The dev-libs/librep ebuild installs an Emacs lisp file rep-debugger.el unconditionally, without honoring the "emacs" USE flag. Furthermore, proper support in Emacs (e.g., auto-loading) is not enabled. Patches and a proper site-init file for Emacs will follow.
Created attachment 163039 [details, diff] Proposed changes for librep-0.17_p20070101.ebuild
Created attachment 163043 [details, diff] Proposed changes for librep-0.17_p20070101.ebuild Take 2, right patch this time.
Created attachment 163045 [details, diff] files/librep-0.17_p20070101-disable-elisp.patch
Created attachment 163047 [details] files/50librep-gentoo.el
Thanks, that looks good. Done.