diff --git a/src/librustc/lint/builtin.rs b/src/librustc/lint/builtin.rs
index f8a592d22c19c..8c556a09e1ebe 100644
--- a/src/librustc/lint/builtin.rs
+++ b/src/librustc/lint/builtin.rs
@@ -327,7 +327,7 @@ declare_lint! {
 
 declare_lint! {
     pub UNUSED_LABELS,
-    Allow,
+    Warn,
     "detects labels that are never used"
 }