报错如下:
xcrun: error: active developer path ("/Applications/Xcode6.app/Contents/Developer") does not exist, use `xcode-select --switch path/to/Xcode.app` to specify the Xcode that you wish to use for command line developer tools (or see `man code-select`)
因为我安装了两个版本 XCode ,又升级了系统。
解决方案:sudo xcode-select-switch/Applications/Xcode.app/Contents/Developer