[Mpi-22] MPI-2.1 ambiguity?

[Jeff Squyres]

On Jul 17, 2008, at 10:03 AM, William Gropp wrote:

> To make this perfectly clear, should the standard state that the  
> values of the predefined datatypes from another language are exactly  
> the same as the value produced by the handle conversion function?   
> E.g., in Fortran, the value of MPI_INT is what you would get from  
> MPI_TYPE_C2F( MPI_INT )  (where MPI_INT is the C version).  It  
> should also state that just because Fortran defines MPI_LONG_LONG,  
> that does not imply that Fortran support an integer type that  
> corresponds to the C long long type.

I think I agree with the idea (you can use MPI_INT in Fortran just  
like you would use MPI_INT in C just like you would use MPI::INT in C+ 
+), but your exact idea doesn't seem to work for C++.  For example,  
what about MPI::INTEGER?

I had assumed that the only use of MPI_INT in Fortran would be used  
for Fortran to pass a buffer to an MPI function that was pre-filled  
with int's in C (and other similar cases like this).  Is that  
consistent with what you're suggesting?


-- 
Jeff Squyres
Cisco Systems