1. Summarise the issue (what were doing, what went wrong?)
darcs cannot build with GHC 8.0.2-rc2, which uses directory 1.3 since
the darcs.cabal file's upper bound on directory is < 18.104.22.168.
2. What behaviour were you expecting instead?
failed build in a Cabal sandbox
3. What darcs version are you using? (Try: darcs --exact-version)
4. What operating system are you running?
macOS 10.12 with Homebrew GHC (which is currently 8.0.2-RC2 on Sierra)