template<typename t> class C1 {
  template<typename X> struct rebind {
    typedef C1<X> other;
  };
};

template<typename> class C2;

template<> class C2<void> {
  template<typename X> struct rebind {
    typedef C2<X> other;
  };
};

template<typename t> class C2: public C1<t>
{
  template<typename X> struct rebind {
    typedef C2<X> other;
  };
};

C2<int> blowup;