After reading this post the idea of a C-to-C translator that injects bound checking, etc. comes to mind. Such translator could be used by OS distributions to provide safety in the least intrusive way and possibly completely automatically for many C codebases they have in their repositories. Translating into Go or Rust, on the other hand, cannot scale beyond some individual projects, that decide to undertake such efforts. Mainstream C compilers could implement safety features too, but realistically it cannot happen, as it's not something most people care about. So, C-to-C translator might be a best bet with the most impact.

Lifetime inference etc is a hard problem, and if it could be done right now, compilers would just have static checks for all that.

There is a C to UNSAFE Rust transpiler, though: https://github.com/jameysharp/corrode.