[glangdale]

I would be extremely surprised if we were somehow accidentally using MMX; it's not our intention. It is my belief that we are using only AVX2, which, like the 19-year old SSE/SSE2 extension, has its own registers that are independent of the x87 floating point set.

If, once you review our codebase and verify that we are not inadvertently using a 22-year-old SIMD extension but still have undefined behavior, please write an issue on github.

I'm admiring Rust from a distance at this stage. I am comfortable enough with writing bare intrinsics and slapping a giant #ifdef around stuff.