While we're benchmarking various configurations of the toolchain:
I'd also be interested in the impact on total build-time of
interposing this `/usr/libexec/collect2' program.

Beside the usual start-up overhead of yet another wrapper, this program
also is pretty senseless when going about the thing it wants to do:
it probes about every corner of the system looking for the native
link-editor.  I've not tried to find out what the thing is that
it wants to do, but I'm pretty sure its services are not even needed
to build our system.

-pk