4.1.0 configure problem re kind 10 for cygwin

[FX Coudert]

 > Then, libgfortran attempts to build the
> selected_real_kinds.f90 with kind 10 included, but fails.

We'd need the exact error message for that. As well as the kinds.h file.

> but there is no C 
> library support for it in Cygwin, and both the libstdc++ and libgfortran 
> configure scripts appear to figure that out OK.

You mean all the long double math functions are not available?

FX