007f13a08ff63d in start_thread () from /lib64/libpthread.so.0
#6  0x00007f13a3996d3f in clone () from /lib64/libc.so.6

Thread 1 (Thread 0x7f13a8867cc0 (LWP 9061)):
[KCrash Handler]
#6  0x00007f13a38d2f10 in raise () from /lib64/libc.so.6
#7  0x00007f13a38d4bba in abort () from /lib64/libc.so.6
#8  0x00007f13a4602da9 in QMessageLogger::fatal(char const*, ...) const () from /usr/lib64/libQt5Core.so.5
#9  0x00007f13a33c8328 in QSGRenderLoop::handleContextCreationFailure(QQuickWindow*, bool) () from /usr/lib64/libQt5Quick.so.5
#10 0x00007f13a33c9595 in QSGGuiThreadRenderLoop::renderWindow(QQuickWindow*) () from /usr/lib64/libQt5Quick.so.5
#11 0x00007f13a33c9df5 in QSGGuiThreadRenderLoop::exposureChanged(QQuickWindow*) () from /usr/lib64/libQt5Quick.so.5
#12 0x00007f13a5710dd5 in QWindow::event(QEvent*) () from /usr/lib64/libQt5Gui.so.5
#13 0x00007f13a343e445 in QQuickWindow::event(QEvent*) () from /usr/lib64/libQt5Quick.so.5
#14 0x00007f13a5c1507c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib64/libQt5Widgets.so.5
#15 0x00007f13a5c1c989 in QApplication::notify(QObject*, QEvent*) () from /usr/lib64/libQt5Widgets.so.5
#16 0x00007f13a47b7cda in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /usr/lib64/libQt5Core.so.5
#17 0x00007f13a570633d in QGuiApplicationPrivate::processExposeEvent(QWindowSystemInterfacePrivate::ExposeEvent*) () from /usr/lib64/libQt5Gui.so.5
#18 0x00007f13a5706fcd in QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*) () from /usr/lib64/libQt5Gui.so.5
#19 0x00007f13a56e3f1b in QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/libQt5Gui.so.5
#20 0x00007f13997879a0 in userEventSourceDispatch(_GSource*, int (*)(void*), void*) () from /usr/lib64/libQt5XcbQpa.so.5
#21 0x00007f139c554172 in g_main_context_dispatch () from /usr/lib64/libglib-2.0.so.0
#22 0x00007f139c5544f0 in g_main_context_iterate.isra () from /usr/lib64/libglib-2.0.so.0
#23 0x00007f139c55459c in g_main_context_iteration () from /usr/lib64/libglib-2.0.so.0
#24 0x00007f13a480855f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/libQt5Core.so.5
#25 0x00007f13a47b6a0a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/libQt5Core.so.5
#26 0x00007f13a47bef34 in QCoreApplication::exec() () from /usr/lib64/libQt5Core.so.5
#27 0x000000000040b684 in main ()

Reported using DrKonqi