From a1a141e3a908f69368fe6faa54c4fd5439e5700e Mon Sep 17 00:00:00 2001
From: yamaoka <yamaoka>
Date: Thu, 4 Jul 2002 09:26:51 +0000
Subject: [PATCH] * dgnushack.el (byte-optimize-form-code-walker): Don't
 modify the function  definition if the bug has already
 gone; revert to the use of `defadvice'.

---
 ChangeLog         |    6 ++++++
 lisp/dgnushack.el |   34 +++++++++++++++++++---------------
 2 files changed, 25 insertions(+), 15 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 5bd2c01..1545a78 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2002-07-04  Katsumi Yamaoka  <yamaoka@jpl.org>
+
+	* lisp/dgnushack.el (byte-optimize-form-code-walker): Don't modify
+	the function definition if the bug has already gone; revert to the
+	use of `defadvice'.
+
 2002-07-03  Keiichi Suzuki  <keiichi@nanap.org>
 
 	* lisp/gnus-logic.el (gnus-advanced-index): Use luna based index
diff --git a/lisp/dgnushack.el b/lisp/dgnushack.el
index ea3d548..e3b3e53 100644
--- a/lisp/dgnushack.el
+++ b/lisp/dgnushack.el
@@ -124,14 +124,21 @@ to the specified name LIBRARY (a la calling `load' instead of `load-library')."
 	nil))
     (byte-compile 'locate-library)))
 
-(unless (fboundp 'si:byte-optimize-form-code-walker)
-  (byte-optimize-form nil);; Load `byte-opt' or `byte-optimize'.
-  (setq max-specpdl-size 3000)
-  (defalias 'si:byte-optimize-form-code-walker
-    (symbol-function 'byte-optimize-form-code-walker))
-  (defun byte-optimize-form-code-walker (form for-effect)
+(setq max-specpdl-size 3000)
+
+(when (equal
+       (cadr
+	(byte-optimize-form
+	 '(and
+	   (< 0 1)
+	   (message "The subform `(< 0 1)' should be optimized to `t'"))
+	 'for-effect))
+       '(< 0 1))
+  (defadvice byte-optimize-form-code-walker
+    (around fix-bug-in-and/or-forms (form for-effect) activate)
+    "Fix a bug in the optimizing and/or forms.
+It has already been fixed in XEmacs since 1999-12-06."
     (if (and for-effect (memq (car-safe form) '(and or)))
-	;; Fix bug in and/or forms.
 	(let ((fn (car form))
 	      (backwards (reverse (cdr form))))
 	  (while (and backwards
@@ -141,14 +148,11 @@ to the specified name LIBRARY (a la calling `load' instead of `load-library')."
 	  (if (and (cdr form) (null backwards))
 	      (byte-compile-log
 	       "  all subforms of %s called for effect; deleted" form))
-	  (if backwards
-	      (let ((head backwards))
-		(while (setq backwards (cdr backwards))
-		  (setcar backwards (byte-optimize-form (car backwards)
-							nil)))
-		(cons fn (nreverse head)))))
-      (si:byte-optimize-form-code-walker form for-effect)))
-  (byte-compile 'byte-optimize-form-code-walker))
+	  (when backwards
+	    (setcdr backwards
+		    (mapcar 'byte-optimize-form (cdr backwards))))
+	  (setq ad-return-value (cons fn (nreverse backwards))))
+      ad-do-it)))
 
 (condition-case nil
     (char-after)
-- 
1.7.10.4