diff --git a/ghc/compiler/typecheck/TcDeriv.lhs b/ghc/compiler/typecheck/TcDeriv.lhs
index 08d28dc95cc66b9c0cb0ad753de8259430913668..cd59646895f96b21e077a5d3e79ace27413b5e30 100644
--- a/ghc/compiler/typecheck/TcDeriv.lhs
+++ b/ghc/compiler/typecheck/TcDeriv.lhs
@@ -309,12 +309,13 @@ makeDerivEqns this_mod tycons
       = case chk_out clas tycon of
 	   Just err ->  addErrTc err				`thenNF_Tc_` 
 			returnNF_Tc Nothing
-	   Nothing  ->  newDFunName this_mod clas tyvar_tys locn `thenNF_Tc` \ dfun_name ->
+	   Nothing  ->  newDFunName this_mod clas [ty] locn `thenNF_Tc` \ dfun_name ->
 			returnNF_Tc (Just (dfun_name, clas, tycon, tyvars, constraints))
       where
 	clas_key  = classKey clas
-	tyvars    = tyConTyVars tycon	-- ToDo: Do we need new tyvars ???
+	tyvars    = tyConTyVars tycon
 	tyvar_tys = mkTyVarTys tyvars
+	ty	  = mkTyConApp tycon tyvar_tys
 	data_cons = tyConDataCons tycon
 	locn	  = getSrcLoc tycon
 
diff --git a/ghc/compiler/typecheck/TcModule.lhs b/ghc/compiler/typecheck/TcModule.lhs
index 53de0773a5992a83932cd0b918c26398f8b9e617..7edd70c38b1b9df2d0d2d71ef68d98c5b51d59ac 100644
--- a/ghc/compiler/typecheck/TcModule.lhs
+++ b/ghc/compiler/typecheck/TcModule.lhs
@@ -46,7 +46,7 @@ import Module           ( Module )
 import Name		( Name, isLocallyDefined, 
 			  toRdrName, nameEnvElts, lookupNameEnv, 
 			)
-import TyCon		( tyConGenInfo, isClassTyCon )
+import TyCon		( tyConGenInfo )
 import Maybes		( thenMaybe )
 import Util
 import BasicTypes       ( EP(..), Fixity )