Jeff is right. Bill's theoretical statement is also correct. And ticket#415 is also correct because it resolves an inconsistency within the mpi_f08 interface. Strange theoretical discussions are also there for long Fortran INTEGER may not be identical with some shorter INTEGER(C_int). As a side effect also solved by this ticket. Rolf ----- Original Message -----

From: "Jeff Hammond" <[email protected]> To: "MPI-WG Fortran working group" mpi-forum.org> Sent: Thursday, March 13, 2014 4:12:56 PM Subject: Re: [MPIWG Fortran] Type of MPI_Status

MPI should test for interoperability of Fortran's default integer and light the machine room on fire if it is not.

Jeff

On Thu, Mar 13, 2014 at 8:58 AM, Bill Long <[email protected]> wrote:

...

This does raise an earlier issue that it is possible that Fortran’s default INTEGER is not an interoperable type, and thus the MPI_Status type should not be a BIND(C) type if it has INTEGER components. Having BIND(C) does allow you to declare a C global name MPI_STATUS_IGNORE in Fortran, which solves one problem nicely. I don’t see any advantage to having INTEGER components (as opposed to INTEGER(C_Int), for example). So this seems to represent the worse of the two options.

Cheers, Bill

On Mar 13, 2014, at 8:36 AM, Jeff Squyres (jsquyres) <[email protected]> wrote:

...

Done. Good catch:

https://svn.mpi-forum.org/trac/mpi-forum-web/ticket/415

This is a trivial ticket, but if you could make sure it's ok, I'll send it to the mpi-forum list so that it can get added to the next meeting's agenda.

On Mar 13, 2014, at 1:51 AM, Rolf Rabenseifner <[email protected]> wrote:

...

Jeff and Junchao,

it is a missing word INTEGER in this part of the sentence

In whole MPI these three values are in Fortran INTEGER and nothing else

Junchao, thank you for the hint that an erratum is neede to prevent from such misinterpretation

Jeff, please can you file the errata ticket resulting in

... containing three public INTEGER fields named ...

Best regards Rolf

----- Original Message -----

...

From: "Junchao Zhang" <[email protected]> To: "MPI-WG Fortran working group" mpi-forum.org> Sent: Thursday, March 13, 2014 4:49:49 AM Subject: [MPIWG Fortran] Type of MPI_Status

Hello,

p30 of MPI3 says "In Fortran with USE mpi or INCLUDE ’mpif.h’, status is an array of INTEGERs of size MPI_STATUS_SIZE. ..., With Fortran USE mpi_f08, status is defined as the Fortran BIND(C) derived type TYPE(MPI_Status) containing three public fields named MPI_SOURCE , MPI_TAG , and MPI_ERROR"

In other words, it does't say type of the three public fields must be INTEGER. So, in mpi_f08, can I declare MPI_Status as

TYPE, BIND(C) :: MPI_Status INTEGER(C_INT) :: MPI_SOURCE, MPI_TAG, MPI_ERROR ... ! other fields END TYPE MPI_Status

I find it makes MPI_Status binding easier. Since this type is interoperable with C, I do not need to allocate temp variables to do type conversion when INTEGER is not a C_INT.

--Junchao Zhang _______________________________________________ mpiwg-fortran mailing list [email protected] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-fortran

-- Dr. Rolf Rabenseifner . . . . . . . . . .. email [email protected] 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) _______________________________________________ mpiwg-fortran mailing list [email protected] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-fortran

-- Jeff Squyres [email protected] For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/

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-- Jeff Hammond [email protected] _______________________________________________ mpiwg-fortran mailing list [email protected] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-fortran

-- Dr. Rolf Rabenseifner . . . . . . . . . .. email [email protected] 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)