While trying to set up a VPS running Ubuntu 14.04 I was unable to compile Ruby 2.1.1 (which was the current version). I kept running into errors such as:
The cause is that Ubuntu 14.04 ships with Readline version 6.3 which apparently breaks builds of Ruby and Python. This issue has been solved for Ruby but will likely be available for Ruby until 2.1.2 . In the interim here is the process for compiling ruby 2.1.1 on Ubuntu 14.04.
Get the tar of the current version and untar it:
Change directories into Ruby source
Download this patch from Mislav Marohnić, a contributor to Ruby Build and github staff member:
Apply the patch:
Make and Install as usual:
Ruby should now be installed for the system.