gem install therubyracer -v 0.11.4 fails on OS X 10.10

Question

Following the steps here "gem install therubyracer -v '0.10.2'" on osx mavericks not installing, I was able to get therubyracer -v 0.10.2 and 0.12.0 to ins

Answer 1

I finally got therubyracer 0.11.4 to install and working using Xcode 6.1.1, 6.2 beta or 6.3 beta (I've tested all 3) and also Xcode 4.6.3 (available at: https://developer.apple.com/downloads/index.action) then running:

# rename your current version of Xcode to make it distinguishable
sudo mv /Applications/Xcode.app /Applications/$(xcodebuild -version | head -1 | sed -e 's/ //').app

# Download and install Xcode 4.6.3 and run:
sudo mv /Applications/Xcode.app /Applications/Xcode4.6.3.app

# Switch to your 4.6.3 version of Xcode
sudo xcode-select --switch /Applications/Xcode4.6.3.app

# Install the version of libv8 that's tied to your version of TRR:
gem install libv8 -v '3.11.8.17'

# Switch back to you original version of Xcode
sudo xcode-select --switch /Applications/Xcode6.x.app

# Install TRR
gem install therubyracer -v '0.11.4'