How to test if float is NaN?

[Jarrett Billingsley]

"Walter Bright" <newshound at digitalmars.com> wrote in message 
news:e53c1b$11rl$1 at digitaldaemon.com...

> VC dropping support for 80 bit long doubles is not an encouraging sign.

Well, correct me of I'm wrong, but aren't 80-bit floats being sort of 
"phased out" along with the x87 FP stack in favor of the new SSE2/3 
instruction sets and 128-bit floats?  That might explain their decision.

For that matter, what's the plan for D when it comes to 128-bit floats?  A 
new type?  "quad"?