Newsgroups: comp.sys.sgi.bugs,comp.parallel.mpi
From: Anthony Chan <tonychan@rainbow.uchicago.edu>
Subject: Re: Bugs of Array Services 3.1 on Origin2000
Organization: University of Chicago -- Academic Computing Services
Date: Thu, 9 Jul 1998 17:25:38 GMT
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Message-ID: <35A4FD11.E6F17D37@rainbow.uchicago.edu>

Raja Daoud wrote:

> Anthony Chan  <tonychan@rainbow.uchicago.edu> wrote:
>
> >      nranks   = 1
> >      ranks(1) = myid
>
> >      call MPI_Group_incl( group_in, nranks, ranks, group_out, ierr )
>
> >      call MPI_Comm_create( comm_in, group_out, comm_out, ierr )
>
> This code is erroneous when #procs > 1: group_out is different in each
> process, that's not allowed when calling MPI_Comm_create().
>
> --Raja
>
> -=-
> Raja Daoud                              Hewlett-Packard Co.
> raja@rsn.hp.com                         http://www.hp.com/go/mpi

  This is a SPMD program, group_out should be different for each
process.  The whole idea is to create one group for each process.
I checked the return status from MPI_Comm_create(), it is OK.
So could you explain why it is NOT allowed ?

Thanks

A.Chan