Re: [Haskell-cafe] Hackage on Linux

On Tue, Aug 24, 2010 at 12:18, Joachim Breitner wrote:

Hi,

Am Dienstag, den 24.08.2010, 09:30 +0100 schrieb Magnus Therning:

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On Tue, Aug 24, 2010 at 06:50, Mathew de Detrich wrote:

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- in some situations doing a general update with arch (through clyde or packer)  breaks ghc (last time it happened packer tried to uninstall/update arch packages which failed because those packages had dependencies. The files got removed but since unregister failed ghc thought they still existed)

This is arguably an error in the Arch packages.  The dependencies aren't quite as strict as they really should be.  I've taken the approach of never letting pacman update any haskell-* package.  Instead I do a small song-and-dance where I first remove the packages in question, and any package that depends on them, then I re-install what I just removed.

In Debian, this cannot happen any more, as libraries are tied to the packages of their dependencies via the ABI hash used by ghc. (If I am correctly understanding the symptoms). So using apt-get upgrade will never break any Debian-installed packages.

Yes, I've argued for a Debian-style policy for dependencies in Arch, but apparently people don't find it worth it. I'm not sure whether it'd even be possible to do the same thing for packages from AUR though, which is where most of the Hackage packages are. /M -- Magnus Therning                        (OpenPGP: 0xAB4DFBA4) magnus＠therning．org          Jabber: magnus＠therning．org http://therning.org/magnus         identi.ca|twitter: magthe