From f67a9905ff310b124f91f4d232b785553eafbd2b Mon Sep 17 00:00:00 2001
From: Behdad Esfahbod <behdad@behdad.org>
Date: Thu, 7 Mar 2013 20:14:08 -0500
Subject: [PATCH] [win32] Remove MemoryBarrier() fallback implementation

I added these because the older mingw32 toolchain didn't have
MemoryBarrier().  The newer mingw-w64 toolchain however has.
As reported by John Emmas this was causing build failure with
MSVC because of inline issues.  But that reminded me that we
may be taking this path even if the system implements
MemoryBarrier as a function, which is a waste.  So, just remove
it.
---
 glib/gatomic.c | 20 ++++----------------
 1 file changed, 4 insertions(+), 16 deletions(-)

diff --git a/glib/gatomic.c b/glib/gatomic.c
index 461a8e6b7..5cba767ad 100644
--- a/glib/gatomic.c
+++ b/glib/gatomic.c
@@ -523,25 +523,13 @@ _gInterlockedXor (volatile guint *atomic,
 #define InterlockedXor(a,b) _gInterlockedXor(a,b)
 #endif
 
-/* mingw32 does not have MemoryBarrier.
- * MemoryBarrier may be defined as a macro or a function.
- * Just make a failsafe version for ourselves. */
-#ifdef MemoryBarrier
-#define _GMemoryBarrier MemoryBarrier
-#else
-static inline void _GMemoryBarrier (void) {
-  long dummy = 0;
-  InterlockedExchange (&dummy, 1);
-}
-#endif
-
 /*
  * http://msdn.microsoft.com/en-us/library/ms684122(v=vs.85).aspx
  */
 gint
 (g_atomic_int_get) (const volatile gint *atomic)
 {
-  _GMemoryBarrier ();
+  MemoryBarrier ();
   return *atomic;
 }
 
@@ -550,7 +538,7 @@ void
                     gint           newval)
 {
   *atomic = newval;
-  _GMemoryBarrier ();
+  MemoryBarrier ();
 }
 
 void
@@ -607,7 +595,7 @@ gpointer
 {
   const volatile gpointer *ptr = atomic;
 
-  _GMemoryBarrier ();
+  MemoryBarrier ();
   return *ptr;
 }
 
@@ -618,7 +606,7 @@ void
   volatile gpointer *ptr = atomic;
 
   *ptr = newval;
-  _GMemoryBarrier ();
+  MemoryBarrier ();
 }
 
 gboolean