Yeah, it's possible to write a disciplined form of C++ that abides by those rules, but I think it's important that the idiomatic form of error handling in Rust is returning Result types instead of unwinding, the standard library doesn't have coercions that allocate, etc. If you write some Rust code following a Rust tutorial, it would probably be kernel-suitable. That's also largelytrue of C but not of C++.

(And Linus noticed one of the big parts where Rust doesn't live up to this - the idiomatic thing for memory allocation failure is to unwind - and that's a solvable problem.)