diff --git a/src/libcore/str/mod.rs b/src/libcore/str/mod.rs
index c765e06301d6792b660e2dd8d6df1aa0d7a67881..45421848cec5db602f26a4b3cd4ecdf02290cd1f 100644
--- a/src/libcore/str/mod.rs
+++ b/src/libcore/str/mod.rs
@@ -2214,7 +2214,7 @@ pub const fn as_ptr(&self) -> *const u8 {
     /// modified in a way that it remains valid UTF-8.
     ///
     /// [`u8`]: primitive.u8.html
-    #[unstable(feature = "str_as_mut_ptr", issue = "58215")]
+    #[stable(feature = "str_as_mut_ptr", since = "1.36.0")]
     #[inline]
     pub fn as_mut_ptr(&mut self) -> *mut u8 {
         self as *mut str as *mut u8