Segfault on Drag&Drop when using optirun



  • Hello there,
    on my laptop i'm stuck with "optirun":https://wiki.ubuntu.com/Bumblebee to use the nvidia card. It always makes problems anyway but it seems it also troubles the clipboard system of Qt.

    system: Ubuntu14.04 64bit on Lenovo W530 / Nvidia Quadro K1000M / Qt 5.1.1

    Here's a basic piece of code that reproduces the problem:
    @MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent)
    {
    setMinimumSize(600,400);
    QTableWidget * t = new QTableWidget(4, 4, this);
    setCentralWidget(t);
    t->setDragDropMode(QAbstractItemView::DragDrop);
    }@

    When starting the program with optirun ./theprog, it segfaults in plugins/platforms/libqxcb.so when doing a drag action with the mouse.
    Copy/Paste with QClipboard and QMimeData works fine.
    optirun creates a new background X server, maybe that's the problem?
    Has someone else noticed this thing?

    Thanks in advance.
    Below is the relevant back-trace of the call stack.
    (Note: run optirun gdb ./theprog)

    #0 0x00007fffeb2b191b in ?? ()
    from /home/defgsus/prog/qt/5.1.1/5.1.1/gcc_64/plugins/platforms/libqxcb.so
    #1 0x00007fffeb2b1a34 in ?? ()
    from /home/defgsus/prog/qt/5.1.1/5.1.1/gcc_64/plugins/platforms/libqxcb.so
    #2 0x00007fffeb2676fd in ?? ()
    from /home/defgsus/prog/qt/5.1.1/5.1.1/gcc_64/plugins/platforms/libqxcb.so
    #3 0x00007fffeb25ad79 in ?? ()
    from /home/defgsus/prog/qt/5.1.1/5.1.1/gcc_64/plugins/platforms/libqxcb.so
    #4 0x00007ffff60d2413 in QWindow::create() ()
    from /home/defgsus/prog/qt/5.1.1/5.1.1/gcc_64/lib/libQt5Gui.so.5
    #5 0x00007ffff60c2096 in ?? ()
    from /home/defgsus/prog/qt/5.1.1/5.1.1/gcc_64/lib/libQt5Gui.so.5
    #6 0x00007ffff60c25dd in QBasicDrag::startDrag() ()
    from /home/defgsus/prog/qt/5.1.1/5.1.1/gcc_64/lib/libQt5Gui.so.5
    #7 0x00007fffeb262391 in ?? ()
    from /home/defgsus/prog/qt/5.1.1/5.1.1/gcc_64/plugins/platforms/libqxcb.so
    #8 0x00007ffff60c2c4d in QBasicDrag::drag(QDrag*) ()
    from /home/defgsus/prog/qt/5.1.1/5.1.1/gcc_64/lib/libQt5Gui.so.5
    #9 0x00007ffff60d6d72 in QDragManager::drag(QDrag*) ()
    from /home/defgsus/prog/qt/5.1.1/5.1.1/gcc_64/lib/libQt5Gui.so.5
    #10 0x00007ffff60d625c in QDrag::exec(QFlagsQt::DropAction, Qt::DropAction)
    () from /home/defgsus/prog/qt/5.1.1/5.1.1/gcc_64/lib/libQt5Gui.so.5
    #11 0x00007ffff79372fc in QAbstractItemView::startDrag(QFlagsQt::DropAction)
    () from /home/defgsus/prog/qt/5.1.1/5.1.1/gcc_64/lib/libQt5Widgets.so.5


  • Lifetime Qt Champion

    Hi and welcome to devnet,

    Since it's a special case and it goes down to lower levels of Qt, I'd recommend asking this question on the interest mailing list. You'll find there Qt's developers/maintainers (this forum is more user oriented)


Log in to reply
 

Looks like your connection to Qt Forum was lost, please wait while we try to reconnect.