diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
index 3a96884d45d9..0fe720e70cf0 100644
--- a/src/librustdoc/lib.rs
+++ b/src/librustdoc/lib.rs
@@ -7,7 +7,6 @@
 #![feature(assert_matches)]
 #![feature(box_patterns)]
 #![feature(control_flow_enum)]
-#![feature(box_syntax)]
 #![feature(drain_filter)]
 #![cfg_attr(bootstrap, feature(let_chains))]
 #![feature(let_else)]