Port simgear to Apple silicon
Work around Clang preventing var init in file scope with function call
Fix Clang error about illegal alignas() use
Set up SSE vector flags on Clang only when the architecture is x86
Trivial typo fix namsepace -> namespace
Move includes after the general templates they specialize
Match specialization prototypes to templates in simd.hxx
Remove unused var "g" so that the union is anonymous