Warning: "/usr/include/ncursesw" is unsafe for cross-compilation

[Joakim Tjernlund]

In Gentoo[1] one can see this warning when cross building ncurses with 
unicode support:
  cc1: warning: include location "/usr/include/ncursesw" is unsafe for 
cross-compilation [-Wpoison-system-directories]
This is because ncurses adds -I\${includedir} to CPPFLAGS, simply removing 
this makes it build
without this warning.

[1] https://bugs.gentoo.org/show_bug.cgi?id=522586

   Jocke

PS.
    Why are there no proper releases of ncurses? I can just find a lot of 
patches
    Is the a public repo somewhere?