Disable MMX when incompatible clang is being used.

Signed-off-by: Jeremy Huddleston <jeremyhu@apple.com>

diff --git a/configure.ac b/configure.ac
index c3c711c..1ca3c02 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -297,6 +297,15 @@ AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
 #include <mmintrin.h>
 int main () {
     __m64 v = _mm_cvtsi32_si64 (1);
+    __m64 w;
+    int8_t x;
+
+    /* Some versions of clang will choke on K */
+    asm ("pshufw %2, %1, %0\n\t"
+        : "=y" (v)
+        : "y" (w), "K" (x)
+    );
+
     return _mm_cvtsi64_si32 (v);
 }]])], have_mmx_intrinsics=yes)
 CFLAGS=$xserver_save_CFLAGS