Fix AppVeyor cache failure (#456)
Fix AppVeyor cache failure (#456)


sdiehl/ghc,bgamari/shaking-up-ghc,snowleopard/shaking-up-ghc,sdiehl/ghc,sdiehl/ghc,snowleopard/hadrian,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc