That was careless of me. Thanks for pointing it out. Declaring "status", "ierr" and putting "implicit none" solved the problem.
Thanks again. 2013/2/19 Jeff Squyres (jsquyres) <jsquy...@cisco.com> > +1. The problem is that you didn't declare status or ierr. Since you > didn't declare status, you're buffer overflowing, and random Bad Things > happen from there. > > You should *always* "implicit none" to catch these kinds of errors. > > > On Feb 18, 2013, at 2:02 PM, Gus Correa <g...@ldeo.columbia.edu> wrote: > > > Hi Pradeep > > > > For what it is worth, in the MPI Fortran bindings/calls the > > datatype to use is "MPI_INTEGER", not "mpi_int" (which you used; > > MPI_INT is in the MPI C bindings): > > > > http://linux.die.net/man/3/mpi_integer > > > > Also, just to prevent variables to inadvertently come with > > the wrong type, you could add: > > > > implicit none > > > > to the top of your code. > > You already have a non-declared "ierr" in "call mpi_send". > > (You declared "ierror" as an integer, but not "ierr".) > > Although this one may not cause any harm; > > names starting with "i" are integers by default, in old Fortran. > > > > I hope this helps, > > Gus Correa > > > > > > On 02/18/2013 01:26 PM, jody wrote: > >> Hi Pradeep > >> > >> I am not sure if this is the reason, but usually it is a bad idea to > >> force an order of receives (such as you do in your receive loop - > >> first from sender 1 then from sender 2 then from sender 3) > >> Unless you implement it so, there is no guarantee the sends are > >> performed in this order. B > >> > >> It is better if you accept messages from all senders (MPI_ANY_SOURCE) > >> instead of particular ranks and then check where the > >> message came from by examining the status fields > >> (http://www.mpi-forum.org/docs/mpi22-report/node47.htm) > >> > >> Hope this helps > >> Jody > >> > >> > >> On Mon, Feb 18, 2013 at 5:06 PM, Pradeep Jha > >> <prad...@ccs.engg.nagoya-u.ac.jp> wrote: > >>> I have attached a sample of the MPI program I am trying to write. When > I run > >>> this program using "mpirun -np 4 a.out", my output is: > >>> > >>> Sender: 1 > >>> Data received from 1 > >>> Sender: 2 > >>> Data received from 1 > >>> Sender: 2 > >>> > >>> And the run hangs there. I dont understand why does the "sender" > variable > >>> change its value after MPI_recv? Any ideas? > >>> > >>> Thank you, > >>> > >>> Pradeep > >>> > >>> > >>> program mpi_test > >>> > >>> include 'mpif.h' > >>> > >>> !----------------( Initialize variables )-------------------- > >>> integer, dimension(3) :: recv, send > >>> > >>> integer :: sender, np, rank, ierror > >>> > >>> call mpi_init( ierror ) > >>> call mpi_comm_rank( mpi_comm_world, rank, ierror ) > >>> call mpi_comm_size( mpi_comm_world, np, ierror ) > >>> > >>> !----------------( Main program )-------------------- > >>> > >>> ! receive the data from the other processors > >>> if (rank.eq.0) then > >>> do sender = 1, np-1 > >>> print *, "Sender: ", sender > >>> call mpi_recv(recv, 3, mpi_int, sender, 1, > >>> & mpi_comm_world, status, ierror) > >>> print *, "Data received from ",sender > >>> end do > >>> end if > >>> > >>> ! send the data to the main processor > >>> if (rank.ne.0) then > >>> send(1) = 3 > >>> send(2) = 4 > >>> send(3) = 4 > >>> call mpi_send(send, 3, mpi_int, 0, 1, mpi_comm_world, ierr) > >>> end if > >>> > >>> > >>> !----------------( clean up )-------------------- > >>> call mpi_finalize(ierror) > >>> > >>> return > >>> end program mpi_test` > >>> > >>> > >>> _______________________________________________ > >>> users mailing list > >>> us...@open-mpi.org > >>> http://www.open-mpi.org/mailman/listinfo.cgi/users > >> _______________________________________________ > >> users mailing list > >> us...@open-mpi.org > >> http://www.open-mpi.org/mailman/listinfo.cgi/users > > > > _______________________________________________ > > users mailing list > > us...@open-mpi.org > > http://www.open-mpi.org/mailman/listinfo.cgi/users > > > -- > Jeff Squyres > jsquy...@cisco.com > For corporate legal information go to: > http://www.cisco.com/web/about/doing_business/legal/cri/ > > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users >
