id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
1012	ghc panic with mutually recursive modules and template haskell	guest		"When compiling the files below using ghc --make Main.hs I get the following error:
{{{
[1 of 5] Compiling ModuleA[boot]    ( ModuleA.hs-boot, nothing )
[2 of 5] Compiling ModuleC          ( ModuleC.hs, ModuleC.o )
[3 of 5] Compiling ModuleB          ( ModuleB.hs, ModuleB.o )
Loading package base ... linking ... done.
Loading package template-haskell ... linking ... done.
ghc-6.6: panic! (the 'impossible' happened)
  (GHC version 6.6 for powerpc-apple-darwin):
        Maybe.fromJust: Nothing
}}}


ModuleA.hs:
{{{
module ModuleA where

import ModuleB
}}}

ModuleA.hs-boot:
{{{
module ModuleA where
}}}

ModuleB.hs:
{{{
{-# OPTIONS -fth #-}
module ModuleB where

import ModuleC

$(nothing)
}}}

ModuleC.hs:
{{{
module ModuleC where

import Language.Haskell.TH

import {-# SOURCE #-} ModuleA

nothing = return [] :: Q [Dec]
}}}

Main.hs:
{{{
module Main.hs

import ModuleA

main = return ()
}}}"	bug	new	lowest	7.6.2	Template Haskell	6.8.2			leuschner@… ozgurakgun@…	Unknown/Multiple	Unknown/Multiple	None/Unknown	Unknown	TH_import_loop