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Message-ID: <42C41685.5FE33AEA@dessent.net>
Date: Thu, 30 Jun 2005 08:57:57 -0700
From: Brian Dessent <brian AT dessent DOT net>
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To: cygwin AT cygwin DOT com
Subject: Re: SV: Bug in printf ?
References: <SERRANOPL83mxMAKytt000002d1 AT SERRANO DOT CAM DOT ARTIMI DOT COM>
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Dave Korn wrote:

>   Absolutely, there's a rounding error of some sort.  Compare the difference
> when compiling the testcase with -mno-cygwin (i.e. using mingw maths lib):

Isn't this just a case of the Cygwin math library choosing "round to
even" and the MSVCRT/mingw library choosing "0.5 always rounds up"?  The
Goldberg paper covers this, and in fact it claims the IEEE standard
requires round to even for all results of addition, subtraction,
multiplication, and division.  Sooo, doesn't look like a bug at all to
me.

Brian

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