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From: George Neuner <gneuner2@comcast.net>
Newsgroups: comp.compilers
Subject: Re: Compiler optimization and floating point operations
Date: Thu, 24 Oct 2013 15:51:08 -0400
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On Thu, 24 Oct 2013 07:41:12 -0400, George Neuner
<gneuner2@comcast.net> wrote:

>Floating point operations, in general, are not commutative: changing
>the order of evaluation of sub-expressions can change the results.

John replied:
>[I think you mean they're not associative.  I don't know any situations
>where a+b != b+a, but lots where a+(b+c) != (a+b)+c -John]

Yes, definitely "associative".  Thanks for the correction.
George