Merge remote-tracking branch 'origin/stable' into dev

Conflicts:
	mkspecs/features/qt.prf
	src/plugins/platforms/xcb/qxcbwindow.h
	src/tools/qdoc/qdocindexfiles.cpp
	src/widgets/kernel/qwidget_qpa.cpp

Change-Id: I214f57b03bc2ff86cf3b7dfe2966168af93a5a67

1 files changed, 9 insertions, 0 deletions

diff --git a/src/plugins/platforms/xcb/qglxintegration.cpp b/src/plugins/platforms/xcb/qglxintegration.cpp
index c18764a4bb..df929c4b61 100644
--- a/src/plugins/platforms/xcb/qglxintegration.cpp
+++ b/src/plugins/platforms/xcb/qglxintegration.cpp
@@ -516,6 +516,15 @@ void QGLXContext::swapBuffers(QPlatformSurface *surface)
     else
         glxDrawable = static_cast<QXcbWindow *>(surface)->xcb_window();
     glXSwapBuffers(DISPLAY_FROM_XCB(m_screen), glxDrawable);
+
+    if (surface->surface()->surfaceClass() == QSurface::Window) {
+        QXcbWindow *platformWindow = static_cast<QXcbWindow *>(surface);
+        // OpenGL context might be bound to a non-gui thread
+        // use QueuedConnection to sync the window from the platformWindow's thread
+        // as QXcbWindow is no QObject, a wrapper slot in QXcbConnection is used.
+        if (platformWindow->needsSync())
+            QMetaObject::invokeMethod(m_screen->connection(), "syncWindow", Qt::QueuedConnection, Q_ARG(QXcbWindow*, platformWindow));
+    }
 }
 
 void (*QGLXContext::getProcAddress(const QByteArray &procName)) ()