Not sure what happened but when I upgraded to Mavericks it says that Rails it not install. I executed the following command:
rails --version
And it said "Rails is not currently installed and run sudo gem install rails".
I run sudo gem install rails and get the following:
ERROR: Error installing rails:
ERROR: Failed to build gem native extension.
/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/bin/ruby extconf.rb
mkmf.rb can't find header files for ruby at /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/include/ruby.h
Gem files will remain installed in /Library/Ruby/Gems/2.0.0/gems/json-1.8.1 for inspection.
UPDATE:
I ran the command gcc --version and got the following:
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.8.sdk/usr/include/c++/4.2.1
Apple LLVM version 5.0 (clang-500.2.76) (based on LLVM 3.3svn)
Target: x86_64-apple-darwin13.0.0
Thread model: posix
You need to install the Command Line Developer Tools. Just open Terminal and type up a command that requires it -- for instance, git, gcc or make. Or use the following command:
$ xcode-select --install
You'll see an alert like this:
Just click Install and that's it. As of OS X 10.9, there's no longer need to install Xcode for Ruby development.
Credit for the steps and picture goes to Daniel Kehoe in his latest guide: http://railsapps.github.io/installrubyonrails-mac.html
I had the same problem which I have now been able to solve.
The problem for me was that I had updated to the latest version of Xcode through the appstore but hadn't actually opened the application to complete the install. So here's what solved it for me:
- Updated Xcode
- Opened Xcode application
- Accepted license agreement
- Installed rails
Hope it works for you too.
It wasn't working for me even when I reinstalled xcode and the command line tools for mavericks.
But after that, I just did a bundle update and, for some reason, it worked.
I think I had the same issues. I updated the xcode and open xcode to accept licence aggrement. Then it worked fine as far as I can remember.
来源：https://stackoverflow.com/questions/19580685/installing-rails-on-mavericks