Merge trivially safe differences from standalone CC-mode.

* lisp/progmodes/cc-mode.el (c-initialize-cc-mode): Don't quote a symbol
just to then pass it to `symbol-value'.
(prog-mode): Provide fallback definition, if needed.
* lisp/progmodes/cc-langs.el: Always load `cl'.  Don't load `cl-lib'.
Remove "cl-" prefix accordingly.
* lisp/progmodes/cc-fonts.el (c-font-lock-invalid-string): Use integerp or
characterp depending on the type of characters.
(c-font-lock-enum-tail): Remove unused var `start'.
* lisp/progmodes/cc-engine.el: Load CL at compile-time.
(c-declare-lang-variables): Use mapcan.
(c-append-to-state-cache): Remove unused var `ce+1'.
(c-parse-state-state): Make buffer-local.
(c-ssb-lit-begin): Remove unused var `pps-end-pos'.
(c-just-after-func-arglist-p): Remove unused var `end'.
* lisp/progmodes/cc-defs.el: Load cc-fix if delete-dups is undefined.
(c-<-as-paren-syntax, c->-as-paren-syntax): Move definition earlier.
(c-make-keywords-re): Use delete-dups.
(c-get-current-file): Avoid file-name-base.
* lisp/progmodes/cc-cmds.el (c-electric-lt-gt): Remove unused var
`close-paren-inserted'.
* lisp/progmodes/cc-awk.el (c-forward-sws): Remove unused declaration.

lisp/ChangeLog

@@ -1,5 +1,28 @@
 2014-10-04  Stefan Monnier  <monnier@iro.umontreal.ca>
 
+	Merge trivially safe differences from standalone CC-mode.
+	* progmodes/cc-mode.el (c-initialize-cc-mode): Don't quote a symbol
+	just to then pass it to `symbol-value'.
+	(prog-mode): Provide fallback definition, if needed.
+	* progmodes/cc-langs.el: Always load `cl'.  Don't load `cl-lib'.
+	Remove "cl-" prefix accordingly.
+	* progmodes/cc-fonts.el (c-font-lock-invalid-string): Use integerp or
+	characterp depending on the type of characters.
+	(c-font-lock-enum-tail): Remove unused var `start'.
+	* progmodes/cc-engine.el: Load CL at compile-time.
+	(c-declare-lang-variables): Use mapcan.
+	(c-append-to-state-cache): Remove unused var `ce+1'.
+	(c-parse-state-state): Make buffer-local.
+	(c-ssb-lit-begin): Remove unused var `pps-end-pos'.
+	(c-just-after-func-arglist-p): Remove unused var `end'.
+	* progmodes/cc-defs.el: Load cc-fix if delete-dups is undefined.
+	(c-<-as-paren-syntax, c->-as-paren-syntax): Move definition earlier.
+	(c-make-keywords-re): Use delete-dups.
+	(c-get-current-file): Avoid file-name-base.
+	* progmodes/cc-cmds.el (c-electric-lt-gt): Remove unused var
+	`close-paren-inserted'.
+	* progmodes/cc-awk.el (c-forward-sws): Remove unused declaration.
+
 	* progmodes/python.el: Avoid building unneeded markers.
 	(python-font-lock-keywords, python-indent-dedent-line)
 	(python-fill-paren, python-shell-completion-complete-or-indent):

lisp/progmodes/cc-awk.el

@@ -61,7 +61,6 @@
 (cc-bytecomp-defun c-backward-token-1)
 (cc-bytecomp-defun c-beginning-of-statement-1)
 (cc-bytecomp-defun c-backward-sws)
-(cc-bytecomp-defun c-forward-sws)
 
 (defvar awk-mode-syntax-table
   (let ((st (make-syntax-table)))

lisp/progmodes/cc-cmds.el

@@ -1090,7 +1090,7 @@ numeric argument is supplied, or the point is inside a literal."
 
   (interactive "*P")
   (let ((c-echo-syntactic-information-p nil)
-	final-pos close-paren-inserted found-delim case-fold-search)
+	final-pos found-delim case-fold-search)
 
     (self-insert-command (prefix-numeric-value arg))
     (setq final-pos (point))

lisp/progmodes/cc-defs.el

@@ -86,6 +86,11 @@
 	       font-lock-keywords)))
       (cc-load "cc-fix")))
 
+;; XEmacs 21.4 doesn't have `delete-dups'.
+(eval-and-compile
+  (if (and (not (fboundp 'delete-dups))
+	   (not (featurep 'cc-fix)))
+      (cc-load "cc-fix")))
 
 ;;; Variables also used at compile time.
 
@@ -913,6 +918,12 @@ MODE is either a mode symbol or a list of mode symbols."
 			       (cc-bytecomp-fboundp 'delete-extent)
 			       (cc-bytecomp-fboundp 'map-extents))))
 
+(defconst c-<-as-paren-syntax '(4 . ?>))
+(put 'c-<-as-paren-syntax 'syntax-table c-<-as-paren-syntax)
+
+(defconst c->-as-paren-syntax '(5 . ?<))
+(put 'c->-as-paren-syntax 'syntax-table c->-as-paren-syntax)
+
 ;; `c-put-char-property' is complex enough in XEmacs and Emacs < 21 to
 ;; make it a function.
 (defalias 'c-put-char-property-fun
@@ -1188,9 +1199,6 @@ been put there by c-put-char-property.  POINT remains unchanged."
     (if (< (point) start)
 	(goto-char (point-max)))))
 
-(defconst c-<-as-paren-syntax '(4 . ?>))
-(put 'c-<-as-paren-syntax 'syntax-table c-<-as-paren-syntax)
-
 (defsubst c-mark-<-as-paren (pos)
   ;; Mark the "<" character at POS as a template opener using the
   ;; `syntax-table' property via the `category' property.
@@ -1201,9 +1209,6 @@ been put there by c-put-char-property.  POINT remains unchanged."
   ;; cheaply.  We use this, for instance, in `c-parse-state'.
   (c-put-char-property pos 'category 'c-<-as-paren-syntax))
 
-(defconst c->-as-paren-syntax '(5 . ?<))
-(put 'c->-as-paren-syntax 'syntax-table c->-as-paren-syntax)
-
 (defsubst c-mark->-as-paren (pos)
   ;; Mark the ">" character at POS as an sexp list closer using the
   ;; syntax-table property.
@@ -1419,8 +1424,8 @@ Notably, null elements in LIST are ignored."
 
 (defun c-make-keywords-re (adorn list &optional mode)
   "Make a regexp that matches all the strings the list.
-Duplicates and nil elements in the list are removed.  The resulting
-regexp may contain zero or more submatch expressions.
+Duplicates and nil elements in the list are removed.  The
+resulting regexp may contain zero or more submatch expressions.
 
 If ADORN is t there will be at least one submatch and the first
 surrounds the matched alternative, and the regexp will also not match
@@ -1438,11 +1443,7 @@ The optional MODE specifies the language to get `c-nonsymbol-key' from
 when it's needed.  The default is the current language taken from
 `c-buffer-is-cc-mode'."
 
-  (let (unique)
-    (dolist (elt list)
-      (unless (member elt unique)
-	(push elt unique)))
-    (setq list (delete nil unique)))
+  (setq list (delete nil (delete-dups list)))
   (if list
       (let (re)
 
@@ -1638,13 +1639,13 @@ non-nil, a caret is prepended to invert the set."
 		  "support for the `syntax-table' text property "
 		  "is required.")))
 
-	;; Find out if generic comment delimiters work.
+	;; Find out if "\\s!" (generic comment delimiters) work.
 	(c-safe
 	  (modify-syntax-entry ?x "!")
 	  (if (string-match "\\s!" "x")
 	      (setq list (cons 'gen-comment-delim list))))
 
-	;; Find out if generic string delimiters work.
+	;; Find out if "\\s|" (generic string delimiters) work.
 	(c-safe
 	  (modify-syntax-entry ?x "|")
 	  (if (string-match "\\s|" "x")
@@ -1691,7 +1692,8 @@ non-nil, a caret is prepended to invert the set."
       (kill-buffer buf))
 
     ;; See if `parse-partial-sexp' returns the eighth element.
-    (if (c-safe (>= (length (save-excursion (parse-partial-sexp (point) (point))))
+    (if (c-safe (>= (length (save-excursion
+			      (parse-partial-sexp (point) (point))))
 		    10))
 	(setq list (cons 'pps-extended-state list))
       (error (concat
@@ -1707,9 +1709,8 @@ might be present:
 
 '8-bit              8 bit syntax entry flags (XEmacs style).
 '1-bit              1 bit syntax entry flags (Emacs style).
-'argumentative-bod-function         beginning-of-defun passes ARG through
-                    to a non-null beginning-of-defun-function.  It is assumed
-		    the end-of-defun does the same thing.
+'argumentative-bod-function	    beginning-of-defun and end-of-defun pass
+		    ARG through to beginning/end-of-defun-function.
 'syntax-properties  It works to override the syntax for specific characters
 		    in the buffer with the 'syntax-table property.  It's
 		    always set - CC Mode no longer works in emacsen without
@@ -1803,18 +1804,18 @@ system."
     (error "Unknown base mode `%s'" base-mode))
   (put mode 'c-fallback-mode base-mode))
 
-(defvar c-lang-constants (make-vector 151 0)
-  "Obarray used as a cache to keep track of the language constants.
-The constants stored are those defined by `c-lang-defconst' and the values
-computed by `c-lang-const'.  It's mostly used at compile time but it's not
-stored in compiled files.
+(defvar c-lang-constants (make-vector 151 0))
+;;   Obarray used as a cache to keep track of the language constants.
+;; The constants stored are those defined by `c-lang-defconst' and the values
+;; computed by `c-lang-const'.  It's mostly used at compile time but it's not
+;; stored in compiled files.
 
-The obarray contains all the language constants as symbols.  The
-value cells hold the evaluated values as alists where each car is
-the mode name symbol and the corresponding cdr is the evaluated
-value in that mode.  The property lists hold the source definitions
-and other miscellaneous data.  The obarray might also contain
-various other symbols, but those don't have any variable bindings.")
+;; The obarray contains all the language constants as symbols.  The
+;; value cells hold the evaluated values as alists where each car is
+;; the mode name symbol and the corresponding cdr is the evaluated
+;; value in that mode.  The property lists hold the source definitions
+;; and other miscellaneous data.  The obarray might also contain
+;; various other symbols, but those don't have any variable bindings.
 
 (defvar c-lang-const-expansion nil)
 
@@ -1831,7 +1832,9 @@ various other symbols, but those don't have any variable bindings.")
 	       (t
 		;; Being evaluated interactively.
 		(buffer-file-name)))))
-    (and file (file-name-base file))))
+    (and file
+	 (file-name-sans-extension
+	  (file-name-nondirectory file)))))
 
 (defmacro c-lang-defconst-eval-immediately (form)
   "Can be used inside a VAL in `c-lang-defconst' to evaluate FORM

lisp/progmodes/cc-fonts.el

@@ -366,39 +366,7 @@
 	      (parse-sexp-lookup-properties
 	       (cc-eval-when-compile
 		 (boundp 'parse-sexp-lookup-properties))))
-
-	  ;; (while (re-search-forward ,regexp limit t)
-	  ;;   (unless (progn
-	  ;; 	      (goto-char (match-beginning 0))
-	  ;; 	      (c-skip-comments-and-strings limit))
-	  ;;     (goto-char (match-end 0))
-	  ;;     ,@(mapcar
-	  ;; 	 (lambda (highlight)
-	  ;; 	   (if (integerp (car highlight))
-	  ;; 	       (progn
-	  ;; 		 (unless (eq (nth 2 highlight) t)
-	  ;; 		   (error
-	  ;; 		    "The override flag must currently be t in %s"
-	  ;; 		    highlight))
-	  ;; 		 (when (nth 3 highlight)
-	  ;; 		   (error
-	  ;; 		    "The laxmatch flag may currently not be set in %s"
-	  ;; 		    highlight))
-	  ;; 		 `(save-match-data
-	  ;; 		    (c-put-font-lock-face
-	  ;; 		     (match-beginning ,(car highlight))
-	  ;; 		     (match-end ,(car highlight))
-	  ;; 		     ,(elt highlight 1))))
-	  ;; 	     (when (nth 3 highlight)
-	  ;; 	       (error "Match highlights currently not supported in %s"
-	  ;; 		      highlight))
-	  ;; 	     `(progn
-	  ;; 		,(nth 1 highlight)
-	  ;; 		(save-match-data ,(car highlight))
-	  ;; 		,(nth 2 highlight))))
-	  ;; 	 highlights)))
 	  ,(c-make-font-lock-search-form regexp highlights))
-
 	nil)))
 
   (defun c-make-font-lock-BO-decl-search-function (regexp &rest highlights)
@@ -716,7 +684,11 @@ stuff.  Used on level 1 and higher."
   (let ((start (1- (point))))
     (save-excursion
       (and (eq (elt (parse-partial-sexp start (c-point 'eol)) 8) start)
-	   (if (integerp c-multiline-string-start-char)
+	   (if (if (eval-when-compile (integerp ?c))
+		   ;; Emacs
+		   (integerp c-multiline-string-start-char)
+		 ;; XEmacs
+		 (characterp c-multiline-string-start-char))
 	       ;; There's no multiline string start char before the
 	       ;; string, so newlines aren't allowed.
 	       (not (eq (char-before start) c-multiline-string-start-char))
@@ -1151,7 +1123,6 @@ casts and declarations are fontified.  Used on level 2 and higher."
       (when list
 	;; Jump past any initializer or function prototype to see if
 	;; there's a ',' to continue at.
-
 	(cond ((eq id-face 'font-lock-function-name-face)
 	       ;; Skip a parenthesized initializer (C++) or a function
 	       ;; prototype.
@@ -1219,8 +1190,8 @@ casts and declarations are fontified.  Used on level 2 and higher."
 	  ;; o - nil, if not in an arglist at all.  This includes the
 	  ;;   parenthesized condition which follows "if", "while", etc.
 	  context
-	  ;; The position of the next token after the closing paren of
-	  ;; the last detected cast.
+	  ;; A list of starting positions of possible type declarations, or of
+	  ;; the typedef preceding one, if any.
 	  last-cast-end
 	  ;; The result from `c-forward-decl-or-cast-1'.
 	  decl-or-cast
@@ -1564,9 +1535,7 @@ casts and declarations are fontified.  Used on level 2 and higher."
   ;; Note that this function won't attempt to fontify beyond the end of the
   ;; current enum block, if any.
   (let* ((paren-state (c-parse-state))
-	 (encl-pos (c-most-enclosing-brace paren-state))
-	 (start (point))
-	)
+	 (encl-pos (c-most-enclosing-brace paren-state)))
     (when (and
 	   encl-pos
 	   (eq (char-after encl-pos) ?\{)

lisp/progmodes/cc-guess.el

@@ -519,7 +519,8 @@ is called with one argument, the guessed style."
       (goto-char (point-min))
       (when (search-forward (concat "("
 				    (symbol-name (car needs-markers))
-				    " ") nil t)
+				    " ")
+                            nil t)
 	(move-end-of-line 1)
 	(comment-dwim nil)
 	(insert " Guessed value"))

lisp/progmodes/cc-langs.el

@@ -130,9 +130,7 @@
 
 
 ;; This file is not always loaded.  See note above.
-;; Except it is always loaded - see bug#17463.
-;;;(cc-external-require 'cl)
-(require 'cl-lib)
+(cc-external-require 'cl)
 
 
 ;;; Setup for the `c-lang-defvar' system.
@@ -253,14 +251,14 @@ the evaluated constant value at compile time."
     (unless xlate
       (setq xlate 'identity))
     (c-with-syntax-table (c-lang-const c-mode-syntax-table)
-      (cl-delete-duplicates
-       (cl-mapcan (lambda (opgroup)
+      (delete-duplicates
+       (mapcan (lambda (opgroup)
 		 (when (if (symbolp (car opgroup))
 			   (when (funcall opgroup-filter (car opgroup))
 			     (setq opgroup (cdr opgroup))
 			     t)
 			 t)
-		   (cl-mapcan (lambda (op)
+		   (mapcan (lambda (op)
 			     (when (funcall op-filter op)
 			       (let ((res (funcall xlate op)))
 				 (if (listp res) res (list res)))))
@@ -301,7 +299,8 @@ the evaluated constant value at compile time."
        ["Set Style..."                   c-set-style t]
        ["Show Current Style Name"        (message
 					  "Style Name: %s"
-					  c-indentation-style) t]
+					  c-indentation-style)
+                                         t]
        ["Guess Style from this Buffer"   c-guess-buffer-no-install t]
        ["Install the Last Guessed Style..." c-guess-install
 	(and c-guess-guessed-offsets-alist
@@ -1155,7 +1154,7 @@ operators."
 (c-lang-defconst c-all-op-syntax-tokens
   ;; List of all tokens in the punctuation and parenthesis syntax
   ;; classes.
-  t (cl-delete-duplicates (append (c-lang-const c-other-op-syntax-tokens)
+  t (delete-duplicates (append (c-lang-const c-other-op-syntax-tokens)
 			       (c-lang-const c-operator-list))
 		       :test 'string-equal))
 
@@ -1587,13 +1586,14 @@ properly."
 (c-lang-defvar c-syntactic-eol (c-lang-const c-syntactic-eol))
 
 
-;;; Defun functions
+;;; Defun handling.
 
-;; The Emacs variables beginning-of-defun-function and
-;; end-of-defun-function will be set so that commands like
-;; `mark-defun' and `narrow-to-defun' work right.  The key sequences
-;; C-M-a and C-M-e are, however, bound directly to the CC Mode
-;; functions, allowing optimization for large n.
+;; The Emacs variables beginning-of-defun-function and end-of-defun-function
+;; will be set so that commands like `mark-defun' and `narrow-to-defun' work
+;; right.  In older Emacsen, the key sequences C-M-a and C-M-e are, however,
+;; bound directly to the CC Mode functions, allowing optimisation for large n.
+;; From Emacs 23, this isn't necessary any more, since n is passed to the two
+;; functions.
 (c-lang-defconst beginning-of-defun-function
   "Function to which beginning-of-defun-function will be set."
   t 'c-beginning-of-defun
@@ -1754,7 +1754,7 @@ not the type face."
 (c-lang-defconst c-type-start-kwds
   ;; All keywords that can start a type (i.e. are either a type prefix
   ;; or a complete type).
-  t (cl-delete-duplicates (append (c-lang-const c-primitive-type-kwds)
+  t (delete-duplicates (append (c-lang-const c-primitive-type-kwds)
 			       (c-lang-const c-type-prefix-kwds)
 			       (c-lang-const c-type-modifier-kwds))
 		       :test 'string-equal))
@@ -1998,7 +1998,7 @@ one of `c-type-list-kwds', `c-ref-list-kwds',
   ;; something is a type or just some sort of macro in front of the
   ;; declaration.  They might be ambiguous with types or type
   ;; prefixes.
-  t (cl-delete-duplicates (append (c-lang-const c-class-decl-kwds)
+  t (delete-duplicates (append (c-lang-const c-class-decl-kwds)
 			       (c-lang-const c-brace-list-decl-kwds)
 			       (c-lang-const c-other-block-decl-kwds)
 			       (c-lang-const c-typedef-decl-kwds)
@@ -2192,7 +2192,7 @@ type identifiers separated by arbitrary tokens."
   pike '("array" "function" "int" "mapping" "multiset" "object" "program"))
 
 (c-lang-defconst c-paren-any-kwds
-  t (cl-delete-duplicates (append (c-lang-const c-paren-nontype-kwds)
+  t (delete-duplicates (append (c-lang-const c-paren-nontype-kwds)
 			       (c-lang-const c-paren-type-kwds))
 		       :test 'string-equal))
 
@@ -2218,7 +2218,7 @@ assumed to be set if this isn't nil."
 
 (c-lang-defconst c-<>-sexp-kwds
   ;; All keywords that can be followed by an angle bracket sexp.
-  t (cl-delete-duplicates (append (c-lang-const c-<>-type-kwds)
+  t (delete-duplicates (append (c-lang-const c-<>-type-kwds)
 			       (c-lang-const c-<>-arglist-kwds))
 		       :test 'string-equal))
 
@@ -2278,7 +2278,7 @@ Keywords here should also be in `c-block-stmt-1-kwds'."
 
 (c-lang-defconst c-block-stmt-kwds
   ;; Union of `c-block-stmt-1-kwds' and `c-block-stmt-2-kwds'.
-  t (cl-delete-duplicates (append (c-lang-const c-block-stmt-1-kwds)
+  t (delete-duplicates (append (c-lang-const c-block-stmt-1-kwds)
 			       (c-lang-const c-block-stmt-2-kwds))
 		       :test 'string-equal))
 
@@ -2382,7 +2382,7 @@ This construct is \"<keyword> <expression> :\"."
 (c-lang-defconst c-expr-kwds
   ;; Keywords that can occur anywhere in expressions.  Built from
   ;; `c-primary-expr-kwds' and all keyword operators in `c-operators'.
-  t (cl-delete-duplicates
+  t (delete-duplicates
      (append (c-lang-const c-primary-expr-kwds)
 	     (c-filter-ops (c-lang-const c-operator-list)
 			   t
@@ -2486,7 +2486,7 @@ Note that Java specific rules are currently applied to tell this from
 
 (c-lang-defconst c-keywords
   ;; All keywords as a list.
-  t (cl-delete-duplicates
+  t (delete-duplicates
      (c-lang-defconst-eval-immediately
       `(append ,@(mapcar (lambda (kwds-lang-const)
 			   `(c-lang-const ,kwds-lang-const))
@@ -2826,7 +2826,7 @@ possible for good performance."
 (c-lang-defvar c-block-prefix-charset (c-lang-const c-block-prefix-charset))
 
 (c-lang-defconst c-type-decl-prefix-key
-  "Regexp matching the declarator operators that might precede the
+  "Regexp matching any declarator operator that might precede the
 identifier in a declaration, e.g. the \"*\" in \"char *argv\".  This
 regexp should match \"(\" if parentheses are valid in declarators.
 The end of the first submatch is taken as the end of the operator.
@@ -3025,7 +3025,8 @@ identifier or one of the keywords on `c-<>-type-kwds' or
 expression is considered to be a type."
   t (or (consp (c-lang-const c-<>-type-kwds))
 	(consp (c-lang-const c-<>-arglist-kwds)))
-  java t)
+  java t)	    ; 2008-10-19.  This is crude.  The syntax for java
+		    ; generics is not yet coded in CC Mode.
 (c-lang-defvar c-recognize-<>-arglists (c-lang-const c-recognize-<>-arglists))
 
 (c-lang-defconst c-enums-contain-decls
@@ -3249,7 +3250,7 @@ accomplish that conveniently."
 			     ;; `c-lang-const' will expand to the evaluated
 			     ;; constant immediately in `macroexpand-all'
 			     ;; below.
-			      (cl-mapcan
+			      (mapcan
 			       (lambda (init)
 				 `(current-var ',(car init)
 				   ,(car init) ,(macroexpand-all

lisp/progmodes/cc-menus.el

@@ -361,7 +361,7 @@ Example:
 	    p (1+ p))
       (cond
        ;; Is CHAR part of a objc token?
-       ((and (not inargvar)     ; Ignore if CHAR is part of an argument variable.
+       ((and (not inargvar)   ; Ignore if CHAR is part of an argument variable.
 	     (eq 0 betweenparen) ; Ignore if CHAR is in parentheses.
 	     (or (and (<= ?a char) (<= char ?z))
 		 (and (<= ?A char) (<= char ?Z))

lisp/progmodes/cc-mode.el

@@ -185,8 +185,7 @@ control).  See \"cc-mode.el\" for more info."
 	    (run-hooks 'c-initialization-hook)
 	    ;; Fix obsolete variables.
 	    (if (boundp 'c-comment-continuation-stars)
-		(setq c-block-comment-prefix
-		      (symbol-value 'c-comment-continuation-stars)))
+		(setq c-block-comment-prefix c-comment-continuation-stars))
 	    (add-hook 'change-major-mode-hook 'c-leave-cc-mode-mode)
 	    (setq c-initialization-ok t)
 	    ;; Connect up with Emacs's electric-indent-mode, for >= Emacs 24.4
@@ -1322,6 +1321,7 @@ This function is called from `c-common-init', once per mode initialization."
 ;;;###autoload (add-to-list 'auto-mode-alist '("\\.i\\'" . c-mode))
 ;;;###autoload (add-to-list 'auto-mode-alist '("\\.ii\\'" . c++-mode))
 
+(unless (fboundp 'prog-mode) (defalias 'prog-mode 'fundamental-mode))
 
 ;;;###autoload
 (define-derived-mode c-mode prog-mode "C"

lisp/progmodes/cc-vars.el

@@ -275,13 +275,18 @@ nil."
   "*Controls the operation of the TAB key.
 If t, hitting TAB always just indents the current line.  If nil, hitting
 TAB indents the current line if point is at the left margin or in the
-line's indentation, otherwise it calls `c-insert-tab-function' to
-insert a `real' tab character.  If some other value (neither nil nor t),
-then inserts a tab only within literals (comments and strings), but
-always reindents the line.
+line's indentation, otherwise it inserts a `real' tab character \(see
+note\).	 If some other value (not nil or t), then tab is inserted only
+within literals \(comments and strings), but the line is always
+reindented.
 
-Note: the variable `c-comment-only-line-offset' also controls the
-indentation of lines containing only comments."
+Note: The value of `indent-tabs-mode' will determine whether a real
+tab character will be inserted, or the equivalent number of spaces.
+When inserting a tab, actually the function stored in the variable
+`c-insert-tab-function' is called.
+
+Note: indentation of lines containing only comments is also controlled
+by the `c-comment-only-line-offset' variable."
   :type '(radio
 	  (const :tag "TAB key always indents, never inserts TAB" t)
 	  (const :tag "TAB key indents in left margin, otherwise inserts TAB" nil)
@@ -920,7 +925,7 @@ Only currently supported behavior is `alignleft'."
 (defcustom c-special-indent-hook nil
   "*Hook for user defined special indentation adjustments.
 This hook gets called after each line is indented by the mode.  It is only
-called if `c-syntactic-indentation' is non-nil."
+called when `c-syntactic-indentation' is non-nil."
   :type 'hook
   :group 'c)
 
@@ -1689,7 +1694,8 @@ as designated in the variable `c-file-style'.")
 ;; It isn't possible to specify a doc-string without specifying an
 ;; initial value with `defvar', so the following two variables have been
 ;; given doc-strings by setting the property `variable-documentation'
-;; directly.  It's really good not to have an initial value for
+;; directly.  C-h v will read this documentation only for versions of GNU
+;; Emacs from 22.1.  It's really good not to have an initial value for
 ;; variables like these that always should be dynamically bound, so it's
 ;; worth the inconvenience.