Open MPI logo

Open MPI User's Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Open MPI User's mailing list

Subject: Re: [OMPI users] fortran program with integer kind=8 using openmpi
From: George Bosilca (bosilca_at_[hidden])
Date: 2012-07-01 07:38:37


Based on the sizes reported by configure (in the opal_config.h file), we map the Fortran types to C types at runtime. Thus, if there is an identical C type (and this is the case for all integers), all Fortan types will have as a backend the corresponding int type.

Can you send your opal_config.h and config.log please.

  george.

On Jun 30, 2012, at 00:15 , William Au wrote:

> My concern is how do the C side know fortran integer using 8 bytes?
> My valgrind check show something like:
>
> ==8482== Invalid read of size 8
> ==8482== at 0x5F4A50E: ompi_op_base_minloc_2integer (op_base_functions.c:631)
> ==8482== by 0xBF70DD1: ompi_coll_tuned_allreduce_intra_recursivedoubling (op.h:498)
> ==8482== by 0x5F031CB: PMPI_Allreduce (pallreduce.c:105)
> ==8482== by 0x62E2F22: PMPI_ALLREDUCE (pallreduce_f.c:77)
> ==8482== by 0x5C8934: mumps_276_ (mumps_part9.F:4667)
> ==8482== by 0x54D89A: dmumps_ (dmumps_part1.F:157)
> ==8482== by 0x43D358: dmumps_f77_ (dmumps_part3.F:6651)
> ==8482== by 0x41420C: dmumps_c (mumps_c.c:422)
> ==8482== by 0x412CB4: main (my_cExample_client.c:80)
> ==8482== Address 0x7369608 is 0 bytes after a block of size 8 alloc'd
> ==8482== at 0x4A0610C: malloc (vg_replace_malloc.c:195)
> ==8482== by 0xBF709B9: ompi_coll_tuned_allreduce_intra_recursivedoubling (coll_tuned_allreduce.c:158)
> ==8482== by 0x5F031CB: PMPI_Allreduce (pallreduce.c:105)
> ==8482== by 0x62E2F22: PMPI_ALLREDUCE (pallreduce_f.c:77)
> ==8482== by 0x5C8934: mumps_276_ (mumps_part9.F:4667)
> ==8482== by 0x54D89A: dmumps_ (dmumps_part1.F:157)
> ==8482== by 0x43D358: dmumps_f77_ (dmumps_part3.F:6651)
> ==8482== by 0x41420C: dmumps_c (mumps_c.c:422)
> ==8482== by 0x412CB4: main (my_cExample_client.c:80)
>
>
> The fortran side:
>
> INTEGER IN( 2 ), OUT( 2 )
>
> CALL MPI_ALLREDUCE( IN, OUT, 1, MPI_2INTEGER, MPI_MINLOC,
> & COMM, IERR)
>
> The compiler options will take care of IN be INTEGER*8, but will
> it do the same for MPI_2INTEGER in the C side
>
> Thanks.
>
> Regards,
>
> William
>
>
>
> Date: Fri, 29 Jun 2012 07:03:18 -0400
> From: Jeff Squyres <jsquyres_at_[hidden]>
> Subject: Re: [OMPI users] fortran program with integer kind=8 using
> openmpi
> To: <warren_at_[hidden]>, Open MPI Users <users_at_[hidden]>
> Message-ID: <6FFEA644-3F39-4B6E-ADD6-3721F485525F_at_[hidden]>
> Content-Type: text/plain; charset=iso-8859-1
>
> On Jun 28, 2012, at 8:37 PM, David Warren wrote:
>
> > You should not have to recompile openmpi, but you do have to use the correct type. You can check the size of integers in your fortrana nd use MPI_INTEGER4 or MPI_INTEGER8 depending on what you get.
>
> If you configure ompi with -fdefault-integer-8, then OMPI will assume that Fortran integers are always 8 bytes, so be sure to also compile all of your MPI applications the same way. Indeed, you may want to configure OMPI with something like:
>
> ./configure FCFLAGS=-fdefault-integer-8 FFLAGS=-fdefault-integer-8 \
> --with-wrapper-fflags=-fdefault-integer-8 \
> --with-wrapper-fcflags=-fdefault-integer-8
>
> This will add -fdefault-integer-8 to the mpif77 and mpif90 command lines automatically so that you *can't* compile without that flag.
>
> Be aware that 8-byte Fortran integers *should work* in Open MPI, but it is probably not well tested. You may well run into some issues; be sure to let us know if you run into bugs. Sending small test programs that show the problem are usually the best way to help us identify/fix the precise problem.
>
> > in gfortran use
> > integer i
> > if(sizeof(i) .eq. 8) then
> > mpi_int_type=MPI_INTEGER8
> > else
> > mpi_int_type=MPI_INTEGER4
> > endif
>
> I don't think that this should be necessary -- as long as you configured OMPI with the 8-byte-integer setting, then MPI_INTEGER should represent an 8 byte integer.
>
> --
> Jeff Squyres
> jsquyres_at_[hidden]
> For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/
>
> _______________________________________________
> users mailing list
> users_at_[hidden]
> http://www.open-mpi.org/mailman/listinfo.cgi/users