diff --git a/libs/libvorbis-1.3.5/lib/os.h b/libs/libvorbis-1.3.5/lib/os.h
index 8bc3e5fe..624b0d0e 100644
--- a/libs/libvorbis-1.3.5/lib/os.h
+++ b/libs/libvorbis-1.3.5/lib/os.h
@@ -148,7 +148,7 @@ static __inline void vorbis_fpu_restore(vorbis_fpu_control fpu){
 
 /* Optimized code path for x86_64 builds. Uses SSE2 intrinsics. This can be
    done safely because all x86_64 CPUs supports SSE2. */
-#if (defined(_MSC_VER) && defined(_WIN64)) || (defined(__GNUC__) && defined (__x86_64__))
+#if (defined(_MSC_VER) && defined(_M_AMD64)) || (defined(__GNUC__) && defined (__x86_64__))
 #  define VORBIS_FPU_CONTROL
 
 typedef ogg_int16_t vorbis_fpu_control;