[Haskell-cafe] impoosible dependencies

[Kevin Quick]

On Wed, 20 Apr 2011 15:18:21 -0700, Rogan Creswick <creswick at gmail.com> wrote:

> On Wed, Apr 20, 2011 at 2:51 PM, Kevin Quick <quick at sparq.org> wrote:
>> $ cabal update
>> $ cabal install hakyll
>> Resolving dependencies...
>> cabal: dependencies conflict: ghc-6.12.3 requires unix ==2.4.0.2 however
>> unix-2.4.0.2 was excluded because ghc-6.12.3 requires unix ==2.4.1.0
>> $
>>
>> Any advice (other than upgrading to 7.0.3, which is not an option at the
>> moment)?
>
> You can run the build with verbose output (--verbose=3) and get more
> details about why the impossible dependencies were required,

No joy: hakyll itself requires unix 2.4, so the following are discarded:  unix-2.0, 2.2.0.0, 2.3.0.0, 2.3.1.0, 2.3.2.0,

However, that's the only unix discard before the error occurs somewhat later on, only now the error is not with unix but with array (which is not discarded by anything):

...

selecting text-0.11.0.5 (installed or hackage) and discarding text-0.11.0.0,
0.11.0.1, 0.11.0.2, 0.11.0.3, 0.11.0.4, 0.11.0.6 and 0.11.0.7
selecting deepseq-1.1.0.2 (installed or hackage) and discarding
deepseq-1.1.0.0 and 1.1.0.1
selecting QuickCheck-2.4.0.1 (installed or hackage) and discarding
QuickCheck-2.1, 2.1.0.1, 2.1.0.2, 2.1.0.3, 2.1.1, 2.1.1.1, 2.1.2, 2.2, 2.3,
2.3.0.1, 2.3.0.2 and 2.4
selecting
cabal: dependencies conflict: ghc-6.12.3 requires array ==0.3.0.2 however
array-0.3.0.2 was excluded because ghc-6.12.3 requires array ==0.3.0.1
$

Its starting to look like there's something very wrong with cabal databases.  My first thought is to remove my local version, but I'm hesitant because I do have other haskell work I'm in progress on that isn't broken and I don't want to break it.  :-)

> or you
> can build your application (whatever relies on hakyll) with cabal-dev
> -- I've been able to build hakyll that way on my machine with
> ghc-6.12.3, so I suspect there is some unexpected dependency in your
> local package db that is causing cabal to make a series of undesirable
> version selections.
>
> --Rogan

No joy there either.  There were some preliminary package version complaints that I tried to resolve, but the end result is:

$ cabal install cabal-dev
Resolving dependencies...
[1 of 1] Compiling Main             ( /tmp/cabal-dev-0.7.4.113115/cabal-dev-0.7.4.1/Setup.hs, /tmp/cabal-dev-0.7.4.113115/cabal-dev-0.7.4.1/dist/setup/Main.o )

/tmp/cabal-dev-0.7.4.113115/cabal-dev-0.7.4.1/Setup.hs:7:47:
     Warning: In the use of `buildVerbose'
              (imported from Distribution.Simple.Setup):
              Deprecated: "Use buildVerbosity instead"
Linking /tmp/cabal-dev-0.7.4.113115/cabal-dev-0.7.4.1/dist/setup/setup ...
cabal: Error: some packages failed to install:
cabal-dev-0.7.4.1 failed during the configure step. The exception was:
ExitFailure 11
$

With --verbose=3 this appears to be post-link running cabal-dev itself:

$ cabal install cabal-dev --verbose=3
...

*** Deleting temp files:
Deleting:
link: linkables are ...
LinkableM (Wed Apr 20 16:14:58 MST 2011) main:Main
    [DotO /tmp/cabal-dev-0.7.4.113193/cabal-dev-0.7.4.1/dist/setup/Main.o]
Linking /tmp/cabal-dev-0.7.4.113193/cabal-dev-0.7.4.1/dist/setup/setup ...
*** Linker:
...[verbose GCC output elided]...
rtend.o /nix/store/l8x3fdy1r6zf441vnqa87lzsvxrjbdz9-glibc-2.11.1/lib/crtn.o
link: done
*** Deleting temp files:
Deleting:
*** Deleting temp dirs:
Deleting: /tmp/ghc13224_0
/tmp/cabal-dev-0.7.4.113193/cabal-dev-0.7.4.1/dist/setup/setup configure
--verbose=3 --ghc --prefix=/home/kquick/.cabal --user --flags=-build-tests
--flags=-no-cabal-dev --extra-include-dirs=/home/kquick/.nix-profile/include
--extra-lib-dirs=/home/kquick/.nix-profile/lib --constraint=Cabal ==1.10.1.0
--constraint=HTTP ==4000.1.1 --constraint=base ==4.2.0.2
--constraint=bytestring ==0.9.1.9 --constraint=directory ==1.0.1.1
--constraint=filepath ==1.1.0.4 --constraint=mtl ==2.0.1.0
--constraint=network ==2.3.0.2 --constraint=pretty ==1.0.1.1
--constraint=process ==1.0.1.3 --constraint=tar ==0.3.1.0 --constraint=zlib
==0.5.3.1
cabal: Error: some packages failed to install:
cabal-dev-0.7.4.1 failed during the configure step. The exception was:
ExitFailure 11
$


-- 
-KQ