For some unknow reason some intrinsics fail to get inlined. Using extern inline results in a linker error. Change it to static inline, so that there is a static implementation in case it doesn't get inlined
These headers come with the MS compiler. Some of them are standard, like emmintrin.h, others are MS specific like crtdefs.h
This separation will allow using MS CRT headers. Eventually it can allow compiling with the compilers' runtime headers.
Ahmed ARIF