Yes, so fix the C standard... But the compiler guys won't let the anyone fix it, because optimizations. So either A) the optimizations using UB are important,

Yes, so fix the C standard... But the compiler guys won't let the anyone fix it, because optimizations. So either A) the optimizations using UB are important, and therefore C is/will-always-be faster than Rust which doesn't have them. Or B) the optimizations using UB are not important and the compiler writers for gcc and clang are wrong. You pick. And of course some insane people advocate for adding undefined behavior to Rust in the name of optimizations. Gross.