X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FTcTyClsDecls.lhs;h=27476db02f73a23c90bbc2c52908e581c38d3ce9;hb=76293b141bba4c15a6fd619dd980502e98614790;hp=5101ab316405fe829a1947ec2c8270f3ea5b10a3;hpb=711e4d7a4d65472a3a1fb35bcad8e1c9a109c728;p=ghc-hetmet.git

diff --git a/ghc/compiler/typecheck/TcTyClsDecls.lhs b/ghc/compiler/typecheck/TcTyClsDecls.lhs
index 5101ab3..27476db 100644
--- a/ghc/compiler/typecheck/TcTyClsDecls.lhs
+++ b/ghc/compiler/typecheck/TcTyClsDecls.lhs
@@ -25,11 +25,11 @@ import TcMonad
 import TcEnv		( TcEnv, RecTcEnv, TcTyThing(..), TyThing(..), TyThingDetails(..),
 			  tcExtendKindEnv, tcLookup, tcExtendGlobalEnv,
 			  isLocalThing )
-import TcTyDecls	( tcTyDecl, kcConDetails, checkValidTyCon )
-import TcClassDcl	( tcClassDecl1, checkValidClass )
+import TcTyDecls	( tcTyDecl, kcConDetails )
+import TcClassDcl	( tcClassDecl1 )
 import TcInstDcls	( tcAddDeclCtxt )
 import TcMonoType	( kcHsTyVars, kcHsType, kcHsLiftedSigType, kcHsContext, mkTyClTyVars )
-import TcMType		( newKindVar, zonkKindEnv )
+import TcMType		( newKindVar, zonkKindEnv, checkValidTyCon, checkValidClass )
 import TcUnify		( unifyKind )
 import TcType		( Type, Kind, TcKind, mkArrowKind, liftedTypeKind, zipFunTys )
 import Type		( splitTyConApp_maybe )
@@ -334,6 +334,9 @@ buildTyConOrClass dflags is_rec kenv rec_vrcs  rec_details
 	tycon = mkAlgTyCon tycon_name tycon_kind tyvars ctxt argvrcs
 			   data_cons sel_ids
 			   flavour is_rec gen_info
+	-- It's not strictly necesary to mark newtypes as
+	-- recursive if the loop is broken via a data type.
+	-- But I'm not sure it's worth the hassle of discovering that.
 
 	gen_info | not (dopt Opt_Generics dflags) = Nothing
 		 | otherwise = mkTyConGenInfo tycon sys_names