- (do ((index 0 (1+ index))
- (length (%instance-length struct))
- (circ (fasl-output-circularity-table file)))
- ((= index length)
+ (aver (%instance-ref struct 0))
+ (do* ((length (%instance-length struct))
+ (ntagged (- length (layout-n-untagged-slots (%instance-ref struct 0))))
+ (circ (fasl-output-circularity-table file))
+ ;; last slot first on the stack, so that the layout is on top:
+ (index (1- length) (1- index)))
+ ((minusp index)