Xcode 4.3インストール後にgit diffしたらこんなエラーが出た。
$ git diff HEAD
xcode-select: Error: No Xcode folder is set. Run xcode-select -switch
Error: /usr/bin/xcode-select returned unexpected error.
external diff died, stopping at hoge.rb.
以下コマンドを実行すればOK
$ sudo xcode-select -switch /Applications/Xcode.app/Contents/Developer
