问在OSX 10.9 Maverick上安装Nokogiri时出错？

EN

Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.

/Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/bin/ruby extconf.rb
checking for libxml/parser.h... *** 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
    --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=/Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/bin/ruby
    --with-zlib-dir
    --without-zlib-dir
    --with-zlib-include
    --without-zlib-include=${zlib-dir}/include
    --with-zlib-lib
    --without-zlib-lib=${zlib-dir}/lib
    --with-iconv-dir
    --without-iconv-dir
    --with-iconv-include
    --without-iconv-include=${iconv-dir}/include
    --with-iconv-lib
    --without-iconv-lib=${iconv-dir}/lib
    --with-xml2-dir
    --without-xml2-dir
    --with-xml2-include
    --without-xml2-include=${xml2-dir}/include
    --with-xml2-lib
    --without-xml2-lib=${xml2-dir}/lib
    --with-xslt-dir
    --without-xslt-dir
    --with-xslt-include
    --without-xslt-include=${xslt-dir}/include
    --with-xslt-lib
    --without-xslt-lib=${xslt-dir}/lib
    --with-libxslt-config
    --without-libxslt-config
    --with-pkg-config
    --without-pkg-config
    --with-libxml-2.0-config
    --without-libxml-2.0-config
    --with-libiconv-config
    --without-libiconv-config
/Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:368:in `try_do': The complier failed to generate an executable file. (RuntimeError)
You have to install development tools first.
    from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:452:in `try_cpp'
    from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:853:in `block in find_header'
    from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:693:in `block in checking_for'
    from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:280:in `block (2 levels) in postpone'
    from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:254:in `open'
    from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:280:in `block in postpone'
    from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:254:in `open'
    from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:276:in `postpone'
    from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:692:in `checking_for'
    from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:852:in `find_header'
    from extconf.rb:116:in `<main>'


Gem files will remain installed in /Users/ericcamalionte/Locaweb/code/dns-panel/vendor/bundle/ruby/1.9.1/gems/nokogiri-1.5.9 for inspection.
Results logged to /Users/ericcamalionte/Locaweb/code/dns-panel/vendor/bundle/ruby/1.9.1/gems/nokogiri-1.5.9/ext/nokogiri/gem_make.out
An error occured while installing nokogiri (1.5.9), and Bundler cannot continue.
Make sure that `gem install nokogiri -v '1.5.9'` succeeds before bundling.