skip c++ mpi in petsc.h

[Lisandro Dalcin]

MPICH2, at least 1.0.5, has a more specific way to ignore the SEEK_*
issue. What PETSc is currently doing is just completelly skipping the
#include of MPI C++ bindings. In OpenMPI, they try hard to solve this
issue and not just generate an error like MPICH2, however, compilation
time is (about 4x) increased as they have to include <iostream>.

I believe doing

#define MPICH_SKIP_MPICXX
#define OMPI_SKIP_MPICXX
#include <mpi.h>

Should always work and then PETSc follows the same path for both
MPI's. Of course, if users want to use C++ bindings, then they have to
#include <mpi.h> before #include <petsc.h>, but it's up to them to
solve the issues with MPICH2.





On 9/10/07, Barry Smith <bsmith at mcs.anl.gov> wrote:
>
>   Actually it is the MPI standard and C++ namespaces etc that cause
> tis funny problem, MPICH just picked a particular work-around.
> I do not know what work around, if any, OpenMPI used.
>
>    Barry
>
>
> On Mon, 10 Sep 2007, Matthew Knepley wrote:
>
> > Not sure. This only happens because MPICH does funny things with SEEK_SET.
> >
> >   Matt
> >
> > On 9/10/07, Lisandro Dalcin <dalcinl at gmail.com> wrote:
> > > We currently do the following in petsc.h
> > >
> > > #define MPICH_SKIP_MPICXX 1
> > > #include "mpi.h"
> > >
> > > Should do the same for OpenMPI ?
> > >
> > >
> > > --
> > > Lisandro Dalcín
> > > ---------------
> > > Centro Internacional de Métodos Computacionales en Ingeniería (CIMEC)
> > > Instituto de Desarrollo Tecnológico para la Industria Química (INTEC)
> > > Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
> > > PTLC - Güemes 3450, (3000) Santa Fe, Argentina
> > > Tel/Fax: +54-(0)342-451.1594
> > >
> > >
> >
> >
> >


-- 
Lisandro Dalcín
---------------
Centro Internacional de Métodos Computacionales en Ingeniería (CIMEC)
Instituto de Desarrollo Tecnológico para la Industria Química (INTEC)
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
PTLC - Güemes 3450, (3000) Santa Fe, Argentina
Tel/Fax: +54-(0)342-451.1594