To what extent is it acceptable to think of C++ pointers as memory addresses?

Question

When you learn C++, or at least when I learned it through C++ Primer, pointers were termed the "memory addresses" of the elements they point to. I'm wondering to what extent this is true.

For example, do two elements *p1 and *p2 have the property p2 = p1 + 1 or p1 = p2 + 1 if and only if they are adjacent in physical memory?

question from:https://stackoverflow.com/questions/34512747/to-what-extent-is-it-acceptable-to-think-of-c-pointers-as-memory-addresses

Answer 1

You should think of pointers as being addresses of virtual memory: modern consumer operating systems and runtime environments place at least one layer of abstraction between physical memory and what you see as a pointer value.

As for your final statement, you cannot make that assumption, even in a virtual memory address space. Pointer arithmetic is only valid within blocks of contiguous memory such as arrays. And whilst it is permissible (in both C and C++) to assign a pointer to one point past an array (or scalar), the behaviour on deferencing such a pointer is undefined. Hypothesising about adjacency in physical memory in the context of C and C++ is pointless.