How to test if float is NaN?

[Walter Bright]

Jarrett Billingsley wrote:
> "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.

I suspect it's the other way around. VC dropped 80 bit support long 
before those instructions were added.

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

'real's are supposed to be the longest floating point type available on 
the hardware, so they'd be reals.