CC-mode problems

CC-mode problems

[Michael Welsh Duggan]

Every now and then I get indentation problems with cc-mode (c and c++).
(To be specific, on trunk.)  These problems are erratic and hard to
reproduce.  Usually saving and re-loading the file in question will fix
the problem, so recreating the problems requires not just a given file,
but also some subset of the sequence of events that lead to the problem.
The nature of the problems (indenting to wrong location, errors about a
cons being used when an integer is expected) leads me to believe the
actual bug(s) causing these are very subtle, and likely due to small
problems in the various caching mechanisms that have been added to make
cc-mode acceptably fast.

These problems, when they occur, can be very frustrating.  One of my
colleagues got so frustrated when things didn't indent properly that he
downgraded to Emacs 23.  The problem is: how to debug a problem (or
provide enough information to debug a problem) that is so difficult to
create on demand?  Perhaps cc-mode needs a way to cache all events in a
buffer in a re-playable manner.  Such a cache would be, of course, off by
default.

In any event, I don't like the fact that situations can arise in the
cc-mode in the released version of emacs that cause a person to reload
the buffer in order to re-achieve a stable state.  And I want to help
fix that fact.  Are there any suggestions?

-- 
Michael Welsh Duggan
(md5i@md5i.com)