Application: kwin_x11 (5.4.2)

Qt Version: 5.4.2
Operating System: Linux 4.2.0-34-generic x86_64
Distribution: Ubuntu 15.10

-- Information about the crash:
- What I was doing when the application crashed:

I was editing in Lazarus-ide 1.6.0, SourceEditor when the crash occurred. I was doing some simple editing removing unwanted parens markers around parameters in if-then statements.

-- Backtrace:
Application: KWin (kwin_x11), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f47f189d840 (LWP 2036))]

Thread 3 (Thread 0x7f47d2bb0700 (LWP 2052)):
#0  0x00007f47f13a46f3 in select () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007f47ef9f590f in qt_safe_select(int, fd_set*, fd_set*, fd_set*, timespec const*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f47ef9f740e in QEventDispatcherUNIXPrivate::doSelect(QFlags<QEventLoop::ProcessEventsFlag>, timespec*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3  0x00007f47ef9f793e in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f47ef9a075a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f47ef7be3d4 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f47ea32cf85 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#7  0x00007f47ef7c32be in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f47f09e66aa in start_thread (arg=0x7f47d2bb0700) at pthread_create.c:333
#9  0x00007f47f13ade9d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 2 (Thread 0x7f47ca879700 (LWP 2062)):
#0  0x00007f47f09ebda0 in pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007f47ee953114 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#2  0x00007f47ee953159 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#3  0x00007f47f09e66aa in start_thread (arg=0x7f47ca879700) at pthread_create.c:333
#4  0x00007f47f13ade9d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7f47f189d840 (LWP 2036)):
[KCrash Handler]
#6  0x00007f47ef9aa7c0 in QMetaObject::propertyOffset() const () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f47ef9aecd2 in QMetaObject::property(int) const () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f47ee9bae38 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#9  0x00007f47ee9bb269 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#10 0x00007f47ee8cda38 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#11 0x00007f47ee92d318 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#12 0x00007f47ee86d338 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#13 0x00007f47ee8a5f4f in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#14 0x00007f474000a842 in  ()
#15 0x0000000001df7808 in  ()
#16 0x00007f47c81f3e40 in  ()
#17 0x00007f47d0616518 in  ()
#18 0x00007f4700000003 in  ()
#19 0x00007f47d05170e8 in  ()
#20 0x00007f47ef7c1b39 in QThreadStorageData::get() const () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#21 0x00007f47d051d000 in  ()
#22 0x0000000001df7808 in  ()
#23 0x00007f47eea3bda8 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#24 0x00007f47d056bcb8 in  ()
#25 0x00007f47ee85f887 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#26 0x00007f47ee8f655b in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#27 0x00007f47ee8cda7f in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#28 0x00007f47ee9bcf27 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#29 0x00007f47ee9c58a5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#30 0x00007f47ef9d3940 in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#31 0x00007f47eef6db82 in KWin::EffectsHandler::windowClosed(KWin::EffectWindow*) () at /usr/lib/x86_64-linux-gnu/libkwineffects.so.6
#32 0x00007f47ef9d3617 in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#33 0x00007f47f100586b in  () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#34 0x00007f47f0eacc82 in  () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#35 0x00007f47f0ee7206 in  () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#36 0x00007f47f0eeb333 in  () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#37 0x00007f47f0eec6df in KWin::Workspace::workspaceEvent(xcb_generic_event_t*) () at /usr/lib/x86_64-linux-gnu/libkwin.so.5
#38 0x00007f47ef99f8ef in QAbstractEventDispatcher::filterNativeEvent(QByteArray const&, void*, long*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#39 0x00007f47db00235e in  () at /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so
#40 0x00007f47db0033b3 in  () at /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so
#41 0x00007f47ef9d4651 in QObject::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#42 0x00007f47f0270b8c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#43 0x00007f47f0276230 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#44 0x00007f47ef9a2f1b in QCoreApplication::notifyInternal(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#45 0x00007f47ef9a5057 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#46 0x00007f47ef9f7802 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#47 0x00007f47db05705d in  () at /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so
#48 0x00007f47ef9a075a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#49 0x00007f47ef9a82cc in QCoreApplication::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#50 0x00007f47f16764c4 in kdemain () at /usr/lib/x86_64-linux-gnu/libkdeinit5_kwin_x11.so
#51 0x00007f47f12c7a40 in __libc_start_main (main=0x4007a0 <main>, argc=3, argv=0x7fff4854c8e8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff4854c8d8) at libc-start.c:289
#52 0x00000000004007d9 in _start ()

Reported using DrKonqi