[Haskell-beginners] Missing or recursive dependencies

[Lyndon Maydwell]

The thing is that ghc-pkg check returns nothing.

On Thu, Sep 2, 2010 at 5:44 PM, Daniel Fischer <daniel.is.fischer at web.de> wrote:
> On Thursday 02 September 2010 11:31:01, Lyndon Maydwell wrote:
>> Hi beginners.
>>
>> I'm getting an odd problem quite a lot recently:
>>
>> ghc -fglasgow-exts --make -O2 -W X.hs -v -o X
>>
>> package Cabal-1.8.0.6-ec9be469687b5a514f4b7e8e2b8343c7 is shadowed by
>> package Cabal-1.8.0.6-c995b90190c27e1dfa2ab3d5434fabef
>
> You have two versions of Cabal-1.8.0.6, probably you should unregister the
> one in the user-db.
>
> Anyway, run ghc-pkg check first. Fix what that reports as broken by
> unregistering/reinstalling.
> Since what is shown below all directly or indirectly traces to ghc-6.12.3,
> which depends on Cabal-1.8.0.6, your two versions of that are probably the
> root cause, so I'd start with Cabal.
>
>> package QuickCheck-2.1.1.1-c7435cb0d5b5de72fe9540c48335606d is
>> unusable due to missing or recursive dependencies:
>>   ghc-6.12.3-66a382195c8a71849653439b67021fd1
>> package bin-package-db-0.0.0.0-0dffb74a73bb78b5dc02ca941bbcbea0 is
>> unusable due to missing or recursive dependencies:
>>   Cabal-1.8.0.6-ec9be469687b5a514f4b7e8e2b8343c7
>> package category-extras-0.53.5-ee54cd5c810a6c004a1b7a276d0e0076 is
>> unusable due to missing or recursive dependencies:
>>   ghc-6.12.3-66a382195c8a71849653439b67021fd1
>> package comonad-random-0.1.2-897a5da683d269c3b2db3e03ac43279b is
>> unusable due to missing or recursive dependencies:
>>   category-extras-0.53.5-ee54cd5c810a6c004a1b7a276d0e0076
>> ...
>>
>> I've asked on irc, and the consensus is that something is very wrong,
>> however we weren't able to diagnose the cause. It would probably be
>> worth looking at on-list for future reference.
>>
>> Does anyone have any ideas?
>
>