bug#33922: failing git-annex build

[Ricardo Wurmus]

Hi Kyle,

> I'm seeing the failure below when trying to build git-annex.  Can anyone
> else reproduce this failure?  Any ideas how to resolve it?
>
> --8<---------------cut here---------------start------------->8---
> % git describe
> v0.16.0-400-g4f36d98f7b
>
> % ./pre-inst-env guix build -K --check git-annex
> Utility/Exception.hs:29:1: error:
>     Bad interface file: 
> /gnu/store/qb3knv1h536sdjqc4nfkm3j1l8n7q87a-ghc-exceptions-0.10.0/lib/ghc-8.4.3/exceptions-0.10.0/Control/Monad/Catch.dyn_hi
>         Something is amiss; requested module  
> exceptions-0.10.0:Control.Monad.Catch differs from name found in the 
> interface file exceptions-0.10.0:Control.Monad.Catch (if these names look the 
> same, try again with -dppr-debug)
>    |
> 29 | import Control.Monad.Catch as X hiding (Handler)
>    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

It seems to me that this is a more general problem affecting all of our
Haskell packages.  The configure phase that you didn’t paste should show
that modules are provided by slightly different packages.

The haskell-build-system suffers from non-determinism.  It might just be
limited to the package database files that are generated by ghc-pkg
(where readdir is used and the result isn’t sorted).

I’m opening a bug report for this issue.

-- 
Ricardo