There is also a predictable relation between the input and output of a compiler w.r.t. the semantics of a programming language. Natural languages are ambiguous leaving room for the implementation to diverge that may not be obvious at first glance.

There are also plenty of things a compiler might not expose that end up being ambiguous. For example, C++ doesn't officially have a restrict keyword, so how can you express the fact that two memory regions never operlap and can be optimized? Unfortunately the reality is that if we had a language capable of truly expressing the programmer's intent we'd end up with a monster