Vagrant cannot install nokogiri-dependent plugins

Question

I\'m trying to install the rackspace plugin for vagrant (1.5.1):

vagrant plugin install vagrant-rackspace

But it complains

Answer 1

This worked for me on Mavericks and Vagrant 1.6.1:

CC=/usr/bin/gcc vagrant plugin install vagrant-rackspace

I tried NOKOGIRI_USE_SYSTEM_LIBRARIES=1 but got an error saying that system libxml2 is too old.