Xcode命令行工具可以从这里下载:https://developer.apple.com/downloads/index.action#

2014年4月版直接下载链接(适合想马上上手的开发人员) https://developer.apple.com/downloads/download.action?path=Developer_Tools/command_line_tools_os_x_mavericks_for_xcode__april_2014/command_line_tools_for_osx_mavericks_april_2014.dmg

如果你在尝试使用命令行工具时查看“控制台”，你会发现实际上有一个到Mountain Lion命令行工具的“非官方”链接!

所以试试吧:

http://adcdownload.apple.com/ios/ios_simulator__resigned/cltools_mountainliondp2_march12.dmg

这是我的控制台日志:

01/04/2012 15:41:54.258 Xcode: [MT] DVTDownloadable: Download failed. Downloadable: {
    dependencies =     (
    );
    fileSize = 141452226;
    identifier = "Xcode.CLTools.10.8";
    name = "Command Line Tools";
    source = "http://adcdownload.apple.com/ios/ios_simulator__resigned/cltools_mountainliondp2_march12.dmg";
    userInfo =     {
        ActivationPredicate = "$MAC_OS_X_VERSION >= '10.8.0' && $MAC_OS_X_VERSION < '10.9.0'";
        InstallPrefix = "/";
        InstalledIfAllSHA1SumsMatch =         {
            "/usr/bin/clang" = 600c35175775a6002452a88f17e00c570cd2e2d0;
        };
        Summary = "Before installing, note that from within Terminal you can use the XCRUN tool to launch compilers and other tools embedded within the Xcode application. Use the XCODE-SELECT tool to define which version of Xcode is active.  Type \"man xcrun\" from within Terminal to find out more.\n\nDownloading this package will install copies of the core command line tools and system headers into system folders, including the LLVM compiler, linker, and build tools.";
        "Xcode.SDKs" =         (
        );
    };
    version = "1.1.1";
}. Error: Error Domain=NSCocoaErrorDomain Code=3840 "The data couldn’t be read because it has been corrupted." (Encountered unknown ampersand-escape sequence at line 18) UserInfo=0x401bc8e60 {NSDebugDescription=Encountered unknown ampersand-escape sequence at line 18, kCFPropertyListOldStyleParsingError=The data couldn’t be read because it has been corrupted.}

Xcode Command Line Tools can be installed as a side effect of running git --version in Terminal without Git installed. You will be prompted to install the tools as a requirement for running Git. Apple ships a binary of git with the Command Line tools. This is confirmed on the Git for Mac Download page. This seems like a valid option considering that Homebrew requires the Command Line tools to install Git as well according to another SO post. Otherwise, the previous answers are the most direct methods of install the tools.

除了从Apple安装命令行工具的“官方”版本，你也可以从这里安装Kenneth的版本:

https://github.com/kennethreitz/osx-gcc-installer

如果你所追求的只是命令行工具，它甚至不需要XCode。

通过将我的Mac更新到最新的Mac OS(即Big Sur)，一切都分解为重复要求安装Xcode-select。

这可能看起来很奇怪，但我通过重新安装并更新到最新的Xcode解决了这个问题。

这只是我解决问题的经验。

至于大sur..

sudo rm -rf /Library/Developer/CommandLineTools
sudo xcode-select --install

感谢自制啤酒维护者把这有用的消息在酿造医生