Progress towards this is always being made, though it's a long road with much still to determine. I encourage anyone interested in this to join the Zulip channel for Rust's unsafe code guidelines working group: https://rust-lang.zulipchat.com/#narrow/stream/t-lang.2Fwg-u...

Some recent developments: https://gankra.github.io/blah/tower-of-weakenings/