Created attachment 105005 [details]
Keyboard layout that can't be previewed

Application: systemsettings (4.11.11)
KDE Platform Version: 4.13.3
Qt Version: 4.8.6
Operating System: Linux 4.2.0-42-generic x86_64
Distribution: Ubuntu 14.04 LTS

-- Information about the crash:
- What I was doing when the application crashed:
In Hardware > Input devices > Keyboard, tab Layouts.
Select my current layout and click Preview.
100% crash.


- Custom settings of the application:
The keyboard layout I'm using is a custom one that I've written myself. Previous versions of KDE did not use to crash and displayed it correctly, but I can't remember at what version it started crashing.
I'll be attaching the .xkb file to the bug report.

The crash can be reproduced every time.

-- Backtrace:
Application: System Settings (systemsettings), signal: Segmentation fault
Using host libthread_db library "/usr/grte/v4/lib64/libthread_db.so.1".
[Current thread is 1 (Thread 0x7fd0fdeac7c0 (LWP 13616))]

Thread 2 (Thread 0x7fd0de184700 (LWP 13617)):
#0  0x00007fd0f3e3a61a in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x00007fd0f3e3a9a9 in g_mutex_unlock () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fd0f3df8ef6 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fd0f3df90ec in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fd0fb6307be in QEventDispatcherGlib::processEvents (this=0x7fd0d80008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:436
#5  0x00007fd0fb6020af in QEventLoop::processEvents (this=this@entry=0x7fd0de183de0, flags=...) at kernel/qeventloop.cpp:149
#6  0x00007fd0fb6023a5 in QEventLoop::exec (this=this@entry=0x7fd0de183de0, flags=...) at kernel/qeventloop.cpp:204
#7  0x00007fd0fb4fec5f in QThread::exec (this=this@entry=0x2585b40) at thread/qthread.cpp:537
#8  0x00007fd0fb5e3823 in QInotifyFileSystemWatcherEngine::run (this=0x2585b40) at io/qfilesystemwatcher_inotify.cpp:265
#9  0x00007fd0fb50132f in QThreadPrivate::start (arg=0x2585b40) at thread/qthread_unix.cpp:349
#10 0x00007fd0f42d8184 in start_thread (arg=0x7fd0de184700) at pthread_create.c:312
#11 0x00007fd0faeb7bed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 1 (Thread 0x7fd0fdeac7c0 (LWP 13616)):
[KCrash Handler]
#6  ref (this=0x440041003d0045) at /usr/include/qt4/QtCore/qatomic_x86_64.h:121
#7  QString (other=..., this=0x7fff1c883d70) at /usr/include/qt4/QtCore/qstring.h:726
#8  KbPreviewFrame::generateKeyboardLayout (this=0x5082990, layout=..., layoutVariant=...) at ../../../kcontrol/keyboard/preview/kbpreviewframe.cpp:345
#9  0x00007fd0dc322b99 in KeyboardPainter::generateKeyboardLayout (this=this@entry=0x5013260, layout=..., variant=...) at ../../../kcontrol/keyboard/preview/keyboardpainter.cpp:46
#10 0x00007fd0dc2fbbba in KCMKeyboardWidget::previewLayout (this=<optimized out>) at ../../../kcontrol/keyboard/kcm_keyboard_widget.cpp:386
#11 0x00007fd0dc2f6a15 in KCMKeyboardWidget::qt_static_metacall (_o=<optimized out>, _id=<optimized out>, _a=<optimized out>, _c=<optimized out>) at moc_kcm_keyboard_widget.cpp:87
#12 0x00007fd0fb61787a in QMetaObject::activate (sender=sender@entry=0x4e74690, m=m@entry=0x7fd0fcd432a0 <QAbstractButton::staticMetaObject>, local_signal_index=local_signal_index@entry=2, argv=argv@entry=0x7fff1c884050) at kernel/qobject.cpp:3539
#13 0x00007fd0fc8be172 in QAbstractButton::clicked (this=this@entry=0x4e74690, _t1=false) at .moc/release-shared/moc_qabstractbutton.cpp:219
#14 0x00007fd0fc621a63 in QAbstractButtonPrivate::emitClicked (this=this@entry=0x4e74830) at widgets/qabstractbutton.cpp:548
#15 0x00007fd0fc622bd3 in QAbstractButtonPrivate::click (this=this@entry=0x4e74830) at widgets/qabstractbutton.cpp:541
#16 0x00007fd0fc622cbc in QAbstractButton::mouseReleaseEvent (this=0x4e74690, e=0x7fff1c884540) at widgets/qabstractbutton.cpp:1123
#17 0x00007fd0fc2bf51a in QWidget::event (this=0x4e74690, event=0x7fff1c884540) at kernel/qwidget.cpp:8376
#18 0x00007fd0fc26fe2c in QApplicationPrivate::notify_helper (this=this@entry=0x203f180, receiver=receiver@entry=0x4e74690, e=e@entry=0x7fff1c884540) at kernel/qapplication.cpp:4567
#19 0x00007fd0fc2765dd in QApplication::notify (this=this@entry=0x7fff1c884d90, receiver=receiver@entry=0x4e74690, e=e@entry=0x7fff1c884540) at kernel/qapplication.cpp:4110
#20 0x00007fd0fcf7a63a in KApplication::notify (this=0x7fff1c884d90, receiver=0x4e74690, event=0x7fff1c884540) at ../../kdeui/kernel/kapplication.cpp:311
#21 0x00007fd0fb6034dd in QCoreApplication::notifyInternal (this=0x7fff1c884d90, receiver=receiver@entry=0x4e74690, event=event@entry=0x7fff1c884540) at kernel/qcoreapplication.cpp:953
#22 0x00007fd0fc275d93 in sendEvent (event=<optimized out>, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#23 QApplicationPrivate::sendMouseEvent (receiver=receiver@entry=0x4e74690, event=event@entry=0x7fff1c884540, alienWidget=alienWidget@entry=0x4e74690, nativeWidget=nativeWidget@entry=0x22b7ea0, buttonDown=buttonDown@entry=0x7fd0fcd55318 <qt_button_down>, lastMouseReceiver=..., spontaneous=spontaneous@entry=true) at kernel/qapplication.cpp:3178
#24 0x00007fd0fc2ea9eb in QETWidget::translateMouseEvent (this=this@entry=0x22b7ea0, event=event@entry=0x7fff1c8848c0) at kernel/qapplication_x11.cpp:4634
#25 0x00007fd0fc2ea289 in QApplication::x11ProcessEvent (this=0x7fff1c884d90, event=event@entry=0x7fff1c8848c0) at kernel/qapplication_x11.cpp:3627
#26 0x00007fd0fc311b32 in x11EventSourceDispatch (s=0x203fa90, callback=0x0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#27 0x00007fd0f3df8e04 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#28 0x00007fd0f3df9048 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#29 0x00007fd0f3df90ec in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#30 0x00007fd0fb6307a1 in QEventDispatcherGlib::processEvents (this=0x1ff2af0, flags=...) at kernel/qeventdispatcher_glib.cpp:434
#31 0x00007fd0fc311be6 in QGuiEventDispatcherGlib::processEvents (this=<optimized out>, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
#32 0x00007fd0fb6020af in QEventLoop::processEvents (this=this@entry=0x7fff1c884c90, flags=...) at kernel/qeventloop.cpp:149
#33 0x00007fd0fb6023a5 in QEventLoop::exec (this=this@entry=0x7fff1c884c90, flags=...) at kernel/qeventloop.cpp:204
#34 0x00007fd0fb607b79 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1225
#35 0x00007fd0fc26e37c in QApplication::exec () at kernel/qapplication.cpp:3828
#36 0x000000000040aadb in main (argc=1, argv=0x7fff1c884ed8) at ../../../systemsettings/app/main.cpp:49

Report to https://bugs.kde.org/