zsh eats 100% CPU with completion in /

[Frank Terbeck <ft@xxxxxxxxxxxxxxxxxxx>]

The subject is not entirely correct.

Zsh eats 100% CPU on a colleague's laptop if you do this:
% cd /
% cd ..
% ./<tab>

Happens with the most recent CVS HEAD, too.
That's on linux (debian stable, actually).

The problem is reproducible on his machine. And it doesn't happen if
you do this:
% cd /
% ./<tab>

The 'cd ..' is required.

I cannot reproduce the problem on my system with exactly the same
configuration and with exactly the same zsh version. And I am in fact
using the very same OS (debian stable), too.

As you can imagine, I am quite puzzled and I don't know how to tackle
this.

Any hints or suggestions are highly welcome.

Regards, Frank