[viraptor]

It's a weird claim. See https://doc.rust-lang.org/book/ch19-01-unsafe-rust.html

> It’s important to understand that unsafe doesn’t turn off the borrow checker or disable any other of Rust’s safety checks: if you use a reference in unsafe code, it will still be checked. The unsafe keyword only gives you access to these five features that are then not checked by the compiler for memory safety.

Fully defined rust or not, unsafe code blocks definitely do not have fewer guarantees than C.