[PATCH 1/3] msvcrt: Don't set errno when calling trigonometric functions with NAN.

[Piotr Caban]

Hi,

I've done some more reading about it and it looks like our 
implementation is not behaving in similar way as native does. The error 
handling should call _matherr function (see also __setusermatherr).

Thanks to implementing it that way we easily write code that is 
compatible with older versions of C-runtime (by providing different 
default implementation of matherr function that prevents setting errno). 
I think it's best to implement it that way to avoid potential regressions.

Thanks,
Piotr