+(defparameter *bar* nil)
+(declaim (inline make-nested-bad make-nested-good))
+(defstruct (nested (:constructor make-nested-bad (&key bar &aux (bar (setf *bar* bar))))
+ (:constructor make-nested-good (&key bar)))
+ bar)
+
+(defun-with-dx nested-good (y)
+ (let ((x (list (list (make-nested-good :bar (list (list (make-nested-good :bar (list y)))))))))
+ (declare (dynamic-extent x))
+ (true x)))
+
+(defun-with-dx nested-bad (y)
+ (let ((x (list (list (make-nested-bad :bar (list (list (make-nested-bad :bar (list y)))))))))
+ (declare (dynamic-extent x))
+ (unless (equalp (caar x) (make-nested-good :bar *bar*))
+ (error "got ~S, wanted ~S" (caar x) (make-nested-good :bar *bar*)))
+ (caar x)))
+
+(with-test (:name :conservative-nested-dx)
+ ;; NESTED-BAD should not stack-allocate :BAR due to the SETF.
+ (assert (equalp (nested-bad 42) (make-nested-good :bar *bar*)))
+ (assert (equalp *bar* (list (list (make-nested-bad :bar (list 42)))))))
+