From c0847e91444e701ac176e088a81a01f61f885835 Mon Sep 17 00:00:00 2001
From: Gunnar Sletta <gunnar.sletta@jollamobile.com>
Date: Mon, 30 Jun 2014 11:14:52 +0200
Subject: [PATCH] Avoid crashing race condition.

Change-Id: I940bcbc509a689804a02f71af45f5efc19bccf9f
Reviewed-by: Giulio Camuffo <giulio.camuffo@jollamobile.com>
---
 src/plugins/platforms/wayland/qwaylandwindow.cpp | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/plugins/platforms/wayland/qwaylandwindow.cpp b/src/plugins/platforms/wayland/qwaylandwindow.cpp
index 9a7b7f09eb0..d04e76b503d 100644
--- a/src/plugins/platforms/wayland/qwaylandwindow.cpp
+++ b/src/plugins/platforms/wayland/qwaylandwindow.cpp
@@ -54,6 +54,7 @@
 #include "qwaylandwindowmanagerintegration_p.h"
 
 #include <QtCore/QFileInfo>
+#include <QtCore/QPointer>
 #include <QtGui/QWindow>
 
 #include <QGuiApplication>
@@ -245,9 +246,14 @@ void QWaylandWindow::setVisible(bool visible)
         // QWaylandShmBackingStore::beginPaint().
     } else {
         QWindowSystemInterface::handleExposeEvent(window(), QRegion());
+        // when flushing the event queue, it could contain a close event, in which
+        // case 'this' will be deleted. When that happens, we must abort right away.
+        QPointer<QWaylandWindow> deleteGuard(this);
         QWindowSystemInterface::flushWindowSystemEvents();
-        attach(static_cast<QWaylandBuffer *>(0), 0, 0);
-        commit();
+        if (!deleteGuard.isNull()) {
+            attach(static_cast<QWaylandBuffer *>(0), 0, 0);
+            commit();
+        }
     }
 }