Any idea how to fix this?
Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension. /home/durrantm/.rvm/rubies/ruby-1.9.3-p194/bin/ruby
Another option is to switch to using ruby p125, e.g.
p125
rvm install 1.9.3-p125 rvm use 1.9.3-p125 --default
I had ruby 1.9.3-p194 and apparently that doesn't have the debug/linecache I need.