1. Safe Rust has no undefined behavior, by design.
2. The poster’s job is to work on defining unsafe Rust, where UB is still a thing. It has to be, to some degree, as that’s the entire point.
3. Miri, references in the post, is an interpreter for the Rust abstract machine (or will be, once we’re done defining it) and gives warnings for many kinds of UB already. The hope is that it will be able to do so for all of it in the future. Doing so means defining what “all of it” means, and that’s still in progress.
2. The poster’s job is to work on defining unsafe Rust, where UB is still a thing. It has to be, to some degree, as that’s the entire point.
3. Miri, references in the post, is an interpreter for the Rust abstract machine (or will be, once we’re done defining it) and gives warnings for many kinds of UB already. The hope is that it will be able to do so for all of it in the future. Doing so means defining what “all of it” means, and that’s still in progress.