[Cfp-interest 1862] copysign(x,-NAN)

[Fred J. Tydeman]

In looking more at IEEE-754-2019, I see that there are two definitions
of copysign() and that I was looking at the wrong one during our teleconference.

For arithmetic interchange formats, NaNs have a sign bit and it is set or copied
by copysign.  I missed this one on my quick read.

For non-interchange formats, NaN has an unspecified sign.  This is what I was
looking at during the call.


---
Fred J. Tydeman        Tydeman Consulting
tydeman at tybor.com      Testing, numerics, programming
+1 (702) 608-6093      Vice-chair of PL22.11 (ANSI "C")
Sample C99+FPCE tests: http://www.tybor.com
Savers sleep well, investors eat well, spenders work forever.