bug#31557: 27.0.50; SES hangs on save when 'delete-trailing-whitespace' is in 'before-save-hook'

[Noam Postavsky]

Eli Zaretskii <eliz@gnu.org> writes:

> If my reading of the code is correct, it should infloop for every use
> case where region-modifiable-p returns nil.

Yes, agreed.

> Does the patch below look right?
>
> --- lisp/simple.el~0  2018-03-14 06:40:04.000000000 +0200
> +++ lisp/simple.el    2018-06-03 17:51:37.213490900 +0300
> @@ -667,8 +667,9 @@
>            (while (re-search-forward "\\s-$" end-marker t)
>              (skip-syntax-backward "-" (line-beginning-position))
>              (let ((b (point)) (e (match-end 0)))
> -              (when (region-modifiable-p b e)
> -                (delete-region b e)))))
> +              (if (region-modifiable-p b e)
> +                  (delete-region b e)
> +                (goto-char e)))))

Looks good to me.