To compile alexandria with the latest CCL, I had to move sequence-of-length-p near the top of sequences.lisp (just below the declaim) least the local (declare (inline ...)) of it would cause CCL to bork, complaining that you're trying to inline a function that hasn't been defined yet.
I believe that CCL is justified in complaining and that alexandria upstream should be modified similarly.
[ François-René ÐVB Rideau | Reflection&Cybernethics | http://fare.tunes.org ] Down to Gehenna or up to the Throne, He travels the fastest who travels alone. -- Rudyard Kipling