Subject: bug#10652: 24.0.93; font-lock very slow for C++

From: Alan Mackenzie <[email-masked]>
Date: Fri, 16 Mar 2012 14:19:37 +0000

Hello, Yidong, Helmut.

On Sun, Feb 26, 2012 at 05:47:25PM +0800, Chong Yidong wrote:
> Helmut Eller <[email-masked]> writes:

> > Font lock is extremely slow in this file:

> > http://hg.openjdk.java.net/jdk7/jdk7/hotspot/raw-file/b92c45f2bc75/src/share/vm/runtime/globals.hpp

> > Download the file and open it with emacs -Q globals.hpp.  Then
> > scroll around in the file to see how slow it is.

> I got Emacs into an uninterruptible loop while scrolling through the
> buffer :-(

> Looks like a regression against Emacs 23's CC mode, which handles the
> file just fine.  Alan, could you investigate?  Thanks.

I've just committed revision #107615, which solves the slow scrolling
problem.  Typing "electric" characters (e.g. comma) into the buffer is
still slower than I'd like, but is tolerable.

I don't intend doing any more optimisation before the next pretest (or
release :-).

-- 
Alan Mackenzie (Nuremberg, Germany).