Support for -fwarn-unused-do-bind and -fwarn-wrong-do-bind, as per #3263

[ghc-hetmet.git] / compiler / typecheck / TcPat.lhs

diff --git a/compiler/typecheck/TcPat.lhs b/compiler/typecheck/TcPat.lhs
index bef5ec7..376385a 100644 (file)
--- a/compiler/typecheck/TcPat.lhs
+++ b/compiler/typecheck/TcPat.lhs
@@ -181,7 +181,7 @@ tcPatBndr :: PatState -> Name -> BoxySigmaType -> TcM TcId
 tcPatBndr (PS { pat_ctxt = LetPat lookup_sig }) bndr_name pat_ty
   | Just mono_ty <- lookup_sig bndr_name
   = do { mono_name <- newLocalName bndr_name
-       ; boxyUnify mono_ty pat_ty
+       ; _ <- boxyUnify mono_ty pat_ty
        ; return (Id.mkLocalId mono_name mono_ty) }
 
   | otherwise
@@ -238,7 +238,7 @@ unBoxArgType ty pp_this
                return ty'
          else do       -- OpenTypeKind, so constrain it
        { ty2 <- newFlexiTyVarTy argTypeKind
-       ; unifyType ty' ty2
+       ; _ <- unifyType ty' ty2
        ; return ty' }}
   where
     msg = pp_this <+> ptext (sLit "cannot be bound to an unboxed tuple")
@@ -373,7 +373,7 @@ tc_pat pstate lpat@(LazyPat pat) pat_ty thing_inside
 
        -- Check that the pattern has a lifted type
        ; pat_tv <- newBoxyTyVar liftedTypeKind
-       ; boxyUnify pat_ty (mkTyVarTy pat_tv)
+       ; _ <- boxyUnify pat_ty (mkTyVarTy pat_tv)
 
        ; return (LazyPat pat', [], res) }