>Rust claims to be faster than C and safer than C at the same time. That's not possible.

Of course it's possible. Say you would fork gcc (or clang) and teach it a few extensions for the C type system that allow some more safety checks at compile time (for example something similar to Rusts borrow checker). Since those checks don't change the generated code, you now have a language that's safer than C, but equally fast. Now you add some language primitives that make it easier for the compiler to understand the intend of the programmer, making it easier to optimize the code (there are already plenty of opportunities used by C extensions, like signaling that some if branch is unlikely to be taken. More opportunities exist if you modify the language more heavily). Now you have a language that's both safer and faster than C.

I don't want to make any claims about Rust performance in practice, I haven't run enough benchmarks for that. But it's perfectly possible that the statement could be true.