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Re: GCC beaten by ICC in stupid trig test!
On Wed, Mar 24, 2004 at 02:10:13PM -0500, Paul Koning wrote:
> Joe> Consider a, b, and c as single precision floating point values,
> Joe> and a=1, b=-1, c=1.2345e-8. (a+b)+c will compute as 1.2345e-8.
> Joe> a+(b+c) will return zero, as will (a+c)+b.
>
> I don't have a C standard, but my copy of Harbison & Steele says what
> I expected about parentheses: "Parentheses do not necessarily force a
> particular evaluation order".
This was true of K&R C, but I seem to recall that the standards committee
changed that. Any standards gurus out there care to comment?