[c-cube]

That's plain wrong. If static analysis was as reliable as rust, why would all these C codebases still be full of buffer overflows and memory errors? The borrow checker is, in effect, a static analysis tool... that requires a lot of annotations from the programmer, and blocks compilation otherwise. The equivalent for C would be to annotate all your functions in some formal language and then run, say, frama-C.

About valgrind or sanitizers: they're runtime, so just like tests they can only show the presence of errors, not their absence. Like dynamic type checking.