Access to low level memory such as registers is always explicitly requested with the volatile keyword. All other memory is implementation details. C is far from

Access to low level memory such as registers is always explicitly requested with the volatile keyword. All other memory is implementation details. C is far from being a human readable assembly and has never been, except accidentally. Even the old language spec from 1989 talks about an "abstract machine with the expressions being evaluated as specified by the semantics". One of the first chapters 1.2 Scope makes this very clear and then 2.1.2.3 Program execution clarifies this even further. Other things to note is that the spec doesn't mention variables being ever stored on the stack, instead it's called automatic storage, see "Storage durations of objects", the word stack is not even mentioned once throughout the whole spec. Today with modern CPUs all this is even more important, if you think you are operating on a global memory array you are doing it wrong.