Why does installing Nokogiri on Mac OS fail with libiconv is missing?

Question

I've been trying to install Nokogiri on Mac OS 10.9.3 and whatever I try, the install fails in the end with the following error message:

$ sudo gem install nokogiri -- --with-xml2-include=/usr/local/Cellar/libxml2/2.9.1/include/libxml2 --with-xml2-lib=/usr/local/Cellar/libxml2/2.9.1/lib --with-xslt-dir=/usr/local/Cellar/libxslt/1.1.28 --with-iconv-include=/usr/local/Cellar/libiconv/1.14/include --with-iconv-lib=/usr/local/Cellar/libiconv/1.14/lib
Building native extensions with: '--with-xml2-include=/usr/local/Cellar/libxml2/2.9.1/include/libxml2 --with-xml2-lib=/usr/local/Cellar/libxml2/2.9.1/lib --with-xslt-dir=/usr/local/Cellar/libxslt/1.1.28 --with-iconv-include=/usr/local/Cellar/libiconv/1.14/include --with-iconv-lib=/usr/local/Cellar/libiconv/1.14/lib'
This could take a while...
Building nokogiri using packaged libraries.
ERROR:  Error installing nokogiri:
    ERROR: Failed to build gem native extension.

    /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/bin/ruby extconf.rb --with-xml2-include=/usr/local/Cellar/libxml2/2.9.1/include/libxml2 --with-xml2-lib=/usr/local/Cellar/libxml2/2.9.1/lib --with-xslt-dir=/usr/local/Cellar/libxslt/1.1.28 --with-iconv-include=/usr/local/Cellar/libiconv/1.14/include --with-iconv-lib=/usr/local/Cellar/libiconv/1.14/lib
Building nokogiri using packaged libraries.
checking for iconv.h... yes
checking for iconv_open() in iconv.h... no
checking for iconv_open() in -liconv... no
checking for libiconv_open() in iconv.h... no
checking for libiconv_open() in -liconv... no
-----
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=/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/bin/ruby
    --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


Gem files will remain installed in /Library/Ruby/Gems/2.0.0/gems/nokogiri-1.6.2.1 for inspection.
Results logged to /Library/Ruby/Gems/2.0.0/gems/nokogiri-1.6.2.1/ext/nokogiri/gem_make.out

After following a lot of help found around the web including building and installing libxml2 and libxslt using brew and building libiconv from the sources (as described in "Installing Nokogiri"), the error remains the same.

When trying to run the installation for Nokogiri, libxml2 and libxslt seem to be found fine, but not libiconv.

Anyone with a better knowledge of these things know how to get Nokogiri installed?

Answer 1

I had the same issue. Unfortunately the "Installing Nokogiri" doesn't cover Iconv issues. Here's how I resolved the issue.

First install homebrew, it'll make your life easier. If you already have it installed, be sure to grab the latest formulae by updating like so:

brew update

Note: In OSX 10.9+ you may need to install xCode command tools to allow you to install libiconv.

xcode-select --install

then install a newer version of libiconv

brew install libiconv

then install your gem

gem install nokogiri -- --with-iconv-dir=/usr/local/Cellar/libiconv/1.14