message: AppVeyor: try to clear corrupted cache to mitigate
diff: version: 0.0.0.0.1-branch-{branch}-build-{build}
  clone_depth: 10
  cache:
  - - c:\cygwin-setup-cache
  + - c:\cygwin-setup-cache -> .appveyor.yml
  environment:
  matrix:
  - cygwin_url: https://cygwin.com/setup-x86_64.exe
  