Metasploit - ERROR: cannot discover where libxml2 is located on your system

metasploit-framework [rapid7-master] ->> rvm listrvm rubies=* ruby-2.3.3 [ x86_64 ]# => - current# =* - current && default#  * - default

When ruby is updated from ruby-2.3.1 to ruby-2.3.3. It will make errors as follow.

metasploit-framework [rapid7-master] ->> bundle installFetching gem metadata from https://rubygems.org/...........Fetching version metadata from https://rubygems.org/..Fetching dependency metadata from https://rubygems.org/.Resolving dependencies...Using rake 11.3.0Using i18n 0.7.0Using json 1.8.3Using minitest 5.10.1Using thread_safe 0.3.5Using builder 3.2.2Using erubis 2.7.0Using mini_portile2 2.1.0Using rack 1.6.5Using arel 6.0.3Using public_suffix 2.0.4Using ffi 1.9.14Using contracts 0.14.0Using gherkin 4.0.0Using cucumber-wire 0.0.1Using diff-lcs 1.2.5Using multi_json 1.12.1Using multi_test 0.1.2Using rspec-support 3.5.0Using thor 0.19.4Using bcrypt 3.1.11Using bit-struct 0.15.0Using mime-types-data 3.2016.0521Using coderay 1.1.1Using docile 1.1.5Using multipart-post 2.0.0Using filesize 0.1.1Using fivemat 1.3.2Using rkelly-remix 0.0.6Using metasm 1.0.2Using pg 0.19.0Using pg_array_parser 0.0.9Using rubyntlm 0.6.1Using rubyzip 1.2.0Using metasploit-payloads 1.2.3Using metasploit_payloads-mettle 0.1.3Using msgpack 1.0.2Using nessus_rest 0.1.6Using net-ssh 3.2.0Using network_interface 0.0.1Using openssl-ccm 1.2.1Using openvas-omp 0.0.4Using pcaprub 0.12.4Using patch_finder 1.0.2Using rb-readline-r7 0.5.2.0Using redcarpet 3.3.4Using rex-text 0.2.9Using rex-core 0.1.3Using rex-struct2 0.1.0Using rex-java 0.1.3Using rex-registry 0.1.1Using robots 0.10.1Using sqlite3 1.3.12Using sshkey 1.8.0Using windows_error 0.0.2Using method_source 0.8.2Using slop 3.6.0Using simplecov-html 0.10.0Using timecop 0.8.1Using yard 0.9.5Using bundler 1.13.6Using tzinfo 1.2.2Installing nokogiri 1.6.8.1 with native extensionsUsing rack-test 0.6.3Using addressable 2.5.0Using childprocess 0.5.9Using cucumber-core 1.5.0Using rspec-expectations 3.5.0Using rspec-core 3.5.4Using rspec-mocks 3.5.0Using mime-types 3.1Using faraday 0.10.0Using jsobfu 0.4.1Using packetfu 1.1.11Using rex-arch 0.1.2Using rex-mime 0.1.1Using rex-ole 0.1.3Using rex-random_identifier 0.1.1Using rex-zip 0.1.1Using rex-rop_builder 0.1.1Using rex-socket 0.1.2Using pry 0.10.4Using simplecov 0.12.0Using activesupport 4.2.7.1Using tzinfo-data 1.2016.10Gem::Ext::BuildError: ERROR: Failed to build gem native extension.    current directory: /Users/seclab/.rvm/gems/ruby-2.3.3@metasploit-framework/gems/nokogiri-1.6.8.1/ext/nokogiri/Users/seclab/.rvm/rubies/ruby-2.3.3/bin/ruby -r ./siteconf20161206-46534-atycag.rb extconf.rb --use-system-librarieschecking if the C compiler accepts ... yeschecking if the C compiler accepts -Wno-error=unused-command-line-argument-hard-error-in-future... noBuilding nokogiri using system libraries.ERROR: cannot discover where libxml2 is located on your system. please make sure `pkg-config` is installed.*** extconf.rb failed ***Could not create Makefile due to some reason, probably lack of necessarylibraries and/or headers.  Check the mkmf.log file for more details.  You mayneed 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/seclab/.rvm/rubies/ruby-2.3.3/bin/$(RUBY_BASE_NAME)    --help    --clean    --use-system-libraries    --with-zlib-dir    --without-zlib-dir    --with-zlib-include    --without-zlib-include=${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=${xslt-dir}/lib    --with-libxslt-config    --without-libxslt-config    --with-exslt-dir    --without-exslt-dir    --with-exslt-include    --without-exslt-include=${exslt-dir}/include    --with-exslt-lib    --without-exslt-lib=${exslt-dir}/lib    --with-libexslt-config    --without-libexslt-configTo see why this extension failed to compile, please check the mkmf.log which can be found here:  /Users/seclab/.rvm/gems/ruby-2.3.3@metasploit-framework/extensions/x86_64-darwin-16/2.3.0/nokogiri-1.6.8.1/mkmf.logextconf failed, exit code 1Gem files will remain installed in /Users/seclab/.rvm/gems/ruby-2.3.3@metasploit-framework/gems/nokogiri-1.6.8.1 for inspection.Results logged to /Users/seclab/.rvm/gems/ruby-2.3.3@metasploit-framework/extensions/x86_64-darwin-16/2.3.0/nokogiri-1.6.8.1/gem_make.outAn error occurred while installing nokogiri (1.6.8.1), and Bundler cannot continue.Make sure that `gem install nokogiri -v '1.6.8.1'` succeeds before bundling.

metasploit-framework [rapid7-master] ->> xcode-select --installxcode-select: note: install requested for command line developer toolsmetasploit-framework [rapid7-master] ->> gem install nokogiri -v '1.6.8.1'Building native extensions.  This could take a while...Successfully installed nokogiri-1.6.8.1Parsing documentation for nokogiri-1.6.8.1Installing ri documentation for nokogiri-1.6.8.1Done installing documentation for nokogiri after 2 seconds1 gem installed