The Darwin version of ranlib does not make common definitions
available in the archive table of contents -- unless you pass it the
"-c" option. Most other versions of ranlib do make such definitions
available, and GCC presently depends on that behavior, accidentally.
(On a meta note, how is libbackend.a a win? I'd love it if we really
have a library for the back end, but we don't, and to get there we
need to change the code, not the build process. Right now, it seems
like building this .a file is just a way of slowing down the
bootstrap...)
Tested on powerpc-apple-darwin7.4.0, installed on the mainline.