libreadline only used with psql?

I've grepped through the source code, and the only thing I can find
that uses readline (or libedit) is psql.

Is that correct?

If that's the case, how hard would it be to link only psql with
readline (or libedit)?

Currently, if you ./configure with readline support, -lreadine (or -
ledit) is added to the used-by-everything LIBS variable. Can we
create a PSQL_LIBS variable and have ./configure populate that with
libraries that will only be needed by psql? That way, ./configure can
put -lreadline there and keep it out of LIBS so all the other
binaries (postmaster, pg_ctl, pg_dump, pg_restore, etc) won't require
it.

This request would be accompanied by a patch, but I wanted to ask
about the feasibility of a PSQL_LIBS variable before going down that
road.

Thanks!

- Chris