[Rails] mysql2 bundle 時錯誤
錯誤訊息: Fetching mysql2 0.3.20 Installing mysql2 0.3.20 with native extensions Gem::Ext::BuildError: ERROR: Failed to build gem native extension. /Users/stan/.rvm/rubies/ruby-2.1.2/bin/ruby extconf.rb checking for ruby/thread.h... yes checking for »