X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Frename%2FRnExpr.lhs;h=1b7eef0253534341c78f571393c7eea67c5fb76f;hb=1851bb3cb6b5e9f0d413da7afc9b58c768888ecf;hp=3a288bba8b64aef98c607208f3a55a6ca8b2c5f2;hpb=34c8d0312071f7d0f4d221a997d3408c653ef9e5;p=ghc-hetmet.git

diff --git a/compiler/rename/RnExpr.lhs b/compiler/rename/RnExpr.lhs
index 3a288bb..1b7eef0 100644
--- a/compiler/rename/RnExpr.lhs
+++ b/compiler/rename/RnExpr.lhs
@@ -291,15 +291,10 @@ rnExpr (ExprWithTySig expr pty)
 
 rnExpr (HsIf _ p b1 b2)
   = do { (p', fvP) <- rnLExpr p
-    ; (b1', fvB1) <- rnLExpr b1
-    ; (b2', fvB2) <- rnLExpr b2
-    ; rebind <- xoptM Opt_RebindableSyntax
-    ; if not rebind
-       then return (HsIf Nothing p' b1' b2', plusFVs [fvP, fvB1, fvB2])
-       else do { hetMetLevel <- getHetMetLevel
-               ; n <- lookupOccRn $ mkRdrUnqual $ setOccNameDepth (length hetMetLevel) (mkVarOccFS (fsLit "ifThenElse"))
-               ; c <- return $ HsVar n
-               ; return (HsIf (Just c) p' b1' b2', plusFVs [fvP, fvB1, fvB2]) }}
+       ; (b1', fvB1) <- rnLExpr b1
+       ; (b2', fvB2) <- rnLExpr b2
+       ; (mb_ite, fvITE) <- lookupIfThenElse
+       ; return (HsIf mb_ite p' b1' b2', plusFVs [fvITE, fvP, fvB1, fvB2]) }
 
 rnExpr (HsType a)
   = rnHsTypeFVs doc a	`thenM` \ (t, fvT) -> 
@@ -899,13 +894,15 @@ rnRecStmtsAndThen s cont
 
 	  --    ...bring them and their fixities into scope
 	; let bound_names = collectLStmtsBinders (map fst new_lhs_and_fv)
+	      -- Fake uses of variables introduced implicitly (warning suppression, see #4404)
+	      implicit_uses = lStmtsImplicits (map fst new_lhs_and_fv)
 	; bindLocalNamesFV bound_names $
           addLocalFixities fix_env bound_names $ do
 
 	  -- (C) do the right-hand-sides and thing-inside
 	{ segs <- rn_rec_stmts bound_names new_lhs_and_fv
 	; (res, fvs) <- cont segs 
-	; warnUnusedLocalBinds bound_names fvs
+	; warnUnusedLocalBinds bound_names (fvs `unionNameSets` implicit_uses)
 	; return (res, fvs) }}
 
 -- get all the fixity decls in any Let stmt