Failed to build gem native extension ( em-irc )

Question

Trying to install em-irc, got that:

/usr/bin/ruby1.9.1 extconf.rb
/usr/local/lib/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require': cannot load such file -- mkmf (LoadError)
from /usr/local/lib/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
from extconf.rb:2:in `<main>'

Answer 1

Try running as root: sudo gem install em-irc