Don't always require newcomment.

(imenu--generic-function): Call comment-normalize-vars
if we have a comment syntax.
Exit the loop if REGEXP matches the null string.
Test comment-start as well as comment-start-skip
when deciding whether to check for comments.

1 files changed, 12 insertions, 7 deletions

diff --git a/lisp/imenu.el b/lisp/imenu.el
index d20dc4bccb8..32dda9fd3c6 100644
--- a/lisp/imenu.el
+++ b/lisp/imenu.el
@@ -62,8 +62,6 @@
 
 ;;; Code:
 
-(require 'newcomment)
-
 (eval-when-compile (require 'cl))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -745,8 +743,8 @@ for modes which use `imenu--generic-function'.  If it is not set, but
 ;;;###autoload
 (make-variable-buffer-local 'imenu-case-fold-search)
 
-;; Originally "Built on some ideas that Erik Naggum <erik@naggum.no>
-;; once posted to comp.emacs" but since substantially re-written.
+;; This function can be called with quitting disabled,
+;; so it needs to be careful never to loop!
 (defun imenu--generic-function (patterns)
   "Return an index of the current buffer as an alist.
 
@@ -800,6 +798,9 @@ depending on PATTERNS."
     (unwind-protect                     ; for syntax table
         (save-match-data
           (set-syntax-table table)
+          (if (or comment-start comment-start-skip)
+              (comment-normalize-vars))
+
           ;; map over the elements of imenu-generic-expression
           ;; (typically functions, variables ...)
           (dolist (pat patterns)
@@ -812,12 +813,16 @@ depending on PATTERNS."
                   cs)
               ;; Go backwards for convenience of adding items in order.
               (goto-char (point-max))
-              (while (re-search-backward regexp nil t)
+              (while (and (re-search-backward regexp nil t)
+                          ;; Exit the loop if we get an empty match,
+                          ;; because it means a bad regexp was specified.
+                          (not (= (match-beginning 0) (match-end 0))))
                 (setq start (point))
                 (goto-char (match-end index))
                 (setq beg (match-beginning index))
-                (setq cs (and comment-start-skip
-                              (save-match-data (comment-beginning))))
+                (setq cs (and (or comment-start comment-start-skip)
+                              (save-match-data
+                                (comment-beginning))))
                 (if cs
                     (goto-char (min cs beg)) ; skip this one, it's in a comment
                   (goto-char beg)