Resolving dependencies...
Error: cabal: Could not resolve dependencies:
[__0] next goal: ghc-prim (user goal)
[__0] rejecting: ghc-prim-0.10.0 (only already installed instances can be
used)
[__0] rejecting: ghc-prim-0.9.0, ghc-prim-0.8.0, ghc-prim-0.7.0,
ghc-prim-0.6.1, ghc-prim-0.5.3, ghc-prim-0.5.2.0, ghc-prim-0.5.1.1,
ghc-prim-0.5.1.0, ghc-prim-0.5.0.0, ghc-prim-0.4.0.0, ghc-prim-0.3.1.0
(constraint from user target requires ==0.10.0)
[__0] fail (backjumping, conflict set: ghc-prim)
After searching the rest of the dependency tree exhaustively, these were the
goals I've had most trouble fulfilling: ghc-prim