dct-test: give emms a memory clober.

Without this, the compiler in theory could attempt to keep
things in float registers across the emms which would cause
bad things to happen.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

diff --git a/libavcodec/dct-test.c b/libavcodec/dct-test.c
index f85bccb4206379f35174020f23eeda067e51986f..c75202ab759e59610b3e72e49f36b0ba806ab2a8 100644 (file)
--- a/libavcodec/dct-test.c
+++ b/libavcodec/dct-test.c
@@ -204,7 +204,7 @@ static inline void mmx_emms(void)
 {
 #if HAVE_MMX
     if (cpu_flags & AV_CPU_FLAG_MMX)
-        __asm__ volatile ("emms\n\t");
+        __asm__ volatile ("emms\n\t" ::: "memory");
 #endif
 }