2fe2975391
never consider unsafe blocks unused if they would be required with deny(unsafe_op_in_unsafe_fn) Judging from https://github.com/rust-lang/rust/issues/71668#issuecomment-1200317370 the consensus nowadays seems to be that we should never consider an unsafe block unused if it was required with `deny(unsafe_op_in_unsafe_fn)`, no matter whether that lint is actually enabled or not. So let's adjust rustc accordingly. The first commit does the change, the 2nd does some cleanup.
For more information about how rustc works, see the rustc dev guide.