Comment 3 for bug 551227

This is (similar) code from macroexpansion of `some' compiler macro:

#'(lambda (a)
    (if (funcall #'(lambda (p s)
                     (block :block
                       (map nil
                            #'(lambda (e)
                                (return-from :block (funcall p e)))
                            s)))
                 #'(lambda (x) (f (mod a x)))
                 a)
        (g a)))

and it ruins on ir1 phase - sb-c::node-home-lambda (from ir1utils.lisp) get this NIL value.