Error installing nokogiri: Failed to build gem native extension & libiconv is missing (OSX)

Question

I try to clone this repo and run bundle install. The bundle process failed and throw this error:

    ...
    Installing nokogiri 1.6.2.1 with native extensions
    Building nokogiri using packaged libraries.

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

        /Users/zulhilmizainudin/.rvm/rubies/ruby-2.2.0/bin/ruby -r ./siteconf20151130-43880-pntnc6.rb extconf.rb
    Building nokogiri using packaged libraries.
    -----
    libiconv is missing.  please visit http://nokogiri.org/tutorials/installing_nokogiri.html for help with installing dependencies.
    -----
    *** 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=/Users/zulhilmizainudin/.rvm/rubies/ruby-2.2.0/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}/lib
        --enable-cross-build
        --disable-cross-build

    extconf failed, exit code 1

    Gem files will remain installed in /Users/zulhilmizainudin/.rvm/gems/ruby-2.2.0/gems/nokogiri-1.6.2.1 for inspection.
    Results logged to /Users/zulhilmizainudin/.rvm/gems/ruby-2.2.0/extensions/x86_64-darwin-14/2.2.0-static/nokogiri-1.6.2.1/gem_make.out
    An error occurred while installing nokogiri (1.6.2.1), and Bundler cannot continue.
    Make sure that `gem install nokogiri -v '1.6.2.1'` succeeds before bundling.

Then I try to run this:

gem install nokogiri -v '1.6.2.1'

And now I get this error:

Building native extensions.  This could take a while...
Building nokogiri using packaged libraries.
ERROR:  Error installing nokogiri:
    ERROR: Failed to build gem native extension.

    /Users/zulhilmizainudin/.rvm/rubies/ruby-2.2.0/bin/ruby -r ./siteconf20151130-43942-1axq4sj.rb extconf.rb
Building nokogiri using packaged libraries.
-----
libiconv is missing.  please visit http://nokogiri.org/tutorials/installing_nokogiri.html for help with installing dependencies.
-----
*** 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=/Users/zulhilmizainudin/.rvm/rubies/ruby-2.2.0/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}/lib
    --enable-cross-build
    --disable-cross-build

extconf failed, exit code 1

Gem files will remain installed in /Users/zulhilmizainudin/.rvm/gems/ruby-2.2.0/gems/nokogiri-1.6.2.1 for inspection.
Results logged to /Users/zulhilmizainudin/.rvm/gems/ruby-2.2.0/extensions/x86_64-darwin-14/2.2.0-static/nokogiri-1.6.2.1/gem_make.out

I tried to follow this answer but I still get the same error above.

I also try to uninstall and install my brew again (based on this answer) and it's still same.

Also, I try this solution but still get the error.

What should I do now to make sure this nokogiri gem installed successfully?

Note: I'm using OSX 10.11.1 El Capitan.

Answer 1

Run these commands:

gem uninstall nokogiri
xcode-select --install
gem install nokogiri

source: http://www.nokogiri.org/tutorials/installing_nokogiri.html#mac_os_x

sometimes mac updates can break xcode CLI so reinstalling can fix the issue: https://github.com/sparklemotion/nokogiri/issues/1445