bug#30937: In `comment-region', C-g doesn't work.

[Alan Mackenzie]

Hello, Eli.

On Sun, Mar 25, 2018 at 18:32:10 +0300, Eli Zaretskii wrote:
> > Date: Sun, 25 Mar 2018 14:28:55 +0000
> > From: Alan Mackenzie <acm@muc.de>

> > emacs-26.0.91 -Q
> > C-x C-f Any largish file.c
> > C-x h                 ; mark buffer.
> > C-c C-c               ; comment-region.

> > This is the sort of thing that can happen by accident.  Depending on the
> > size of the file.c and the speed of your machine, you've now got a long,
> > long wait.  C-g doesn't work.  This is a bug.

> C-g does work for me just fine in the above recipe.  Maybe it's
> platform dependent, and the problem happens only on X?

Yes, I've just tried it on X.  It works there (except it leaves point in
a suboptimal position: the starting point.  It should really leave point
after the last newly commented line when the quit happened).  It works
on emacs -nw, with the same proviso.

It doesn't work at all on a Linux tty.  Sorry I didn't try X before
reporting the bug.

-- 
Alan Mackenzie (Nuremberg, Germany).