Bug 526586 - XULRunner crashes on startup on Windows r=bustage fix and at least agreement on the approach from dbaron

xpcom/base/nsCycleCollector.cpp

@@ -1182,7 +1182,7 @@ Fault(const char *msg, PtrInfo *pi)
 static inline bool
 CheckMainThreadIfFast()
 {
-#ifdef NS_TLS
+#if defined(XP_WIN) || defined(NS_TLS)
     return NS_IsMainThread();
 #else
     return true;

xpcom/base/nscore.h

@@ -466,9 +466,7 @@ typedef PRUint32 nsrefcnt;
 #define XPCOM_GLUE_AVOID_NSPR
 #endif
 
-#if defined(_MSC_VER) && !defined(WINCE)
-#define NS_TLS __declspec(thread)
-#elif defined(HAVE_THREAD_TLS_KEYWORD)
+#if defined(HAVE_THREAD_TLS_KEYWORD)
 #define NS_TLS __thread
 #endif
 

xpcom/glue/nsThreadUtils.cpp

@@ -46,6 +46,10 @@
 # include "nsServiceManagerUtils.h"
 #endif
 
+#ifdef XP_WIN
+#include <windows.h>
+#endif
+
 #ifndef XPCOM_GLUE_AVOID_NSPR
 
 NS_IMPL_THREADSAFE_ISUPPORTS1(nsRunnable, nsIRunnable)
@@ -126,6 +130,13 @@ bool NS_IsMainThread()
     mgr->GetIsMainThread(&result);
   return bool(result);
 }
+#elif defined(XP_WIN)
+extern DWORD gTLSIsMainThreadIndex;
+bool
+NS_IsMainThread()
+{
+  return !!TlsGetValue(gTLSIsMainThreadIndex);
+}
 #elif !defined(NS_TLS)
 bool NS_IsMainThread()
 {

xpcom/glue/nsThreadUtils.h

@@ -98,7 +98,11 @@ NS_GetCurrentThread(nsIThread **result);
 extern NS_COM_GLUE NS_METHOD
 NS_GetMainThread(nsIThread **result);
 
-#if defined(MOZILLA_INTERNAL_API) && defined(NS_TLS)
+#if defined(MOZILLA_INTERNAL_API) && defined(XP_WIN)
+
+NS_COM bool NS_IsMainThread();
+
+#elif defined(MOZILLA_INTERNAL_API) && defined(NS_TLS)
 // This is defined in nsThreadManager.cpp and initialized to `true` for the
 // main thread by nsThreadManager::Init.
 extern NS_TLS bool gTLSIsMainThread;

xpcom/threads/nsThreadManager.cpp

@@ -44,7 +44,10 @@
 #include "nsAutoPtr.h"
 #include "nsAutoLock.h"
 
-#ifdef NS_TLS
+#ifdef XP_WIN
+#include <windows.h>
+DWORD gTLSIsMainThreadIndex = TlsAlloc();
+#elif defined(NS_TLS)
 NS_TLS bool gTLSIsMainThread = false;
 #endif
 
@@ -106,7 +109,9 @@ nsThreadManager::Init()
   // GetIsMainThread calls that occur post-Shutdown.
   mMainThread->GetPRThread(&mMainPRThread);
 
-#ifdef NS_TLS
+#ifdef XP_WIN
+  TlsSetValue(gTLSIsMainThreadIndex, (void*) 1);
+#elif defined(NS_TLS)
   gTLSIsMainThread = true;
 #endif