> AFAIK, you still have to be very careful since data races based on data dependencies can never be excluded in general, that is theoretically not possible.

Well, you could always require the programmer to supply a proof that the program is gonna be fine, before you compile anything.

(That means your programming language won't be Turing complete, but you can still code up anything you want in practice. Including Turing machines.)

The likes of Agda and Coq work in this way.