[Pixman] [PATCH 2/4] Disable MMX when incompatible clang is being used.

[Jeremy Huddleston]

On Mar 8, 2012, at 09:51, Matt Turner wrote:

> On Thu, Mar 8, 2012 at 5:41 PM, Jeremy Huddleston <jeremyhu at apple.com> wrote:
>> Signed-off-by: Jeremy Huddleston <jeremyhu at apple.com>
>> ---
>>  configure.ac |    9 +++++++++
>>  1 files changed, 9 insertions(+), 0 deletions(-)
>> 
>> diff --git a/configure.ac b/configure.ac
>> index c3c711c..1ca3c02 100644
>> --- 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
>> --
>> 1.7.9
> 
> Newer clangs support the "K" constraint? Fixed in response to its use
> in pixman? :)

Unfortunately, I'm just being optimistic at this point.