On Mon, 15 Jun 2015, Maciej W. Rozycki wrote: > > It is only required (well, recommended) to pass the *payload*. The sign > > bit is not part of the payload. "For all other operations, this standard > > does not specify the sign bit of a NaN result, even when there is only one > > input NaN, or when the NaN is produced from an invalid operation.". > > However elsewhere: "For an operation with quiet NaN inputs, other than > maximum and minimum operations, if a floating-point result is to be > delivered the result shall be a quiet NaN which should be one of the input > NaNs.".
See <http://grouper.ieee.org/groups/754/email/msg03893.html>: "The intent is that NaNs which differ only in the sign bit are considered equivalent for the purposes of 6.2.". -- Joseph S. Myers jos...@codesourcery.com
