mac os gem安装json出现error failed的解决办法

升级到最新的mac os Mavericks。装json出现错误: 代码如下: gem install json -v ‘1.8.1’ Building native extensions. This could take a while... ERROR: Error installing json: ERROR: Failed to build gem native extension. /usr/local/var/rbenv/versions/2.0.0-p247/bin/ruby extconf.rb creating Makefile make “DESTDIR=”