[Mpi-forum] Reserved MPI_ prefix & namespace in C and Fortran

Sat Aug 25 11:29:44 CDT 2012

Martin, Dave and Kathryn:

Do you agree with Rolf's suggested addition for the
tools chapter? I am ambivalent but will make the
change and send it to Rich if you do.

Bronis

On Sat, 25 Aug 2012, Rolf Rabenseifner wrote:

> Okay, we should refer in both directions:
>
> Add additional the sentence after MPI-3.0 Draft 2, page 19 line 16
> (MPI-2.2 p18:17):
>
>      The MPI_ prefix reservation is relaxed when the profiling
>      interface is used, see Section 14.2.2 on page 558 for details.
>
> Same sentence for Fortran after MPI-3.0 Draft 2 p18:42 / MPI-2.2 p17:44.
> For C++, the following is needed after MPI-2.2 p18:41:
>
>      The MPI namespace reservation is relaxed when the profiling
>      interface is used, see Section 14.2.2 on page 558 for details.
>
> And:
>>> Add a new sentence after MPI-2.2, Chapter 14 "Profiling",
>>> Sect. 14.2 "Discussion", page 454, line 17,
>>> respectively, after MPI-3.0 Draft 2, Section 14.2 "Profiling",
>>> Sect. 14.2.2 "Discussion", page 558, line 34/35:
>>>
>>>   Typically, the profiling interface is used by implementing
>>>   a new application or profiling function that has the same
>>>   name as an MPI routine and internally calls the corresponding
>>>   PMPI routine; this is an exception to the name prefix
>>>   reservation rules in Sections 2.6.2 and 2.6.3 on pages 18 and 19.
>>>
>
> Good so?
>
> Rolf
>
> ----- Original Message -----
>> From: "Bronis R. de Supinski" <bronis at llnl.gov>
>> To: "Rolf Rabenseifner" <rabenseifner at hlrs.de>
>> Cc: "Martin Schulz" <schulzm at llnl.gov>, "Dave Goodell" <goodell at mcs.anl.gov>, "Kathryn Mohror" <mohror1 at llnl.gov>,
>> "Main MPI Forum mailing list" <mpi-forum at lists.mpi-forum.org>
>> Sent: Saturday, August 25, 2012 4:39:53 PM
>> Subject: Re: [Mpi-forum] Reserved MPI_ prefix & namespace in C and Fortran
>> I agree with Bill that the right solution is a forward
>> reference at the point the restriction is defined. It
>> will be lost if we bury it in the tools chapter.
>>
>> On Sat, 25 Aug 2012, Rolf Rabenseifner wrote:
>>
>>> Bronis, Martin, Dave, Kathryn, and all tools people,
>>>
>>> Yes, we should also solve this 2nd inconsistency about
>>> defining MPI_Xxxx with real MPI-names when writing a tools layer,
>>> which is inconsistent with the prefix reservation in Sect.
>>> 2.6.2-2.6.4
>>> with the original wording and also with the new wording below.
>>>
>>> Here, I would propose to relax the prefix reservation defined in
>>> Sections 2.6.2 - 2.6.4 by a sentence in the tools chapter
>>> that refers to Sect. 2.6.2-2.6.4.
>>>
>>> Proposed solution (please take it a s a first draft):
>>>
>>> Add a new sentence after MPI-2.2, Chapter 14 "Profiling",
>>> Sect. 14.2 "Discussion", page 454, line 17,
>>> respectively, after MPI-3.0 Draft 2, Section 14.2 "Profiling",
>>> Sect. 14.2.2 "Discussion", page 558, line 34/35:
>>>
>>>   Typically, the profiling interface is used by implementing
>>>   a new application or profiling function that has the same
>>>   name as an MPI routine and internally calls the corresponding
>>>   PMPI routine; this is an exception to the name prefix
>>>   reservation rules in Sections 2.6.2 and 2.6.3 on pages 18 and 19.
>>>
>>> Because this is specific to the profiling layer, I would not
>>> stress the wording in the Terms chapter. The right position
>>> is really the tools chapter.
>>>
>>> You, as the tools group may find a better wording and fine grained
>>> position of this sentence. Important is, that this sentence
>>> only solves the existing inconsistency, because this is the scope
>>> of this erratum.
>>>
>>> Okay? Better proposals? Comments?
>>>
>>> -----------------------------------
>>> Here again the latest version of the text in Sections 2.6.2 - 2.6.4:
>>>
>>> C:
>>>>   "Programs must not declare
>>>       names (identifiers), e.g., for variables, functions,
>>>       constants, types, or macros,
>>>>    beginning with the prefix MPI_."
>>>
>>> Fortran:
>>>>   "Programs must not declare
>>>       names, e.g., for variables, subroutines, functions,
>>>       parameters, derived types, abstract interfaces, or modules,
>>>>    beginning with the prefix MPI_.
>>>
>>> and for Fortran also "subroutines and functions" instead of
>>> only "functions" in the sentence about PMPI_.
>>>
>>> C++
>>>>   "Programs must not declare
>>>       names (identifiers), e.g., for variables, functions,
>>>       constants, types, or macros,
>>>>    in the namespace MPI."
>>> -----------------------------------
>>>
>>> Best regards
>>> Rolf
>>>
>>> ----- Original Message -----
>>>> From: "Bronis R. de Supinski" <bronis at llnl.gov>
>>>> To: "Main MPI Forum mailing list" <mpi-forum at lists.mpi-forum.org>
>>>> Sent: Saturday, August 25, 2012 2:34:38 PM
>>>> Subject: Re: [Mpi-forum] Reserved MPI_ prefix & namespace in C and
>>>> Fortran
>>>> So, while we are debating whether the wording is sufficient,
>>>> we are overlooking a far more important error in the restriction.
>>>> It is simply wrong. The standard is not consistent.
>>>>
>>>> Specifically, when one uses the MPI profiling interface, the
>>>> mechanism is precisely to declare functions that begin with
>>>> MPI_. So the intent of the standard is that we are supposed
>>>> to violate that restriction. This issue has nagged at me in
>>>> the past but I have simply ignored it. However, I would oppose
>>>> increasing the scope of the restriction without fixing the
>>>> real inconsistency.
>>>> _______________________________________________
>>>> mpi-forum mailing list
>>>> mpi-forum at lists.mpi-forum.org
>>>> http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi-forum
>>>
>>> --
>>> 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: Allmandring 30)
>>>
>
> -- 
> 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: Allmandring 30)
>