message: it was a mistake to redirect stderr using the -o flag, so undo that
diff: @@ -362,7 +362,6 @@ int main(int argc, char **argv) {
  if (!opt_outputfile.empty()) {
  OutFile.open(opt_outputfile);
  std::cout.rdbuf(OutFile.rdbuf());
  - std::cerr.rdbuf(OutFile.rdbuf());
  }
  auto M1 = openInputFile(Context, opt_file1);
  