From mboxrd@z Thu Jan  1 00:00:00 1970
From: "J. Bruce Fields" <bfields@fieldses.org>
Subject: Re: MSEC_TO_JIFFIES is messed up...
Date: Wed, 12 May 2004 18:07:33 -0400
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Cc: Davide Libenzi <davidel@xmailserver.org>, Ingo Molnar <mingo@elte.hu>,
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To: Andreas Schwab <schwab@suse.de>
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On Wed, May 12, 2004 at 11:55:18PM +0200, Andreas Schwab wrote:
> "J. Bruce Fields" <bfields@fieldses.org> writes:
> 
> > If gcc really optimizes that to just the identity function, then surely
> > that's a gcc bug?  Multiplication is left-associative, so i * 1000 /
> > 1000 = (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 to
> assume it does not happen.

Ugh, right, got it.--b.