;;; breakdown of side effects, since we do very little code motion on
;;; IR1. We are interested in some deeper semantic properties such as
;;; whether it is safe to pass stack closures to.
-(def-boolean-attribute ir1
+(!def-boolean-attribute ir1
;; may call functions that are passed as arguments. In order to
;; determine what other effects are present, we must find the
;; effects of all arguments that may be functions.