From a6774396bdd973616acf9ae09626b697b9dfa6c0 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Mon, 2 Mar 2009 10:51:41 +0000
Subject: [PATCH] From Mathias Froehlich, "An other one: The TLS Varialbe is
 accessed before it is initialized. Attached is a change to rev 9791."

Merged from svn/trunk using:

   svn merge -r 9831:9832 http://www.openscenegraph.org/svn/osg/OpenSceneGraph/trunk/src/OpenThreads/win32
---
 src/OpenThreads/win32/Win32Thread.cpp          |  5 +++--
 src/OpenThreads/win32/Win32ThreadPrivateData.h | 12 ++++++++++--
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/OpenThreads/win32/Win32Thread.cpp b/src/OpenThreads/win32/Win32Thread.cpp
index afa8dd70a..7e17f8362 100644
--- a/src/OpenThreads/win32/Win32Thread.cpp
+++ b/src/OpenThreads/win32/Win32Thread.cpp
@@ -98,7 +98,7 @@ namespace OpenThreads {
 
             if (thread->_prvData==0) return 0;
 
-            TlsSetValue(Win32ThreadPrivateData::TLS.ID ,data);
+            TlsSetValue(Win32ThreadPrivateData::TLS.getId(), data);
             //---------------------------------------------------------------------
             // Set the proper scheduling priorities
             //
@@ -127,6 +127,7 @@ namespace OpenThreads {
                 // abnormal termination but must be caught in win32 anyway
             }
 
+            TlsSetValue(Win32ThreadPrivateData::TLS.getId(), 0);
             pd->isRunning = false;
 
             return 0;
@@ -207,7 +208,7 @@ namespace OpenThreads {
 
 Thread* Thread::CurrentThread()
 {
-    return (Thread* )TlsGetValue(Win32ThreadPrivateData::TLS.ID);
+    return (Thread* )TlsGetValue(Win32ThreadPrivateData::TLS.getId());
 };
 
 //----------------------------------------------------------------------------
diff --git a/src/OpenThreads/win32/Win32ThreadPrivateData.h b/src/OpenThreads/win32/Win32ThreadPrivateData.h
index e26b65b19..451c1af42 100644
--- a/src/OpenThreads/win32/Win32ThreadPrivateData.h
+++ b/src/OpenThreads/win32/Win32ThreadPrivateData.h
@@ -69,12 +69,20 @@ public:
     HandleHolder cancelEvent;
 
     struct TlsHolder{ // thread local storage slot
-        DWORD ID;
-        TlsHolder(): ID(TlsAlloc()){
+        DWORD getId()
+        {
+            static bool initialized = false;
+            if (!initialized) {
+                ID = TlsAlloc();
+                initialized = true;
+            }
+            return ID;
         }
         ~TlsHolder(){
             TlsFree(ID);
         }
+    private:
+        DWORD ID;
     };
 
     static TlsHolder TLS;