$ npm install -g webpack
npm WARN deprecated urix@0.1.0: Please see https://github.com/lydell/urix#deprecated
npm WARN deprecated resolve-url@0.2.1: https://github.com/lydell/resolve-url#deprecated
npm WARN deprecated chokidar@2.1.8: Chokidar 2 will break on node v14+. Upgrade to chokidar 3 with 15x less dependencies.
npm WARN deprecated fsevents@1.2.13: fsevents 1 will break on node v14+ and could be using insecure binaries. Upgrade to fsevents 2.
/usr/local/bin/webpack -> /usr/local/lib/node_modules/webpack/bin/webpack.js

> fsevents@1.2.13 install /usr/local/lib/node_modules/webpack/node_modules/watchpack-chokidar2/node_modules/fsevents
> node install.js

No receipt for 'com.apple.pkg.CLTools_Executables' found at '/'.

No receipt for 'com.apple.pkg.DeveloperToolsCLILeo' found at '/'.

No receipt for 'com.apple.pkg.DeveloperToolsCLI' found at '/'.

gyp: No Xcode or CLT version detected!
gyp ERR! configure error 
gyp ERR! stack Error: `gyp` failed with exit code: 1
gyp ERR! stack     at ChildProcess.onCpExit (/usr/local/lib/node_modules/npm/node_modules/node-gyp/lib/configure.js:351:16)
gyp ERR! stack     at ChildProcess.emit (events.js:315:20)
gyp ERR! stack     at Process.ChildProcess._handle.onexit (internal/child_process.js:276:12)
gyp ERR! System Darwin 19.4.0
gyp ERR! command "/usr/local/Cellar/node/14.3.0_1/bin/node" "/usr/local/lib/node_modules/npm/node_modules/node-gyp/bin/node-gyp.js" "rebuild"
gyp ERR! cwd /usr/local/lib/node_modules/webpack/node_modules/watchpack-chokidar2/node_modules/fsevents
gyp ERR! node -v v14.3.0
gyp ERR! node-gyp -v v5.1.0
gyp ERR! not ok 
npm WARN notsup Unsupported engine for watchpack-chokidar2@2.0.0: wanted: {"node":"<8.10.0"} (current: {"node":"14.3.0","npm":"6.14.4"})
npm WARN notsup Not compatible with your version of node/npm: watchpack-chokidar2@2.0.0

+ webpack@4.43.0
added 348 packages from 210 contributors in 12.778s

sudo rm -rf $(xcode-select -print-path)
xcode-select --install
/usr/sbin/pkgutil --packages | grep CLTsudo npm install -g node-gyp