最近系统升级到macOS Big Sur(11.0.1)之后，系统报告如下错误：
$ brew upgrade ........................................... ==> Upgrading 5 outdated packages: tomcat 9.0.39 -> 9.0.40 gradle 6.7 -> 6.7.1 opencv 4.5.0_3 -> 4.5.0_4 vtk 9.0.1_1 -> 9.0.1_2 imagemagick 7.0.10-38 -> 7.0.10-39 ==> Upgrading tomcat 9.0.39 -> 9.0.40 ==> Downloading https://www.apache.org/dyn/closer.lua?path=tomcat/tomcat-9/v9.0. ==> Downloading from https://mirror.bit.edu.cn/apache/tomcat/tomcat-9/v9.0.40/bi ######################################################################## 100.0% Error: Your CLT does not support macOS 11.0. It is either outdated or was modified. Please update your CLT or delete it if no updates are available. Error: An exception occurred within a child process: SystemExit: exit
解决方案如下：
$ sudo rm -rf /Library/Developer/CommandLineTools $ sudo xcode-select --install