[Pixman] xmmintrin.h (was [PATCH 2/4] Disable MMX when incompatible clang is being used.)

[Jeremy Huddleston]

>>>>> Newer clangs support the "K" constraint? Fixed in response to its use
>>>>> in pixman? :)
> 
> And to close the loop on this, the fix has landed in clang trunk and will be in 3.1:
> http://lists.cs.uiuc.edu/pipermail/cfe-commits/Week-of-Mon-20120319/055254.html


And the other half of the issue seems to be a bug in pixman (at least that's what I am told):

"""
> FWIW the problem happening here with inlining is that at -O0 the constant isn't being propagated through the inlining and so we have the 'K' constant error that you see.

IMO, the source of this problem is that pixman isn't using clang's xmmintrin.h, which defines _mm_shuffle_pi16 for exactly this reason.  They should fix that.
"""

--Jeremy