If you're on OSX and want a good Emacs, go to https://github.com/railwaycat/emacs-mac-port and read the installation instructions under the Homebrew section. It follows the official Emacs repo pretty closely, but has useful OSX additions (smooth scrolling, gesture support [font size e.g] and more).

That git repo claims to be retired.

I get my emacs from here http://emacsformacosx.com

The repo you're referring to is Railwaycat's mirror of Yamamoto Mitsuharu's codebase. (which previously was only available via ftp and tarballs.)

Yamamoto has recently migrated to git and hosts a repo at Chiba U, the address is: http://www.math.s.chiba-u.ac.jp/~mituharu/emacs-mac.git

HOWEVER. Railwaycat does still maintain the Homebrew tap and formula for installing Emacs Mac Port

Here: https://github.com/railwaycat/homebrew-emacsmacport

A simple install via:

   brew tap railwaycat/emacsmacport
   brew update
   brew install emacs-mac

Once built, you can (without any problems) move the Emacs.app into your /Applications/ folder.

Don't do yourself a disservice, install Emacs Mac Port now.