brew install autoconf automake curl https://raw.github.com/gist/4136373/falcon-gc.diff > $rvm_path/patches/ruby/1.9.3/p327/falcon.patch rvm install 1.9.3-p327 -n fast --patch falcon
Ref: https://gist.github.com/1688857#comment-610401
brew install autoconf automake
OR https://gist.github.com/1868805 if the above fails
The following is optional, if you attempted to do this previously
rvm remove 1.9.3-perf rm -R ~/.rvm/src/ruby-1.9.3-p125-perf
Install the falcon patched ruby
rvm get head rvm install 1.9.3-perf --patch falcon,debug
Ref: https://gist.github.com/4136373 thanks @databyte