ERROR: Error installing kingpong-ruby-mcrypt: ERROR: Failed to build gem native extension.

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

    /Users/ahmadhassan/.rvm/rubies/ruby-1.9.3-p194/bin/ruby -r ./siteconf20150107-15315-1f92990.rb extconf.rb 
checking for mcrypt.h... no

########################################################################

Unable to find your mcrypt library.

Make sure you have libmcrypt installed (and libmcrypt-devel if you're
on a Linux distribution that does things that way).

If your libmcrypt is in a nonstandard location and has header files in
PREFIX/include and libraries in PREFIX/lib, try installing the gem like
this (note the extra "--"):

  gem install kingpong-ruby-mcrypt --source=http://gems.github.com \
      -- --with-mcrypt-dir=/path/to/mcrypt/prefix

You can also specify the include and library directories separately:

  gem install kingpong-ruby-mcrypt --source=http://gems.github.com \
      -- --with-mcrypt-include=/path/to/mcrypt/include \
         --with-mcrypt-lib=/path/to/mcrypt/lib

Specifically, if you're using MacPorts, this should work for you:

  sudo port install libmcrypt +universal
  sudo gem install kingpong-ruby-mcrypt --source=http://gems.github.com \
      -- --with-mcrypt-dir=/opt/local

########################################################################

*** 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
        --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/ahmadhassan/.rvm/rubies/ruby-1.9.3-p194/bin/ruby
        --with-mcrypt-dir
        --without-mcrypt-dir
        --with-mcrypt-include
        --without-mcrypt-include=${mcrypt-dir}/include
        --with-mcrypt-lib
        --without-mcrypt-lib=${mcrypt-dir}/lib

extconf failed, exit code 1

Gem files will remain installed in /Users/ahmadhassan/.rvm/gems/ruby-1.9.3-p194@call_center/gems/ruby-mcrypt-0.1.1 for inspection.
Results logged to /Users/ahmadhassan/.rvm/gems/ruby-1.9.3-p194@call_center/extensions/x86_64-darwin-14/1.9.1/ruby-mcrypt-0.1.1/gem_make.out
An error occurred while installing ruby-mcrypt (0.1.1), and Bundler cannot continue.
Make sure that `gem install ruby-mcrypt -v '0.1.1'` succeeds before bundling.





Solution :


brew install libmcrypt