Haddock fails with "Module defined in multiple files"

[Mateusz Kowalczyk]

Hi,

We just got a bug report over at Haddock Trac[1]. What's not mentioned
is that it works fine for the user on GHC 7.6.3 with Haddock 2.13.1. I
can't think of any Haddock changes that could have potentially caused
the reported breakage.

This e-mail is to ask whether any Cabal(-install) devs can think of
anything that might have changed on your end of things that could cause
this before we go off chasing a bug in the wrong project.

I don't follow the changes in cabal (even though I should) so it might
be something really obvious that changed recently that we aren't aware of.

Thanks

[1]: http://trac.haskell.org/haddock/ticket/284

-- 
Mateusz K.