X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Frename%2FRnBinds.lhs;fp=compiler%2Frename%2FRnBinds.lhs;h=ee30f46607beac164ac8ab4008f5c2fba1f8c524;hp=03dfa08851cc062391ee1f95df155ef2f5330166;hb=8419203b7eb5aa4bb13f8d1263632de4d10a4048;hpb=83f16ade9edf272c88c6b2ed8b8e951b905fe130

diff --git a/compiler/rename/RnBinds.lhs b/compiler/rename/RnBinds.lhs
index 03dfa08..ee30f46 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: