There is a C++ standard that everyone writing C++ code follows and newer version are usually compatible with one another regardless of toolchain version. Behavior of the toolchain should not change. Worst case you can use deterministic, reliable tools to automatically detect problematic locations if there really is a behavior change. (compiler warnings/errors for example)

AI code generation is not deterministic and has no guarantee of behavior, thus requires review unless incorrect code is acceptable.

>AI code generation is not deterministic

You don't have to use AI code generation to be what is generating the code or you could require some kind of proof of equivalence to verify the code that was generated.