From 0f613007cd43545eda40825bd74ada3e6e5f36f6 Mon Sep 17 00:00:00 2001
From: Jeremy Huddleston <jeremyhu@freedesktop.org>
Date: Wed, 5 Aug 2009 17:43:29 -0700
Subject: [PATCH] CheckWindowOptionalNeed: Ensure w->optional is set to avoid
 SEGFAULT

If CheckWindowOptionalNeed is called consecutively (and the first removes optional), then
we will SEGFAULT.  This can happen in XQuartz because ReparentWindow will call
pScreen->ReparentWindow which can DeleteProperty which will CheckWindowOptionalNeed... then
ReparentWindow will call it again later indiscriminantly.
(cherry picked from commit b608c864ccc59628bd33c033393121b61580460e)
---
 dix/window.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dix/window.c b/dix/window.c
index 1a645f61f..9663578f7 100644
--- a/dix/window.c
+++ b/dix/window.c
@@ -3386,7 +3386,7 @@ CheckWindowOptionalNeed (WindowPtr w)
     WindowOptPtr optional;
     WindowOptPtr parentOptional;
 
-    if (!w->parent)
+    if (!w->parent || !w->optional)
 	return;
     optional = w->optional;
     if (optional->dontPropagateMask != DontPropagateMasks[w->dontPropagate])