Re: How the long-lines "optimisation" breaks font locking.

[Eli Zaretskii]

> Date: Fri, 5 Aug 2022 22:50:07 +0300
> Cc: acm@muc.de, larsi@gnus.org, emacs-devel@gnu.org, gregory@heytings.org
> From: Dmitry Gutov <dgutov@yandex.ru>
> 
> On 05.08.2022 18:30, Eli Zaretskii wrote:
> >> The slow part I'm referring to is not in font-lock's code, nor in CC
> >> Mode's font-lock rules. So it can be "fixed" independently.
> > Then where is it?
> 
> Probably somewhere in the recent xdisp.c changes.

Very unlikely.  The recent changes in xdisp.c could not have possibly
slowed down the code there.

> Not in 'handle_fontified_prop', though.

That still leaves a lot of possibilities, so is not useful for making
any progress in this matter.