step1、install Xcode

step2、install xcpkg

step3、update xcpkg-formula-repository

xcpkg update

step4、build and install gflags

xcpkg install gflags

xcpkg formula view gflags

{{ formula }}

if the formula of gflags dosn't meet your needs, you can edit it ⤵︎

xcpkg formula edit gflags

after editing, you may want to rebuild this package ⤵︎

xcpkg install gflags