If by "no standard" you mean that there is no language specification for rust, then there is no standard. However, a language specification is not sufficient to

If by "no standard" you mean that there is no language specification for rust, then there is no standard. However, a language specification is not sufficient to verify program correctness, nor is it required. A standard may (and the C standard for example does) leave parts of the behavior as "implementation specific" and there's quite a few edge cases - and that's not even talking about "undefined behavior", of which there is plenty. An even in the behavior that is neither implementation specific nor undefined you'll find enough rope to hang yourself (all the beautiful pointers). There's a reason things such as MISRA C exist - effectively a standard on top of a standard. On the other hand, the rust language - while having no formal spec - is fairly well described, in the form of its RFCs and testsuite. We (the ferrocene team) were able to derive a descriptive specification from the existing description fairly easily. So while there is no ISO standard, and no spec that would be sufficient to write a competing implementation, there is a description of what the language behaves like. You can read up on it at https://spec.ferrocene.dev/ https://spec.ferrocene.dev/ As for verification of correct behavior of such a program, you can employ a host of different techniques depending on what your requirements are - down to verification of the produced bytecode by means of blackbox testing or other.