3 files changed, 11 insertions, 29 deletions

diff --git a/src/widgets/kernel/qwidget.cpp b/src/widgets/kernel/qwidget.cpp
index be9287d39b..a7258d8f7e 100644
--- a/src/widgets/kernel/qwidget.cpp
+++ b/src/widgets/kernel/qwidget.cpp
@@ -1876,39 +1876,15 @@ static void deleteBackingStore(QWidgetPrivate *d)
 {
     QTLWExtra *topData = d->topData();
 
-    // The context must be current when destroying the backing store as it may attempt to
-    // release resources like textures and shader programs. The window may not be suitable
-    // anymore as there will often not be a platform window underneath at this stage. Fall
-    // back to a QOffscreenSurface in this case.
-    QScopedPointer<QOffscreenSurface> tempSurface;
-#ifndef QT_NO_OPENGL
-    if (d->textureChildSeen && topData->shareContext) {
-        if (topData->window->handle()) {
-            topData->shareContext->makeCurrent(topData->window);
-        } else {
-            tempSurface.reset(new QOffscreenSurface);
-            tempSurface->setFormat(topData->shareContext->format());
-            tempSurface->create();
-            topData->shareContext->makeCurrent(tempSurface.data());
-        }
-    }
-#endif
-
     delete topData->backingStore;
     topData->backingStore = 0;
-
-#ifndef QT_NO_OPENGL
-    if (d->textureChildSeen && topData->shareContext)
-        topData->shareContext->doneCurrent();
-#endif
 }
 
 void QWidgetPrivate::deleteTLSysExtra()
 {
     if (extra && extra->topextra) {
         //the qplatformbackingstore may hold a reference to the window, so the backingstore
-        //needs to be deleted first. If the backingstore holds GL resources, we need to
-        // make the context current here. This is taken care of by deleteBackingStore().
+        //needs to be deleted first.
 
         extra->topextra->backingStoreTracker.destroy();
         deleteBackingStore(this);
diff --git a/src/widgets/kernel/qwidgetbackingstore.cpp b/src/widgets/kernel/qwidgetbackingstore.cpp
index bb421927db..52080fe05f 100644
--- a/src/widgets/kernel/qwidgetbackingstore.cpp
+++ b/src/widgets/kernel/qwidgetbackingstore.cpp
@@ -143,10 +143,8 @@ void QWidgetBackingStore::qt_flush(QWidget *widget, const QRegion &region, QBack
         // WA_TranslucentBackground. Therefore the compositor needs to know whether the app intends
         // to rely on translucency, in order to decide if it should clear to transparent or opaque.
         const bool translucentBackground = widget->testAttribute(Qt::WA_TranslucentBackground);
-        // Use the tlw's context, not widget's. The difference is important with native child
-        // widgets where tlw != widget.
-        backingStore->handle()->composeAndFlush(widget->windowHandle(), effectiveRegion, offset, widgetTextures,
-                                                tlw->d_func()->shareContext(), translucentBackground);
+        backingStore->handle()->composeAndFlush(widget->windowHandle(), effectiveRegion, offset,
+                                                widgetTextures, translucentBackground);
         widget->window()->d_func()->sendComposeStatus(widget->window(), true);
     } else
 #endif
diff --git a/src/widgets/kernel/qwidgetwindow.cpp b/src/widgets/kernel/qwidgetwindow.cpp
index d30154410c..319eccf223 100644
--- a/src/widgets/kernel/qwidgetwindow.cpp
+++ b/src/widgets/kernel/qwidgetwindow.cpp
@@ -96,6 +96,7 @@ public:
     }
 
     QRectF closestAcceptableGeometry(const QRectF &rect) const Q_DECL_OVERRIDE;
+    QOpenGLContext *shareContext() const override;
 };
 
 QRectF QWidgetWindowPrivate::closestAcceptableGeometry(const QRectF &rect) const
@@ -127,6 +128,13 @@ QRectF QWidgetWindowPrivate::closestAcceptableGeometry(const QRectF &rect) const
     return result;
 }
 
+QOpenGLContext *QWidgetWindowPrivate::shareContext() const
+{
+    Q_Q(const QWidgetWindow);
+    const QWidgetPrivate *widgetPrivate = QWidgetPrivate::get(q->widget());
+    return widgetPrivate->shareContext();
+}
+
 QWidgetWindow::QWidgetWindow(QWidget *widget)
     : QWindow(*new QWidgetWindowPrivate(), 0)
     , m_widget(widget)