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Re: complex arithmetic and signed zero?
On Wed, Oct 12, 2005 at 01:24:41PM -0700, Richard Henderson wrote:
> On Wed, Oct 12, 2005 at 10:49:44AM -0700, Steve Kargl wrote:
> > How does one set z = 0 - I 0 in a portable manner with gcc?
>
> z = conj(0);
>
I came to your solution after posting my question.
Unfortunately, the point of my original question
was missed. gcc is not following Annex G in n1124.pdf.
In particular, see G.5.1 Multiplicative operators.
y = copysign(0, -1);
z = I * y; /* This should be computed as (i1)*(-0) = -i0 */
/* Upon assignment to z, we have z = 0 - i0 */
--
Steve