title: Failing to install gem Nokogiri-1.6.6.2
body: <p>I am installing Nokogiri gem with <code>bundle install</code>, but its failing with below error in CentOS 6.6. I installed libxml2, libxslt also.</p>
  
  <pre><code>Building native extensions.  This could take a while...
  ERROR:  Error installing nokogiri-1.6.6.2.gem:
  ERROR: Failed to build gem native extension.
  
  /usr/bin/ruby -r ./siteconf20160301-19713-3tkoho.rb extconf.rb
  checking if the C compiler accepts ... yes
  Building nokogiri using packaged libraries.
  checking for gzdopen() in -lz... yes
  checking for iconv... yes
  ************************************************************************
  IMPORTANT NOTICE:
  
  Building Nokogiri with a packaged version of libxml2-2.9.2
  with the following patches applied:
          - 0001-Revert-Missing-initialization-for-the-catalog-module.patch
          - 0002-Fix-missing-entities-after-CVE-2014-3660-fix.patch
  
  Team Nokogiri will keep on doing their best to provide security
  updates in a timely manner, but if this is a concern for you and want
  to use the system library instead; abort this installation process and
  reinstall nokogiri as follows:
  
      gem install nokogiri -- --use-system-libraries
          [--with-xml2-config=/path/to/xml2-config]
          [--with-xslt-config=/path/to/xslt-config]
  
  If you are using Bundler, tell it to use the option:
  
      bundle config build.nokogiri --use-system-libraries
      bundle install
  
  Note, however, that nokogiri is not fully compatible with arbitrary
  versions of libxml2 provided by OS/package vendors.
  ************************************************************************
  
  Extracting libxml2-2.9.2.tar.gz into tmp/x86_64-redhat-linux-gnu/ports/libxml2/2.9.2... OK
  Running patch with /usr/lib64/ruby/gems/2.2.0/gems/nokogiri-1.6.6.2/ports/patches/libxml2/0001-Revert-Missing-initialization-for-the-catalog-module.patch...
  Running 'patch' for libxml2 2.9.2... ERROR, review '/usr/lib64/ruby/gems/2.2.0/gems/nokogiri-1.6.6.2/ext/nokogiri/tmp/x86_64-redhat-linux-gnu/ports/libxml2/2.9.2/patch.log' to see what happened.
  *** 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}/lib64
          --with-make-prog
          --without-make-prog
          --srcdir=.
          --curdir
          --ruby=/usr/bin/$(RUBY_BASE_NAME)
          --help
          --clean
          --use-system-libraries
          --enable-static
          --disable-static
          --with-zlib-dir
          --without-zlib-dir
          --with-zlib-include
          --without-zlib-include=${zlib-dir}/include
          --with-zlib-lib
          --without-zlib-lib=${zlib-dir}/lib64
          --enable-cross-build
          --disable-cross-build
  /usr/lib64/ruby/gems/2.2.0/gems/mini_portile-0.6.2/lib/mini_portile.rb:279:in `block in execute': Failed to complete patch task (RuntimeError)
          from /usr/lib64/ruby/gems/2.2.0/gems/mini_portile-0.6.2/lib/mini_portile.rb:271:in `chdir'
          from /usr/lib64/ruby/gems/2.2.0/gems/mini_portile-0.6.2/lib/mini_portile.rb:271:in `execute'
          from extconf.rb:311:in `block in patch'
          from extconf.rb:308:in `each'
          from extconf.rb:308:in `patch'
          from /usr/lib64/ruby/gems/2.2.0/gems/mini_portile-0.6.2/lib/mini_portile.rb:108:in `cook'
          from extconf.rb:278:in `block in process_recipe'
          from extconf.rb:177:in `tap'
          from extconf.rb:177:in `process_recipe'
          from extconf.rb:475:in `&lt;main&gt;'
  
  extconf failed, exit code 1
  
  Gem files will remain installed in /usr/lib64/ruby/gems/2.2.0/gems/nokogiri-1.6.6.2 for inspection.
  Results logged to /usr/lib64/ruby/gems/2.2.0/extensions/x86_64-linux/2.2.0/nokogiri-1.6.6.2/gem_make.out
  [root@hh-rcs-push1 gemfiles]#
  </code></pre>