[Bug c++/95888] [9/10/11 Regression] Regression in 9.3. GCC freezes when compiling code using boost::poly_collection::segment

[mpolacek at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95888

--- Comment #5 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Simplified test:

template <typename T> class A {
  A(int, int);
  template <typename> friend class A;
  friend T;
};

template<typename U> struct B {
  template<typename T> struct C {
    A<B> begin() { return {1, 0}; }
  };
  template<typename T, int *P = nullptr>
  C<T> fn();
};

int
main ()
{
  B<int> b;
  b.fn<int>().begin();
}