Re: CC Mode troubles and Emacs 29

[Eli Zaretskii <eliz@gnu.org>]

> From: Po Lu <luangruo@yahoo.com>
> Cc: Alan Mackenzie <acm@muc.de>,  emacs-devel@gnu.org
> Date: Tue, 10 Jan 2023 09:05:36 +0800
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> >> Date: Mon, 9 Jan 2023 15:48:12 +0000
> >> Cc: Eli Zaretskii <eliz@gnu.org>, emacs-devel@gnu.org
> >> From: Alan Mackenzie <acm@muc.de>
> >> 
> >> On Mon, Jan 09, 2023 at 21:49:20 +0800, Po Lu wrote:
> >> > Eli Zaretskii <eliz@gnu.org> writes:
> >> 
> >> > > Is there a bug number for this issue? if so, could you please tell
> >> > > what it is?
> >> 
> >> One of the bugs is bug #59671.
> >
> > I see no user-facing problems with the recipe there.  It sounds like
> > you are discussing some internal feature of CC mode that potentially
> > misbehaves in that case.  Why should I, as a user, care?  More
> > importantly, why should I, as an Emacs maintainer, be worried due to
> > this problem, which Po Lu described as a "major regression"?  I don't
> > even see a regression, let alone a major one.  What did I miss?
> 
> That's just one bug of many.  If you look at the CC Mode bug tracker for
> November, you'll see a lot of bugs that boil down to this: after 25 to
> 60 minutes of editing in a buffer, the entire buffer is filled with
> green splotches (making fontification useless) and C Mode has to be
> re-enabled, because CC Mode keeps misrecognizing and fontifying
> identifiers as types.

If this is so, I find it strange that we don't have heaps of bug
reports about this in our bug tracker.  I doubt that anyone could
ignore the terrible misbehavior you describe, if indeed the
description is accurate and not exaggerated.

I guess we will have to wait till the pretest to see how bad that is
in practice.