Does it work in mock on non-x86? x86intrin.h is x86-specific header
and won't
be present on other arches, but it looks like it's included unconditionally.
Weill not exactly.
gcc-trunk/trunk$ find ./ -name x86intrin.h
./gcc/config/i386/x86intrin.h
./gcc/config/rs6000/x86intrin.h
PPC has functionally equivalent x86 intrinsic headers for MMX through SSE4,?
./gcc/config/rs6000/htmintrin.h
./gcc/config/rs6000/mmintrin.h
./gcc/config/rs6000/pmmintrin.h
./gcc/config/rs6000/xmmintrin.h
./gcc/config/rs6000/bmi2intrin.h
./gcc/config/rs6000/smmintrin.h
./gcc/config/rs6000/emmintrin.h
./gcc/config/rs6000/htmxlintrin.h
./gcc/config/rs6000/tmmintrin.h
./gcc/config/rs6000/bmiintrin.h
./gcc/config/rs6000/x86intrin.h
So it may work there, but is unlikely to work on any other platform.