It's a little bit interesting that -2.0, -1.0 and -0.0, when multiplied by zero, are yielding 0 instead of -0.
It looks, at first glance, like a half-arsed stuff up.

But the very act of multiplying the NV's -2.0, -1.0 and -0.0 by any whole number sets the IV flags and places 0 in the IV (int) slot. The signedness of the zero is therefore lost. Signedness of zero, is defined only for floating point (float/double) zeroes - so the 0 in the IV slot will always be unsigned.

The other numbers, being non-integral values, will preserve their NV flags when mutliplied, and the value printed for them will be the value that's stored in the NV (double) slot - thus allowing for the appearance of -0 (when supported by the underlying conditions).

Cheers,
Rob

In reply to Re: Negative zero from a multiplication by a zero? by syphilis
in thread Negative zero from a multiplication by a zero? by Anonymous Monk

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