bug#1949: comment-dwim freezes emacs while in css-mode

[xah lee]

To reproduce,

• start emacs with /Applications/Emacs.app/Contents/MacOS/Emacs -q

• create this file (contet between the dashes):

------------------------
@import "../../lang.css";

div.cmt {display:table; padding:1ex; background-color:#ffdab9}
span.cmt {background-color:#ffdab9}
----------------------

• name it “ff.css”. Now, open the file, M-x css-mode.

• Place your cursor in the blank line there, then M-x comment-dwim.

• Emacs seems to freeze. Type Ctrl+g to unfreeze.

This bug is reproducible when starting emacs with

  Xah
∑ http://xahlee.org/

☄

In GNU Emacs 22.2.1 (powerpc-apple-darwin8.11.0, Carbon Version 1.6.0)
 of 2008-04-05 on g5.tokyo.stp.isas.jaxa.jp
Windowing system distributor `Apple Inc.', version 10.4.11
configured using `configure  '--prefix=/Applications/Emacs.app/ 
Contents/Resources' '--with-carbon' '--without-x' '--libexecdir=/ 
Volumes/Emacs/Emacs.app/Contents/MacOS/libexec' 'CFLAGS=-Os -arch  
i386 -arch ppc -isysroot /Developer/SDKs/MacOSX10.4u.sdk -DUSE_ATSUI - 
DUSE_MAC_TSM''


Major mode: CSS

Minor modes in effect:
  encoded-kbd-mode: t
  command-frequency-autosave-mode: t
  command-frequency-mode: t
  yas/minor-mode: t
  desktop-save-mode: t
  recentf-mode: t
  show-paren-mode: t
  delete-selection-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t
  abbrev-mode: t