> they still turn it into SIMD or do other very drastic rewrites to it that are hard to reason about Maybe it's just me, but I haven't seen this being a major

> they still turn it into SIMD or do other very drastic rewrites to it that are hard to reason about Maybe it's just me, but I haven't seen this being a major problem in C. Most optimizations are local and fairly easy to reason about. C++ is a whole different story.