message: [crispy] FNV: should be better that way.
diff: @@ -30,7 +30,7 @@ class FNV
  /// and returns the applied FNV result.
  constexpr U operator()(U _memory, T _value) const noexcept
  {
  - _memory ^= static_cast<std::common_type_t<T, U>>(_value);
  + _memory ^= static_cast<U>(_value);
  _memory *= prime_;
  return _memory;
  }
  