/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */
/*
 *
 *  (C) 2003 by Argonne National Laboratory.
 *      See COPYRIGHT in top-level directory.
 */
#include "mpi.h"
#include <stdio.h>
#include "mpitest.h"

/*
static char MTEST_Descrip[] = "Create a communicator with a graph that contains no processes";
*/

int main(int argc, char *argv[])
{
    int errs = 0;
    int *index = 0, *edges = 0;
    MPI_Comm comm;

    MTest_Init(&argc, &argv);

    /* MPI 2.1, page 246, lines 29-30 make it clear that this is a valid
     * (not erroneous) call that must return MPI_COMM_NULL */
    MPI_Graph_create(MPI_COMM_WORLD, 0, index, edges, 0, &comm);
    if (comm != MPI_COMM_NULL) {
        errs++;
        fprintf(stderr, "Expected MPI_COMM_NULL from empty graph create\n");
    }

    MTest_Finalize(errs);
    return MTestReturnValue(errs);
}