Subject: Re: bug#13949: 24.4.1; `fill-paragraph' should not always put the buffer as modified

From: Dmitry Gutov <[email-masked]>
Date: Sun, 27 Mar 2016 18:28:22 +0300

On 03/27/2016 06:31 AM, Óscar Fuentes wrote:

> +  (when (and (not (string= h ""))
> +             (string= h (secure-hash 'md5 (current-buffer))))
> +    (set-buffer-modified-p nil)))

Hashes have collisions (and md5 is a bit famous for them). So in 
principle, I don't think using a hash is a good choice in this case.

Either way, you'd have to keep the original string around, to compare 
against if the hashes match.