I setup Eclipse on Window 7 and used Windows toolchain (raspberry-gcc6.3.0.exe from http://gnutoolchains.com/raspberry) to cross compile it. It failed during make. The error is:
....cstdlib:75:25: fatal error: stdlib.h: No such file or directory
#include_next <stdlib.h>.
After goggling for quite a while. I eventually compiled wt4.0.3 successfully with the following options set for cmake;
CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES = true
CMAKE_C_IMPLICIT_INCLUDE_DIRECTORIES = true. So considering the problem solved.
Yeah, looks like that's an issue with your cross compilation toolchain.