text: #include <mpi.h>
  #include <stddef.h>
  #include <stdio.h>
  /*
   * MPI communicator for Allgather is NULL. line 17
   *
   */
  int main(int argc, char *argv[]) {
    int myRank, numProcs;
  
    int local_sum = 4;
    int global_sum[4];
  
    MPI_Init(&argc, &argv);
    MPI_Comm_size(MPI_COMM_WORLD, &numProcs);
    MPI_Comm_rank(MPI_COMM_WORLD, &myRank);
  
    MPI_Comm null_comm = NULL;
    MPI_Allgather(&local_sum, 1, MPI_INT, global_sum, 1, MPI_INT, null_comm);
  
    if (myRank == 0) {
      printf("Result: %d", global_sum[0]);
    }
  
    MPI_Finalize();
  
    return 0;
  }
  