+;; Correct argument type restrictions for these functions are
+;; complicated, so we just declare them to accept LISTs and suppress
+;; flushing is safe code.
+(defknown (caar cadr cdar cddr
+ caaar caadr cadar caddr cdaar cdadr cddar cdddr
+ caaaar caaadr caadar caaddr cadaar cadadr caddar cadddr
+ cdaaar cdaadr cdadar cdaddr cddaar cddadr cdddar cddddr
+ second third fourth fifth sixth seventh eighth ninth tenth)
+ (list)
+ t
+ (foldable unsafely-flushable))
+