On Thu, May 31, 2012 at 6:20 AM, Jeff Squyres <jsquy...@cisco.com> wrote:
> On May 29, 2012, at 11:42 AM, Jed Brown wrote: > > > The pkg-config approach is to use pkg-config --static if you want to > link that library statically. > > Do the OMPI pkg-config files not do this properly? > Looks right to me. I think the complaint was that there was no way to specify the equivalent using wrapper compilers. I don't like the wrapper compiler model (certainly not for languages with a common ABI like C), but pkg-config doesn't have a good way to manage multiple configurations. > > > So the problem is almost exclusively one of binary compatibility. If an > app or library is only linked to the interface libs, underlying system > libraries can be upgraded to different soname without needing to relink the > applications. For example, libhwloc could be upgraded to a different ABI, > Open MPI rebuilt, and then the user application and intermediate MPI-based > libraries would not need to be rebuilt. This is great for distributions and > convenient if you work on projects with lots of dependencies. > > > > It's not such an issue for HPC applications because we tend to recompile > a lot and don't need binary compatibility for many of the most common use > cases. There is also the linker option -Wl,--as-needed that usually does > what is desired. > > Mmmm. Ok. Brian and I are going to be in the same physical location next > week; I'll chat with him about this.
