text: //  Copyright John Maddock 2020.
  //  Use, modification and distribution are subject to the
  //  Boost Software License, Version 1.0. (See accompanying file
  //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  
  #ifndef __GNUC__
  #error "compiler is not GCC"
  #endif
  
  int main()
  {
     return 0;
  }
  