const correctness and static member variables

Are static member variables exempt from "const" declarations? Because this compiled with gcc 4.0.3:

Code:

---

//in the header
class A
{
  static int i;
  void inc() const  {i++;}
}

//and in the source
int A::i = 0;

---

So is it possible to change class member variables even within a constant function as long as they're declared static?

static variables are not members of the instance. The instance is constant in inc (the this pointer that is passed implicitly) but static members are not accessed through the instance (or the this pointer).

In addition, you can also modify non-static member variables in const member functions if you declare them mutable (but that should be very rarely needed).

That explains it. Thanks.