(isearch-multibyte-characters-flag): Deleted.

(isearch-mode): Do not bind isearch-multibyte-characters-flag and
isearch-input-method.
(isearch-printing-char): Use current-input-method instead of
isearch-input-method.
(isearch-message-prefix): Likewise.

lisp/isearch.el

@@ -369,9 +369,6 @@ Default value, nil, means edit the string instead."
 ;; Flag to indicate a yank occurred, so don't move the cursor.
 (defvar isearch-yank-flag nil)
 
-;; Flag to indicate that we are searching multibyte characaters.
-(defvar isearch-multibyte-characters-flag nil)
-
 ;;; A function to be called after each input character is processed.
 ;;; (It is not called after characters that exit the search.)
 ;;; It is only set from an optional argument to `isearch-mode'.
@@ -521,8 +518,6 @@ is treated as a regexp.  See \\[isearch-forward] for more info."
 	isearch-other-end nil
 	isearch-small-window nil
 	isearch-just-started t
-	isearch-multibyte-characters-flag nil
-	isearch-input-method nil
 
 	isearch-opoint (point)
 	search-ring-yank-pointer nil
@@ -1183,7 +1178,7 @@ Obsolete."
 (defun isearch-printing-char ()
   "Add this ordinary printing character to the search string and search."
   (interactive)
-  (if isearch-input-method
+  (if current-input-method
       (isearch-process-search-multibyte-characters (isearch-last-command-char))
     (isearch-process-search-char (isearch-last-command-char))))
 
@@ -1419,8 +1414,8 @@ If there is no completion possible, say so and continue searching."
 		   (if isearch-regexp "regexp " "")
 		   (if nonincremental "search" "I-search")
 		   (if isearch-forward "" " backward")
-		   (if isearch-input-method
-		       (concat " [" isearch-input-method-title "]: ")
+		   (if current-input-method
+		       (concat " [" current-input-method-title "]: ")
 		     ": ")
 		   )))
     (aset m 0 (upcase (aref m 0)))