Subject: bug#12029: closed (Re: bug#12029: 24.1; cc-imenu-objc-function generates invalid imenu alist)

From: [email-masked] (GNU bug Tracking System)
Date: Sun, 29 Jul 2012 13:38:02 +0000

Your bug report

#12029: 24.1; cc-imenu-objc-function generates invalid imenu alist

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
12029: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=12029
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: bug#12029: 24.1; cc-imenu-objc-function generates invalid imenu alist
From: Leo <[email-masked]>
To: [email-masked]
Date: Sun, 29 Jul 2012 21:29:43 +0800
List-Id: <debbugs-submit.debbugs.gnu.org>

Fixed in emacs-24.

Subject: 24.1; cc-imenu-objc-function generates invalid imenu alist
From: Leo <[email-masked]>
To: [email-masked]
Date: Mon, 23 Jul 2012 13:40:46 +0800
List-Id: <debbugs-submit.debbugs.gnu.org>

1. Open the attached file t.m
2. Move point to be on @interface
3. M-x imenu

,----[ Backtrace ]
| Debugger entered--Lisp error: (wrong-type-argument stringp nil)
|   string-match("\\`@interface\\'" nil)
|   (if (string-match re (car x)) (throw (quote found) (car x)))
|   (while --cl-dolist-temp-- (setq x (car --cl-dolist-temp--)) (if (string-match re (car x)) (throw (quote found) (car x))) (setq --cl-dolist-temp-- (cdr --cl-dolist-temp--)))
|   (let ((--cl-dolist-temp-- completions) x) (while --cl-dolist-temp-- (setq x (car --cl-dolist-temp--)) (if (string-match re (car x)) (throw (quote found) (car x))) (setq --cl-dolist-temp-- (cdr --cl-dolist-temp--))))
|   (catch (quote --cl-block-nil--) (let ((--cl-dolist-temp-- completions) x) (while --cl-dolist-temp-- (setq x (car --cl-dolist-temp--)) (if (string-match re (car x)) (throw (quote found) (car x))) (setq --cl-dolist-temp-- (cdr --cl-dolist-temp--)))))
|   (cl-block-wrapper (catch (quote --cl-block-nil--) (let ((--cl-dolist-temp-- completions) x) (while --cl-dolist-temp-- (setq x (car --cl-dolist-temp--)) (if (string-match re (car x)) (throw (quote found) (car x))) (setq --cl-dolist-temp-- (cdr --cl-dolist-temp--))))))
|   (block nil (let ((--cl-dolist-temp-- completions) x) (while --cl-dolist-temp-- (setq x (car --cl-dolist-temp--)) (if (string-match re (car x)) (throw (quote found) (car x))) (setq --cl-dolist-temp-- (cdr --cl-dolist-temp--)))))
|   (dolist (x completions) (if (string-match re (car x)) (throw (quote found) (car x))))
|   (while --cl-dolist-temp-- (setq re (car --cl-dolist-temp--)) (dolist (x completions) (if (string-match re (car x)) (throw (quote found) (car x)))) (setq --cl-dolist-temp-- (cdr --cl-dolist-temp--)))
|   (let ((--cl-dolist-temp-- (list (concat "\\`" (regexp-quote guess) "\\'") (concat "\\`" (regexp-quote guess)) (concat (regexp-quote guess) "\\'") (regexp-quote guess))) re) (while --cl-dolist-temp-- (setq re (car --cl-dolist-temp--)) (dolist (x completions) (if (string-match re (car x)) (throw (quote found) (car x)))) (setq --cl-dolist-temp-- (cdr --cl-dolist-temp--))))
|   (catch (quote --cl-block-nil--) (let ((--cl-dolist-temp-- (list (concat "\\`" (regexp-quote guess) "\\'") (concat "\\`" (regexp-quote guess)) (concat (regexp-quote guess) "\\'") (regexp-quote guess))) re) (while --cl-dolist-temp-- (setq re (car --cl-dolist-temp--)) (dolist (x completions) (if (string-match re (car x)) (throw (quote found) (car x)))) (setq --cl-dolist-temp-- (cdr --cl-dolist-temp--)))))
|   (cl-block-wrapper (catch (quote --cl-block-nil--) (let ((--cl-dolist-temp-- (list (concat "\\`" (regexp-quote guess) "\\'") (concat "\\`" (regexp-quote guess)) (concat (regexp-quote guess) "\\'") (regexp-quote guess))) re) (while --cl-dolist-temp-- (setq re (car --cl-dolist-temp--)) (dolist (x completions) (if (string-match re (car x)) (throw (quote found) (car x)))) (setq --cl-dolist-temp-- (cdr --cl-dolist-temp--))))))
|   (block nil (let ((--cl-dolist-temp-- (list (concat "\\`" (regexp-quote guess) "\\'") (concat "\\`" (regexp-quote guess)) (concat (regexp-quote guess) "\\'") (regexp-quote guess))) re) (while --cl-dolist-temp-- (setq re (car --cl-dolist-temp--)) (dolist (x completions) (if (string-match re (car x)) (throw (quote found) (car x)))) (setq --cl-dolist-temp-- (cdr --cl-dolist-temp--)))))
|   (dolist (re (list (concat "\\`" (regexp-quote guess) "\\'") (concat "\\`" (regexp-quote guess)) (concat (regexp-quote guess) "\\'") (regexp-quote guess))) (dolist (x completions) (if (string-match re (car x)) (throw (quote found) (car x)))))
|   (if (assoc guess completions) guess (dolist (re (list (concat "\\`" (regexp-quote guess) "\\'") (concat "\\`" (regexp-quote guess)) (concat (regexp-quote guess) "\\'") (regexp-quote guess))) (dolist (x completions) (if (string-match re (car x)) (throw (quote found) (car x))))))
|   (let ((case-fold-search t)) (if (assoc guess completions) guess (dolist (re (list (concat "\\`" (regexp-quote guess) "\\'") (concat "\\`" (regexp-quote guess)) (concat (regexp-quote guess) "\\'") (regexp-quote guess))) (dolist (x completions) (if (string-match re (car x)) (throw (quote found) (car x)))))))
|   (catch (quote found) (let ((case-fold-search t)) (if (assoc guess completions) guess (dolist (re (list (concat "\\`" (regexp-quote guess) "\\'") (concat "\\`" (regexp-quote guess)) (concat (regexp-quote guess) "\\'") (regexp-quote guess))) (dolist (x completions) (if (string-match re (car x)) (throw (quote found) (car x))))))))
|   imenu-find-default(#("@interface" 0 10 (fontified t face font-lock-keyword-face)) (("*Rescan*" . -99) ("BarCodeViewController(Private)" ("@interface" . 1) ("-initReaderView" . 45)) (nil) ("BarCodeViewController" ("@implementation" . 76) ("-alertView:didDismissWithButtonIndex:" . 140))))
|   imenu--completion-buffer((("*Rescan*" . -99) ("BarCodeViewController(Private)" ("@interface" . 1) ("-initReaderView" . 45)) nil ("BarCodeViewController" ("@implementation" . 76) ("-alertView:didDismissWithButtonIndex:" . 140))) nil)
|   imenu-choose-buffer-index()
|   (list (imenu-choose-buffer-index))
|   call-interactively(imenu t nil)
|   execute-extended-command(nil)
|   call-interactively(execute-extended-command nil nil)
`----

This is due to cc-imenu-objc-function generates invalid imenu alist:

,----[ C-h v imenu--index-alist RET ]
| imenu--index-alist is a variable defined in `imenu.el'.
| Its value is nil
| 
|   Automatically becomes buffer-local when set in any fashion.
|   This variable is potentially risky when used as a file local variable.
| 
| Documentation:
| The buffer index alist computed for this buffer in Imenu.
| 
| Simple elements in the alist look like (INDEX-NAME . POSITION).
| POSITION is the buffer position of the item; to go to the item
| is simply to move point to that position.
| 
| Special elements look like (INDEX-NAME POSITION FUNCTION ARGUMENTS...).
| To "go to" a special element means applying FUNCTION
| to INDEX-NAME, POSITION, and the ARGUMENTS.
| 
| A nested sub-alist element looks like (INDEX-NAME SUB-ALIST).
| The function `imenu--subalist-p' tests an element and returns t
| if it is a sub-alist.
| 
| There is one simple element with negative POSITION; selecting that
| element recalculates the buffer's index alist.
| 
| [back]
`----

The following patch fixes this bug:

 lisp/progmodes/cc-menus.el |    8 ++------
 1 files changed, 2 insertions(+), 6 deletions(-)

	Modified lisp/progmodes/cc-menus.el
diff --git a/lisp/progmodes/cc-menus.el b/lisp/progmodes/cc-menus.el
index a53d65f6..76e3002a 100644
--- a/lisp/progmodes/cc-menus.el
+++ b/lisp/progmodes/cc-menus.el
@@ -399,14 +399,10 @@ (defun cc-imenu-objc-function ()
 		str2 "@protocol")))
 	(setq str (cc-imenu-objc-remove-white-space str))
 	(setq methodlist (cons (cons str2
-			      (match-beginning langnum))
+				     (match-beginning langnum))
 			       methodlist))
-	(setq toplist (cons nil (cons (cons str
-					  methodlist) toplist))
+	(setq toplist (cons (cons str methodlist) toplist)
 	      methodlist nil))))
-    ;;
-    (if (eq (car toplist) nil)
-	(setq toplist (cdr toplist)))
 
     ;; In this buffer, there is only one or zero @{interface|implementation|protocol}.
     (if (< classcount 2)