bug#23179: 25.0.92; Restore `M-,' to continue etags search

[Dmitry Gutov]

On 04/05/2016 08:43 AM, Anders Lindgren wrote:

> I gave it a test. The result looks good, and all matches are highlighted
> (regardless if the files are loaded or not). Unfortunately, it comes
> with a hefty overhead. The time increased from 7.5 s to 10.4 s.

That's too bad. Although the difference might be smaller with other 
major modes than CC Mode, where syntax-propertize, currently called 
anyway, is not a no-op.

> Also,
> the time is not reduced if you run it a second time, even if the files
> are present in Emacs buffers, indicating that font-lock
> is redone unnecessarily.

That's because we don't want to open a zillion buffers and keep them 
that way, and nobody has implemented find-file-delayed yet:

http://lists.gnu.org/archive/html/emacs-devel/2015-08/msg00076.html