Nokogiri 'Fehler beim Erstellen der nativen Gem-Erweiterung' beim Ausführen der Bundle-Installation

Ich rennebundle install und ich erhalte diesen Fehler:

Building nokogiri using system libraries.

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

    /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/bin/ruby extconf.rb --use-system-libraries
Building nokogiri using system libraries.
libxml2 version 2.6.21 or later is required!
*** 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=/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/bin/ruby
    --help
    --clean
    --use-system-libraries
    --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-xml2-dir
    --without-xml2-dir
    --with-xml2-include
    --without-xml2-include=${xml2-dir}/include
    --with-xml2-lib
    --without-xml2-lib=${xml2-dir}/lib
    --with-libxml-2.0-config
    --without-libxml-2.0-config
    --with-pkg-config
    --without-pkg-config
    --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-exslt-dir
    --without-exslt-dir
    --with-exslt-include
    --without-exslt-include=${exslt-dir}/include
    --with-exslt-lib
    --without-exslt-lib=${exslt-dir}/lib
    --with-libexslt-config
    --without-libexslt-config
    --with-pkg-config
    --without-pkg-config

extconf failed, exit code 1

Gem files will remain installed in /Users/myuser/projectpath/vendor/bundle/ruby/2.0.0/gems/nokogiri-1.6.2.rc2 for inspection.
Results logged to /Users/myuser/projectpath/vendor/bundle/ruby/2.0.0/extensions/universal-darwin-13/2.0.0/nokogiri-1.6.2.rc2/gem_make.out
An error occurred while installing nokogiri (1.6.2.rc2), and Bundler cannot continue.
Make sure that `gem install nokogiri -v '1.6.2.rc2'` succeeds before bundling.

Irgendwelche Ideen, was könnte das sein?

BEARBEITEN:

Ich habe auch nokogiri installiert, das dem folgtAnweisungen im Tutorial, und das Seltsame ist, dass der Edelstein erfolgreich installiert wurde. Wenn ich rennegem list, Ich habenokogiri (1.6.2.1), aber beim rennenbundle install es zeigt den Fehler an.