While bundle install the error: Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension. /home/launchpad/.rbenv/versions/1.9.3-p448/bin/ruby extconf.rb Can't handle 1.9.x yet * 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. Provided configuration options: --with-opt-dir --without-opt-dir --with-opt-include --without-opt-include=${opt-dir}/include --with-opt-lib --without-opt-lib=${opt-dir}/lib --with-make-prog --without-make-prog --srcdir=. --curdir --ruby=/home/launchpad/.rbenv/versions/1.9.3-p448/bin/ruby Gem files will remain installed in /home/launchpad/.rbenv/versions/1.9.3-p448/lib/ruby/gems/1.9.1/gems/linecache-0.46 for inspection. Results logged to /home/launchpad/.rbenv/versions/1.9.3-p448/lib/ruby/gems/1.9.1/gems/linecache-0.46/ext/gem_make.out An error occurred while installing linecache (0.46), and Bundler cannot continue. Make sure that gem install linecache -v '0.46' succeeds before bundling.