1. brew install vim cmake
2. git clone https://github.com/Valloric/YouCompleteMe.git ~/.vim/bundle/YouCompleteMe
3. cd ~/.vim/bundle/YouCompleteMe
4. ./install.sh --clang-completer
2. git clone https://github.com/Valloric/YouCompleteMe.git ~/.vim/bundle/YouCompleteMe
3. cd ~/.vim/bundle/YouCompleteMe
4. ./install.sh --clang-completer
The problem appeared to be that YCM's install.sh script goes out of its way to determine the active version of python and link against its libraries[1].
For anyone with python installed via homebrew, that means it links to 2.7.3. Unfortunately, both MacVim and the homebrew version of vim link against the system python (2.7.2). As a result, loading YCM triggers an error resolving urandom and crashes vim.
[1] https://github.com/Valloric/YouCompleteMe/blob/master/instal...