X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Frename%2FRnExpr.lhs;h=f71b17c5aea2ce8199b4d4606fae12fc1214f759;hp=3a288bba8b64aef98c607208f3a55a6ca8b2c5f2;hb=6cec61d14a324285dbb8ce73d4c7215f1f8d6766;hpb=163d12852002a67c5b661b4b3e7e3c5bb6faa5f3

diff --git a/compiler/rename/RnExpr.lhs b/compiler/rename/RnExpr.lhs
index 3a288bb..f71b17c 100644
--- 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