Not sure if it's relevant but this is for an overlay. Not 'normal' portage. dev-lisp/trivial-garbage (And possibly more) http://common-lisp.net/~lolivera no longer exists
What overlay?
Gentoo's lisp in layman layman -a lisp http://git.overlays.gentoo.org/gitweb/?p=proj/lisp.git * lisp [Git ] (git://git.o.g.o/proj/lisp.git, ht...)
Bumped to 0.20. SRC_URI now points to github.