From: Eric Hodel <drbrain@...7.net>
Date: 2009-07-22T11:07:20+09:00
Subject: Re: Problems with gems and Ruby 1.8.7

On Jul 18, 2009, at 06:57, Henrique Testa wrote:
> Hi all,
>
> I have ruby 1.8.7 (2008-08-11 patchlevel 72) [universal-darwin10.0]
> installed in my Snow Leopard Preview Release. Rails runs OK, but I  
> can't
> install some gems with native extensions. The following error appear:
>
> $ sudo gem install bluecloth
> Password:
> Building native extensions.  This could take a while...
> ERROR:  Error installing bluecloth:
>  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
>
>
> Gem files will remain installed in
> /Library/Ruby/Gems/1.8/gems/bluecloth-2.0.5 for inspection.
> Results logged to
> /Library/Ruby/Gems/1.8/gems/bluecloth-2.0.5/ext/gem_make.out
>
> The same error happens with many gems. I tried already update rubygem
> (the installed version is 1.3.4), but the problem persist. Any ideas?

You also have the dev tools installed?