Desinstalar XCode

Desinstalação completa do XCode

$ sudo /Developer/Library/uninstall-devtools --mode=all

Desinstale o Unix Development Toolkit do Xcode

$ sudo /Developer/Library/uninstall-devtools --mode=unixdev

Desinstalar apenas a pasta e conteúdo do desenvolvedor Xcode

$ sudo /Developer/Library/uninstall-devtools --mode=xcodedir

Desinstalar o suporte do sistema Xcode

$ sudo /Developer/Library/uninstall-devtools --mode=systemsupport

Fonte osxdaily