[MPI3 Fortran] Argument data sizes

[Jeff Squyres]

On Sep 18, 2008, at 5:02 PM, Aleksandar Donev wrote:

>> I also vote #1, but I'm probably the least informed on this thread as
>> to what real Fortran programmers want.
> Perhaps this straw vote should use preference-based ranking. I am  
> not opposed
> to #1. I don't see the difference between 1 and 2. I dislike 3--- 
> generic
> overloading should be reserved for meaningful uses (such as changing  
> argument
> lists), not this kind of silliness, IMO.

Fair enough.

I agree; #1 and #2 are pretty much the same.  I prefer the MPI_*  
prefix on the name, but only because we have a precedent for that  
already.  I like the fact that implementations would have a mechanism  
to increase the size in future versions, probably without harming user  
codes (this is part of the problem with increasing the count size in  
the C bindings).

#3 is also icky, but it would prevent providers having to ship 2  
libraries.

I dislike #4 (i.e., the current state of today) because it effectively  
introduces an ambiguity in the interface (because compilers can adjust  
the default size of INTEGER).  Sure, we providers *can* ship multiple  
libraries, but it's pretty weird that we would have to do so.  Fixing  
the width to some value -- any value -- would remove this ambiguity  
and create firm interface contracts that don't change with specific  
compiler options.

It seems like this comes back down to the whole "multiple language  
interoperability" set of issues again.  :-)

Just my $0.00000000001.

-- 
Jeff Squyres
Cisco Systems