cabal sdist trouble with GHC from head

[Sven Panne]

2014-10-22 15:16 GMT+02:00 Sven Panne <svenpanne at gmail.com>:
> Does anybody have a clue what's going wrong at the sdist step here?
>
>    https://travis-ci.org/haskell-opengl/OpenGLRaw/jobs/38707011#L104
>
> This only happens with a GHC from head, a build with GHC 7.8.3 is fine:
>
>    https://travis-ci.org/haskell-opengl/OpenGLRaw/jobs/38707010
>
> Any help highly appreciated...

I would really need some help here, even adding a few more diagnostic
things to the Travis CI configuration didn't give me a clue what's
going wrong:

   https://travis-ci.org/haskell-opengl/OpenGLRaw/jobs/38813449#L110

I totally fail to understand why Cabal's sdist step works with every
released compiler, but not with a GHC from head. I don't even know if
this is a Cabal issue or a GHC issue. The relevant part from the
Travis CI log is:

   ...
   cabal-1.18 sdist --verbose=3
   creating dist/src
   creating dist/src/sdist.-3586/OpenGLRaw-1.5.0.0
   Using internal setup method with build-type Simple and args:
   ["sdist","--verbose=3","--builddir=dist","--output-directory=dist/src/sdist.-3586/OpenGLRaw-1.5.0.0"]
   cabal-1.18: dist/setup-config: invalid argument
   The command "cabal-1.18 sdist --verbose=3" exited with 1.
   ...

As can be seen from the log, dist/setup-config is there and can be accessed.

Confused,
   S.