// Here we explicitly #[cfg]-out this whole crate when testing. If we don't do
// this, both the generated test artifact and the linked libtest (which
// transitively includes libcore) will both define the same set of lang items,
-// and this will cause the E0152 "duplicate lang item found" error. See
+// and this will cause the E0152 "found duplicate lang item" error. See
// discussion in #50466 for details.
//
// This cfg won't affect doc tests.
#![feature(associated_type_bounds)]
#![feature(const_type_id)]
#![feature(const_caller_location)]
-#![feature(slice_patterns)]
+#![cfg_attr(bootstrap, feature(slice_patterns))]
#[prelude_import]
#[allow(unused)]