typename7.c

this is a gcc file, you can download it and learn its usetility, for further detail please look at t

// Test for implicit typename
// Build don't link:
// Special g++ Options:

template <class T>
struct A {
protected:
  typedef struct B { } B;
};

template <class T>
struct C { };

template <class T>
struct D : public A <C <T> > {
  void f ()
    {
      B* new_entries = (B *) 0;  // WARNING - implicit typename
    }
};