Question

This is a theoretical question.

I wonder how certain constructions in C are performed internally without references. For example:

struct Foo { int a; };
int main() {
  struct Foo foo;
  foo.a = 10;
  return 0;
}

What is the type of foo.a? It’s definitely not a pointer, because we assign 10 as a value, not address. But it’s not a value type as well, because it changes data of foo. In C++ I would just say that it’s a reference, but in C?

Answer 1

It is an int lvalue. Same as if you had int bar, and bar = 10 changes the data of bar. Same applies to any element within an array. Basically anything you can take the address of is an lvalue.

Lvalue status is independent of type.