Unambiguous class members

The compiler can unambiguously find static members, nested types, and enumerators defined in a base class A regardless of the number of subobjects of type A an object has. The following example demonstrates this:

struct A {
   int x;
   static int s;
   typedef A* Pointer_A;
   enum { e };
};

int A::s;

struct B: A { };

struct C: A { };

struct D: B, C {
   void f() {
      s = 1;
      Pointer_A pa;
      int i = e;
//      x = 1;
   }
};

int main() {
   D i;
   i.f();
}

The compiler allows the assignment s = 1, the declaration Pointer_A pa, and the statement int i = e. There is only one static variable s, only one typedef Pointer_A, and only one enumerator e. The compiler would not allow the assignment x = 1 because x can be reached either from class B or class C.