diff --git a/src/libcore/mem/mod.rs b/src/libcore/mem/mod.rs
index 4ffd0141242..1120d6d4bc5 100644
--- a/src/libcore/mem/mod.rs
+++ b/src/libcore/mem/mod.rs
@@ -111,7 +111,7 @@ pub use crate::intrinsics::transmute;
 #[inline]
 #[rustc_const_unstable(feature = "const_forget", issue = "69616")]
 #[stable(feature = "rust1", since = "1.0.0")]
-pub fn forget<T>(t: T) {
+pub const fn forget<T>(t: T) {
     ManuallyDrop::new(t);
 }