Uploaded image for project: 'Qt'
  1. Qt
  2. QTBUG-71062

Qt application crashes showing a QDialog from a popup

    XMLWordPrintable

    Details

    • Platform/s:
      Windows
    • Commits:
      a545b85bdd8d227c63dda07728de4d1bac285cf5 (qt/qtbase/5.12)

      Description

      When a QDialog, created from a Qt::Popup is closed, this may trigger a crash.
      The crash comes from that the popup is destroyed just before the QDialog is shown.
      Unfortunately a pointer to that popup is kept and reused later into the event loop.

      See attachment to reproduce.

      1   QtSharedPointer::ExternalRefCountData::getAndRef      qsharedpointer.cpp             1328 0x66acc6a9 
      2   QWeakPointer<QObject>::QWeakPointer<QObject><QObject> qsharedpointer_impl.h          705  0x64c89879 
      3   QWeakPointer<QObject>::assign<QObject>                qsharedpointer_impl.h          701  0x64c8b267 
      4   QPointer<QWidget>::operator=                          qpointer.h                     77   0x64cb1213 
      5   QWidgetWindow::handleMouseEvent                       qwidgetwindow.cpp              507  0x64d2ee1a 
      6   QWidgetWindow::event                                  qwidgetwindow.cpp              234  0x64d2e39f 
      7   QApplicationPrivate::notify_helper                    qapplication.cpp               3804 0x64ca958b 
      8   QApplication::notify                                  qapplication.cpp               3163 0x64ca577e 
      9   QCoreApplication::notifyInternal2                     qcoreapplication.cpp           1015 0x66c8d09c 
      10  QCoreApplication::sendSpontaneousEvent                qcoreapplication.h             228  0x66db4558 
      11  QGuiApplicationPrivate::processMouseEvent             qguiapplication.cpp            1887 0xf26aa10  
      12  QGuiApplicationPrivate::processWindowSystemEvent      qguiapplication.cpp            1671 0xf26cab9  
      13  QWindowSystemInterface::sendWindowSystemEvents        qwindowsysteminterface.cpp     654  0xf23c509  
      14  QWindowsGuiEventDispatcher::sendPostedEvents          qwindowsguieventdispatcher.cpp 76   0xffe606d  
      15  qt_internal_proc                                      qeventdispatcher_win.cpp       438  0x66d223a6 
      16  AddClipboardFormatListener                            USER32                              0x185be6b  
      17  DispatchMessageW                                      USER32                              0x185833a  
      18  DispatchMessageW                                      USER32                              0x1857bee  
      19  DispatchMessageW                                      USER32                              0x18579d0  
      20  QEventDispatcherWin32::processEvents                  qeventdispatcher_win.cpp       838  0x66d22d26 
      ... <plus>                                                                                               
      

      A workaround is to set the Qt::WA_DeleteOnClose attribute on the popup (which, in some cases is not what the developer wants).

      Maybe using QPointer<QWidget> receiver = activePopupWidget on QWidgetWindow::handleMouseEvent may avoid the crash ?

        Attachments

        No reviews matched the request. Check your Options in the drop-down menu of this sections header.

          Activity

            People

            Assignee:
            richard Richard Moe Gustavsen
            Reporter:
            e.jorge Jorge Emmanuel
            Votes:
            0 Vote for this issue
            Watchers:
            2 Start watching this issue

              Dates

              Created:
              Updated:
              Resolved:

                Gerrit Reviews

                There are no open Gerrit changes