Rust doesn't have a volatile memcpy yet, bitfield ergonomics are poor, global variables require thread safety even when targeting a single core device, the memo

Rust doesn't have a volatile memcpy yet, bitfield ergonomics are poor, global variables require thread safety even when targeting a single core device, the memory model isn't finished, and upholding the rules the compiler expects you to respect in unsafe code with regard to aliasing is difficult to wrap your head around (pointer provenance, even the author of tokio got it wrong).