[MPI3 Fortran] MPI buffer arguments - void and call-by-reference

[N.M. Maclaren]

On Feb 19 2009, Bill Long wrote:
>
>I would note (for the MPI folks) that discussions at J3 meetings suggest 
>that Aleks is not the only one who would like a "modern" MPI interface 
>for Fortran.

Dead right!  And not just in J3.

>  The hard reality is that there is a enormous amount of 
>legacy MPI code out there and the "don't make me change my code" crowd 
>is a significant fraction (most likely the majority) of MPI/Fortran 
>users.  So, I think that continuing to support the current style of 
>interface is not really optional.  The question is whether to support an 
>additional interface that is more in tune with modern Fortran, and 
>offers definite advantages to authors of new codes. I don't think it is 
>either/or, but rather one or two.

I agree.  And my view is that attempting to do both in a single call is
just making life too difficult.  Saying about the existing interface "this
is non-standard, so check with your compiler documentation whether it works
and how to do that" is merely describing the current situation.  Which is
livable with, even if not nice.


Regards,
Nick Maclaren,
University of Cambridge Computing Service,
New Museums Site, Pembroke Street, Cambridge CB2 3QH, England.
Email:  nmm1 at cam.ac.uk
Tel.:  +44 1223 334761    Fax:  +44 1223 334679