UPDATE: Use Ruby 2.1.2, it fixes this issue.
14.04 is probably shipping with readline 6.3, which uses rl_hook_func_t
instead of Function
.
This bug has already been reported and fixed in Ruby (https://bugs.ruby-lang.org/issues/9578), but not released yet.
Until Ruby 2.1.2 comes out (which I assume will contain this fix), you can use a patch to properly support the new rl_hook_func_t
method. Use this to install Ruby 2.1.1:
curl -fsSL https://gist.github.com/mislav/a18b9d7f0dc5b9efc162.txt | rbenv install --patch 2.1.1
(Source: http://gorails.com/setup/ubuntu/14.04)