I\'ve been working through the Rails install instructions (http://railsapps.github.io/installrubyonrails-mac.html) and everything was okay up until I got to gem instal
gem instal
I had the same problem when I try:
gem install libxml-ruby -v '3.0.0
Run the following solved the issue on Mac for me:
gem update --system xcode-select --install gem install nokogiri
See installing nokogiri for more details