Installing Scipy from MacPorts on Mountain Lion

After doing a fresh install of Mountain Lion I proceeded with my age old tradition of reinstalling all of my favorite libraries from MacPorts. Everything installed wonderfully except for PyObjC, Scipy, and a few of their dependencies like gcc45 and libunwind-headers. With an hour of trial and error that included playing with the pip installer and fighting the temptation to switch to Homebrew, I found an easy and quick fix for MacPorts.

If you have already attempted to install any of those ports I have listed, please clean those ports that have failed to install. For example, my installation of the py27-scipy port failed so I must use the following command to clean it:

sudo port clean --all py27-scipy

The quick fix to allow MacPorts to install these wonderful ports properly is done by reconfirming the Xcode license agreement with the following command:

sudo xcodebuild -license

Continuing from my example, sudo port install py27-scipy should now execute and install without a hitch. The same goes for the other ports I listed earlier.