==11839== 
==11839== Conditional jump or move depends on uninitialised value(s)
==11839==    at 0x7E2EDAD: QPlatformBackingStore::toTexture(QRegion const&, QSize*) const (qplatformbackingstore.cpp:312)
==11839==    by 0x7E2EA86: QPlatformBackingStore::composeAndFlush(QWindow*, QRegion const&, QPoint const&, QPlatformTextureList*, QOpenGLContext*) (qplatformbackingstore.cpp:250)
==11839==    by 0xD0AC193: QXcbBackingStore::composeAndFlush(QWindow*, QRegion const&, QPoint const&, QPlatformTextureList*, QOpenGLContext*) (qxcbbackingstore.cpp:342)
==11839==    by 0x51C6EE9: QWidgetBackingStore::qt_flush(QWidget*, QRegion const&, QBackingStore*, QWidget*, QPoint const&, QPlatformTextureList*) (qwidgetbackingstore.cpp:120)
==11839==    by 0x51CC1ED: QWidgetBackingStore::flush(QWidget*) (qwidgetbackingstore.cpp:1203)
==11839==    by 0x51C77E4: QWidgetBackingStore::endPaint(QRegion const&, QBackingStore*, BeginPaintInfo*) (qwidgetbackingstore.cpp:340)
==11839==    by 0x51CC119: QWidgetBackingStore::doSync() (qwidgetbackingstore.cpp:1191)
==11839==    by 0x51CAD73: QWidgetBackingStore::sync(QWidget*, QRegion const&) (qwidgetbackingstore.cpp:956)
==11839==    by 0x51F75E9: QWidgetPrivate::syncBackingStore(QRegion const&) (qwidget.cpp:1700)
==11839==    by 0x5235D25: QWidgetWindow::handleExposeEvent(QExposeEvent*) (qwidgetwindow.cpp:730)
==11839==    by 0x5233927: QWidgetWindow::event(QEvent*) (qwidgetwindow.cpp:224)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BA656: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:2975)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x7B62ED4: QCoreApplication::sendSpontaneousEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Gui.so.5.3.2)
==11839==    by 0x7B6045B: QGuiApplicationPrivate::processExposeEvent(QWindowSystemInterfacePrivate::ExposeEvent*) (qguiapplication.cpp:2548)
==11839==    by 0x7B5C135: QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*) (qguiapplication.cpp:1586)
==11839==    by 0x7B461F8: QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qwindowsysteminterface.cpp:579)
==11839==    by 0xD11A766: QUnixEventDispatcherQPA::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qunixeventdispatcher.cpp:71)
==11839==    by 0x5D2F12F: QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:136)
==11839==    by 0x5D2F408: QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:212)
==11839==    by 0x5D32C58: QCoreApplication::exec() (qcoreapplication.cpp:1188)
==11839==    by 0x7B5BD9B: QGuiApplication::exec() (qguiapplication.cpp:1456)
==11839==    by 0x51B9E92: QApplication::exec() (qapplication.cpp:2767)
==11839==    by 0x404899: main (main.cpp:60)
==11839== 
virtual MySubWindow::~MySubWindow()
virtual MySubWindow::~MySubWindow()
virtual MyQuickWidget::~MyQuickWidget()
==11839== Invalid read of size 8
==11839==    at 0x5A92384: QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::data() const (qscopedpointer.h:143)
==11839==    by 0x5AB65E2: QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::pointer qGetPtrHelper<QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> > >(QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> > const&) (qglobal.h:945)
==11839==    by 0x5AB6601: QObject::d_func() (qobject.h:118)
==11839==    by 0x5D75E2B: QObject::setProperty(char const*, QVariant const&) (qobject.cpp:3788)
==11839==    by 0x6CBB23D: QSGRenderContext::invalidate() (qsgcontext.cpp:508)
==11839==    by 0x6CBA7B9: QSGRenderContext::~QSGRenderContext() (qsgcontext.cpp:336)
==11839==    by 0x6CBA837: QSGRenderContext::~QSGRenderContext() (qsgcontext.cpp:337)
==11839==    by 0x6D21FCA: QQuickRenderControlPrivate::~QQuickRenderControlPrivate() (qquickrendercontrol.cpp:76)
==11839==    by 0x6D22035: QQuickRenderControlPrivate::~QQuickRenderControlPrivate() (qquickrendercontrol.cpp:78)
==11839==    by 0x5D7AF1B: QScopedPointerDeleter<QObjectData>::cleanup(QObjectData*) (qscopedpointer.h:62)
==11839==    by 0x5D7945C: QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::~QScopedPointer() (qscopedpointer.h:109)
==11839==    by 0x5D6E9F8: QObject::~QObject() (qobject.cpp:880)
==11839==    by 0x6D21973: QQuickRenderControl::~QQuickRenderControl() (qquickrendercontrol.cpp:99)
==11839==    by 0x4E3F4F5: QQuickWidgetRenderControl::~QQuickWidgetRenderControl() (in /depot/fkleint/qt-5s/qtbase/lib/libQt5QuickWidgets.so.5.3.2)
==11839==    by 0x4E3F527: QQuickWidgetRenderControl::~QQuickWidgetRenderControl() (qquickwidget.cpp:71)
==11839==    by 0x4E39B9D: QQuickWidgetPrivate::~QQuickWidgetPrivate() (qquickwidget.cpp:166)
==11839==    by 0x4E39CCB: QQuickWidgetPrivate::~QQuickWidgetPrivate() (qquickwidget.cpp:171)
==11839==    by 0x5D7AF1B: QScopedPointerDeleter<QObjectData>::cleanup(QObjectData*) (qscopedpointer.h:62)
==11839==    by 0x5D7945C: QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::~QScopedPointer() (qscopedpointer.h:109)
==11839==    by 0x5D6E9F8: QObject::~QObject() (qobject.cpp:880)
==11839==    by 0x51F6C55: QWidget::~QWidget() (qwidget.cpp:1358)
==11839==    by 0x4E3A55A: QQuickWidget::~QQuickWidget() (qquickwidget.cpp:352)
==11839==    by 0x404E5F: MyQuickWidget::~MyQuickWidget() (main.cpp:9)
==11839==    by 0x404EC9: MyQuickWidget::~MyQuickWidget() (main.cpp:11)
==11839==    by 0x5D702B9: QObjectPrivate::deleteChildren() (qobject.cpp:1935)
==11839==    by 0x51F6B82: QWidget::~QWidget() (qwidget.cpp:1490)
==11839==    by 0x53762C7: QMdiSubWindow::~QMdiSubWindow() (qmdisubwindow.cpp:2275)
==11839==    by 0x405009: MySubWindow::~MySubWindow() (main.cpp:20)
==11839==    by 0x405073: MySubWindow::~MySubWindow() (main.cpp:22)
==11839==    by 0x5D77369: qDeleteInEventHandler(QObject*) (qobject.cpp:4345)
==11839==    by 0x5D6ED27: QObject::event(QEvent*) (qobject.cpp:1232)
==11839==    by 0x5208FC0: QWidget::event(QEvent*) (qwidget.cpp:8371)
==11839==    by 0x537879B: QMdiSubWindow::event(QEvent*) (qmdisubwindow.cpp:2913)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BCCE2: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:3487)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x5D3633A: QCoreApplication::sendEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Core.so.5.3.2)
==11839==    by 0x5D336A7: QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (qcoreapplication.cpp:1539)
==11839==    by 0x5DA79AD: QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qeventdispatcher_unix.cpp:587)
==11839==    by 0xD11A759: QUnixEventDispatcherQPA::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qunixeventdispatcher.cpp:70)
==11839==    by 0x5D2F12F: QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:136)
==11839==    by 0x5D2F408: QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:212)
==11839==    by 0x5D32C58: QCoreApplication::exec() (qcoreapplication.cpp:1188)
==11839==    by 0x7B5BD9B: QGuiApplication::exec() (qguiapplication.cpp:1456)
==11839==    by 0x51B9E92: QApplication::exec() (qapplication.cpp:2767)
==11839==    by 0x404899: main (main.cpp:60)
==11839==  Address 0x12264b78 is 8 bytes inside a block of size 16 free'd
==11839==    at 0x4C2A4BC: operator delete(void*) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==11839==    by 0x7BA17D1: QOpenGLContext::~QOpenGLContext() (qopenglcontext.cpp:587)
==11839==    by 0x4E3B44A: QQuickWidgetPrivate::destroyContext() (qquickwidget.cpp:661)
==11839==    by 0x4E398DF: QQuickWidgetPrivate::handleWindowChange() (qquickwidget.cpp:136)
==11839==    by 0x4E3CD73: QQuickWidget::event(QEvent*) (qquickwidget.cpp:1032)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BCCE2: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:3487)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x51AF08A: QCoreApplication::sendEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Widgets.so.5.3.2)
==11839==    by 0x520A7D4: sendWindowChangeToTextureChildrenRecursively(QWidget*) (qwidget.cpp:9602)
==11839==    by 0x520A873: sendWindowChangeToTextureChildrenRecursively(QWidget*) (qwidget.cpp:9608)
==11839==    by 0x520AFCF: QWidget::setParent(QWidget*, QFlags<Qt::WindowType>) (qwidget.cpp:9740)
==11839==    by 0x520A77D: QWidget::setParent(QWidget*) (qwidget.cpp:9593)
==11839==    by 0x5367765: QMdiArea::removeSubWindow(QWidget*) (qmdiarea.cpp:2003)
==11839==    by 0x4053DD: MainWindow::mousePressEvent(QMouseEvent*) (main.cpp:43)
==11839==    by 0x52079AA: QWidget::event(QEvent*) (qwidget.cpp:7961)
==11839==    by 0x5356AFA: QMainWindow::event(QEvent*) (qmainwindow.cpp:1499)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BADEB: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:3089)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x51BF0B2: QCoreApplication::sendSpontaneousEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Widgets.so.5.3.2)
==11839==    by 0x51B9774: QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool) (qapplication.cpp:2562)
==11839==    by 0x52349EC: QWidgetWindow::handleMouseEvent(QMouseEvent*) (qwidgetwindow.cpp:507)
==11839==    by 0x5233822: QWidgetWindow::event(QEvent*) (qwidgetwindow.cpp:179)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BA656: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:2975)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x7B62ED4: QCoreApplication::sendSpontaneousEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Gui.so.5.3.2)
==11839==    by 0x7B5C999: QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent*) (qguiapplication.cpp:1721)
==11839==    by 0x7B5BFF7: QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*) (qguiapplication.cpp:1522)
==11839==    by 0x7B461F8: QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qwindowsysteminterface.cpp:579)
==11839==    by 0xD11A766: QUnixEventDispatcherQPA::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qunixeventdispatcher.cpp:71)
==11839==    by 0x5D2F12F: QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:136)
==11839==    by 0x5D2F408: QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:212)
==11839==    by 0x5D32C58: QCoreApplication::exec() (qcoreapplication.cpp:1188)
==11839==    by 0x7B5BD9B: QGuiApplication::exec() (qguiapplication.cpp:1456)
==11839==    by 0x51B9E92: QApplication::exec() (qapplication.cpp:2767)
==11839==    by 0x404899: main (main.cpp:60)
==11839== 
==11839== Invalid read of size 8
==11839==    at 0x5D75E37: QObject::setProperty(char const*, QVariant const&) (qobject.cpp:3789)
==11839==    by 0x6CBB23D: QSGRenderContext::invalidate() (qsgcontext.cpp:508)
==11839==    by 0x6CBA7B9: QSGRenderContext::~QSGRenderContext() (qsgcontext.cpp:336)
==11839==    by 0x6CBA837: QSGRenderContext::~QSGRenderContext() (qsgcontext.cpp:337)
==11839==    by 0x6D21FCA: QQuickRenderControlPrivate::~QQuickRenderControlPrivate() (qquickrendercontrol.cpp:76)
==11839==    by 0x6D22035: QQuickRenderControlPrivate::~QQuickRenderControlPrivate() (qquickrendercontrol.cpp:78)
==11839==    by 0x5D7AF1B: QScopedPointerDeleter<QObjectData>::cleanup(QObjectData*) (qscopedpointer.h:62)
==11839==    by 0x5D7945C: QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::~QScopedPointer() (qscopedpointer.h:109)
==11839==    by 0x5D6E9F8: QObject::~QObject() (qobject.cpp:880)
==11839==    by 0x6D21973: QQuickRenderControl::~QQuickRenderControl() (qquickrendercontrol.cpp:99)
==11839==    by 0x4E3F4F5: QQuickWidgetRenderControl::~QQuickWidgetRenderControl() (in /depot/fkleint/qt-5s/qtbase/lib/libQt5QuickWidgets.so.5.3.2)
==11839==    by 0x4E3F527: QQuickWidgetRenderControl::~QQuickWidgetRenderControl() (qquickwidget.cpp:71)
==11839==    by 0x4E39B9D: QQuickWidgetPrivate::~QQuickWidgetPrivate() (qquickwidget.cpp:166)
==11839==    by 0x4E39CCB: QQuickWidgetPrivate::~QQuickWidgetPrivate() (qquickwidget.cpp:171)
==11839==    by 0x5D7AF1B: QScopedPointerDeleter<QObjectData>::cleanup(QObjectData*) (qscopedpointer.h:62)
==11839==    by 0x5D7945C: QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::~QScopedPointer() (qscopedpointer.h:109)
==11839==    by 0x5D6E9F8: QObject::~QObject() (qobject.cpp:880)
==11839==    by 0x51F6C55: QWidget::~QWidget() (qwidget.cpp:1358)
==11839==    by 0x4E3A55A: QQuickWidget::~QQuickWidget() (qquickwidget.cpp:352)
==11839==    by 0x404E5F: MyQuickWidget::~MyQuickWidget() (main.cpp:9)
==11839==    by 0x404EC9: MyQuickWidget::~MyQuickWidget() (main.cpp:11)
==11839==    by 0x5D702B9: QObjectPrivate::deleteChildren() (qobject.cpp:1935)
==11839==    by 0x51F6B82: QWidget::~QWidget() (qwidget.cpp:1490)
==11839==    by 0x53762C7: QMdiSubWindow::~QMdiSubWindow() (qmdisubwindow.cpp:2275)
==11839==    by 0x405009: MySubWindow::~MySubWindow() (main.cpp:20)
==11839==    by 0x405073: MySubWindow::~MySubWindow() (main.cpp:22)
==11839==    by 0x5D77369: qDeleteInEventHandler(QObject*) (qobject.cpp:4345)
==11839==    by 0x5D6ED27: QObject::event(QEvent*) (qobject.cpp:1232)
==11839==    by 0x5208FC0: QWidget::event(QEvent*) (qwidget.cpp:8371)
==11839==    by 0x537879B: QMdiSubWindow::event(QEvent*) (qmdisubwindow.cpp:2913)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BCCE2: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:3487)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x5D3633A: QCoreApplication::sendEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Core.so.5.3.2)
==11839==    by 0x5D336A7: QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (qcoreapplication.cpp:1539)
==11839==    by 0x5DA79AD: QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qeventdispatcher_unix.cpp:587)
==11839==    by 0xD11A759: QUnixEventDispatcherQPA::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qunixeventdispatcher.cpp:70)
==11839==    by 0x5D2F12F: QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:136)
==11839==    by 0x5D2F408: QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:212)
==11839==    by 0x5D32C58: QCoreApplication::exec() (qcoreapplication.cpp:1188)
==11839==    by 0x7B5BD9B: QGuiApplication::exec() (qguiapplication.cpp:1456)
==11839==    by 0x51B9E92: QApplication::exec() (qapplication.cpp:2767)
==11839==    by 0x404899: main (main.cpp:60)
==11839==  Address 0x12264b70 is 0 bytes inside a block of size 16 free'd
==11839==    at 0x4C2A4BC: operator delete(void*) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==11839==    by 0x7BA17D1: QOpenGLContext::~QOpenGLContext() (qopenglcontext.cpp:587)
==11839==    by 0x4E3B44A: QQuickWidgetPrivate::destroyContext() (qquickwidget.cpp:661)
==11839==    by 0x4E398DF: QQuickWidgetPrivate::handleWindowChange() (qquickwidget.cpp:136)
==11839==    by 0x4E3CD73: QQuickWidget::event(QEvent*) (qquickwidget.cpp:1032)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BCCE2: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:3487)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x51AF08A: QCoreApplication::sendEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Widgets.so.5.3.2)
==11839==    by 0x520A7D4: sendWindowChangeToTextureChildrenRecursively(QWidget*) (qwidget.cpp:9602)
==11839==    by 0x520A873: sendWindowChangeToTextureChildrenRecursively(QWidget*) (qwidget.cpp:9608)
==11839==    by 0x520AFCF: QWidget::setParent(QWidget*, QFlags<Qt::WindowType>) (qwidget.cpp:9740)
==11839==    by 0x520A77D: QWidget::setParent(QWidget*) (qwidget.cpp:9593)
==11839==    by 0x5367765: QMdiArea::removeSubWindow(QWidget*) (qmdiarea.cpp:2003)
==11839==    by 0x4053DD: MainWindow::mousePressEvent(QMouseEvent*) (main.cpp:43)
==11839==    by 0x52079AA: QWidget::event(QEvent*) (qwidget.cpp:7961)
==11839==    by 0x5356AFA: QMainWindow::event(QEvent*) (qmainwindow.cpp:1499)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BADEB: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:3089)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x51BF0B2: QCoreApplication::sendSpontaneousEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Widgets.so.5.3.2)
==11839==    by 0x51B9774: QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool) (qapplication.cpp:2562)
==11839==    by 0x52349EC: QWidgetWindow::handleMouseEvent(QMouseEvent*) (qwidgetwindow.cpp:507)
==11839==    by 0x5233822: QWidgetWindow::event(QEvent*) (qwidgetwindow.cpp:179)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BA656: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:2975)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x7B62ED4: QCoreApplication::sendSpontaneousEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Gui.so.5.3.2)
==11839==    by 0x7B5C999: QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent*) (qguiapplication.cpp:1721)
==11839==    by 0x7B5BFF7: QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*) (qguiapplication.cpp:1522)
==11839==    by 0x7B461F8: QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qwindowsysteminterface.cpp:579)
==11839==    by 0xD11A766: QUnixEventDispatcherQPA::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qunixeventdispatcher.cpp:71)
==11839==    by 0x5D2F12F: QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:136)
==11839==    by 0x5D2F408: QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:212)
==11839==    by 0x5D32C58: QCoreApplication::exec() (qcoreapplication.cpp:1188)
==11839==    by 0x7B5BD9B: QGuiApplication::exec() (qguiapplication.cpp:1456)
==11839==    by 0x51B9E92: QApplication::exec() (qapplication.cpp:2767)
==11839==    by 0x404899: main (main.cpp:60)
==11839== 
==11839== Invalid read of size 8
==11839==    at 0x5A9187E: QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::operator->() const (qscopedpointer.h:120)
==11839==    by 0x5D781BD: QObject::metaObject() const (moc_qobject.cpp:141)
==11839==    by 0x5D75E48: QObject::setProperty(char const*, QVariant const&) (qobject.cpp:3789)
==11839==    by 0x6CBB23D: QSGRenderContext::invalidate() (qsgcontext.cpp:508)
==11839==    by 0x6CBA7B9: QSGRenderContext::~QSGRenderContext() (qsgcontext.cpp:336)
==11839==    by 0x6CBA837: QSGRenderContext::~QSGRenderContext() (qsgcontext.cpp:337)
==11839==    by 0x6D21FCA: QQuickRenderControlPrivate::~QQuickRenderControlPrivate() (qquickrendercontrol.cpp:76)
==11839==    by 0x6D22035: QQuickRenderControlPrivate::~QQuickRenderControlPrivate() (qquickrendercontrol.cpp:78)
==11839==    by 0x5D7AF1B: QScopedPointerDeleter<QObjectData>::cleanup(QObjectData*) (qscopedpointer.h:62)
==11839==    by 0x5D7945C: QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::~QScopedPointer() (qscopedpointer.h:109)
==11839==    by 0x5D6E9F8: QObject::~QObject() (qobject.cpp:880)
==11839==    by 0x6D21973: QQuickRenderControl::~QQuickRenderControl() (qquickrendercontrol.cpp:99)
==11839==    by 0x4E3F4F5: QQuickWidgetRenderControl::~QQuickWidgetRenderControl() (in /depot/fkleint/qt-5s/qtbase/lib/libQt5QuickWidgets.so.5.3.2)
==11839==    by 0x4E3F527: QQuickWidgetRenderControl::~QQuickWidgetRenderControl() (qquickwidget.cpp:71)
==11839==    by 0x4E39B9D: QQuickWidgetPrivate::~QQuickWidgetPrivate() (qquickwidget.cpp:166)
==11839==    by 0x4E39CCB: QQuickWidgetPrivate::~QQuickWidgetPrivate() (qquickwidget.cpp:171)
==11839==    by 0x5D7AF1B: QScopedPointerDeleter<QObjectData>::cleanup(QObjectData*) (qscopedpointer.h:62)
==11839==    by 0x5D7945C: QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::~QScopedPointer() (qscopedpointer.h:109)
==11839==    by 0x5D6E9F8: QObject::~QObject() (qobject.cpp:880)
==11839==    by 0x51F6C55: QWidget::~QWidget() (qwidget.cpp:1358)
==11839==    by 0x4E3A55A: QQuickWidget::~QQuickWidget() (qquickwidget.cpp:352)
==11839==    by 0x404E5F: MyQuickWidget::~MyQuickWidget() (main.cpp:9)
==11839==    by 0x404EC9: MyQuickWidget::~MyQuickWidget() (main.cpp:11)
==11839==    by 0x5D702B9: QObjectPrivate::deleteChildren() (qobject.cpp:1935)
==11839==    by 0x51F6B82: QWidget::~QWidget() (qwidget.cpp:1490)
==11839==    by 0x53762C7: QMdiSubWindow::~QMdiSubWindow() (qmdisubwindow.cpp:2275)
==11839==    by 0x405009: MySubWindow::~MySubWindow() (main.cpp:20)
==11839==    by 0x405073: MySubWindow::~MySubWindow() (main.cpp:22)
==11839==    by 0x5D77369: qDeleteInEventHandler(QObject*) (qobject.cpp:4345)
==11839==    by 0x5D6ED27: QObject::event(QEvent*) (qobject.cpp:1232)
==11839==    by 0x5208FC0: QWidget::event(QEvent*) (qwidget.cpp:8371)
==11839==    by 0x537879B: QMdiSubWindow::event(QEvent*) (qmdisubwindow.cpp:2913)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BCCE2: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:3487)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x5D3633A: QCoreApplication::sendEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Core.so.5.3.2)
==11839==    by 0x5D336A7: QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (qcoreapplication.cpp:1539)
==11839==    by 0x5DA79AD: QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qeventdispatcher_unix.cpp:587)
==11839==    by 0xD11A759: QUnixEventDispatcherQPA::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qunixeventdispatcher.cpp:70)
==11839==    by 0x5D2F12F: QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:136)
==11839==    by 0x5D2F408: QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:212)
==11839==    by 0x5D32C58: QCoreApplication::exec() (qcoreapplication.cpp:1188)
==11839==    by 0x7B5BD9B: QGuiApplication::exec() (qguiapplication.cpp:1456)
==11839==    by 0x51B9E92: QApplication::exec() (qapplication.cpp:2767)
==11839==    by 0x404899: main (main.cpp:60)
==11839==  Address 0x12264b78 is 8 bytes inside a block of size 16 free'd
==11839==    at 0x4C2A4BC: operator delete(void*) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==11839==    by 0x7BA17D1: QOpenGLContext::~QOpenGLContext() (qopenglcontext.cpp:587)
==11839==    by 0x4E3B44A: QQuickWidgetPrivate::destroyContext() (qquickwidget.cpp:661)
==11839==    by 0x4E398DF: QQuickWidgetPrivate::handleWindowChange() (qquickwidget.cpp:136)
==11839==    by 0x4E3CD73: QQuickWidget::event(QEvent*) (qquickwidget.cpp:1032)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BCCE2: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:3487)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x51AF08A: QCoreApplication::sendEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Widgets.so.5.3.2)
==11839==    by 0x520A7D4: sendWindowChangeToTextureChildrenRecursively(QWidget*) (qwidget.cpp:9602)
==11839==    by 0x520A873: sendWindowChangeToTextureChildrenRecursively(QWidget*) (qwidget.cpp:9608)
==11839==    by 0x520AFCF: QWidget::setParent(QWidget*, QFlags<Qt::WindowType>) (qwidget.cpp:9740)
==11839==    by 0x520A77D: QWidget::setParent(QWidget*) (qwidget.cpp:9593)
==11839==    by 0x5367765: QMdiArea::removeSubWindow(QWidget*) (qmdiarea.cpp:2003)
==11839==    by 0x4053DD: MainWindow::mousePressEvent(QMouseEvent*) (main.cpp:43)
==11839==    by 0x52079AA: QWidget::event(QEvent*) (qwidget.cpp:7961)
==11839==    by 0x5356AFA: QMainWindow::event(QEvent*) (qmainwindow.cpp:1499)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BADEB: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:3089)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x51BF0B2: QCoreApplication::sendSpontaneousEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Widgets.so.5.3.2)
==11839==    by 0x51B9774: QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool) (qapplication.cpp:2562)
==11839==    by 0x52349EC: QWidgetWindow::handleMouseEvent(QMouseEvent*) (qwidgetwindow.cpp:507)
==11839==    by 0x5233822: QWidgetWindow::event(QEvent*) (qwidgetwindow.cpp:179)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BA656: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:2975)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x7B62ED4: QCoreApplication::sendSpontaneousEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Gui.so.5.3.2)
==11839==    by 0x7B5C999: QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent*) (qguiapplication.cpp:1721)
==11839==    by 0x7B5BFF7: QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*) (qguiapplication.cpp:1522)
==11839==    by 0x7B461F8: QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qwindowsysteminterface.cpp:579)
==11839==    by 0xD11A766: QUnixEventDispatcherQPA::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qunixeventdispatcher.cpp:71)
==11839==    by 0x5D2F12F: QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:136)
==11839==    by 0x5D2F408: QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:212)
==11839==    by 0x5D32C58: QCoreApplication::exec() (qcoreapplication.cpp:1188)
==11839==    by 0x7B5BD9B: QGuiApplication::exec() (qguiapplication.cpp:1456)
==11839==    by 0x51B9E92: QApplication::exec() (qapplication.cpp:2767)
==11839==    by 0x404899: main (main.cpp:60)
==11839== 
==11839== Invalid read of size 8
==11839==    at 0x5A918A7: QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::operator->() const (qscopedpointer.h:121)
==11839==    by 0x5D781BD: QObject::metaObject() const (moc_qobject.cpp:141)
==11839==    by 0x5D75E48: QObject::setProperty(char const*, QVariant const&) (qobject.cpp:3789)
==11839==    by 0x6CBB23D: QSGRenderContext::invalidate() (qsgcontext.cpp:508)
==11839==    by 0x6CBA7B9: QSGRenderContext::~QSGRenderContext() (qsgcontext.cpp:336)
==11839==    by 0x6CBA837: QSGRenderContext::~QSGRenderContext() (qsgcontext.cpp:337)
==11839==    by 0x6D21FCA: QQuickRenderControlPrivate::~QQuickRenderControlPrivate() (qquickrendercontrol.cpp:76)
==11839==    by 0x6D22035: QQuickRenderControlPrivate::~QQuickRenderControlPrivate() (qquickrendercontrol.cpp:78)
==11839==    by 0x5D7AF1B: QScopedPointerDeleter<QObjectData>::cleanup(QObjectData*) (qscopedpointer.h:62)
==11839==    by 0x5D7945C: QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::~QScopedPointer() (qscopedpointer.h:109)
==11839==    by 0x5D6E9F8: QObject::~QObject() (qobject.cpp:880)
==11839==    by 0x6D21973: QQuickRenderControl::~QQuickRenderControl() (qquickrendercontrol.cpp:99)
==11839==    by 0x4E3F4F5: QQuickWidgetRenderControl::~QQuickWidgetRenderControl() (in /depot/fkleint/qt-5s/qtbase/lib/libQt5QuickWidgets.so.5.3.2)
==11839==    by 0x4E3F527: QQuickWidgetRenderControl::~QQuickWidgetRenderControl() (qquickwidget.cpp:71)
==11839==    by 0x4E39B9D: QQuickWidgetPrivate::~QQuickWidgetPrivate() (qquickwidget.cpp:166)
==11839==    by 0x4E39CCB: QQuickWidgetPrivate::~QQuickWidgetPrivate() (qquickwidget.cpp:171)
==11839==    by 0x5D7AF1B: QScopedPointerDeleter<QObjectData>::cleanup(QObjectData*) (qscopedpointer.h:62)
==11839==    by 0x5D7945C: QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::~QScopedPointer() (qscopedpointer.h:109)
==11839==    by 0x5D6E9F8: QObject::~QObject() (qobject.cpp:880)
==11839==    by 0x51F6C55: QWidget::~QWidget() (qwidget.cpp:1358)
==11839==    by 0x4E3A55A: QQuickWidget::~QQuickWidget() (qquickwidget.cpp:352)
==11839==    by 0x404E5F: MyQuickWidget::~MyQuickWidget() (main.cpp:9)
==11839==    by 0x404EC9: MyQuickWidget::~MyQuickWidget() (main.cpp:11)
==11839==    by 0x5D702B9: QObjectPrivate::deleteChildren() (qobject.cpp:1935)
==11839==    by 0x51F6B82: QWidget::~QWidget() (qwidget.cpp:1490)
==11839==    by 0x53762C7: QMdiSubWindow::~QMdiSubWindow() (qmdisubwindow.cpp:2275)
==11839==    by 0x405009: MySubWindow::~MySubWindow() (main.cpp:20)
==11839==    by 0x405073: MySubWindow::~MySubWindow() (main.cpp:22)
==11839==    by 0x5D77369: qDeleteInEventHandler(QObject*) (qobject.cpp:4345)
==11839==    by 0x5D6ED27: QObject::event(QEvent*) (qobject.cpp:1232)
==11839==    by 0x5208FC0: QWidget::event(QEvent*) (qwidget.cpp:8371)
==11839==    by 0x537879B: QMdiSubWindow::event(QEvent*) (qmdisubwindow.cpp:2913)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BCCE2: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:3487)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x5D3633A: QCoreApplication::sendEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Core.so.5.3.2)
==11839==    by 0x5D336A7: QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) (qcoreapplication.cpp:1539)
==11839==    by 0x5DA79AD: QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qeventdispatcher_unix.cpp:587)
==11839==    by 0xD11A759: QUnixEventDispatcherQPA::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qunixeventdispatcher.cpp:70)
==11839==    by 0x5D2F12F: QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:136)
==11839==    by 0x5D2F408: QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:212)
==11839==    by 0x5D32C58: QCoreApplication::exec() (qcoreapplication.cpp:1188)
==11839==    by 0x7B5BD9B: QGuiApplication::exec() (qguiapplication.cpp:1456)
==11839==    by 0x51B9E92: QApplication::exec() (qapplication.cpp:2767)
==11839==    by 0x404899: main (main.cpp:60)
==11839==  Address 0x12264b78 is 8 bytes inside a block of size 16 free'd
==11839==    at 0x4C2A4BC: operator delete(void*) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==11839==    by 0x7BA17D1: QOpenGLContext::~QOpenGLContext() (qopenglcontext.cpp:587)
==11839==    by 0x4E3B44A: QQuickWidgetPrivate::destroyContext() (qquickwidget.cpp:661)
==11839==    by 0x4E398DF: QQuickWidgetPrivate::handleWindowChange() (qquickwidget.cpp:136)
==11839==    by 0x4E3CD73: QQuickWidget::event(QEvent*) (qquickwidget.cpp:1032)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BCCE2: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:3487)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x51AF08A: QCoreApplication::sendEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Widgets.so.5.3.2)
==11839==    by 0x520A7D4: sendWindowChangeToTextureChildrenRecursively(QWidget*) (qwidget.cpp:9602)
==11839==    by 0x520A873: sendWindowChangeToTextureChildrenRecursively(QWidget*) (qwidget.cpp:9608)
==11839==    by 0x520AFCF: QWidget::setParent(QWidget*, QFlags<Qt::WindowType>) (qwidget.cpp:9740)
==11839==    by 0x520A77D: QWidget::setParent(QWidget*) (qwidget.cpp:9593)
==11839==    by 0x5367765: QMdiArea::removeSubWindow(QWidget*) (qmdiarea.cpp:2003)
==11839==    by 0x4053DD: MainWindow::mousePressEvent(QMouseEvent*) (main.cpp:43)
==11839==    by 0x52079AA: QWidget::event(QEvent*) (qwidget.cpp:7961)
==11839==    by 0x5356AFA: QMainWindow::event(QEvent*) (qmainwindow.cpp:1499)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BADEB: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:3089)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x51BF0B2: QCoreApplication::sendSpontaneousEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Widgets.so.5.3.2)
==11839==    by 0x51B9774: QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool) (qapplication.cpp:2562)
==11839==    by 0x52349EC: QWidgetWindow::handleMouseEvent(QMouseEvent*) (qwidgetwindow.cpp:507)
==11839==    by 0x5233822: QWidgetWindow::event(QEvent*) (qwidgetwindow.cpp:179)
==11839==    by 0x51BCE7D: QApplicationPrivate::notify_helper(QObject*, QEvent*) (qapplication.cpp:3522)
==11839==    by 0x51BA656: QApplication::notify(QObject*, QEvent*) (qapplication.cpp:2975)
==11839==    by 0x5D3258F: QCoreApplication::notifyInternal(QObject*, QEvent*) (qcoreapplication.cpp:935)
==11839==    by 0x7B62ED4: QCoreApplication::sendSpontaneousEvent(QObject*, QEvent*) (in /depot/fkleint/qt-5s/qtbase/lib/libQt5Gui.so.5.3.2)
==11839==    by 0x7B5C999: QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent*) (qguiapplication.cpp:1721)
==11839==    by 0x7B5BFF7: QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*) (qguiapplication.cpp:1522)
==11839==    by 0x7B461F8: QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qwindowsysteminterface.cpp:579)
==11839==    by 0xD11A766: QUnixEventDispatcherQPA::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qunixeventdispatcher.cpp:71)
==11839==    by 0x5D2F12F: QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:136)
==11839==    by 0x5D2F408: QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (qeventloop.cpp:212)
==11839==    by 0x5D32C58: QCoreApplication::exec() (qcoreapplication.cpp:1188)
==11839==    by 0x7B5BD9B: QGuiApplication::exec() (qguiapplication.cpp:1456)
==11839==    by 0x51B9E92: QApplication::exec() (qapplication.cpp:2767)
==11839==    by 0x404899: main (main.cpp:60)
==11839==