From fcf68cfd6956a75d151f8b7b3dbb8e2354d1a4f0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Thomas=20L=C3=BCbking?= <thomas.luebking@gmail.com>
Date: Mon, 14 Feb 2011 21:13:31 +0100
Subject: [PATCH] secure m_highlightedWindows access when triggering explicit
 repaint in highlight effect

forward port of 891a0a2a3272186c2c7a93f7a332e04809e3d4d4
---
 effects/highlightwindow/highlightwindow.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/effects/highlightwindow/highlightwindow.cpp b/effects/highlightwindow/highlightwindow.cpp
index 1e9f15e427..8e78b027ce 100644
--- a/effects/highlightwindow/highlightwindow.cpp
+++ b/effects/highlightwindow/highlightwindow.cpp
@@ -240,7 +240,8 @@ void HighlightWindowEffect::prepareHighlighting()
     foreach (EffectWindow * w, effects->stackingOrder())
     if (!m_windowOpacity.contains(w))    // Just in case we are still finishing from last time
         m_windowOpacity[w] = isInitiallyHidden(w) ? 0.0 : 1.0;
-    m_highlightedWindows.at(0)->addRepaintFull();
+    if (!m_highlightedWindows.isEmpty())
+        m_highlightedWindows.at(0)->addRepaintFull();
 }
 
 void HighlightWindowEffect::finishHighlighting()