Segfault in QQuickWidget::resizeEvent on Windows

Following patch applied to qtdeclarative:

diff --git a/src/quick/scenegraph/coreapi/qsgbatchrenderer.cpp b/src/quick/scenegraph/coreapi/qsgbatchrenderer.cpp
index 5c83528..bc67a5e 100644
— a/src/quick/scenegraph/coreapi/qsgbatchrenderer.cpp
+++ b/src/quick/scenegraph/coreapi/qsgbatchrenderer.cpp
@@ -813,6 +813,8 @@ Renderer::Renderer(QSGRenderContext *ctx)

// If rendering with an OpenGL Core profile context, we need to create a VAO
// to hold our vertex specification state.
+ Q_ASSERT(context());
+ Q_ASSERT(context()->openglContext()); //<=== this triggers
if (context()>openglContext()>format().profile() == QSurfaceFormat::CoreProfile) {
m_vao = new QOpenGLVertexArrayObject(this);
m_vao->create();

Backtrace:

Qt5Cored.dll!qt_message_fatal(QtMsgType __formal, const QMessageLogContext & context, const QString & message) Line 1357 C++
Qt5Cored.dll!QMessageLogger::fatal(const char * msg, ...) Line 669 + 0xf bytes C++
Qt5Cored.dll!qt_assert(const char * assertion, const char * file, int line) Line 2127 + 0x2e bytes C++
Qt5Quickd.dll!QSGBatchRenderer::Renderer::Renderer(QSGRenderContext * ctx) Line 817 + 0x28 bytes C++
Qt5Quickd.dll!QSGRenderContext::createRenderer() Line 580 + 0x22 bytes C++
Qt5Quickd.dll!QQuickWindowPrivate::syncSceneGraph() Line 343 + 0x19 bytes C++
Qt5Quickd.dll!QQuickRenderControl::sync() Line 161 C++
Qt5QuickWidgetsd.dll!QQuickWidget::resizeEvent(QResizeEvent * e) Line 875 C++
Qt5Widgetsd.dll!QWidget::event(QEvent * event) Line 8121 C++
Qt5QuickWidgetsd.dll!QQuickWidget::event(QEvent * e) Line 1036 C++
Qt5Widgetsd.dll!QApplicationPrivate::notify_helper(QObject * receiver, QEvent * e) Line 3522 + 0x11 bytes C++
Qt5Widgetsd.dll!QApplication::notify(QObject * receiver, QEvent * e) Line 3487 + 0x10 bytes C++
Qt5Cored.dll!QCoreApplication::notifyInternal(QObject * receiver, QEvent * event) Line 935 + 0x15 bytes C++
Qt5Cored.dll!QCoreApplication::sendEvent(QObject * receiver, QEvent * event) Line 237 + 0x39 bytes C++
Qt5Widgetsd.dll!QWidgetPrivate::sendPendingMoveAndResizeEvents(bool recursive, bool disableUpdates) Line 7072 + 0xe bytes C++
Qt5Widgetsd.dll!QWidgetPrivate::show_helper() Line 7126 C++
Qt5Widgetsd.dll!QWidgetPrivate::show_recursive() Line 7054 C++
Qt5Widgetsd.dll!QWidgetPrivate::showChildren(bool spontaneous) Line 7471 C++
Qt5Widgetsd.dll!QWidgetPrivate::show_helper() Line 7136 C++
Qt5Widgetsd.dll!QWidget::setVisible(bool visible) Line 7391 C++
Qt5Widgetsd.dll!QWidget::show() Line 7031 C++
Qt5Widgetsd.dll!QWidgetPrivate::showChildren(bool spontaneous) Line 7474 C++
Qt5Widgetsd.dll!QWidgetPrivate::show_helper() Line 7136 C++
Qt5Widgetsd.dll!QWidget::setVisible(bool visible) Line 7391 C++
Qt5Widgetsd.dll!QWidget::show() Line 7031 C++
Qt5Widgetsd.dll!QWidgetPrivate::showChildren(bool spontaneous) Line 7474 C++
Qt5Widgetsd.dll!QWidgetPrivate::show_helper() Line 7136 C++
Qt5Widgetsd.dll!QWidgetPrivate::show_recursive() Line 7054 C++
Qt5Widgetsd.dll!QWidgetPrivate::showChildren(bool spontaneous) Line 7471 C++
Qt5Widgetsd.dll!QWidgetPrivate::show_helper() Line 7136 C++
Qt5Widgetsd.dll!QWidget::setVisible(bool visible) Line 7391 C++
Qt5Widgetsd.dll!QWidget::show() Line 7031 C++
Qt5Widgetsd.dll!QStackedLayout::setCurrentIndex(int index) Line 337 C++
Cored.dll!Core::Internal::FancyTabWidget::showWidget(int index) Line 514 C++

Background:

A QtCreator plugin that does something like
myWidget->layout()->removeWidget(myQtQuickWidget1);
myWidget->layout()->addWidget(myQtQuickWidget2);
myWidget->layout()->removeWidget(myQtQuickWidget2);
myWidget->layout()->addWidget(myQtQuickWidget1);

Note that the calls above may happen while myQtQuickWidget* are not visible. The segfault only happens once QtCreator mode is switched (from "Edit" to "Design") and the current myQtQuickWidget* becomes visible, in which case another removeWidget/addWidget-sequence is triggered which leads to the segfault.