Re: cc-mode fontification feels random

[Alan Mackenzie]

Hello, Eli.

On Sun, Jun 06, 2021 at 14:57:35 +0300, Eli Zaretskii wrote:
> > Date: Sun, 6 Jun 2021 11:37:47 +0000
> > From: Alan Mackenzie <acm@muc.de>
> > Cc: emacs-devel@gnu.org

> > > FWIW, fontification is correct and consistent when I set 
> > > font-lock-support-mode to nil, so this really does look like another 
> > > case of getting unlucky with jit-lock block divisions.

> > Maybe an improvement might come from scanning the buffer for occurrences
> > of foo after foo has been recognised as a type and entered into the CC
> > Mode table.  That way, the lack of fontification on foo would be
> > temporary, at least provided your Emacs is configured to fontify
> > non-displayed bits of the buffer in the background (which it is by
> > default).

> > This might need enhanced support from jit-lock, such as some sort of
> > signal indicating a buffer has been completly fontified.  I haven't
> > thought this through, yet.

> AFAIR, the way to tell JIT font-lock that a chunk of text was already
> fontified is to set the 'fontified' property on that text.

Sorry, I was unclear.  I was thinking of a signal from jit-lock to the
major mode, indicating that background fontification had been completed.
CC Mode could react to this by fontifying all occurrences in the buffer
of "newly found" types.  Or something like that.

Or maybe the fontification could be done immediately after parsing a new
type.  This might be a bit sluggish, but it might be OK.

-- 
Alan Mackenzie (Nuremberg, Germany).