diff --git a/_tags b/_tags
index e89e7e22..5a3bb15a 100644
--- a/_tags
+++ b/_tags
@@ -160,4 +160,4 @@
 <tests/*.ml{,i}>: thread
 <threads/*.ml{,i}>: thread
 <sequence>: -traverse
-<{string,core}/**/*.ml>: warn_K, warn_Y, warn_X
+<{string,core}/**/*.ml>: warn_A, warn(-4)