X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcDeriv.lhs;h=65c425d255d1c9522b34585dd3e0d658fdca6a31;hb=1525a5819aa3a6eae8d8b05cfe348a2384da0c84;hp=22168fce6ba67257b6c6f1e04503032ea610444b;hpb=5f0c4f9aa291cdc291fcdc0c4a30fdce1f91230d;p=ghc-hetmet.git

diff --git a/compiler/typecheck/TcDeriv.lhs b/compiler/typecheck/TcDeriv.lhs
index 22168fc..65c425d 100644
--- a/compiler/typecheck/TcDeriv.lhs
+++ b/compiler/typecheck/TcDeriv.lhs
@@ -31,10 +31,10 @@ import RnEnv		( bindLocalNames )
 import HscTypes		( FixityEnv )
 
 import Class		( className, classArity, classKey, classTyVars, classSCTheta, Class )
-import Type		( zipOpenTvSubst, substTheta, pprThetaArrow, pprClassPred )
+import Type		( zipOpenTvSubst, substTheta, pprThetaArrow, pprClassPred, mkTyVarTy )
 import ErrUtils		( dumpIfSet_dyn )
 import MkId		( mkDictFunId )
-import DataCon		( isNullarySrcDataCon, isVanillaDataCon, dataConOrigArgTys )
+import DataCon		( isNullarySrcDataCon, isVanillaDataCon, dataConOrigArgTys, dataConInstOrigArgTys )
 import Maybes		( catMaybes )
 import RdrName		( RdrName )
 import Name		( Name, getSrcLoc )
@@ -568,7 +568,7 @@ mkDataTypeEqn tycon clas
     ordinary_constraints
       = [ mkClassPred clas [arg_ty] 
         | data_con <- tyConDataCons tycon,
-          arg_ty   <- dataConOrigArgTys data_con,
+          arg_ty <- dataConInstOrigArgTys data_con (map mkTyVarTy (tyConTyVars tycon)),
           not (isUnLiftedType arg_ty)	-- No constraints for unlifted types?
         ]
 
@@ -952,7 +952,7 @@ genTaggeryBinds infos
 \begin{code}
 derivingThingErr clas tys tycon tyvars why
   = sep [hsep [ptext SLIT("Can't make a derived instance of"), quotes (ppr pred)],
-	 parens why]
+	 nest 2 (parens why)]
   where
     pred = mkClassPred clas (tys ++ [mkTyConApp tycon (mkTyVarTys tyvars)])