Application: kwin_x11 (5.5.4)

Qt Version: 5.5.1
Operating System: Linux 4.4.3-300.fc23.x86_64 x86_64
Distribution: "Fedora release 23 (Twenty Three)"

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

PC was left alone to idle, and the screensaver was disabled. I only switced off the monitor.

The crash can be reproduced every time.

-- Backtrace:
Application: KWin (kwin_x11), signal: Segmentation fault
Using host libthread_db library "/lib64/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f4502fcf940 (LWP 13259))]

Thread 3 (Thread 0x7f44d9a31700 (LWP 13262)):
#0  0x00007f44f7ec2d63 in select () at /lib64/libc.so.6
#1  0x00007f44f941f52f in qt_safe_select(int, fd_set*, fd_set*, fd_set*, timespec const*) () at /lib64/libQt5Core.so.5
#2  0x00007f44f942102e in QEventDispatcherUNIXPrivate::doSelect(QFlags<QEventLoop::ProcessEventsFlag>, timespec*) () at /lib64/libQt5Core.so.5
#3  0x00007f44f942155e in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib64/libQt5Core.so.5
#4  0x00007f44f93caeca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib64/libQt5Core.so.5
#5  0x00007f44f91e7434 in QThread::exec() () at /lib64/libQt5Core.so.5
#6  0x00007f4500bf89b5 in QQmlThreadPrivate::run() () at /lib64/libQt5Qml.so.5
#7  0x00007f44f91ec3de in QThreadPrivate::start(void*) () at /lib64/libQt5Core.so.5
#8  0x00007f44fb5b260a in start_thread () at /lib64/libpthread.so.0
#9  0x00007f44f7ecca4d in clone () at /lib64/libc.so.6

Thread 2 (Thread 0x7f44d2dba700 (LWP 13264)):
#0  0x00007f44fb5b7b10 in pthread_cond_wait@@GLIBC_2.3.2 () at /lib64/libpthread.so.0
#1  0x00007f4501db6514 in QTWTF::TCMalloc_PageHeap::scavengerThread() () at /lib64/libQt5Script.so.5
#2  0x00007f4501db6559 in  () at /lib64/libQt5Script.so.5
#3  0x00007f44fb5b260a in start_thread () at /lib64/libpthread.so.0
#4  0x00007f44f7ecca4d in clone () at /lib64/libc.so.6

Thread 1 (Thread 0x7f4502fcf940 (LWP 13259)):
[KCrash Handler]
#4  0x00007f44e185655c in QXcbScreen::mapFromNative(QPoint const&) const () at /lib64/libQt5XcbQpa.so.5
#5  0x00007f44e185e9ba in QXcbWindow::handleEnterNotifyEvent(xcb_enter_notify_event_t const*) () at /lib64/libQt5XcbQpa.so.5
#6  0x00007f44e1847afd in QXcbConnection::handleXcbEvent(xcb_generic_event_t*) () at /lib64/libQt5XcbQpa.so.5
#7  0x00007f44e1848433 in QXcbConnection::processXcbEvents() () at /lib64/libQt5XcbQpa.so.5
#8  0x00007f44f93fd161 in QObject::event(QEvent*) () at /lib64/libQt5Core.so.5
#9  0x00007f44fa0b241c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /lib64/libQt5Widgets.so.5
#10 0x00007f44fa0b78e6 in QApplication::notify(QObject*, QEvent*) () at /lib64/libQt5Widgets.so.5
#11 0x00007f44f93cd73b in QCoreApplication::notifyInternal(QObject*, QEvent*) () at /lib64/libQt5Core.so.5
#12 0x00007f44f93cfb36 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () at /lib64/libQt5Core.so.5
#13 0x00007f44f9421422 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib64/libQt5Core.so.5
#14 0x00007f44e18ac96d in QUnixEventDispatcherQPA::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib64/libQt5XcbQpa.so.5
#15 0x00007f44f93caeca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib64/libQt5Core.so.5
#16 0x00007f44f93d2fac in QCoreApplication::exec() () at /lib64/libQt5Core.so.5
#17 0x00007f4502cd6c33 in kdemain () at /lib64/libkdeinit5_kwin_x11.so
#18 0x00007f44f7dea580 in __libc_start_main () at /lib64/libc.so.6
#19 0x0000561bdb905d99 in _start ()

Possible duplicates by query: bug 358370, bug 355937, bug 355585.

Reported using DrKonqi