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

Sat Aug 25 15:10:30 CDT 2012

Hi Bronis,

The suggested change seems fine to me.

Kathryn

On 8/25/2012 9:29 AM, Bronis R. de Supinski wrote:
>
> 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)
>>

_____________________________________________________________________
Kathryn Mohror, kathryn at llnl.gov, http://people.llnl.gov/mohror1
CASC @ Lawrence Livermore National Laboratory, Livermore, CA, USA