merge up to ghc HEAD 16-Apr-2011

[ghc-hetmet.git] / compiler / rename / RnExpr.lhs

diff --git a/compiler/rename/RnExpr.lhs b/compiler/rename/RnExpr.lhs
index 3a288bb..f71b17c 100644 (file)
--- a/compiler/rename/RnExpr.lhs
+++ b/compiler/rename/RnExpr.lhs
@@ -899,13 +899,15 @@ 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