message: Use `gnu-tar` on macos
diff: @@ -110,6 +110,9 @@ jobs:
  - name: Set up dependencies for Mac OS
  run: |
  brew install automake
  + # using gnu-tar is a workaround for https://github.com/actions/cache/issues/403
  + brew install gnu-tar
  + echo PATH="/usr/local/opt/gnu-tar/libexec/gnubin:$PATH" >> $GITHUB_ENV
  if: matrix.os == 'macos-latest' || matrix.os == 'macos-11.0'
  - uses: actions/cache@v2
  with:
  