[Pkg-haskell-maintainers] Bug#778987: Bug#778987: mismatched versions of cabal-install and Cabal result in build failures

[Sven Bartscher]

> Am 23.02.2015 um 09:32 schrieb Joachim Breitner <nomeata at debian.org>:
> 
> Hi,
> 
> Am Montag, den 23.02.2015, 07:49 +0100 schrieb Sven Bartscher:
>> Making cabal-install depend on the newer version of libghc-cabal-dev,
>> should fix this. It would also spare us from finding errors like this
>> in other packages.
> 
> sounds reasonable. Can you make it so that the cabal-install package
> automatically depends on the right Cabal package, using substvars? A
> manual dependency in debian/control will likely get forgetten.

That should be possible, but as always, there might be unseen problems.
I will look at it, as soon as I’ve got time, but I don’t know when that is.

>> If we decide to do this, we should probably
>> transition to stop shipping cabal together with GHC, since no one will
>> have cabal-install and thus libghc-cabal-dev installed, which defies
>> the reason to have the GHC version of cabal installed.
> 
> That’s not easily possible: ghc (the library) depends on the version of
> Cabal coming with GHC.
> 
> There are plans upstream to change that, but that won’t happen before
> 7.12, see  https://ghc.haskell.org/trac/ghc/ticket/8244 and
> https://ghc.haskell.org/trac/ghc/wiki/CabalDependency