(This is a legacy post from the old website.)
Running afoul of the following error when trying to install rubies with RVM despite having installed Xcode?
Can not find compiler and ‘make’ tool – make sure Xcode and/or Command Line Tools are installed.
With newer versions of Xcode the command line tools RVM expects are not automatically installed alongside Xcode.
Open Xcode and navigate to: Xcode > Preferences > Downloads and click Install for Command Line Tools.