This issue occurs under unspecified circumstances.
Bug trace:
" "[New LWP 3858]
[New LWP 3859]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1". 0x00007fa86db85b57 in waitpid () from /lib64/libpthread.so.0
#0 0x00007fa86db85b57 in waitpid () at /lib64/libpthread.so.0
#1 0x000000000043b45f in crashTrapper(int) (sig=11) at tupcrashhandler.cpp:321
#2 0x00007fa86db86270 in
() at /lib64/libpthread.so.0 #3 0x00007fa87192ac66 in TupScene::layersCount() const (this=0x68007300750070) at tupscene.cpp:111 #4 0x00007fa871439a98 in TupGraphicsScene::currentFrame() (this=0x2400960) at tupgraphicsscene.cpp:1159 #5 0x00007fa8731cc017 in TupPaintArea::mousePressEvent(QMouseEvent*) (this=0x3457ea0, event=0x7ffe2386ae80) at tuppaintarea.cpp:141 #6 0x00007fa86fa67ec9 in QWidget::event(QEvent*) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/lib/libQt5Widgets.so.5 #7 0x00007fa86fb0b76e in QFrame::event(QEvent*) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/lib/libQt5Widgets.so.5 #8 0x00007fa86fd4050b in QGraphicsView::viewportEvent(QEvent*) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/lib/libQt5Widgets.so.5 #9 0x00007fa871430351 in TupPaintAreaBase::viewportEvent(QEvent*) (this=0x3457ea0, event=0x7ffe2386ae80) at tuppaintareabase.cpp:334 #10 0x00007fa86e295c2d in QCoreApplicationPrivate::sendThroughObjectEventFilters(QObject*, QEvent*) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/lib/libQt5Core.so.5 #11 0x00007fa86fa296d5 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/lib/libQt5Widgets.so.5 #12 0x00007fa86fa30dcf in QApplication::notify(QObject*, QEvent*) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/lib/libQt5Widgets.so.5 #13 0x00007fa86e295e98 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/lib/libQt5Core.so.5 #14 0x00007fa86fa2fd0a in QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool, bool) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/lib/libQt5Widgets.so.5 #15 0x00007fa86fa80e71 in QWidgetWindow::handleMouseEvent(QMouseEvent*) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/lib/libQt5Widgets.so.5 #16 0x00007fa86fa83b2b in QWidgetWindow::event(QEvent*) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/lib/libQt5Widgets.so.5 #17 0x00007fa86fa296fc in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/lib/libQt5Widgets.so.5 #18 0x00007fa86fa307f0 in QApplication::notify(QObject*, QEvent*) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/lib/libQt5Widgets.so.5 #19 0x00007fa86e295e98 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/lib/libQt5Core.so.5 #20 0x00007fa86eede727 in QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent*) () at /home/xtingray/Qt5.12.2/5.12.2/gcc_64/