Sorry for the high latency reply. I thought about this quite a bit today. Here's a thinking-out-of-the-box question: should we just use the default/system installed libltdl instead of embedding? If we don't embed, many of these problems go away, right? I.e., we can still have the same options for plugins: non-default, but available if you ask for it *and* there's a system-level libltdl available.
FWIW: I see RHEL 6.x uses libtool/libltdl 2.2.6. Do we: a) care about supporting plugins by default on distros with older ltdl versions? b) use any functionality beyond libltdl 2.2.6? (or some other older/benchmark distro ltdl version that we care about supporting) Attached is a patch that does a few minor things: - avoid the use of AM_CONDITIONAL for the libltdl subdir - ensure to have libtool avoid setting up Fortran and C++ (a trick we learned from MPICH :-) ) - disallow embedded mode and plugins (per our phone discussion the other day) - reorder the plugins support AC_MSG_RESULT to come before any WARN/ERROR messages On Apr 30, 2013, at 5:30 AM, Brice Goglin <brice.gog...@inria.fr> wrote: > Jeff, > > I've been working on making hwloc v1.7 pass our tests/embedded scripts > in the last days. I fixed some minor issues but here's the remaining > (big) one. > > First problem is that we need the AM_CONDITIONAL for HWLOC_LTDL_INCLUDED > to be executed when embedded. I can fix this by moving into > HWLOC_DO_AM_CONDITIONAL. But... > > We conditionally enable SUBDIRS=libltdl (in src/Makefile.am) when > plugins are enabled and the internal ltdl is used. Assuming embedders > don't want hwloc plugins, this builds fine since we don't enter libltdl > during "make", and we can avoid the (ugly) ltdl configuration entirely > [1]. But "make distclean" still enters libltdl unconditionally, and it > fails if LTDL wasn't configured because the Makefile is missing. > > For the record, you had a similar issue with doc/tests/tools where you > don't even have a Makefile.am in these directories in OMPI. You fixed it > by doing DIST_SUBDIRS=$(SUBDIRS). It means that distclean doesn't enter > those directories at all. But it also means that you don't get > doc/tests/tools in make dist when embedded is enabled. We don't build > hwloc tarballs in embedded mode so that's fine. Using the same idea for > my issue would require to build hwloc tarballs with plugins enabled and > ltld included (both non default), I don't thing we should to this way. > > So we need a way to have src/libltdl stay in DIST_SUBDIRS by default, go > in SUBDIRS when needed, and disappear totally when embedded. So here's > the only solution I finally found: hwloc configure.ac sets a shell > variable to yes, and a new AM_CONDITIONAL adds src/libltdl to > DIST_SUBDIRS only when this variable is "yes". > This still causes hwloc tarballs to contain libltdl (because hwloc > configure.ac sets the variable to yes). It's still enabled only when the > system doesn't have libltdl installed or --with-included-ltdl is given, > as previously. And embedders totally ignore src/libltdl, including in > distclean, because they don't set the variable to yes. > > If an embedder ever wants to use hwloc plugins, he will have to > duplicate what the hwloc configure.ac does [1], and it can still link > with another libltdl if needed (to be tested). > > Patch attached, on top of trunk. Note that you may need these additional > commits if you or Pavan want to test things [2] > > Let me know what you think because you have the same problem as Pavan > when OMPI switches to hwloc v1.6+ > > Brice > > > > > [1] Enabling ltdl requires some code like below:configure.ac > AM_PROG_LIBTOOL([dlopen win32-dll]) > LT_LANG([C]) > # Here's what we need to configure ltdl properly > LT_CONFIG_LTDL_DIR([src/libltdl]) > LTDL_INIT([recursive convenience]) > AC_CONFIG_FILES([src/libltdl/Makefile]) > # Tell src/Makefile.am that things were configured under src/libltdl/ > hwloc_mayenter_src_libltdl=yes > > libtool doesn't seem to like having it in a HWLOC_SETUP_LTDL macro > outside of the main, and I think we have to let embedders call > AM_PROG_LIBTOOL() directly in case they need other options. > > There's also a hack below these lines that is specific to the > "recursive" mode, but we may switch to "subproject" mode (hwloc > configure explicitly calls libltdl configure) at some point if libtool > doesn't fix the issue. > > [2] > https://svn.open-mpi.org/trac/hwloc/changeset/5563 > https://svn.open-mpi.org/trac/hwloc/changeset/5562 > > <ltdl.patch> -- Jeff Squyres jsquy...@cisco.com For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/
