[HarfBuzz] harfbuzz: Branch 'master'

[Behdad Esfahbod]

 src/hb-atomic-private.hh |   12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

New commits:
commit fbb2847f541389f40718af71c4945024ae177ab2
Author: Behdad Esfahbod <behdad at behdad.org>
Date:   Wed Feb 5 08:22:06 2014 -0500

    Improve MemoryBarrier() implementation
    
    See thread "[HarfBuzz] compilation error of 0.9.26 with MinGW"
    started by Werner.

diff --git a/src/hb-atomic-private.hh b/src/hb-atomic-private.hh
index b5d6485..1c4e120 100644
--- a/src/hb-atomic-private.hh
+++ b/src/hb-atomic-private.hh
@@ -47,18 +47,22 @@
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 
-#if defined(__MINGW32__) && !defined(MemoryBarrier)
+/* MinGW has a convoluted history of supporting MemoryBarrier
+ * properly.  As such, define a function to wrap the whole
+ * thing. */
 static inline void _HBMemoryBarrier (void) {
+#if !defined(MemoryBarrier)
   long dummy = 0;
   InterlockedExchange (&dummy, 1);
-}
-# define MemoryBarrier _HBMemoryBarrier
+#else
+  MemoryBarrier ();
 #endif
+}
 
 typedef LONG hb_atomic_int_t;
 #define hb_atomic_int_add(AI, V)	InterlockedExchangeAdd (&(AI), (V))
 
-#define hb_atomic_ptr_get(P)		(MemoryBarrier (), (void *) *(P))
+#define hb_atomic_ptr_get(P)		(_HBMemoryBarrier (), (void *) *(P))
 #define hb_atomic_ptr_cmpexch(P,O,N)	(InterlockedCompareExchangePointer ((void **) (P), (void *) (N), (void *) (O)) == (void *) (O))