Haddock fails with "Module defined in multiple files"
Haddock fails to cooperate with OS X clang CPP:
<no location info>: module ‘pkgid-pkgversion:Main’ is defined in multiple files: dist/build/tmp-#####/Stuff
A workaround is to pass
cabal-install from bootstrapping, unless
--no-doc is specified.
The original Haddock ticket and the corresponding Cabal issue were both closed as invalid, but there appears to be no GHC ticket to track the underlying cause. http://trac.haskell.org/haddock/ticket/284 https://github.com/haskell/cabal/issues/1740