Command-T for VIM Installation extconf.rb Failed Error

The Command-T plug-in provides an extremely fast, intuitive mechanism for
opening files and buffers with a minimal number of keystrokes. It’s named
“Command-T” because it is inspired by the “Go to File” window bound to
Command-T in TextMate.

I was trying to install Command-T into VIM with the Pathogen plugin. I kept getting

checking for ruby.h... *** extconf.rb failed 
***Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

I realized my rvm environment was choosing the incorrect gcc and developer tools. I used the system ruby and was able to run everything without a hitch.

rvm use system    
cd ruby/command-t
ruby extconf.rb
make
sudo make install