Michael Welsh Duggan <mwd@cert.org> writes:

>>> There is generally no way to re-create it, so I've stopped reporting
>>> these.  I wish there were some way to record all actions in c-mode
>>> buffers such that they could be saved and re-played when this type of
>>> problem happens.  If there were some sort of debug flag I could turn
>>> on, I would turn it on by default and hopefully be able to catch some
>>> useful information.
>>
>> M-x c-toggle-parse-state-debug
>>
>> (or (c-toggle-parse-state-debug 1) in your .emacs).  Warning: variable
>> `c-debug-parse-state' is not buffer local.  I wrote this on 19th October
>> last year to help sort out the bug you reported a little earlier.  :-)
>
> I will turn this on.

Okay, I have something repeatable.  This is with an older checkout
("109494 dmantipov@yandex.ru-20120807112841-k0pyiinoxi2llcmu"), so I'm
updating my sources to see if this holds in the current bzr.  In the
meantime, here's a recipe that works in the above version.

1) emacs -Q
2) C-x C-f <attached-file>
3) M-x c-toggle-parse-state-debug RET
4) C-v until you get a state inconsistency message (10 times for me)

c-parse-state inconsistency at 9942: using cache: (9866 9516 5134 5090), from scratch: (9866 9516 (7654 . 9439) 5134 5090)
Old state:
(setq c-state-cache '(9516 5134 5090)  c-state-cache-good-pos 10231  c-state-nonlit-pos-cache '(15063 12049 9049 6049 3049)  c-state-nonlit-pos-cache-limit 15063  c-state-brace-pair-desert '(9516 . 9818)  c-state-point-min 1  c-state-point-min-lit-type nil  c-state-point-min-lit-start nil  c-state-min-scan-pos 1  c-state-old-cpp-beg nil  c-state-old-cpp-end nil)
c-parse-state inconsistency at 9942: using cache: (9866 9516 5134 5090), from scratch: (9866 9516 (7654 . 9439) 5134 5090)
Old state:
(setq c-state-cache '(9866 9516 5134 5090)  c-state-cache-good-pos 9867  c-state-nonlit-pos-cache '(15063 12049 9049 6049 3049)  c-state-nonlit-pos-cache-limit 15063  c-state-brace-pair-desert '(9516 . 9818)  c-state-point-min 1  c-state-point-min-lit-type nil  c-state-point-min-lit-start nil  c-state-min-scan-pos 1  c-state-old-cpp-beg nil  c-state-old-cpp-end nil)