From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andreas Schwab <schwab@suse.de>
Subject: Re: MSEC_TO_JIFFIES is messed up...
Date: Wed, 12 May 2004 23:55:18 +0200
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Cc: Davide Libenzi <davidel@xmailserver.org>,
	Ingo Molnar <mingo@elte.hu>, Jeff Garzik <jgarzik@pobox.com>,
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To: "J. Bruce Fields" <bfields@fieldses.org>
In-Reply-To: <20040512213913.GA16658@fieldses.org> (J. Bruce Fields's
 message of "Wed, 12 May 2004 17:39:13 -0400")
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"J. Bruce Fields" <bfields@fieldses.org> writes:

> If gcc really optimizes that to just the identity function, then sure=
ly
> that's a gcc bug?  Multiplication is left-associative, so i * 1000 /
> 1000 =3D (i * 1000) / 1000, but (i * 1000) should be zero for any i
> divisible by i^(sizeof(int) - 12).

Signed integer overflow is undefined in C, so the compiler is allowed t=
o
assume it does not happen.

Andreas.

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Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux AG, Maxfeldstra=DFe 5, 90409 N=FCrnberg, Germany
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