Fix uninitialised variable warning

[Geoff Keating]

> Date: Sat, 12 Apr 2003 17:06:45 +0200
> From: Andreas Tobler <toa@pop.agri.ch>
> User-Agent: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.3) Gecko/20030312
> X-Accept-Language: en-us, en
> Cc: Geoff Keating <geoffk@geoffk.org>, gcc-patches@gcc.gnu.org
> X-OriginalArrivalTime: 12 Apr 2003 15:07:01.0890 (UTC) FILETIME=[2BDD6620:01C30105]
> 
> David Edelsohn wrote:
> > 	Andreas Tobler already proposed the fix:
> > 
> > http://gcc.gnu.org/ml/gcc-patches/2003-04/msg00803.html
> > 
> > but no one committed it.
> 
> rth did approve it, but at this time I was already asleep ;)
> And then this morning Geoff was faster.
> 
> Btw, out of curiosity, what's the difference between initializing with 
> -1 vs 0?

I picked -1 because I thought it would be better if the checksum was
unlikely to match if it wasn't ever initialised.

-- 
- Geoffrey Keating <geoffk@geoffk.org>