id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
2404	GHCi :r does not reset imported class instances	MartijnVanSteenbergen		"Have a module contain:

{{{
import Control.Monad.Error ()

fromError :: Either String a -> a
fromError = either error id

boom = fromError (return 'x')
}}}

and load in it GHCi. Remove the first line (import ...) and reload. GHCi compiles happily, but then evaluating boom gives:

During interactive linking, GHCi couldn't find the following symbol:
  mtlzm1zi1zi0zi0_ControlziMonadziErrorziClass_zdf2_closure

GHCi should instead produce a compiler error on reloading."	bug	closed	normal		Compiler	6.8.2	duplicate			MacOS X	x86		Unknown