diff --git a/lib/Option/features.json b/lib/Option/features.json
index 4bef4b444b0d5..f9c87c00022b9 100644
--- a/lib/Option/features.json
+++ b/lib/Option/features.json
@@ -47,6 +47,9 @@
     },
     {
        "name": "experimental-package-interface-load"
+    },
+    {
+       "name": "Isystem"
     }
   ]
 }