[lmm]

Rust has far more enthusiasm from potential contributors than any of those options. Onboarding something is meaningless if it's not going to be used and maintained.

FWIW I would trust anything language-level over applying static analysis tools to C (for an evolving codebase like Linux, having the safety be a first-class part of the codebase is a must) or extracting C from another language (the semantics of C are surprisingly weak, such an extraction can only ever be as good as your model of C which will probably be buggy).