message: don't cast 0 to `const char`. it makes gcc-trunk unhappy.
diff: @@ -81,7 +81,8 @@ namespace ranges
  meta::_t<std::remove_cv<Char>>>
  operator()(Char *sz) const volatile
  {
  - return ranges::view::delimit(sz, Char(0));
  + using ch_t = meta::_t<std::remove_cv<Char>>;
  + return ranges::view::delimit(sz, ch_t(0));
  }
  };
  