// { dg-do compile { target c++11 } }
// { dg-options "-fconcepts" }
template <typename T> struct A
{
  struct B;
};
struct C
{
  template<typename T> friend struct A<T>::B;
};
// { dg-do compile { target c++11 } }
// { dg-options "-fconcepts" }
template <typename T> struct A
{
  struct B;
};
struct C
{
  template<typename T> friend struct A<T>::B;
};