Having spent more time than I care to imagine waiting for 'opt' to link, I
finally got frustrated enough to do something about it. As it turns out,
the problem was already fixed.
If you're working on LLVM, and using the GNU linker, I _highly_ _highly_
_highly_ recommend grabbing the CVS version of binutils
(http://sources.redhat.com/binutils/) and using it.
For me, it reduced the TTLO (time to link opt) from 61s to 9s (on a
3.2ghz P4 Xeon).