Arrrgh. I think I figured out GCC's problem (they're requiring
something from /proc/meminfo. I'll file a bug shortly). However,
after 2 hours of running the GCC testsuite, proc threw up.
I don't think we should disable the GCC testsuite in the package just
to compensate for bugs in the Hurd.
It's easy enough to disable the testsuite by hand, though. Does
someone want to take over the task of manually building it when new
versions come out? You need to be a Debian developer. I can also show
you how to build binutils in a safe way.