diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
index 72d998de9c4..32023a5b75b 100644
--- a/src/libstd/lib.rs
+++ b/src/libstd/lib.rs
@@ -244,7 +244,6 @@
 #![feature(cfg_target_thread_local)]
 #![feature(char_error_internals)]
 #![feature(clamp)]
-#![feature(compiler_builtins_lib)]
 #![feature(concat_idents)]
 #![feature(const_cstr_unchecked)]
 #![feature(const_raw_ptr_deref)]