id	summary	reporter	owner	description	type	status	priority	milestone	version	resolution	keywords	cc
135	haddock stomps on existing .o and .hi files, breaking package builds	duncan		"For packages using TemplateHaskell haddock generates .o and .hi files. Unfortunately this overwrites existing files produced by the build system and breaks packages. This currently affects several packages that use TemplateHaskell and Cabal.

Cabal can be modified to workaround this problem by telling haddock to use a separate directory for its temp files. A better solution would be for haddock to do this always and automatically. It should never overwrite the user's existing .o and .hi files. It is very surprising behaviour from a documentation tool. (Yes, I know the technical reasons why it does it at the moment, but it is still very surprising).

Related: comments in ticket #101."	defect	closed	major		2.6.0	fixed