bug#5786: new cc-mode <>-matching barfs in complex case

[Chong Yidong]

> Note: Although the trace below is from Emacs 22, I'm using cc-mode from
> HEAD. It doesn't affect the bug.
>
> cc-mode seems to barf in certain cases on files with lots of template
> brackets. I can't quite figure out what's wrong with it: the testcase
> below is about as small as I could make it.
>
> To reproduce: load the following file in c++-mode, position point at
> line 3, column 6 (just after the "/*"), and press space. It's
> important not to scroll around the buffer first. You'll see a
> backtrace

I can't reproduce the bug using emacs-23 branch (nor with the 23.1.95
pretest), starting from `emacs -Q'.

Daniel, could you please check if a 23.1.95 build from
ftp://alpha.gnu.org/gnu/emacs/pretest/ has this problem?

If so, please provide an even more exact recipe, sending the test file
as an attachement and providing precise steps starting from `emacs -Q'.