message: Remove extra semicolon to quiet -Wpedantic
diff: @@ -40,7 +40,7 @@ template <class> class intrusive_ptr;
  template <class> class optional;
  template <class> class param;
  template <class> class span;
  -template <class> class stream;;
  +template <class> class stream;
  template <class> class stream_sink;
  template <class> class stream_source;
  template <class> class trivial_match_case;
  