Hello. I've run into this problem too. The solution (well, it's my solution, I don't know if it's the right way to do it) is to comment that lines.
/* XXX This is from Win32's <ctype.h> */
/*
# ifndef _WCHAR_T_DEFINED
typedef unsigned short wchar_t;
# define _WCHAR_T_DEFINED
# endif*/
This way the app gets compiled and runs. :D
I found that in the past (Feb 2004) there has been a discussion to add that lines to make GLUT compile in windows-cygwin.
See here:
http://www.cygwin.com/ml/cygwin/2004-02/msg00993.html
Another way to solve the bug (without modifying external files) may be to add a define:
#define _WCHAR_T_DEFINED 1
It would be nice to understand the source of this bug and notify it to the developers.