From 124da0f5e6733b0f9f87367306c6d7c0b9513685 Mon Sep 17 00:00:00 2001
From: Shawn Rutledge <shawn.rutledge@digia.com>
Date: Tue, 30 Apr 2013 10:59:15 +0200
Subject: [PATCH] Fix possible segfault when setting up window's transient
 parent

tp->handle() can be null.

Task-number: QTBUG-30919
Change-Id: Ie18b70d4cc6916d2e821a71d00d1bf99956b0632
Reviewed-by: Liang Qi <liang.qi@digia.com>
---
 src/plugins/platforms/xcb/qxcbwindow.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/plugins/platforms/xcb/qxcbwindow.cpp b/src/plugins/platforms/xcb/qxcbwindow.cpp
index c845b875bf..6291396e6e 100644
--- a/src/plugins/platforms/xcb/qxcbwindow.cpp
+++ b/src/plugins/platforms/xcb/qxcbwindow.cpp
@@ -630,7 +630,7 @@ void QXcbWindow::show()
         const QWindow *tp = window()->transientParent();
         if (isTransient(window()) || tp != 0) {
             xcb_window_t transientXcbParent = 0;
-            if (tp)
+            if (tp && tp->handle())
                 transientXcbParent = static_cast<const QXcbWindow *>(tp->handle())->winId();
             // Default to client leader if there is no transient parent, else modal dialogs can
             // be hidden by their parents.