title: sqlite3 gem fails to install
body: <p>I'm trying to install the "sqlite3-ruby" gem (or the "sqlite3" gem) on OS X 10.6. I'm using ruby-1.9.2 and I currently get the following:</p>
  
  <pre><code> $ sqlite3 --version
  3.7.4
   $ sudo gem install sqlite3
  Building native extensions.  This could take a while...
  ERROR:  Error installing sqlite3-ruby:
      ERROR: Failed to build gem native extension.
  
  /Users/folken/.rvm/rubies/ruby-1.9.2-head/bin/ruby extconf.rb
  checking for sqlite3.h... *** 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/folken/.rvm/rubies/ruby-1.9.2-head/bin/ruby
      --with-sqlite3-dir
      --without-sqlite3-dir
      --with-sqlite3-include
      --without-sqlite3-include=${sqlite3-dir}/include
      --with-sqlite3-lib
      --without-sqlite3-lib=${sqlite3-dir}/lib
  /Users/folken/.rvm/rubies/ruby-1.9.2-head/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/folken/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/mkmf.rb:452:in `try_cpp'
      from /Users/folken/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/mkmf.rb:853:in `block in find_header'
      from /Users/folken/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/mkmf.rb:693:in `block in checking_for'
      from /Users/folken/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/mkmf.rb:280:in `block (2 levels) in postpone'
      from /Users/folken/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/mkmf.rb:254:in `open'
      from /Users/folken/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/mkmf.rb:280:in `block in postpone'
      from /Users/folken/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/mkmf.rb:254:in `open'
      from /Users/folken/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/mkmf.rb:276:in `postpone'
      from /Users/folken/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/mkmf.rb:692:in `checking_for'
      from /Users/folken/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/mkmf.rb:852:in `find_header'
      from extconf.rb:28:in `&lt;main&gt;'
  
  
  Gem files will remain installed in /Users/folken/.rvm/gems/ruby-1.9.2-head/gems/sqlite3-1.3.3 for inspection.
  </code></pre>
  
  <p>The following is the results of which &amp; whereis, and the sqlite3.h is located in /opt/local/include:</p>
  
  <pre><code> $ which sqlite3
  /opt/local/bin/sqlite3
   $ whereis sqlite3
  /usr/bin/sqlite3
  </code></pre>
  
  <p>I've tried passing in the following as well:</p>
  
  <pre><code>sudo gem install sqlite3 -- --with-sqlite3-include /opt/local/include --with-sqlite3-lib /opt/local/lib
  sudo gem install sqlite3 -- --with-sqlite3-dir /opt/local/bin
  </code></pre>
  
  <p>which results in the following:</p>
  
  <pre><code>ERROR:  Error installing sqlite3-ruby:
      ERROR: Failed to build gem native extension.
  
  /Users/folken/.rvm/rubies/ruby-1.9.2-head/bin/ruby extconf.rb --with-sqlite3-dir /usr/bin/sqlite3
  *** 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/folken/.rvm/rubies/ruby-1.9.2-head/bin/ruby
      --with-sqlite3-dir
  /Users/folken/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/mkmf.rb:1336:in `dir_config': undefined method `split' for true:TrueClass (NoMethodError)
      from extconf.rb:9:in `&lt;main&gt;'
  </code></pre>
  
  <p>Also under /Users/folken/.rvm/gems/ruby-1.9.2-head/gems:
      sqlite-ruby-2.2.3
      sqlite3-1.3.3</p>
  
  <p>Under RVM I have ruby-1.8.7 and the sqlite3 gem loads fine on that, but after much googling I have not found a solution that works for me. Any help is greatly appreciated (even if it involves manual installation / hackery to get working).</p>