[Nix-dev] Haskell packages in the binary cache broken?

[Jan Malakhovski]

Hello all,

I'm running x86_64 system with ghc 7.4.2.

I noticed quite a while ago that some recently updated Haskell
packages failed to build on my machine. The odd thing was that they
installed just fine from the binary cache (after they appeared there)
and with cabal-dev.

E.g. when building git-annex locally with nix with MissingH package
installed from the binary cache it reported some wild errors about not
finding some functions that were supposed to be in MissingH.

A couple of git pulls from nixpkgs back, cabal reported
containers-<ghc-version>-<hash> installed from the binary cache to be
broken.

Ditto for ghc-mod package.

The "solution" I found was to make a "noop" change to
pkgs/build-support/cabal/default.nix to have all haskell packages
rebuild without the cache. I saw cabal saying something weird about
ghc package database on the way, but it built just fine.

Just to be sure that it is not the hardware to blame, I built my
desktop's configuration.nix on the other machine and saw exactly the
same things happen.

Cheers,
  Jan Malakhovski