language: ruby
rvm:
  - 2.0.0
  - 2.1
  - 2.2
  - ruby-head
addons:
  apt:
    packages:
      - libgmp-dev

language: ruby
rvm:
  - 2.0.0
  - 2.1
  - 2.2
  - ruby-head
addons:
  apt:
    packages:
      - libgmp-dev
      - build-essential

Add build essential for Travis
Add build essential for Travis
