[MPI3 Fortran] Specify IN/OUT/INOUT in MPI spec?

Lionel, Steve steve.lionel at intel.com
Tue May 26 11:58:12 CDT 2009

Jeff Squyres wrote:

"I note that none of the current Fortran API interface specifications  
in MPI-2.1 list the intent of the parameters.  Do we want to update  
all of MPI in 3.0 to list the INTENT, and/or use "more modern Fortran  

Yes, please!  Also, the "integer" and other datatypes should specify a KIND specifier from a set defined in the MPI module.  IMPORT should be used to get these values into the interface block so a separate module for the types and kinds is not required.  See http://software.intel.com/en-us/blogs/2006/10/05/domestic-or-imported/ for an item I wrote on IMPORT.

We should also consider whether BIND(C) and other C interoperability features should be used (especially the KIND values from ISO_C_BINDING that correspond to C types.)

While IMPORT and C interoperability are Fortran 2003 features, most reasonably current Fortran compilers support them.

Steve Lionel
Intel Developer Support
Nashua, NH

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