message: Fix static_cast to std::size_t instead of int
diff: @@ -28,7 +28,7 @@ int& PopulationTable::operator[](Role role)
  int PopulationTable::operator[](Role role) const
  {
  - return table[static_cast<int>(role)];
  + return table[static_cast<std::size_t>(role)];
  }
  