From elisp-common.eclass: Commands as "load-library" or "require" bloat the editor as they are loaded on every startup. When having a lot of Emacs support files, users may be annoyed by the start-up time. Also avoid keybindings as they might interfere with the user's settings. This is a tracker bug for issues with Emacs site-init files.
Additional infos can be found on http://overlays.gentoo.org/proj/emacs/wiki/sitefile%20problems Those packages there will eventually fixed.
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