[project @ 2001-11-06 11:02:05 by simonmar]

[ghc-hetmet.git] / ghc / compiler / stgSyn / StgLint.lhs

diff --git a/ghc/compiler/stgSyn/StgLint.lhs b/ghc/compiler/stgSyn/StgLint.lhs
index 72a1ffb..af593eb 100644 (file)
--- a/ghc/compiler/stgSyn/StgLint.lhs
+++ b/ghc/compiler/stgSyn/StgLint.lhs
@@ -19,11 +19,11 @@ import Literal              ( literalType, Literal )
 import Maybes          ( catMaybes )
 import Name            ( getSrcLoc )
 import ErrUtils                ( ErrMsg, Message, addErrLocHdrLine, pprBagOfErrors, dontAddErrLoc )
-import Type            ( mkFunTys, splitFunTys, splitAlgTyConApp_maybe, splitTyConApp_maybe,
+import Type            ( mkFunTys, splitFunTys, splitTyConApp_maybe,
                          isUnLiftedType, isTyVarTy, splitForAllTys, Type
                        )
-import TyCon           ( TyCon )
-import Util            ( zipEqual )
+import TyCon           ( TyCon, isAlgTyCon, isNewTyCon, tyConDataCons )
+import Util            ( zipEqual, equalLength )
 import Outputable
 
 infixr 9 `thenL`, `thenL_`, `thenMaybeL`, `thenMaybeL_`
@@ -253,19 +253,21 @@ lintStgAlts alts scrut_ty
          check ty = checkTys first_ty ty (mkCaseAltMsg alts)
 
 lintAlgAlt scrut_ty (con, args, _, rhs)
-  = (case splitAlgTyConApp_maybe scrut_ty of
-      Nothing ->
-        addErrL (mkAlgAltMsg1 scrut_ty)
-      Just (tycon, tys_applied, cons) ->
+  = (case splitTyConApp_maybe scrut_ty of
+      Just (tycon, tys_applied) | isAlgTyCon tycon && 
+                                 not (isNewTyCon tycon) ->
         let
+          cons    = tyConDataCons tycon
           arg_tys = dataConArgTys con tys_applied
                -- This almost certainly does not work for existential constructors
         in
         checkL (con `elem` cons) (mkAlgAltMsg2 scrut_ty con) `thenL_`
-        checkL (length arg_tys == length args) (mkAlgAltMsg3 con args)
+        checkL (equalLength arg_tys args) (mkAlgAltMsg3 con args)
                                                                 `thenL_`
         mapL check (zipEqual "lintAlgAlt:stg" arg_tys args)     `thenL_`
         returnL ()
+      other ->
+        addErrL (mkAlgAltMsg1 scrut_ty)
     )                                                           `thenL_`
     addInScopeVars args        (
         lintStgExpr rhs
@@ -425,7 +427,7 @@ checkFunApp :: Type                     -- The function type
 checkFunApp fun_ty arg_tys msg loc scope errs
   = cfa res_ty expected_arg_tys arg_tys
   where
-    (_, de_forall_ty)   = splitForAllTys fun_ty
+    (_, de_forall_ty)         = splitForAllTys fun_ty
     (expected_arg_tys, res_ty) = splitFunTys de_forall_ty
 
     cfa res_ty expected []     -- Args have run out; that's fine