diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
index ac6701e6119db7d5424a9d5a13c5d682b75596f2..837161109c6d2e98ec0e41cb90762383487820b3 100644
--- a/src/libstd/lib.rs
+++ b/src/libstd/lib.rs
@@ -310,6 +310,7 @@
 #![feature(untagged_unions)]
 #![feature(unwind_attributes)]
 #![feature(vec_into_raw_parts)]
+#![feature(wake_trait)]
 // NB: the above list is sorted to minimize merge conflicts.
 #![default_lib_allocator]