[MPI3 Fortran] Argument data sizes

[Jeff Squyres]

On Sep 18, 2008, at 2:02 PM, Bill Long wrote:

>> Let's also acknowledge that a significant "artificial constraint"  
>> is backwards compatibility for existing applications.  We can't  
>> just change all the C bindings to make the millions of lines of MPI  
>> code out there no longer be compilable.
>
> I agree that backward compatibility is a good thing.  However, are  
> not the C bindings insulated from this?  If the new interface  
> specifies intptr_t  for the count argument, and the existing program  
> supplies an int (conforming to the old standard) the argument will  
> be automatically promoted in the caller.  I guess I don't see a  
> problem there.

I am happy to talk about backward compatibility and why it can be a  
problem in the context of the larger MPI Forum discussion about this  
issue.

-- 
Jeff Squyres
Cisco Systems