From c832df0783e2926dab76eb5bc9d7c5d583bb9cd7 Mon Sep 17 00:00:00 2001
From: Kai Ludwig <kludwig@talentraspel.de>
Date: Sat, 24 May 2014 21:22:34 +0200
Subject: [PATCH] added missing locking against crashing in
 Overlays::~Overlays()

---
 interface/src/ui/overlays/Overlays.cpp | 28 +++++++++++++++++---------
 1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/interface/src/ui/overlays/Overlays.cpp b/interface/src/ui/overlays/Overlays.cpp
index da7b05ead7..6c6c314be4 100644
--- a/interface/src/ui/overlays/Overlays.cpp
+++ b/interface/src/ui/overlays/Overlays.cpp
@@ -22,16 +22,26 @@ Overlays::Overlays() : _nextOverlayID(1) {
 }
 
 Overlays::~Overlays() {
-    QMap<unsigned int, Overlay*>::iterator it;
-    for (it = _overlays2D.begin(); it != _overlays2D.end(); ++it) {
-        delete _overlays2D.take(it.key());
-    }
-    for (it = _overlays3D.begin(); it != _overlays3D.end(); ++it) {
-        delete _overlays3D.take(it.key());
-    }
-    while (!_overlaysToDelete.isEmpty()) {
-        delete _overlaysToDelete.takeLast();
+    
+    {
+        QWriteLocker lock(&_lock);
+        foreach(Overlay* thisOverlay, _overlays2D) {
+            delete thisOverlay;
+        }
+        _overlays2D.clear();
+        foreach(Overlay* thisOverlay, _overlays3D) {
+            delete thisOverlay;
+        }
+        _overlays3D.clear();
+	}
+    
+    if (!_overlaysToDelete.isEmpty()) {
+        QWriteLocker lock(&_deleteLock);
+        do {
+            delete _overlaysToDelete.takeLast();
+        } while (!_overlaysToDelete.isEmpty());
     }
+    
 }
 
 void Overlays::init(QGLWidget* parent) {