Interesting: in the ghc-devs discussion, Duncan talks about a cabal-lib and a cabal-build-simple split (http://www.haskell.org/pipermail/ghc-devs/2013-March/000821.html). That would solve my problem nicely (GHC could depend on cabal-lib only, that wouldn't have to change as often as cabal-build-simple). I don't see a trace of that split in 1.18, anybody knows if it's still on the map?
And thanks everybody for the contributions, it looks I'm not the only one that had thought about that issue...

JP


On Fri, Sep 6, 2013 at 4:32 PM, Herbert Valerio Riedel <hvr@gnu.org> wrote:
On 2013-09-06 at 15:13:58 +0200, Yuri de Wit wrote:
> I spent some time looking into the touch points between ghc and cabal in
> the past, and the first oddity i saw was a direct dependency from ghc to
> the cabal sources. After taking a closer look it seems that ghc shares some
> common, low level modules with cabal that didnt seem to justify the whole
> dependency.
>
> The right solution, imho, is to review these dependencies and move the low
> level ones out into a separate package that is shared by both ghc and cabal
> and that will rarely change. The direct side effect of this is that ghc
> would not be tied directly to a specific cabal version and you would
> not have to deal with this issue.

[...]

fyi, a similiar/related discussion took place few months ago on ghc-devs:

 http://www.haskell.org/pipermail/ghc-devs/2013-March/000800.html

hth,
  hvr



--
JP Moresmau
http://jpmoresmau.blogspot.com/