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module T22761 where
import T22761a
newtype Mod m = Mod m deriving Num
gcdExt :: Integer -> (Integer, Integer)
gcdExt x = go 0 x
where
go !_ 0 = (1, 1)
go r _ = go r r
pow :: (Num m) => Mod m -> Mod m
pow x = x*x*x
{-# NOINLINE [1] pow #-}
{-# RULES
"powMod/3/Int" forall x. pow x = x*x*x
#-}
-- GHC puts `boo1` after `wom1` (since they don't appear connected)
-- Then { wom1 = foo True } rewrites to { wom1 = boo False }
-- so we need to do glomming. And that triggers the bug
-- in the RULE for `pow`!
--
-- wom2/boo2 are there to still elicit the bug if
-- GHC reverses its default ordering
{-# RULES
"wombat1" foo True = boo1 False
#-}
wom1 = foo True
boo1 x = x
{-# RULES
"wombat2" foo True = boo2 False
#-}
boo2 x = x
wom2 = foo True
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