X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Frename%2FRnBinds.lhs;h=13d4b33fad550dd62c94da1938eb24b5479e60c1;hb=191292aaa7f56f32fc546478f43aa89ac67c95a3;hp=03dfa08851cc062391ee1f95df155ef2f5330166;hpb=2a26efb65343e31957b043f63c43caf24d5eeb30;p=ghc-hetmet.git

diff --git a/compiler/rename/RnBinds.lhs b/compiler/rename/RnBinds.lhs
index 03dfa08..13d4b33 100644
--- a/compiler/rename/RnBinds.lhs
+++ b/compiler/rename/RnBinds.lhs
@@ -357,7 +357,9 @@ rnLocalValBindsAndThen binds@(ValBindsIn _ sigs) thing_inside
 		-- 	let x = x in 3
 		-- should report 'x' unused
 	; let real_uses = findUses dus result_fvs
-	; warnUnusedLocalBinds bound_names real_uses
+	      -- Insert fake uses for variables introduced implicitly by wildcards (#4404)
+	      implicit_uses = hsValBindsImplicits binds'
+	; warnUnusedLocalBinds bound_names (real_uses `unionNameSets` implicit_uses)
 
 	; let
             -- The variables "used" in the val binds are: 
@@ -719,7 +721,7 @@ renameSig _ (SpecInstSig ty)
 -- {-# SPECIALISE #-} pragmas can refer to imported Ids
 -- so, in the top-level case (when mb_names is Nothing)
 -- we use lookupOccRn.  If there's both an imported and a local 'f'
--- then the SPECIALISE pragma is ambiguous, unlike alll other signatures
+-- then the SPECIALISE pragma is ambiguous, unlike all other signatures
 renameSig mb_names sig@(SpecSig v ty inl)
   = do	{ new_v <- case mb_names of
                      Just {} -> lookupSigOccRn mb_names sig v