Open MPI logo

Hardware Locality Development Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Hardware Locality Development mailing list

Subject: [hwloc-devel] hwloc-1.7 issue roundup
From: Pavan Balaji (balaji_at_[hidden])
Date: 2013-05-05 12:18:35


All,

Sorry for starting a new thread. I'm trying to round-up all the issues
I've reported for hwloc-1.7 so far into a more manageable format.

1. We had noticed errors with -D_POSIX_SOURCE that I had reported here:

http://www.open-mpi.org/community/lists/hwloc-devel/2013/04/3649.php

The error with POSIX_SOURCE itself was pretty straightforward. I was
able to fix it in the mpich version:

http://git.mpich.org/mpich.git/commitdiff/255da3f6

However, with our complete strict build flags, there were more errors.
Here's a summary and the relevant fixes:

 - hwloc's check for whether an explicitly function declaration is
needed (using _HWLOC_CHECK_DECL) was relying on whether a dummy call to
the function throws an error. This only works if the function
declaration is already present in one of the headers. If such a
declaration is not present, the test might fail with "implicit function
declaration" with the right CFLAGS. This leads the m4 macro to think
that the declaration is already there in one of the headers and an
additional declaration is not needed.

The below commit fixes this by adding a dummy function declaration,
together with the dummy function definition:

http://git.mpich.org/mpich.git/commitdiff/90da6e90

FWIW, mpich's version of this macro also uses a similar dummy function
declaration together with the dummy call to the function:

http://git.mpich.org/mpich.git/blob/HEAD:/confdb/aclocal_cc.m4#l1215

 - For sysctl and sysctlbyname, I've updated hwloc/config.m4 to use a
full link test instead of just using AC_CHECK_FUNCS, which only checks
to see if the symbol exists or not. For example, the prototype of
sysctl uses u_int, which on some platforms (such as FreeBSD) is only
defined under __BSD_VISIBLE, __USE_BSD or other similar definitions. So
while the symbols "sysctl" and "sysctlbyname" might still be available
in libc (which autoconf checks for), they might not be actually usable.

The below commit fixes this:

http://git.mpich.org/mpich.git/commitdiff/db276e4e

 - A minor error where strings.h was not included for strcasecmp.

http://git.mpich.org/mpich.git/commitdiff/d2338c2d

2. I had reported an issue with libltdl in embedded mode (also in the
above thread). I believe Brice is looking into this, so I didn't
investigate it further. I'm using a disgusting, but workable, patch to
workaround this error in mpich (see the
src/pm/hydra/tools/topo/hwloc/hwloc/src/Makefile.am part of the below
patch):

http://git.mpich.org/mpich.git/commitdiff/a3bce754

I'd appreciate a cleaner fix to this issue.

3. I had reported an issue with the usage of getpagesize() instead of
hwloc_getpagesize() on the Mac.

http://www.open-mpi.org/community/lists/hwloc-devel/2013/05/3662.php

I believe Samuel has already incorporated this in hwloc trunk. Here is
the fix I used for your reference:

http://git.mpich.org/mpich.git/commitdiff/d9a67f40

4. I had reported some warnings on the FreeBSD strict build here.

http://www.open-mpi.org/community/lists/hwloc-devel/2013/05/3669.php

I believe Brice and Samuel are looking into it, but I don't have a
confirmation on whether this is fixed. I didn't fix them in mpich yet.

As you can tell, we are looking into upgrading to hwloc-1.7 for the next
major release of mpich (3.1). With the above fixes, it looks like
things are working well. Of course, we'll be going through a lot more
testing before the final release which would be later this year.

 -- Pavan

-- 
Pavan Balaji
http://www.mcs.anl.gov/~balaji