[PATCH] include: Add some math function declarations.

[Daniel Lehman]

> On 02/07/18 08:10, Daniel Lehman wrote:
> > +int __cdecl _isnan(double);
> _isnan is defined in float.h. Is it really redefined in math.h file?
ah, right.  only isnan is math.h.  I'll send a new one

thanks
daniel