Oh, this is irritating. The problem is we recently updated Cabal the library to get rid of InstalledPackageInfo_ (so there is only InstalledPackageInfo now) but it looks like in some situations cabal-install can be compiled with an old version of Cabal (as is happening to you). I suppose an appropriate remedy is to bump the Cabal library dependency in cabal-install so we don't attempt to use the old Cabal; alternately we could preprocessor macro to make it work in both cases.
Edward Excerpts from Oleg Grenrus's message of 2015-08-19 07:46:56 -0700: > I tried to fix compilation of Cabal using Cabal HEAD. It’s trivial patch: > > https://github.com/phadej/cabal/commit/525e0680505c74f42a321e55b357a27222790628 > > but it breaks build on every other released GHC: > > https://travis-ci.org/phadej/cabal/builds/76288656 > > — > > The original issue GHC-7.11 complained was: > > Distribution/Client/Types.hs:71:10: error: > Illegal instance declaration for > ‘PackageFixedDeps InstalledPackageInfo’ > (All instance types must be of the form (T t1 ... tn) > where T is not a synonym. > Use TypeSynonymInstances if you want to disable this.) > In the instance declaration for > ‘PackageFixedDeps InstalledPackageInfo’ > > So I had to add TypeSynonymInstances and FlexibleInstances > > And also had to change import of InstalledPackageInfo(exposed) in Haddock > module. > > — > > At this point I’m really confused. I cannot find ‘InstalledPackageInfo_’ > symbol anywhere. Can someone explain what happens? _______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs