Phobos unit testing uncovers a CPU bug

[Walter Bright]

Kagamin wrote:
> Don Wrote:
> 
>> The Intel CPU gives the correct answer, but AMD's is wrong. They should 
>> both give the correct result.
> 
> Really? I think, the answer is neither correct nor wrong. It's approximate.

The rules for rounding the mathematical value to the representation are precise, 
and so there is such a thing as the correctly rounded result and the wrong result.

An FPU should strive to always produce the correctly rounded result.