On Mon, 01 Oct 2012 07:20:49 +0000
bugzilla-daemon@freedesktop.org wrote:

> https://bugs.freedesktop.org/show_bug.cgi?id=43405
> 
> --- Comment #13 from Andreas Boll <andreas.boll.dev@gmail.com> ---
> (In reply to comment #12)
> 
> Can you try git clean -fdx before autogen?
> 
Before I got your message, I ran 
make -C src/glsl glsl_lexer.cc
which generated the file
After that, it built properly.
I'm still getting the same snow display.  I suspect it's an interaction with
the Squeeze X stack, since I didn't get this with Precise (which has its own
problems...)
I hope to try later when I've updated to the backports.org X server.