2 files changed, 0 insertions, 3 deletions
diff --git a/src/libcore/lib.rs b/src/libcore/lib.rs
index 2bb941b490e..bdfc1e66fd4 100644
--- a/src/libcore/lib.rs
+++ b/src/libcore/lib.rs
@@ -62,8 +62,6 @@
 #![warn(missing_docs)]
 #![warn(missing_debug_implementations)]
 #![deny(intra_doc_link_resolution_failure)] // rustdoc is run without -D warnings
-
-#![deny(rust_2018_idioms)]
 #![allow(explicit_outlives_requirements)]
 
 #![feature(allow_internal_unstable)]
diff --git a/src/libcore/tests/lib.rs b/src/libcore/tests/lib.rs
index 505f8b0a261..a3b108b2e9c 100644
--- a/src/libcore/tests/lib.rs
+++ b/src/libcore/tests/lib.rs
@@ -32,7 +32,6 @@
 #![feature(const_fn)]
 #![feature(iter_partition_in_place)]
 #![feature(iter_is_partitioned)]
-#![warn(rust_2018_idioms)]
 
 extern crate test;