我总是无法在OSX 10.8.4的新Air上安装rails，即使我成功安装了XCode的命令行工具ruby2，当我尝试安装rails时，它仍然会提示一些错误。
我从网上找到了很多解决方案，但它们都不适用于我的问题，我完全困惑了，没有任何解决方案能帮助我吗？我真的很感激！！！
localhost:myapp zerocool$ ruby -v
ruby 2.0.0p247 (2013-06-27 revision 41674) [x86_64-darwin12.3.0]
localhost:myapp zerocool$ sudo gem install rails
Password:
Building native extensions. This could take a while...
ERROR: Error installing rails:
ERROR: Failed to build gem native extension.
/Users/zerocool/.rvm/rubies/ruby-2.0.0-p247/bin/ruby extconf.rb
*** 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/zerocool/.rvm/rubies/ruby-2.0.0-p247/bin/ruby
--with-atomic_reference-dir
--without-atomic_reference-dir
--with-atomic_reference-include
--without-atomic_reference-include=${atomic_reference-dir}/include
--with-atomic_reference-lib
--without-atomic_reference-lib=${atomic_reference-dir}/
/Users/zerocool/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/mkmf.rb:434:in `try_do': The compiler failed to generate an executable file. (RuntimeError)
You have to install development tools first.
from /Users/zerocool/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/mkmf.rb:519:in `try_link0'
from /Users/zerocool/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/mkmf.rb:817:in `try_run'
from extconf.rb:24:in `<main>'
Gem files will remain installed in /Users/zerocool/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/gems/2.0.0/gems/atomic-1.1.12 for inspection.
Results logged to /Users/zerocool/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/gems/2.0.0/gems/atomic-1.1.12/ext/gem_make.out
我今天遇到了这个问题，我下载的ruby-2.0.0似乎无法正常工作。我建议先尝试rvm reinstall 2.0.0，然后再尝试gem install rails。
终于找到了解决方案！运行rvm内爆，并使用rm删除/etc/rvmrc和~/.rmvrc，重新启动mac，然后可以使用gem install rails成功安装rails。
首先，我通过自制程序安装了gcc：
使用brew 在mavericks上安装gcc
brew tap homebrew/dupesbrew install apple-gcc42然后我符号链接了新安装的应用程序-gcc42进入我的/usr/bin文件夹
cd /usr/bin
sudo mv gcc gcc_mavs sudo ln -s /usr/local/Cellar/apple-gcc42/4.2.1-5666.3/bin/gcc-4.2 gcc
学分：https://coderwall.com/p/lqpp8w
我在运行ruby 2.0.0-p195时也遇到了同样的错误，但更新到ruby 2.0.0-p247（2.0.0的当前RVM默认值）修复了这个错误。