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From: Peter Nielsen INF <pnielsen@ra.abo.fi>
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Subject: Re: Pb with LZW
To: john.aldridge@informatix.co.uk (John Aldridge)
Date: Thu, 25 Feb 1999 17:10:48 +0200 (EET)
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In-Reply-To: <3.0.6.32.19990225145849.00981710@mailserver> from "John Aldridge" at Feb 25, 99 02:58:49 pm
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>>Microsoft, on the other hand has redefined the standard and
>>the manual says that the result is "undefined" if all bits
>>are shifted out.
>
>Microsoft are right.  ANSI C says
>
>"If the value of the right operand is greater than or equal to the width in
>bits of the promoted left operand, the behaviour is undefined."

Hmm... I admit that I didn't check what ANSI C says since we were
interested in what the correct behaviour for C++ is. I think Bjarne
Stroustrup defines the result as zero in one of his books, but
correct me if I'm wrong. What does the 1998 ANSI C++ standard say?

Best regards,
	Peter
