[mpiwg-p2p] Review of Pythonization changes for Chapter 3

Rolf Rabenseifner rabenseifner at hlrs.de
Sat Jan 25 11:54:48 CST 2020


Dear Dan and Bill,

Yes, Bill, and more than that: Fortran INTENT(OUT) means that the Compiler may through
the Input away, i.e., if a field should not be changed, e.g. because there is no 
such Output of Status (e.g. WAIT for a send request), then the status my be changed
into some undefined values.

Therefore, we ware very careful for the mpi_f08 module never to add a risky INTENT(OUT).

Best regards
Rolf


----- Original Message -----
> From: "MPI WG Point To Point Communications working group" <mpiwg-p2p at lists.mpi-forum.org>
> To: "MPI WG Point To Point Communications working group" <mpiwg-p2p at lists.mpi-forum.org>
> Cc: "wgropp" <wgropp at illinois.edu>
> Sent: Saturday, January 25, 2020 6:04:12 PM
> Subject: Re: [mpiwg-p2p] Review of Pythonization changes for Chapter 3

> I believe this choice is because of MPI_STATUS_IGNORE - there is, in fact, both
> an IN value (don’t fill in the status) and an OUT value (place the status value
> here). We do note in the intro that the MPI IN and OUT do not exactly match
> Fortran, for these reasons.
> 
> Bill
> 
> William Gropp
> Director and Chief Scientist, NCSA
> Thomas M. Siebel Chair in Computer Science
> University of Illinois Urbana-Champaign
> 
> 
> On Jan 22, 2020, at 5:07 AM, HOLMES Daniel via mpiwg-p2p < [
> mailto:mpiwg-p2p at lists.mpi-forum.org | mpiwg-p2p at lists.mpi-forum.org ] > wrote:
> 
> 3) The F08 bindings for all variants of the MPI_TEST, MPI_WAIT, and MPI_PROBE
> functions and the MPI_REQUEST_GET_STATUS function do not specify an INTENT for
> the status(es) parameter. We could fix this by including “INTENT(OUT)” in all
> cases (by choosing the correct Python setting).
> 
> 
> 
> _______________________________________________
> mpiwg-p2p mailing list
> mpiwg-p2p at lists.mpi-forum.org
> https://lists.mpi-forum.org/mailman/listinfo/mpiwg-p2p

-- 
Dr. Rolf Rabenseifner . . . . . . . . . .. email rabenseifner at hlrs.de .
High Performance Computing Center (HLRS) . phone ++49(0)711/685-65530 .
University of Stuttgart . . . . . . . . .. fax ++49(0)711 / 685-65832 .
Head of Dpmt Parallel Computing . . . www.hlrs.de/people/rabenseifner .
Nobelstr. 19, D-70550 Stuttgart, Germany . . . . (Office: Room 1.307) .


More information about the mpiwg-p2p mailing list