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Date:	Sat, 04 May 2002 17:59:06 +0300
From:	"Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
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To:	Martin Steuer <martinSteuer AT gmx DOT de>
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In-reply-to:	<5.0.2.1.2.20020504135729.009e3690@pop.gmx.net> (message from
	Martin Steuer on Sat, 04 May 2002 14:04:32 +0200)
Subject:	Re: Can double negations get optimized out?
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> Date: Sat, 04 May 2002 14:04:32 +0200
> From: Martin Steuer <martinSteuer AT gmx DOT de>
> 
> [...]
> int a,b;
> scanf("%d",&a);
> b = !!a;
> [...]
> 
> I want to be sure that b can only be 1 or 0. Do i have to worry that this 
> is optimized out by a compiler?

Yes, you should worry.  What you want to say should be coded like
this:

	b = a != 0;

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