Application: systemsettings5 (5.4.1)
 (Compiled from sources)
Qt Version: 5.4.2
Operating System: Linux 4.2.0 x86_64
Distribution: "Gentoo Base System release 2.2"

-- Information about the crash:
- What I was doing when the application crashed:
I was reconfiguring some parameters of user interface like keyboard mappings and windows appearance. After exiting from kdesystemsetting, a crash occurred

-- Backtrace:
Application: Impostazioni di sistema (systemsettings5), signal: Segmentation fault
Using host libthread_db library "/lib64/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f6d94c35800 (LWP 15420))]

Thread 2 (Thread 0x7f6d90c2f700 (LWP 15422)):
#0  0x00007f6d9e8bb3ad in poll () from /lib64/libc.so.6
#1  0x00007f6d9c841ac2 in poll (__timeout=-1, __nfds=1, __fds=0x7f6d90c2ecc0) at /usr/include/bits/poll2.h:46
#2  _xcb_conn_wait (c=c@entry=0x2321120, cond=cond@entry=0x2321160, vector=vector@entry=0x0, count=count@entry=0x0) at /var/tmp/portage/x11-libs/libxcb-1.11.1/work/libxcb-1.11.1/src/xcb_conn.c:459
#3  0x00007f6d9c84372f in xcb_wait_for_event (c=0x2321120) at /var/tmp/portage/x11-libs/libxcb-1.11.1/work/libxcb-1.11.1/src/xcb_in.c:693
#4  0x00007f6d949a44f9 in QXcbEventReader::run (this=0x2456440) at qxcbconnection.cpp:1105
#5  0x00007f6d9ef23aa2 in QThreadPrivate::start(void*) () from /usr/lib64/libQt5Core.so.5
#6  0x00007f6d9bfcc324 in start_thread () from /lib64/libpthread.so.0
#7  0x00007f6d9e8c41ad in clone () from /lib64/libc.so.6

Thread 1 (Thread 0x7f6d94c35800 (LWP 15420)):
[KCrash Handler]
#6  QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::data (this=0x39) at /usr/include/qt5/QtCore/qscopedpointer.h:135
#7  qGetPtrHelper<QScopedPointer<QObjectData> > (p=...) at /usr/include/qt5/QtCore/qglobal.h:962
#8  QQuickWindow::d_func (this=0x31) at items/qquickwindow.h:66
#9  QQuickWindow::maybeUpdate (this=0x31) at items/qquickwindow.cpp:2892
#10 0x00007f6d9dc19b59 in QQuickWindowPrivate::dirtyItem (this=<optimized out>) at items/qquickwindow.cpp:930
#11 0x00007f6d9dc05f6d in QQuickItemPrivate::addToDirtyList (this=<optimized out>) at items/qquickitem.cpp:5634
#12 0x00007f6d9dc05fe8 in QQuickItemPrivate::dirty (this=0x2cbab50, type=<optimized out>) at items/qquickitem.cpp:5615
#13 0x00007f6d9dc067fe in QQuickItem::update (this=<optimized out>) at items/qquickitem.cpp:4094
#14 0x00007f6d9dc0ff35 in QQuickItem::qt_static_metacall (_o=<optimized out>, _c=<optimized out>, _id=<optimized out>, _a=<optimized out>) at .moc/moc_qquickitem.cpp:595
#15 0x00007f6d9f0f89fa in QObject::event(QEvent*) () from /usr/lib64/libQt5Core.so.5
#16 0x00007f6d9dc0eacb in QQuickItem::event (this=0x2cbaad0, ev=0x7f6d78501450) at items/qquickitem.cpp:7302
#17 0x00007f6da044863c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib64/libQt5Widgets.so.5
#18 0x00007f6da044da20 in QApplication::notify(QObject*, QEvent*) () from /usr/lib64/libQt5Widgets.so.5
#19 0x00007f6d9f0ce24d in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib64/libQt5Core.so.5
#20 0x00007f6d9f0d0cd3 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /usr/lib64/libQt5Core.so.5
#21 0x00007f6d9f11c553 in postEventSourceDispatch(_GSource*, int (*)(void*), void*) () from /usr/lib64/libQt5Core.so.5
#22 0x00007f6d9a3688ed in g_main_dispatch (context=0x7f6d8c002450) at /var/tmp/portage/dev-libs/glib-2.44.1/work/glib-2.44.1/glib/gmain.c:3122
#23 g_main_context_dispatch (context=context@entry=0x7f6d8c002450) at /var/tmp/portage/dev-libs/glib-2.44.1/work/glib-2.44.1/glib/gmain.c:3737
#24 0x00007f6d9a368bd0 in g_main_context_iterate (context=context@entry=0x7f6d8c002450, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.44.1/work/glib-2.44.1/glib/gmain.c:3808
#25 0x00007f6d9a368c7c in g_main_context_iteration (context=0x7f6d8c002450, may_block=1) at /var/tmp/portage/dev-libs/glib-2.44.1/work/glib-2.44.1/glib/gmain.c:3869
#26 0x00007f6d9f11c5c7 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/libQt5Core.so.5
#27 0x00007f6d9f0ccf2a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib64/libQt5Core.so.5
#28 0x00007f6d9f0d3cdc in QCoreApplication::exec() () from /usr/lib64/libQt5Core.so.5
#29 0x000000000040f6bb in main (argc=1, argv=<optimized out>) at /var/tmp/portage/kde-plasma/systemsettings-5.4.1/work/systemsettings-5.4.1/app/main.cpp:55

Reported using DrKonqi