From owner-sc22wg5@open-std.org  Wed Dec 17 20:24:33 2008
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From: Aleksandar Donev <donev1@llnl.gov>
Organization: LLNL
To: mpi3-fortran@lists.mpi-forum.org
Subject: Re: [MPI3 Fortran] Please tell me I'm wrong
Date: Wed, 17 Dec 2008 11:24:29 -0800
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Cc: Craig Rasmussen <crasmussen@lanl.gov>, WG5 <sc22wg5@open-std.org>
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Craig,

You should read last-week's WG5 messages concerning the Interop TR=20
(especially mine :-). Reinhold Bader already identified this as a=20
problem. The cause of it is the *generic* interface for MPI_Recv.

If you declared the non-generic interface:

subroutine MPI_Recv(buf, count, datatype, source, tag, comm,
   status, err) real, dimension(*), intent(out) =A0:: buf

then you could do

 real :: message(:,:)
  call MPI_Recv(message, 2, MPI_INTEGER, 1, 1, MPI_COMM_WORLD,=20
MPI_STATUS_IGNORE)

and it would work as expected. If "message" is not contiguous a copy=20
in/out would occur.

There is no way to have a generic interface and use "sequence=20
association" argument passing, which is what you are trying to do. That=20
does indeed require help from WG5.

Best,
Aleks