font-lock-mode causes paren-matching to go haywire in c++-mode

[Benjamin Rutt]

Recipe for reproducing the bug:

1) In current CVS head, put the following C++ code in a buffer called
bug.cpp (cut between the ----- lines):

-----------------------------------------------------------------------------
int StormIndexingClient::chooseTable()
{
    int idx = -1;
    if ((idx < 1) ||
        (idx > (int)len)) {
        fprintf(stderr, "ERROR:  invalid input %s\n", line);
    }
    idx--;
    return idx;
}
-----------------------------------------------------------------------------

2) run emacs -q bug.cpp, and verify you're in c++-mode
3) type M-x font-lock-mode RET
4) put cursor on line 5 of the resulting buffer (line numbering
   starting with 1)
5) place point on the '(' character at the beginning of the "(idx > ..." 
   expression  
6) press C-M-n...instead of getting placed on the matching paren, you get 
   placed on the '>' character.

Another way to exhibit the bug is use M-x show-paren-mode RET and
place the point on the opening ( of line 5.  It will show a faulty
matching end-paren.

I've tried to edebug this but the code ends up calling `scan-lists'
which is a primitive, so the bug must be down there.

Thanks,
Benjamin Rutt

In GNU Emacs 21.3.50.1 (i686-pc-linux-gnu, X toolkit, Xaw3d scroll bars)
 of 2004-03-11 on akron.bmi.ohio-state.edu
configured using `configure '--with-gif' '--with-jpeg' '--with-png' 
'--with-tiff' '--with-xpm' '--with-x' '--with-toolkit-scroll-bars' 
'--with-x-toolkit=yes' '--prefix=/scratch/rutt/local' 'CC=gcc''

Important settings:
  value of $LC_ALL: C
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_US.UTF-8
  locale-coding-system: nil
  default-enable-multibyte-characters: t

Major mode: C++

Minor modes in effect:
  mouse-wheel-mode: t
  menu-bar-mode: t
  font-lock-mode: t
  unify-8859-on-encoding-mode: t
  line-number-mode: t
  abbrev-mode: t

Recent input:
C-n M-x f o n t - l o c <tab> m o <tab> <return> C-n 
C-n C-n C-f C-u C-u C-f C-f C-u C-b C-f C-M-n C-M-p 
C-f C-u C-f C-u C-f C-M-p C-M-n C-b C-b C-b C-b C-b 
C-b C-b C-b C-b C-b C-b C-b C-b C-b C-b C-b C-M-n C-M-p 
C-M-n C-M-p C-M-n M-x s h o w - p a r <tab> C-g C-u 
C-b C-b C-b C-M-n C-M-p C-u C-p C-u C-p C-a M-x r e 
p o <tab> r <tab> <return>

Recent messages:
(./emacs -q /home/rutt/bug.cpp)
Loading tooltip...done
Loading image...done
Loading cc-mode...done
Loading font-lock...done
Loading jit-lock...done
Quit
Making completion list...
Loading help-mode...done
Loading emacsbug...done