[Haskell-cafe] Re: Unable to install packages

[Albert Y. C. Lai]

On 10-11-29 03:15 PM, Albert Y. C. Lai wrote:
> cabal install --global binary
> apt-get install libghc6-binary-dev
>
> They are the same version (at the time of writing, and assume Ubuntu
> 10.10) and they will fight for the unique throne of "binary-0.5.0.2" in
> the metadata.

Oh bother, Debian/Ubuntu's packages are even more treacherous. They 
circumvent the uniqueness checks of ghc-pkg register. They just smuggle 
records into /var/lib/ghc-6.12.1/package.conf.d and call ghc-pkg 
recache. This procedure allows both binary-0.5.0.2 instances to be 
recorded, both as global. Ironically, ghc-pkg check does not see a problem.

But this is more corruption, not less:

> cabal install --global maccatcher
> (this brings in binary)
> apt-get install libghc6-agda-dev
> (this brings in libghc6-binary-dev)

The same problem remains. When you finally try to use binary, GHC still 
picks one instance only. Depend on luck, one of maccatcher and agda is 
hosed.