[FFmpeg-cvslog] w32pthreads: fix mingw build on x86 with -msse2 or higher

[Hendrik Leppkes]

ffmpeg | branch: master | Hendrik Leppkes <h.leppkes at gmail.com> | Wed Oct 14 23:18:17 2015 +0200| [68e00ad66d13c57d9eb3a3862b44ab3fb030e19f] | committer: Luca Barbato

w32pthreads: fix mingw build on x86 with -msse2 or higher

When SSE2 or higher compiler optimizations are used, mingw uses
the _mm_mfence intrinsic for MemoryBarrier, however it doesn't include
the appropriate headers automatically.

Signed-off-by: Luca Barbato <lu_zero at gentoo.org>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=68e00ad66d13c57d9eb3a3862b44ab3fb030e19f
---

 compat/w32pthreads.h |    5 +++++
 1 file changed, 5 insertions(+)

diff --git a/compat/w32pthreads.h b/compat/w32pthreads.h
index ac9a814..3bc69b3 100644
--- a/compat/w32pthreads.h
+++ b/compat/w32pthreads.h
@@ -39,6 +39,11 @@
 #include <windows.h>
 #include <process.h>
 
+/* MinGW requires the intrinsics header for the pthread_once fallback code */
+#if _WIN32_WINNT < 0x0600 && defined(__MINGW32__)
+#include <intrin.h>
+#endif
+
 #include "libavutil/attributes.h"
 #include "libavutil/internal.h"
 #include "libavutil/mem.h"