sudo [apt | dnf | port] install gcc

brew tap homebrew/versions
brew install gcc49
ruby-install ruby 2.4.0 -- CC=gcc-4.9

ruby-install ruby 2.2.0 -- --with-openssl-dir=/path/to/where/openssl-1.0.x/is/installed
~/.rubies/ruby-2.2.0/bin/gem install bundler -v '~>1'

brew tap rbenv/tap
brew install rbenv/tap/openssl@1.0
ruby-install ruby 2.2.0 -- --with-openssl-dir=$(brew --prefix openssl@1.0)
~/.rubies/ruby-2.2.0/bin/gem install bundler -v '~>1'