Overtherailing.

Fixing gem installation after Snow Leopard upgrade

If you’re trying to install Ruby gems after upgrading to MacOSX 10.6 and receive the following error:

computron:~ root# gem install json
Building native extensions.  This could take a while...
ERROR:  Error installing json:
	ERROR: Failed to build gem native extension.

/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby extconf.rb
mkmf.rb can't find header files for ruby at /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/ruby.h

…just reinstall XCode off the 10.6 DVD (it’s under Optional Installs). Things should function fine afterwards.