compiler's type deriver.
392: slot-accessor for subclass misses obsoleted superclass
-
- (defclass super ()
- ((x :initform 0 :accessor x-of)))
- (defclass sub (super) ())
-
- (defmethod shared-initialize :after ((i super) slots &rest init)
- (incf (x-of i)))
-
- (defvar *super* (make-instance 'super))
- (defvar *sub* (make-instance 'sub))
-
- (x-of *super*) ; => 1 ...ok
- (x-of *sub*) ; => 1 ...ok
-
- (make-instances-obsolete 'super)
-
- (x-of *sub*) ; => 1 ...ooops!
- (x-of *super*) ; => 2 ...ok
- (x-of *sub*) ; => 2 ...got it now
-
- (make-instances-obsolete 'super)
-
- (x-of *sub*) ; => 2 ...ooops, i did it again...
- (slot-value *sub* 'x) ; => 3 ...ok but a bit late
+ (fixed in sbcl-0.9.7.9)
\ No newline at end of file
expected. (reported by Tim Daly Jr)
* fixed bug #391: complicated :TYPE intersections in slot
definitions no longer cause an error in PCL internals.
+ * fixed bug #392: plugged a hole in the obsolete-instance protocol.
* bug fix: FILE-STRING-LENGTH is now external-format sensitive,
returning the number of octets which would be written to the
file-stream. (thanks to Robert J. Macomber)
;; LAYOUT-CLOS-HASH-MAX by the doc string of that constant,
;; generated as strictly positive in RANDOM-LAYOUT-CLOS-HASH..)
;;
+ ;; [ CSR notes, several years later (2005-11-30) that the value 0 is
+ ;; special for these hash slots, indicating that the wrapper is
+ ;; obsolete. ]
+ ;;
;; KLUDGE: The fact that the slots here start at offset 1 is known
;; to the LAYOUT-CLOS-HASH function and to the LAYOUT-dumping code
;; in GENESIS.
;; They're declared as INDEX.. Or is this a hack to try to avoid
;; having to use bignum arithmetic? Or what? An explanation would be
;; nice.
+ ;;
+ ;; an explanation is provided in Kiczales and Rodriguez, "Efficient
+ ;; Method Dispatch in PCL", 1990. -- CSR, 2005-11-30
(1+ (random layout-clos-hash-max
(if (boundp '*layout-clos-hash-random-state*)
*layout-clos-hash-random-state*
;;; Mark LAYOUT as invalid. Setting DEPTHOID -1 helps cause unsafe
;;; structure type tests to fail. Remove class from all superclasses
;;; too (might not be registered, so might not be in subclasses of the
-;;; nominal superclasses.)
+;;; nominal superclasses.) We set the layout-clos-hash slots to 0 to
+;;; invalidate the wrappers for specialized dispatch functions, which
+;;; use those slots as indexes into tables.
(defun invalidate-layout (layout)
(declare (type layout layout))
(setf (layout-invalid layout) t
(layout-depthoid layout) -1)
+ (dotimes (i layout-clos-hash-length)
+ (setf (layout-clos-hash layout i) 0))
(let ((inherits (layout-inherits layout))
(classoid (layout-classoid layout)))
(modify-classoid classoid)
;; the target Lisp's (RANDOM-LAYOUT-CLOS-HASH) sequence
;; and show up as the CLOS-HASH value of some other
;; LAYOUT.
- ;;
- ;; FIXME: This expression here can generate a zero value,
- ;; and the CMU CL code goes out of its way to generate
- ;; strictly positive values (even though the field is
- ;; declared as an INDEX). Check that it's really OK to
- ;; have zero values in the CLOS-HASH slots.
- (hash-value (mod (logxor (logand (random-layout-clos-hash) 15253)
- (logandc2 (random-layout-clos-hash) 15253)
- 1)
- ;; (The MOD here is defensive programming
- ;; to make sure we never write an
- ;; out-of-range value even if some joker
- ;; sets LAYOUT-CLOS-HASH-MAX to other
- ;; than 2^n-1 at some time in the
- ;; future.)
- (1+ sb!kernel:layout-clos-hash-max))))
+ (hash-value
+ (1+ (mod (logxor (logand (random-layout-clos-hash) 15253)
+ (logandc2 (random-layout-clos-hash) 15253)
+ 1)
+ ;; (The MOD here is defensive programming
+ ;; to make sure we never write an
+ ;; out-of-range value even if some joker
+ ;; sets LAYOUT-CLOS-HASH-MAX to other
+ ;; than 2^n-1 at some time in the
+ ;; future.)
+ sb!kernel:layout-clos-hash-max))))
(write-wordindexed result
(+ i sb!vm:instance-slots-offset 1)
(make-fixnum-descriptor hash-value))))
(in-package "SB-PCL")
\f
+;;; Ye olde CMUCL comment follows, but it seems likely that the paper
+;;; that would be inserted would resemble Kiczales and Rodruigez,
+;;; Efficient Method Dispatch in PCL, ACM 1990. Some of the details
+;;; changed between that paper and "May Day PCL" of 1992; some other
+;;; details have changed since, but reading that paper gives the broad
+;;; idea.
+;;;
;;; The caching algorithm implemented:
;;;
;;; << put a paper here >>
(slot-boundp *obsoleted* 'a)
(assert (= *obsoleted-counter* 1))
+;;; yet another MAKE-INSTANCES-OBSOLETE test, this time from Nikodemus
+;;; Siivola. Not all methods for accessing slots are created equal...
+(defclass yet-another-obsoletion-super () ((obs :accessor obs-of :initform 0)))
+(defclass yet-another-obsoletion-sub (yet-another-obsoletion-super) ())
+(defmethod shared-initialize :after ((i yet-another-obsoletion-super)
+ slots &rest init)
+ (incf (obs-of i)))
+
+(defvar *yao-super* (make-instance 'yet-another-obsoletion-super))
+(defvar *yao-sub* (make-instance 'yet-another-obsoletion-sub))
+
+(assert (= (obs-of *yao-super*) 1))
+(assert (= (obs-of *yao-sub*) 1))
+(make-instances-obsolete 'yet-another-obsoletion-super)
+(assert (= (obs-of *yao-sub*) 2))
+(assert (= (obs-of *yao-super*) 2))
+(make-instances-obsolete 'yet-another-obsoletion-super)
+(assert (= (obs-of *yao-super*) 3))
+(assert (= (obs-of *yao-sub*) 3))
+(assert (= (slot-value *yao-super* 'obs) 3))
+(assert (= (slot-value *yao-sub* 'obs) 3))
+
;;; shared -> local slot transfers of inherited slots, reported by
;;; Bruno Haible
(let (i)
;;; checkins which aren't released. (And occasionally for internal
;;; versions, especially for internal versions off the main CVS
;;; branch, it gets hairier, e.g. "0.pre7.14.flaky4.13".)
-"0.9.7.8"
+"0.9.7.9"
projects / sbcl.git / commitdiff