Jan Synacek <jsynacek@redhat.com> writes:

> Steps to reproduce:
> 1) C-x C-f foo.xml
> 2) M-x flyspell-mode
> 3) Then paste in the following:
> <?xml version="1.0" encoding="UTF-8"?>
> <Simulation>
>       <compare>
>         <data>fullprint1</data>
>       </compare>
>       <!-- <compare>
>         <data>fullprint2</data>
>       </compare> -->
> </Simulation>
> 4) Go to the line with fullprint2:
>    C-k C-k
> 5) Go to the line after fullprint1:
>    C-y
>    At this point, emacs hangs, eating all of my CPU.
>
> The tested version is the current upstream master (commit 61e83e9).

This looks like http://debbugs.gnu.org/16449.

Nico