Bug#563705: MPI implementations in squeeze

[Lucas Nussbaum]

On 25/02/10 at 14:22 -0500, Adam C Powell IV wrote:
> On Thu, 2010-02-25 at 18:10 +0100, Lucas Nussbaum wrote:
> > > > There is not much progress so far with respect to changing mpi-defaults
> > > > to use MPICH2 instead of LAM on the architectures where Open MPI is not
> > > > available yet. This needs a round of binNMUs. Marc Brockschmidt said he
> > > > will look at the request to debian-release in the next few days, so this
> > > > might resolve soon as well.
> > > 
> > > Something to consider: this will break a lot of packages which use
> > > FORTRAN until 563705 is fixed, and then that will require mods to
> > > packages.
> > 
> > I understand that bug as:
> > if mpich2 or openmpi don't do the right thing when calling
> > mpif77/mpif90, then symlinks are needed.
> > 
> > Is there a proof that either of them doesn't do the right thing?
> > Wouldn't it be more appropriate to fix them to do the right thing?
> > 
> > (Those are honest questions -- I don't know anything about fortran)
> 
> As discussed before (including in the bug), when there are mixed FORTRAN
> and C++ symbols, it's not clear whether to use mpif77/90 or mpic++.
> 
> Also, it's a big convenience: a lot of packages make multiple
> executables and/or libraries, some of which use MPI and some don't.
> Pointing them to -lmpi -lmpi++ -lmpif77 for the MPI execs/lib
> directories seems easier than telling them to use mpicc and friends for
> some targets and gcc for others.

I'm not sure I buy that, since mpicc & friends also hide include paths,
which are not handled with alternatives currently. It sounds more like a
way to break packages by getting them linked with the wrong version of
MPI.
Do you know of packages doing that already?

> And we have libmpi.so and libmpi++.so symlinks, why not libmpif77.so? :)

Well, maybe it might be a better idea to drop those links ;)
-- 
| Lucas Nussbaum
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