[MPI3 Fortran] [Interop-tr] [Mpi-forum] Comment on Fortran WG5 ballot N1846

[Van Snyder]

On Tue, 2011-04-19 at 14:53 -0700, Jeff Squyres wrote:
> 
> 1. The signature of MPI_WAIT (and friends) has been around for 18
> years and there's lots of codes using it.  It would be fairly
> disruptive to change it.
> 
> This may be a weak argument; the other 2 are stronger.
> 
> 2. The request passed to MPI_WAIT may not have a buffer associated
> with it.  MPI has lots of types of requests, not just non-blocking
> point-to-point communication requests.
> 
> 3. Other flavors of MPI_WAIT take arrays of requests (e.g.,
> MPI_WAITALL). We'd have to pass an array of buffers corresponding to
> the array of requests, which would just be plain icky (would you have
> to have an array of fortran pointers to refer to all the requisite
> buffers?).

This is what Fortran generic interfaces, or optional arguments, are for.