Install therubyracer gem on OSX 10.11 El Capitan

I still had issues with @xxjjnn's answer. The following answer from github resolved it. My current setup: El Capitan 10.11.4 and Xcode 7.3.

brew tap homebrew/versions
brew install v8-315

gem install libv8 -v '3.16.14.13' -- --with-system-v8
gem install therubyracer -- --with-v8-dir=/usr/local/opt/v8-315

bundle install

The answer provided on therubyracer Github page worked for me:

brew tap homebrew/versions
brew install v8-315
brew link --force v8-315
gem install libv8 -- --with-system-v8
gem install therubyracer

1. Install xcode through app store
2. Install 'command line tools' for xcode (xcode-select --install)
3. If using rbenv, after installing ruby you needed rbenv rehash

4. Assuming you have run gem install bundler and got errors, remove your mess:

   gem uninstall libv8
   gem uninstall therubyracer
   brew rm v8
   

5. Install gcc4.2

   brew tap homebrew/dupes
   brew install apple-gcc42
   

6. Install v8

   brew tap homebrew/versions
   brew install v8-315
   brew link --force v8-315
   

7. Install gems

   gem install libv8 -- --with-system-v8
   gem install therubyracer
   

   if you get dyld: lazy symbol binding failed: Symbol not found, @rpbaltazar suggests an alternative:

   bundle config --local build.libv8 --with-cxx=/usr/local/bin/g++-4.2
   bundle install