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incomplete specification of the copysign function



Draft 1.4.0 says:

  sourceFormat copySign(source, source)
    copySign(x, y) copies a floating-point operand x to a destination
    in the same format as x, but with the sign of y.

but doesn't say what happens when y is 0 or is a NaN. I assume that
it should say:

  sourceFormat copySign(source, source)
    copySign(x, y) copies a floating-point operand x to a destination
    in the same format as x, but with the sign *bit* of y.

the sign bit being defined in Section 7.3 (though NaN will not always
be propagated). Is it what the IEEE 754-1985 standard implied?

-- 
Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.org/>
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Work: CR INRIA - computer arithmetic / Arenaire project (LIP, ENS-Lyon)

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