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From: knudsen@cbnewsd.ATT.COM (michael.j.knudsen)
Newsgroups: comp.lang.c
Subject: Re: is this broken or what?
Summary: Unsigneds never WHAT?
Message-ID: <12980@cbnewsd.ATT.COM>
Date: 31 Jan 90 18:21:53 GMT
References: <28941@amdcad.AMD.COM> <578@idacrd.UUCP> <1093@sdrc.UUCP>
Organization: AT&T Bell Laboratories
Lines: 15

In article <1093@sdrc.UUCP>, scjones@sdrc.UUCP (Larry Jones) writes:
> i-- also overflows), but not if i is unsigned (since unsigned
> arithmetic never overflows).

Excuse me -- one of us needs either a more reliable drugs supplier,
or a newer dictionary.  Unsigned arithmetic certainly can overflow--
it just gives you twice the headroom before it happens.
Doing i-- where i==0 will give a big surprise.
So will adding two positive numbers big enuf to wrap around.
Is this behavior not labeled "overflow"?  Correct me if I'm
wrong about this.
-- 
Mike Knudsen  knudsen@ihlpl.att.com   (708)-713-5134
"Round and round the while() loop goes;
        Whether it stops," Turing says, "no one knows."