1 files changed, 2 insertions, 4 deletions
diff --git a/compiler/specialise/Specialise.hs b/compiler/specialise/Specialise.hs
index ed2ae073e9..3434172de2 100644
--- a/compiler/specialise/Specialise.hs
+++ b/compiler/specialise/Specialise.hs
@@ -5,6 +5,7 @@
 -}
 
 {-# LANGUAGE CPP #-}
+{-# LANGUAGE DeriveFunctor #-}
 {-# LANGUAGE ViewPatterns #-}
 module Specialise ( specProgram, specUnfolding ) where
 
@@ -2530,7 +2531,7 @@ deleteCallsFor bs calls = delDVarEnvList calls bs
 ************************************************************************
 -}
 
-newtype SpecM a = SpecM (State SpecState a)
+newtype SpecM a = SpecM (State SpecState a) deriving (Functor)
 
 data SpecState = SpecState {
                      spec_uniq_supply :: UniqSupply,
@@ -2538,9 +2539,6 @@ data SpecState = SpecState {
                      spec_dflags :: DynFlags
                  }
 
-instance Functor SpecM where
-    fmap = liftM
-
 instance Applicative SpecM where
     pure x = SpecM $ return x
     (<*>) = ap