Cannot install MacVim 7.4 on OS X Maverick 10.9.4?
I solved this issue thanks to the following tip I found as to how to install Xcode from the MacPorts page.

excerpt


  2.1.1. Install Xcode on OS X 10.9 or later
  
  Download the latest version of Xcode from the Apple developer
  website or get it using the Mac App Store.
       Once you have Xcode installed, open a terminal, run xcode-select --install, and click the Install button to install the required command line developer tools. Don't worry if you see a message telling
  you the software cannot be installed because it is not currently
  available from the Software Update Server. This usually means you
  already have the latest version installed. You can also get the
  command line tools from the Apple developer website.


The key piece of information was to run this command:

$ xcode-select --install


&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

After installing the command line tools you should be able to successfully install macvim using brew.

$ brew install macvim
==&gt; Downloading https://github.com/b4winckler/macvim/archive/snapshot-73.tar.gz
Already downloaded: /Library/Caches/Homebrew/macvim-7.4-73.tar.gz
==&gt; ./configure --with-features=huge --enable-multibyte --with-macarchs=x86_64 -
==&gt; make
==&gt; Caveats
.app bundles were installed.
Run `brew linkapps` to symlink these to /Applications.
==&gt; Summary
  /usr/local/Cellar/macvim/7.4-73: 1810 files, 28M, built in 30 seconds

$ brew linkapps 
Linking /usr/local/Cellar/macvim/7.4-73/MacVim.app
Finished linking. Find the links under /Applications.