message: improve solver benchmark error output
diff: @@ -94,11 +94,11 @@ DEFINE_bool(overhead, false,
  // input validation
  [[noreturn]] void print_config_error_and_exit()
  {
  - std::cerr
  - << "Input has to be a JSON array of matrix configurations:\n"
  + std::cerr << "Input has to be a JSON array of matrix configurations:\n"
  << " [\n"
  << " { \"filename\": \"my_file.mtx\", \"optimal\": { "
  - "\"spmv\": \"<matrix format>\" }, \"rhs\": \"my_file_rhs.mtx\" },\n"
  + "\"spmv\": \"<matrix format>\" },\n"
  + " \"rhs\": \"my_file_rhs.mtx\" },\n"
  << " { \"filename\": \"my_file2.mtx\", \"optimal\": { "
  "\"spmv\": \"<matrix format>\" } }\n"
  << " ]" << std::endl;
  @@ -386,7 +386,8 @@ int main(int argc, char *argv[])
  std::string format =
  std::string() + " [\n" +
  " { \"filename\": \"my_file.mtx\", \"optimal\": { "
  - "\"spmv\": \"<matrix format>\" }, \"rhs\": \"my_file_rhs.mtx\" },\n" +
  + "\"spmv\": \"<matrix format>\" },\n"
  + " \"rhs\": \"my_file_rhs.mtx\" },\n" +
  " { \"filename\": \"my_file2.mtx\", \"optimal\": { "
  "\"spmv\": \"<matrix format>\" } }\n" +
  " ]\n\n" +
  