+ (source-location nil)
+ ;; Information about slots in the class to PCL: this provides fast
+ ;; access to slot-definitions and locations by name, etc.
+ (slot-table #(nil) :type simple-vector)
+ ;; True IFF the layout belongs to a standand-instance or a
+ ;; standard-funcallable-instance -- that is, true only if the layout
+ ;; is really a wrapper.
+ ;;
+ ;; FIXME: If we unify wrappers and layouts this can go away, since
+ ;; it is only used in SB-PCL::EMIT-FETCH-WRAPPERS, which can then
+ ;; use INSTANCE-SLOTS-LAYOUT instead (if there is are no slot
+ ;; layouts, there are no slots for it to pull.)
+ (for-std-class-p nil :type boolean :read-only t))