I'm seeing the same, on both osx and linux.
It seems to be caused by a build script change in commit
5472169814c4a823a6f79a14b3a0ec227ab3cd64.
If you restore the previous lines the addons build again. See e.g.
http://github.com/makuk66/io/commit/0faf1794e3ebd247c26838868cb4aca85c96fd42
Steve, what was this change intended to achieve?
-- Martijn