Installing older libv8 on Yosemite

brew update
brew uninstall v8
brew install apple-gcc42

ln -s /usr/local/Cellar/apple-gcc42/4.2.1-5666.3/bin/gcc-4.2 /usr/local/bin/gcc

ln -s /usr/local/Cellar/apple-gcc42/4.2.1-5666.3/bin/g++-4.2 /usr/local/bin/g++

ln -s /usr/local/Cellar/apple-gcc42/4.2.1-5666.3/bin/cpp-4.2 /usr/local/bin/cpp

gem install libv8

gem install therubyracer

brew uninstall apple-gcc42
rm /usr/local/bin/gcc
rm /usr/local/bin/g++
rm /usr/local/bin/cpp