I recently upgraded OMPI's SVN trunk to hwloc 1.4.2, and immediately broke builds on Solaris.  After some hunting around, here's what our friends at Oracle have found:

- Building hwloc 1.4.2 standalone on Solaris works fine.
- Building OMPI SVN trunk (with hwloc 1.4.2 embedded) on Solaris fails due to a missing -lpicl.
- The issue seems to be in hwloc's src/Makefile.am:

   if HWLOC_HAVE_SOLARIS
   ldflags += -lpicl
   endif HWLOC_HAVE_SOLARIS

Specifically, -lpicl gets added to standalone builds but not embedded builds.

Shouldn't the check for -lpicl be in hwloc.m4 so that it gets added to HWLOC_EMBEDDED_LIBS?  See the attached patch.

Or is there a deeper reason we didn't use AC_CHECK_LIB and used HWLOC_HAVE_SOLARIS instead?  (e.g., is -lpicl Bad on other platforms?)