Somehow rails stopped working so I was trying to reinstall it, but I got this error:
ERROR: The provided CC(/usr/bin/gcc) is LLVM based, it is not yet fully supported by ruby and gems, please read rvm requirements.
Found this post: http://stackoverflow.com/questions/8000145/ruby-rvm-llvm-and-mysql
Did
rvm get head
rvm install
That fixed my problem