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From:	Mike Marchywka <marchywka AT hotmail DOT com>
To:	Richard Stanton <stanton AT haas DOT berkeley DOT edu>,
	"cygwin AT cygwin DOT com" <cygwin AT cygwin DOT com>
Subject:	RE: cygwin gcc: Different numerical results in thread vs in main()
Date:	Mon, 4 Aug 2008 13:01:48 -0400
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> From: stanton AT haas DOT berkeley DOT edu
> To: marchywka AT hotmail DOT com; cygwin AT cygwin DOT com
> Date: Mon, 4 Aug 2008 09:40:36 -0700
> Subject: RE: cygwin gcc: Different numerical results in thread vs in main()
>
> 1) The result from the within thread calculation matches my Mac output (note that the Mac is also an Intel based machine, and I'm also using gcc there, albeit version 4.0.1, so clearly something is operating differently there). The main() result is different from the Mac output.
>

rant>
I would have replied 5 minutes sooner but I was waiting for hotmail to let me go to text
mode while an ad, probably composed by someone who doesn't know what a CPU is, show
me an animation of something.
/rant>

The only reason I point this out is that you can write indefinite precision math code but it will be slower. The compiler may generate much better code if you don't care about the last few bits. 
Definitely check the intel books on architecture and issues, not sure what to suggest on floating
point but maybe one of the standards groups discusses the issues.


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