friend9.c

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

// Build don't link:

// Copyright (C) 2000 Free Software Foundation, Inc.
// Contributed by Nathan Sidwell 24 Nov 2000 <[e-mail]>

// Bug 853: We reported the wrong line no for a friend access violation

class F
{
  class Internal;   // ERROR - is private
};

class C
{
  friend class F::Internal; // ERROR - in this context
  public:
  typedef enum { A, B } e;

  C ();
  ~C();

  void m();
};