[Haskell-cafe] Cabal problem, broken packages?

[Tom Ellis]

On Thu, Sep 15, 2022 at 05:33:06PM +0100, Tom Ellis wrote:
> On Thu, Sep 15, 2022 at 06:09:33PM +0200, Volker Wysk wrote:
> > Am Donnerstag, dem 15.09.2022 um 17:47 +0200 schrieb Mikolaj Konarski:
> > > This may be caused by some cabal.project lying around
> > > (e.g., in the directory you are in when you are installing, but also
> > > in any parent directory) or by .ghc.environment.arch-os-version
> > > files lying around
> > > 
> > > https://ghc.gitlab.haskell.org/ghc/doc/users_guide/packages.html#package-environments
> > 
> > I don't have a cabal.project or .ghc.environment.arch-os-version lying
> > around. However, I've found ~/.ghc/x86_64-linux-8.8.4/environments/default,
> > which contains this:
> 
> GHC 8.8.4 depends on directory 1.3.6.0, therefore the GHC API package,
> ghc, does too as mentioned in the original error message:
> 
> 
> [__1] rejecting: ghc-8.8.4/installed-8.8... (conflict: directory==1.3.7.1, ghc
> => directory==1.3.6.0/installed-1.3...)
> 
> 
> and can be verified at:
> 
> https://gitlab.haskell.org/ghc/ghc/-/wikis/commentary/libraries/version-history
> 
> 
> However, you have got an environment file that requires ghc-8.8.4 and
> directory-1.3.7.1 at the same time.  Something's funny about that
> because it's impossible to satisfy and I'm not sure how it could have
> happened in the first place.  Perhaps some cabal expert can weigh in.

In the hope that a cabal expert can explain this behaviour I have
opened as issue:

https://github.com/haskell/cabal/issues/8473