Hi, I think some recent change might have brought following problem up. installed-pkg-config has some fields escaped when they have spaces (or commas as Thomas showed me in irc.) The token is quoted using Prelude.Show. In case of haddock-interfaces, Cabal actually asks this information back when using haddock to generate docs. ghc-pkg doesn't touch the fields in any way. However, System.Process (or Cabal's own layer) adds quoting for parameters as well, which leads to haddock calling openBinaryFile with a FilePath that contains quotes - and dies horribly. This happens as a rule in Windows when generating docs for package that depends on package that has it's docs installed to a path with spaces on it. Normally ghc is installed to a path with no spaces on it, and these problems don't come up before installing few extra packages with Cabal. Is the right fix to make Cabal unquote the fields it receives from ghc-pkg, or is there some more complex problem lurking around? Best regards, Esa