Subject: bug#14547: 24.3.1; line-break with pixel specification and word-wrap

From: Eli Zaretskii <[email-masked]>
Date: Mon, 03 Jun 2013 19:07:06 +0300

> Date: Mon, 3 Jun 2013 14:21:00 +0100
> From: E Sabof <[email-masked]>
> 
> If one executes the following in a graphical frame, the line will break:
> 
> (insert (propertize
>            "\n"
>            'display `(space :align-to (- right))
>            'face '(:underline t))
>           "\n")
> 
> (toggle-word-wrap 1)
> 
> If one makes the line one pixel shorter, it will work fine.
> 
> (insert (propertize
>            "\n"
>            'display `(space :align-to (- right (1)))
>            'face '(:underline t))
>           "\n")
> 
> (toggle-word-wrap 1)

Isn't that the same issue as discussed in this old bug:

  http://debbugs.gnu.org/cgi/bugreport.cgi?bug=9530

IOW, you cannot align-to the right margin, because this leaves no
place to display anything.