Application: kdenlive (17.12.0)
 (Compiled from sources)
Qt Version: 5.9.3
Frameworks Version: 5.41.0
Operating System: Linux 4.14.7-gentoo x86_64
Distribution: "NAME=Gentoo"

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

Give-or-take some extra random moves (since I'm almost a first-time-user) I opened kdenlive, added a video clip to the untitled/unsaved project, removed all tracks except one video track, moved the clip to the video track, perhaps moved it back and forth a bit. Browsed some effects menu items for search of something. Finally, I closed the application using the [X] button on the window decoration. I don't remember whether there was a dialog asking to save the project, but eventually the crash reporting assistant popped up in the system tray, and now I'm writing this crash report in the assistant.

-- Backtrace:
Application: Kdenlive (kdenlive), signal: Segmentation fault
Using host libthread_db library "/lib64/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f63b07637c0 (LWP 6695))]

Thread 9 (Thread 0x7f636c34d700 (LWP 6846)):
#0  0x00007f63a833246b in futex_reltimed_wait_cancelable (private=<optimized out>, reltime=0x7f636c34cca0, expected=0, futex_word=0x7f637002df30) at ../sysdeps/unix/sysv/linux/futex-internal.h:142
#1  __pthread_cond_wait_common (abstime=0x7f636c34cd50, mutex=0x7f637002dee0, cond=0x7f637002df08) at pthread_cond_wait.c:533
#2  __pthread_cond_timedwait (cond=0x7f637002df08, mutex=0x7f637002dee0, abstime=0x7f636c34cd50) at pthread_cond_wait.c:667
#3  0x00007f63aaa518f8 in QWaitConditionPrivate::wait_relative (time=30000, this=0x7f637002dee0) at thread/qwaitcondition_unix.cpp:133
#4  QWaitConditionPrivate::wait (time=30000, this=0x7f637002dee0) at thread/qwaitcondition_unix.cpp:141
#5  QWaitCondition::wait (this=this@entry=0x7f6370092980, mutex=mutex@entry=0x55c7b2e4b650, time=30000) at thread/qwaitcondition_unix.cpp:215
#6  0x00007f63aaa4bfa8 in QThreadPoolThread::run (this=0x7f6370092970) at thread/qthreadpool.cpp:144
#7  0x00007f63aaa51071 in QThreadPrivate::start (arg=0x7f6370092970) at thread/qthread_unix.cpp:368
#8  0x00007f63a832aac6 in start_thread (arg=0x7f636c34d700) at pthread_create.c:465
#9  0x00007f63a9f4555f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 8 (Thread 0x7f636b247700 (LWP 6839)):
#0  0x00007f63a833246b in futex_reltimed_wait_cancelable (private=<optimized out>, reltime=0x7f636b246ca0, expected=0, futex_word=0x55c7b29084c4) at ../sysdeps/unix/sysv/linux/futex-internal.h:142
#1  __pthread_cond_wait_common (abstime=0x7f636b246d50, mutex=0x55c7b2908470, cond=0x55c7b2908498) at pthread_cond_wait.c:533
#2  __pthread_cond_timedwait (cond=0x55c7b2908498, mutex=0x55c7b2908470, abstime=0x7f636b246d50) at pthread_cond_wait.c:667
#3  0x00007f63aaa518f8 in QWaitConditionPrivate::wait_relative (time=30000, this=0x55c7b2908470) at thread/qwaitcondition_unix.cpp:133
#4  QWaitConditionPrivate::wait (time=30000, this=0x55c7b2908470) at thread/qwaitcondition_unix.cpp:141
#5  QWaitCondition::wait (this=this@entry=0x55c7b29381f0, mutex=mutex@entry=0x55c7b2e4b650, time=30000) at thread/qwaitcondition_unix.cpp:215
#6  0x00007f63aaa4bfa8 in QThreadPoolThread::run (this=0x55c7b29381e0) at thread/qthreadpool.cpp:144
#7  0x00007f63aaa51071 in QThreadPrivate::start (arg=0x55c7b29381e0) at thread/qthread_unix.cpp:368
#8  0x00007f63a832aac6 in start_thread (arg=0x7f636b247700) at pthread_create.c:465
#9  0x00007f63a9f4555f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 7 (Thread 0x7f636d34f700 (LWP 6710)):
#0  0x00007f63a9f34549 in __GI___libc_read (fd=26, buf=buf@entry=0x7f636d34eba0, nbytes=nbytes@entry=16) at ../sysdeps/unix/sysv/linux/read.c:26
#1  0x00007f63a4d6fe50 in read (__nbytes=16, __buf=0x7f636d34eba0, __fd=<optimized out>) at /usr/include/bits/unistd.h:44
#2  g_wakeup_acknowledge (wakeup=0x7f6360003d50) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gwakeup.c:210
#3  0x00007f63a4d1b95e in g_main_context_check (context=context@entry=0x7f6354000be0, max_priority=2147483647, fds=fds@entry=0x7f6354002de0, n_fds=n_fds@entry=1) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3707
#4  0x00007f63a4d1be48 in g_main_context_iterate (context=context@entry=0x7f6354000be0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3926
#5  0x00007f63a4d1c00b in g_main_context_iteration (context=0x7f6354000be0, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3990
#6  0x00007f63aacb117b in QEventDispatcherGlib::processEvents (this=0x7f6354000b10, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#7  0x00007f63aac47102 in QEventLoop::exec (this=this@entry=0x7f636d34ede0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:212
#8  0x00007f63aaa49f4e in QThread::exec (this=<optimized out>) at thread/qthread.cpp:515
#9  0x00007f63aaa51071 in QThreadPrivate::start (arg=0x55c7b5779d20) at thread/qthread_unix.cpp:368
#10 0x00007f63a832aac6 in start_thread (arg=0x7f636d34f700) at pthread_create.c:465
#11 0x00007f63a9f4555f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 6 (Thread 0x7f636e351700 (LWP 6708)):
#0  g_mutex_lock (mutex=mutex@entry=0x7f635c000be0) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gthread-posix.c:1334
#1  0x00007f63a4d1be66 in g_main_context_iterate (context=context@entry=0x7f635c000be0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3933
#2  0x00007f63a4d1c00b in g_main_context_iteration (context=0x7f635c000be0, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3990
#3  0x00007f63aacb117b in QEventDispatcherGlib::processEvents (this=0x7f635c000b10, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#4  0x00007f63aac47102 in QEventLoop::exec (this=this@entry=0x7f636e350de0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:212
#5  0x00007f63aaa49f4e in QThread::exec (this=<optimized out>) at thread/qthread.cpp:515
#6  0x00007f63aaa51071 in QThreadPrivate::start (arg=0x55c7b573dd90) at thread/qthread_unix.cpp:368
#7  0x00007f63a832aac6 in start_thread (arg=0x7f636e351700) at pthread_create.c:465
#8  0x00007f63a9f4555f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7f637c8f1700 (LWP 6702)):
#0  0x00007f63a9f38f84 in __GI___poll (fds=0x7f6374002de0, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f63a4d1bea4 in g_main_context_poll (priority=2147483647, n_fds=1, fds=0x7f6374002de0, timeout=<optimized out>, context=0x7f6374000be0) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:4228
#2  g_main_context_iterate (context=context@entry=0x7f6374000be0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3924
#3  0x00007f63a4d1c00b in g_main_context_iteration (context=0x7f6374000be0, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3990
#4  0x00007f63aacb117b in QEventDispatcherGlib::processEvents (this=0x7f6374000b10, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#5  0x00007f63aac47102 in QEventLoop::exec (this=this@entry=0x7f637c8f0db0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:212
#6  0x00007f63aaa49f4e in QThread::exec (this=this@entry=0x55c7b2819290) at thread/qthread.cpp:515
#7  0x00007f63ab948984 in QQmlThreadPrivate::run (this=0x55c7b2819290) at qml/ftw/qqmlthread.cpp:147
#8  0x00007f63aaa51071 in QThreadPrivate::start (arg=0x55c7b2819290) at thread/qthread_unix.cpp:368
#9  0x00007f63a832aac6 in start_thread (arg=0x7f637c8f1700) at pthread_create.c:465
#10 0x00007f63a9f4555f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7f637e5ac700 (LWP 6700)):
#0  g_mutex_unlock (mutex=0x7f6378000be0) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gthread-posix.c:1348
#1  0x00007f63a4d1b380 in g_main_context_prepare (context=context@entry=0x7f6378000be0, priority=priority@entry=0x7f637e5abc50) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3499
#2  0x00007f63a4d1bdd3 in g_main_context_iterate (context=context@entry=0x7f6378000be0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3909
#3  0x00007f63a4d1c00b in g_main_context_iteration (context=0x7f6378000be0, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3990
#4  0x00007f63aacb117b in QEventDispatcherGlib::processEvents (this=0x7f6378000b10, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#5  0x00007f63aac47102 in QEventLoop::exec (this=this@entry=0x7f637e5abdb0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:212
#6  0x00007f63aaa49f4e in QThread::exec (this=this@entry=0x55c7b2d59fb0) at thread/qthread.cpp:515
#7  0x00007f63ab948984 in QQmlThreadPrivate::run (this=0x55c7b2d59fb0) at qml/ftw/qqmlthread.cpp:147
#8  0x00007f63aaa51071 in QThreadPrivate::start (arg=0x55c7b2d59fb0) at thread/qthread_unix.cpp:368
#9  0x00007f63a832aac6 in start_thread (arg=0x7f637e5ac700) at pthread_create.c:465
#10 0x00007f63a9f4555f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7f6393871700 (LWP 6699)):
#0  0x00007f63aaa451f8 in std::__atomic_base<QMutexData*>::compare_exchange_strong (__m2=std::memory_order_relaxed, __m1=std::memory_order_release, __p2=0x0, __p1=@0x7f6393870b28: 0x1, this=0x55c7b1f8b8c0) at /usr/lib/gcc/x86_64-pc-linux-gnu/6.4.0/include/g++-v6/bits/atomic_base.h:752
#1  std::atomic<QMutexData*>::compare_exchange_strong (__m2=std::memory_order_relaxed, __m1=std::memory_order_release, __p2=0x0, __p1=@0x7f6393870b28: 0x1, this=0x55c7b1f8b8c0) at /usr/lib/gcc/x86_64-pc-linux-gnu/6.4.0/include/g++-v6/atomic:466
#2  QAtomicOps<QMutexData*>::testAndSetRelease<QMutexData*> (currentValue=<synthetic pointer>, newValue=0x0, expectedValue=0x1, _q_value=...) at ../../include/QtCore/../../src/corelib/arch/qatomic_cxx11.h:299
#3  QBasicAtomicPointer<QMutexData>::testAndSetRelease (currentValue=<synthetic pointer>: <optimized out>, newValue=0x0, expectedValue=<optimized out>, this=0x55c7b1f8b8c0) at ../../include/QtCore/../../src/corelib/thread/qbasicatomic.h:264
#4  QBasicMutex::fastTryUnlock (current=<synthetic pointer>: <optimized out>, this=0x55c7b1f8b8c0) at thread/qmutex.h:104
#5  QMutex::unlock (this=this@entry=0x55c7b1f8b8c0) at thread/qmutex.cpp:337
#6  0x00007f63aacb1015 in QMutexLocker::unlock (this=<synthetic pointer>) at ../../include/QtCore/../../src/corelib/thread/qmutex.h:213
#7  QMutexLocker::~QMutexLocker (this=<synthetic pointer>, __in_chrg=<optimized out>) at ../../include/QtCore/../../src/corelib/thread/qmutex.h:207
#8  QThreadData::canWaitLocked (this=<optimized out>) at ../../include/QtCore/5.9.3/QtCore/private/../../../../../src/corelib/thread/qthread_p.h:253
#9  postEventSourcePrepare (s=0x7f638c004b90, timeout=timeout@entry=0x7f6393870bb4) at kernel/qeventdispatcher_glib.cpp:259
#10 0x00007f63a4d1b38d in g_main_context_prepare (context=context@entry=0x7f638c000be0, priority=priority@entry=0x7f6393870c40) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3501
#11 0x00007f63a4d1bdd3 in g_main_context_iterate (context=context@entry=0x7f638c000be0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3909
#12 0x00007f63a4d1c00b in g_main_context_iteration (context=0x7f638c000be0, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.50.3-r1/work/glib-2.50.3/glib/gmain.c:3990
#13 0x00007f63aacb117b in QEventDispatcherGlib::processEvents (this=0x7f638c000b10, flags=...) at kernel/qeventdispatcher_glib.cpp:425
#14 0x00007f63aac47102 in QEventLoop::exec (this=this@entry=0x7f6393870da0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:212
#15 0x00007f63aaa49f4e in QThread::exec (this=this@entry=0x7f63b0839420 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at thread/qthread.cpp:515
#16 0x00007f63b07a7ad3 in QDBusConnectionManager::run (this=0x7f63b0839420 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at qdbusconnection.cpp:178
#17 0x00007f63aaa51071 in QThreadPrivate::start (arg=0x7f63b0839420 <(anonymous namespace)::Q_QGS__q_manager::innerFunction()::holder>) at thread/qthread_unix.cpp:368
#18 0x00007f63a832aac6 in start_thread (arg=0x7f6393871700) at pthread_create.c:465
#19 0x00007f63a9f4555f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7f639bbf9700 (LWP 6698)):
#0  0x00007f63a9f38f84 in __GI___poll (fds=fds@entry=0x7f639bbf8cd0, nfds=nfds@entry=1, timeout=timeout@entry=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f63a441fa82 in poll (__timeout=-1, __nfds=1, __fds=0x7f639bbf8cd0) at /usr/include/bits/poll2.h:46
#2  _xcb_conn_wait (c=c@entry=0x55c7b1dd2110, cond=cond@entry=0x55c7b1dd2150, vector=vector@entry=0x0, count=count@entry=0x0) at /var/tmp/portage/x11-libs/libxcb-1.12-r2/work/libxcb-1.12/src/xcb_conn.c:479
#3  0x00007f63a4422047 in xcb_wait_for_event (c=0x55c7b1dd2110) at /var/tmp/portage/x11-libs/libxcb-1.12-r2/work/libxcb-1.12/src/xcb_in.c:693
#4  0x00007f639d94c789 in QXcbEventReader::run (this=0x55c7b1ddd070) at qxcbconnection.cpp:1330
#5  0x00007f63aaa51071 in QThreadPrivate::start (arg=0x55c7b1ddd070) at thread/qthread_unix.cpp:368
#6  0x00007f63a832aac6 in start_thread (arg=0x7f639bbf9700) at pthread_create.c:465
#7  0x00007f63a9f4555f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7f63b07637c0 (LWP 6695)):
[KCrash Handler]
#6  0x00007f637ec724e0 in ?? ()
#7  0x00007f63afb22ce9 in mlt_consumer_purge (self=0x55c7b33d0620) at mlt_consumer.c:1342
#8  0x00007f63af8e79a3 in Mlt::Consumer::purge (this=<optimized out>) at MltConsumer.cpp:114
#9  0x000055c7b0691514 in Render::stop (this=0x55c7b3148a90) at /var/tmp/portage/kde-apps/kdenlive-17.12.0/work/kdenlive-17.12.0/src/renderer.cpp:697
#10 0x000055c7b05669e8 in Monitor::~Monitor (this=0x55c7b2e85450, __in_chrg=<optimized out>) at /var/tmp/portage/kde-apps/kdenlive-17.12.0/work/kdenlive-17.12.0/src/monitor/monitor.cpp:364
#11 0x000055c7b0566abc in Monitor::~Monitor (this=0x55c7b2e85450, __in_chrg=<optimized out>) at /var/tmp/portage/kde-apps/kdenlive-17.12.0/work/kdenlive-17.12.0/src/monitor/monitor.cpp:372
#12 0x000055c7b0675245 in MainWindow::~MainWindow (this=this@entry=0x55c7b22ade00, __in_chrg=<optimized out>, __vtt_parm=<optimized out>) at /var/tmp/portage/kde-apps/kdenlive-17.12.0/work/kdenlive-17.12.0/src/mainwindow.cpp:787
#13 0x000055c7b06753ac in MainWindow::~MainWindow (this=0x55c7b22ade00, __in_chrg=<optimized out>, __vtt_parm=<optimized out>) at /var/tmp/portage/kde-apps/kdenlive-17.12.0/work/kdenlive-17.12.0/src/mainwindow.cpp:792
#14 0x00007f63aac80148 in QObject::event (this=this@entry=0x55c7b22ade00, e=e@entry=0x55c7b5b85b80) at kernel/qobject.cpp:1237
#15 0x00007f63ac145143 in QWidget::event (this=this@entry=0x55c7b22ade00, event=event@entry=0x55c7b5b85b80) at kernel/qwidget.cpp:9266
#16 0x00007f63ac2818ab in QMainWindow::event (this=this@entry=0x55c7b22ade00, event=event@entry=0x55c7b5b85b80) at widgets/qmainwindow.cpp:1563
#17 0x00007f63ae397216 in KMainWindow::event (this=this@entry=0x55c7b22ade00, ev=ev@entry=0x55c7b5b85b80) at /var/tmp/portage/kde-frameworks/kxmlgui-5.41.0/work/kxmlgui-5.41.0/src/kmainwindow.cpp:865
#18 0x00007f63ae3e06a4 in KXmlGuiWindow::event (this=0x55c7b22ade00, ev=0x55c7b5b85b80) at /var/tmp/portage/kde-frameworks/kxmlgui-5.41.0/work/kxmlgui-5.41.0/src/kxmlguiwindow.cpp:119
#19 0x00007f63ac0fa88c in QApplicationPrivate::notify_helper (this=<optimized out>, receiver=0x55c7b22ade00, e=0x55c7b5b85b80) at kernel/qapplication.cpp:3722
#20 0x00007f63ac102a3a in QApplication::notify (this=0x7ffca5a38d20, receiver=0x55c7b22ade00, e=0x55c7b5b85b80) at kernel/qapplication.cpp:3481
#21 0x00007f63aac492ba in QCoreApplication::notifyInternal2 (receiver=0x55c7b22ade00, event=event@entry=0x55c7b5b85b80) at kernel/qcoreapplication.cpp:1018
#22 0x00007f63aac4cea4 in QCoreApplication::sendEvent (event=0x55c7b5b85b80, receiver=<optimized out>) at kernel/qcoreapplication.h:233
#23 QCoreApplicationPrivate::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=52, data=0x55c7b1dc2e60) at kernel/qcoreapplication.cpp:1678
#24 0x00007f63aac4d437 in QCoreApplication::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=52) at kernel/qcoreapplication.cpp:1532
#25 0x00007f63aac4d4b8 in QCoreApplicationPrivate::execCleanup (this=<optimized out>) at kernel/qcoreapplication.cpp:1313
#26 0x00007f63aac51b5c in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1295
#27 0x000055c7b0297d14 in main (argc=<optimized out>, argv=<optimized out>) at /var/tmp/portage/kde-apps/kdenlive-17.12.0/work/kdenlive-17.12.0/src/main.cpp:163

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

PS: Manually copy-pasted this report from "Crash Reporting Assistant" (drkonqi?) to bugs.kde.org, because the former seems to be broken no matter how many times I click "Retry". The .local/share/sddm/xorg-session.log file shows errors such the following:

Variant(QString, "Bug.create") 124 "Connection to host bugs.kde.org is broken."
Fatal Error: Got cmd 77, while waiting for an answer!
kioslave: ####### CRASH ###### protocol = https pid = 17979 signal = 6
QVariant(QString, "Bug.create") 143 "The process for the https://bugs.kde.org protocol died unexpectedly."
QVariant(QString, "Bug.create") 51 "There is no version named '17.12.0' in the 'kde' product."