在Ubuntu 15上安装Nokogiri时出错

Question

运行bundle install错误时，Nokigiri安装失败：

Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

/usr/bin/ruby2.1 extconf.rb --use-system-libraries
checking if the C compiler accepts ... yes
Building nokogiri using system libraries.
libxml2 version 2.6.21 or later is required!

我安装了libxml2，仍然在抛出错误。

我可以使用命令

安装gem

gem install nokogiri -- --use-system-libraries=true --with-xml2-include=/usr/include/libxml2

但是当我运行bundle install时它失败了。