Re: [OMPI devel] PGI built Open MPI vs GNU built slurm

[Paul Hargrove]

Gilles,

With the additional information you provided about "dependency_libs", I
agree that that either of the fixes you propose sound safe.

-Paul

On Mon, Jul 25, 2016 at 6:26 PM, Gilles Gouaillardet 
wrote:

> Paul,
>
> in my environment, libslurm.la contains
>
> # Linker flags that can not go in dependency_libs.
> inherited_linker_flags=' -pthread'
>
> # Libraries that this one depends upon.
> dependency_libs=' -ldl -lpthread'
>
>
> so bottom line, it invokes the compiler with both -pthread and -lpthread
>
>
> iirc, -pthread does two things :
>
> - invoke the compiler with -D_REENTRANT (so it uses the thread-safe errno
> and so on)
>
> - invoke the linker with -lpthread
>
> OpenMPI has its own way to pass -D_REENTRANT or similar anyway, and
> libslurm.la is used only for for linking.
>
> since -lpthread is pulled anyway from libslurm.la (or it was already set
> by OpenMPI), then yes, discarding -pthread should do the trick.
>
>
> Cheers,
>
>
> Gilles
>
> On 7/26/2016 10:11 AM, Paul Hargrove wrote:
>
> Gilles,
>
> My initial thought is that libslurm probably does require linking
> libpthread, either for for linking pthread_* symbols, or for proper
> *operation* (such as thread-safe versions of functions which override weak
> definitions in libc).
>
> If so, then neither omitting "-pthread" nor telling pgcc not to complain
> about "-pthread" is going to be a good solution.
> Instead the "-pthread" needs to be replaced by "-lpthread", or similar.
>
> -Paul
>
> On Mon, Jul 25, 2016 at 6:03 PM, Gilles Gouaillardet 
> wrote:
>
>> Folks,
>>
>>
>> This is a followup of a thread that initially started at
>> http://www.open-mpi.org/community/lists/users/2016/07/29635.php
>>
>>
>> The user is trying to build Open MPI with PGI compiler and
>> libslurm.la/libpmi.la support, and slurm was built with gcc compiler.
>>
>>
>> At first, it fails because the "-pthread" flag is pulled from
>> libslurm.la/libpmi.la, but this flag is not supported by PGI compilers.
>>
>> A workaround is to pass the -noswitcherror flag to the PGI compiler (so
>> the -pthread flag is discarded and a warning message is issued, but PGI
>> compiler does not fail). Unfortunatly, that does not work because libtool
>> does does not pass this flag to the PGI compiler.
>>
>>
>> Of course, one option is to tell the user to rebuild slurm with PGI, so
>> libslurm.la/libpmi.la do not have the "-pthread" flag.
>>
>> A nicer though arguable option is to hack libtool to silently drop the
>> "-pthread" flag with PGI compiler is used (i made a proof of concept, and
>> this is a two lines patch).
>>
>> An other cleaner option is to hack libtool so it pass -noswitcherror to
>> PGI compiler, but i do not know how to achieve this.
>>
>>
>> Any thoughts ?
>>
>>
>> Cheers
>>
>> ___
>> devel mailing list
>> de...@open-mpi.org
>> Subscription: https://www.open-mpi.org/mailman/listinfo.cgi/devel
>> Link to this post:
>> http://www.open-mpi.org/community/lists/devel/2016/07/19278.php
>>
>
>
>
> --
> Paul H. Hargrove  phhargr...@lbl.gov
> Computer Languages & Systems Software (CLaSS) Group
> Computer Science Department   Tel: +1-510-495-2352
> Lawrence Berkeley National Laboratory Fax: +1-510-486-6900
>
>
> ___
> devel mailing listde...@open-mpi.org
> Subscription: https://www.open-mpi.org/mailman/listinfo.cgi/devel
>
> Link to this post: 
> http://www.open-mpi.org/community/lists/devel/2016/07/19279.php
>
>
>
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> de...@open-mpi.org
> Subscription: https://www.open-mpi.org/mailman/listinfo.cgi/devel
> Link to this post:
> http://www.open-mpi.org/community/lists/devel/2016/07/19280.php
>



-- 
Paul H. Hargrove  phhargr...@lbl.gov
Computer Languages & Systems Software (CLaSS) Group
Computer Science Department   Tel: +1-510-495-2352
Lawrence Berkeley National Laboratory Fax: +1-510-486-6900

Re: [OMPI devel] PGI built Open MPI vs GNU built slurm

[Gilles Gouaillardet]

Paul,

in my environment, libslurm.la contains

# Linker flags that can not go in dependency_libs.
inherited_linker_flags=' -pthread'

# Libraries that this one depends upon.
dependency_libs=' -ldl -lpthread'


so bottom line, it invokes the compiler with both -pthread and -lpthread


iirc, -pthread does two things :

- invoke the compiler with -D_REENTRANT (so it uses the thread-safe 
errno and so on)


- invoke the linker with -lpthread

OpenMPI has its own way to pass -D_REENTRANT or similar anyway, and 
libslurm.la is used only for for linking.


since -lpthread is pulled anyway from libslurm.la (or it was already set 
by OpenMPI), then yes, discarding -pthread should do the trick.



Cheers,


Gilles


On 7/26/2016 10:11 AM, Paul Hargrove wrote:

Gilles,

My initial thought is that libslurm probably does require linking 
libpthread, either for for linking pthread_* symbols, or for proper 
*operation* (such as thread-safe versions of functions which override 
weak definitions in libc).


If so, then neither omitting "-pthread" nor telling pgcc not to 
complain about "-pthread" is going to be a good solution.

Instead the "-pthread" needs to be replaced by "-lpthread", or similar.

-Paul

On Mon, Jul 25, 2016 at 6:03 PM, Gilles Gouaillardet 
mailto:gil...@rist.or.jp>> wrote:


Folks,


This is a followup of a thread that initially started at
http://www.open-mpi.org/community/lists/users/2016/07/29635.php


The user is trying to build Open MPI with PGI compiler and
libslurm.la/libpmi.la  support, and
slurm was built with gcc compiler.


At first, it fails because the "-pthread" flag is pulled from
libslurm.la/libpmi.la , but this
flag is not supported by PGI compilers.

A workaround is to pass the -noswitcherror flag to the PGI
compiler (so the -pthread flag is discarded and a warning message
is issued, but PGI compiler does not fail). Unfortunatly, that
does not work because libtool does does not pass this flag to the
PGI compiler.


Of course, one option is to tell the user to rebuild slurm with
PGI, so libslurm.la/libpmi.la  do
not have the "-pthread" flag.

A nicer though arguable option is to hack libtool to silently drop
the "-pthread" flag with PGI compiler is used (i made a proof of
concept, and this is a two lines patch).

An other cleaner option is to hack libtool so it pass
-noswitcherror to PGI compiler, but i do not know how to achieve this.


Any thoughts ?


Cheers

___
devel mailing list
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Link to this post:
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--
Paul H. Hargrove phhargr...@lbl.gov 
Computer Languages & Systems Software (CLaSS) Group
Computer Science Department   Tel: +1-510-495-2352
Lawrence Berkeley National Laboratory Fax: +1-510-486-6900


___
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Link to this post: 
http://www.open-mpi.org/community/lists/devel/2016/07/19279.php

Re: [OMPI devel] PGI built Open MPI vs GNU built slurm

[Paul Hargrove]

Gilles,

My initial thought is that libslurm probably does require linking
libpthread, either for for linking pthread_* symbols, or for proper
*operation* (such as thread-safe versions of functions which override weak
definitions in libc).

If so, then neither omitting "-pthread" nor telling pgcc not to complain
about "-pthread" is going to be a good solution.
Instead the "-pthread" needs to be replaced by "-lpthread", or similar.

-Paul

On Mon, Jul 25, 2016 at 6:03 PM, Gilles Gouaillardet 
wrote:

> Folks,
>
>
> This is a followup of a thread that initially started at
> http://www.open-mpi.org/community/lists/users/2016/07/29635.php
>
>
> The user is trying to build Open MPI with PGI compiler and
> libslurm.la/libpmi.la support, and slurm was built with gcc compiler.
>
>
> At first, it fails because the "-pthread" flag is pulled from
> libslurm.la/libpmi.la, but this flag is not supported by PGI compilers.
>
> A workaround is to pass the -noswitcherror flag to the PGI compiler (so
> the -pthread flag is discarded and a warning message is issued, but PGI
> compiler does not fail). Unfortunatly, that does not work because libtool
> does does not pass this flag to the PGI compiler.
>
>
> Of course, one option is to tell the user to rebuild slurm with PGI, so
> libslurm.la/libpmi.la do not have the "-pthread" flag.
>
> A nicer though arguable option is to hack libtool to silently drop the
> "-pthread" flag with PGI compiler is used (i made a proof of concept, and
> this is a two lines patch).
>
> An other cleaner option is to hack libtool so it pass -noswitcherror to
> PGI compiler, but i do not know how to achieve this.
>
>
> Any thoughts ?
>
>
> Cheers
>
> ___
> devel mailing list
> de...@open-mpi.org
> Subscription: https://www.open-mpi.org/mailman/listinfo.cgi/devel
> Link to this post:
> http://www.open-mpi.org/community/lists/devel/2016/07/19278.php
>



-- 
Paul H. Hargrove  phhargr...@lbl.gov
Computer Languages & Systems Software (CLaSS) Group
Computer Science Department   Tel: +1-510-495-2352
Lawrence Berkeley National Laboratory Fax: +1-510-486-6900

[OMPI devel] PGI built Open MPI vs GNU built slurm

[Gilles Gouaillardet]

Folks,


This is a followup of a thread that initially started at 
http://www.open-mpi.org/community/lists/users/2016/07/29635.php



The user is trying to build Open MPI with PGI compiler and 
libslurm.la/libpmi.la support, and slurm was built with gcc compiler.



At first, it fails because the "-pthread" flag is pulled from 
libslurm.la/libpmi.la, but this flag is not supported by PGI compilers.


A workaround is to pass the -noswitcherror flag to the PGI compiler (so 
the -pthread flag is discarded and a warning message is issued, but PGI 
compiler does not fail). Unfortunatly, that does not work because 
libtool does does not pass this flag to the PGI compiler.



Of course, one option is to tell the user to rebuild slurm with PGI, so 
libslurm.la/libpmi.la do not have the "-pthread" flag.


A nicer though arguable option is to hack libtool to silently drop the 
"-pthread" flag with PGI compiler is used (i made a proof of concept, 
and this is a two lines patch).


An other cleaner option is to hack libtool so it pass -noswitcherror to 
PGI compiler, but i do not know how to achieve this.



Any thoughts ?


Cheers