> rust: rigorous memory safety
> circle : unsafe printf
Comeon people, if you allow unsafety, you cannot call your language safe. There are safe system languages, but don't lie and call unsafe languages safe. Partial safety is not full safety.
> circle : unsafe printf
Comeon people, if you allow unsafety, you cannot call your language safe. There are safe system languages, but don't lie and call unsafe languages safe. Partial safety is not full safety.
> rust: unsafe { println!("{}", *r1); }
Comeon people, if you allow unsafety, you cannot call your language safe. There are safe system languages, but don't lie and call unsafe languages safe. Partial safety is not full safety.
So, this only does anything interesting if r1 was a raw pointer so that dereferencing it would be prohibited without the unsafe block. If it's just a reference or some smart pointer type then that's fine anyway.
Unsafe in Rust means "soundness cannot be statically verified, the language will insert runtime checks for you and perform a clearly defined action (panic) if they are violated".
Much ink has been spilled about "unsafe" in Rust being unfortunately named.
Right.
But as sibling points out, the rest of your sentence is incorrect. The language mostly does not insert additional, runtime checks and you are allowed to create UB-level bad behavior in unsafe blocks.
> It is the programmer's responsibility when writing unsafe code to ensure that any safe code interacting with the unsafe code cannot trigger these behaviors.
https://doc.rust-lang.org/reference/behavior-considered-unde...
And they transverse
> However, violations of these constraints generally will just transitively lead to one of the above problems.