title: Installing mysql2 gem on Mac os x Lion
body: <p>The other day I updated to Mac OSX Lion. It broke my rails install as I had to re complie mysql. While I have got that working reinstalling the mysql2 gem has become problematic. I was perviously running leopard so I am going from 32 to 64 bit.</p>
  
  <pre><code>  ~/code/rails/london (master)$ gem install mysql2 -- --with-mysql-dir=/usr/local/mysql
    Building native extensions.  This could take a while...
    ERROR:  Error installing mysql2:
      ERROR: Failed to build gem native extension.
  
            /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/bin/ruby extconf.rb --with-mysql-dir=/usr/local/mysql
    checking for rb_thread_blocking_region()... *** 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/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/bin/ruby
    /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/mkmf.rb:368:in `try_do': The complier failed to generate an executable file. (RuntimeError)
    You have to install development tools first.
      from /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/mkmf.rb:435:in `try_link0'
      from /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/mkmf.rb:440:in `try_link'
      from /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/mkmf.rb:552:in `try_func'
      from /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/mkmf.rb:797:in `block in have_func'
      from /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/mkmf.rb:693:in `block in checking_for'
      from /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/mkmf.rb:280:in `block (2 levels) in postpone'
      from /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/mkmf.rb:254:in `open'
      from /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/mkmf.rb:280:in `block in postpone'
      from /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/mkmf.rb:254:in `open'
      from /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/mkmf.rb:276:in `postpone'
      from /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/mkmf.rb:692:in `checking_for'
      from /Users/stewartmatheson/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/mkmf.rb:796:in `have_func'
      from extconf.rb:9:in `&lt;main&gt;'
  
  
    Gem files will remain installed in /Users/stewartmatheson/.rvm/gems/ruby-1.9.2-p0@london/gems/mysql2-0.3.7 for inspection.
    Results logged to /Users/stewartmatheson/.rvm/gems/ruby-1.9.2-p0@london/gems/mysql2-0.3.7/ext/mysql2/gem_make.out
  </code></pre>
  
  <p>So far I have recompiled and installed MySQL and updated RVM to head. I have also installed Xcode however I have had no luck.</p>
  
  <p>Suggestions?</p>