X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcMType.lhs;h=955d45c551c6a07d209d74bbd69161fc2a0e2400;hp=e5ccbd0a34ce08fe48900d94873a7479b4e27d84;hb=c1681a73fa4ca4cf8758264ae387ac09a9e900d8;hpb=9eb79d53316804b4c384b5084825112c48f1bbc4

diff --git a/compiler/typecheck/TcMType.lhs b/compiler/typecheck/TcMType.lhs
index e5ccbd0..955d45c 100644
--- a/compiler/typecheck/TcMType.lhs
+++ b/compiler/typecheck/TcMType.lhs
@@ -694,7 +694,7 @@ checkValidType :: UserTypeCtxt -> Type -> TcM ()
 -- Checks that the type is valid for the given context
 checkValidType ctxt ty
   = traceTc (text "checkValidType" <+> ppr ty)	`thenM_`
-    doptM Opt_GlasgowExts	`thenM` \ gla_exts ->
+    doptM Opt_UnboxedTuples `thenM` \ unboxed ->
     doptM Opt_Rank2Types	`thenM` \ rank2 ->
     doptM Opt_RankNTypes	`thenM` \ rankn ->
     doptM Opt_PolymorphicComponents	`thenM` \ polycomp ->
@@ -729,14 +729,10 @@ checkValidType ctxt ty
 			ForSigCtxt _ -> isLiftedTypeKind actual_kind
 			other	     -> isSubArgTypeKind    actual_kind
 	
-	ubx_tup | not gla_exts = UT_NotOk
-		| otherwise    = case ctxt of
-				   TySynCtxt _ -> UT_Ok
-				   ExprSigCtxt -> UT_Ok
-				   other       -> UT_NotOk
-		-- Unboxed tuples ok in function results,
-		-- but for type synonyms we allow them even at
-		-- top level
+	ubx_tup = case ctxt of
+	              TySynCtxt _ | unboxed -> UT_Ok
+	              ExprSigCtxt | unboxed -> UT_Ok
+	              _                     -> UT_NotOk
     in
 	-- Check that the thing has kind Type, and is lifted if necessary
     checkTc kind_ok (kindErr actual_kind)	`thenM_`
@@ -857,8 +853,8 @@ check_tau_type rank ubx_tup ty@(TyConApp tc tys)
 	}
     
   | isUnboxedTupleTyCon tc
-  = doptM Opt_GlasgowExts			`thenM` \ gla_exts ->
-    checkTc (ubx_tup_ok gla_exts) ubx_tup_msg	`thenM_`
+  = doptM Opt_UnboxedTuples `thenM` \ ub_tuples_allowed ->
+    checkTc (ubx_tup_ok ub_tuples_allowed) ubx_tup_msg	`thenM_`
     mappM_ (check_tau_type (Rank 0) UT_Ok) tys	
 		-- Args are allowed to be unlifted, or
 		-- more unboxed tuples, so can't use check_arg_ty
@@ -867,7 +863,7 @@ check_tau_type rank ubx_tup ty@(TyConApp tc tys)
   = mappM_ check_arg_type tys
 
   where
-    ubx_tup_ok gla_exts = case ubx_tup of { UT_Ok -> gla_exts; other -> False }
+    ubx_tup_ok ub_tuples_allowed = case ubx_tup of { UT_Ok -> ub_tuples_allowed; other -> False }
 
     n_args    = length tys
     tc_arity  = tyConArity tc
@@ -1179,15 +1175,15 @@ instTypeErr pp_ty msg
 \begin{code}
 checkValidInstance :: [TyVar] -> ThetaType -> Class -> [TcType] -> TcM ()
 checkValidInstance tyvars theta clas inst_tys
-  = do	{ gla_exts <- doptM Opt_GlasgowExts
-	; undecidable_ok <- doptM Opt_AllowUndecidableInstances
+  = do	{ undecidable_ok <- doptM Opt_AllowUndecidableInstances
 
 	; checkValidTheta InstThetaCtxt theta
 	; checkAmbiguity tyvars theta (tyVarsOfTypes inst_tys)
 
 	-- Check that instance inference will terminate (if we care)
-	-- For Haskell 98, checkValidTheta has already done that
-	; when (gla_exts && not undecidable_ok) $
+	-- For Haskell 98 this will already have been done by checkValidTheta,
+    -- but as we may be using other extensions we need to check.
+	; unless undecidable_ok $
 	  mapM_ addErrTc (checkInstTermination inst_tys theta)
 	
 	-- The Coverage Condition