?Sized bounds for rc::Weak::as_ptr and friends

library/alloc/src/rc.rs

@@ -1721,7 +1721,21 @@ impl<T> Weak<T> {
     pub fn new() -> Weak<T> {
         Weak { ptr: NonNull::new(usize::MAX as *mut RcBox<T>).expect("MAX is not 0") }
     }
+}
+
+pub(crate) fn is_dangling<T: ?Sized>(ptr: NonNull<T>) -> bool {
+    let address = ptr.as_ptr() as *mut () as usize;
+    address == usize::MAX
+}
+
+/// Helper type to allow accessing the reference counts without
+/// making any assertions about the data field.
+struct WeakInner<'a> {
+    weak: &'a Cell<usize>,
+    strong: &'a Cell<usize>,
+}
 
+impl<T: ?Sized> Weak<T> {
     /// Returns a raw pointer to the object `T` pointed to by this `Weak<T>`.
     ///
     /// The pointer is valid only if there are some strong references. The pointer may be dangling,
@@ -1854,21 +1868,7 @@ impl<T> Weak<T> {
         // SAFETY: we now have recovered the original Weak pointer, so can create the Weak.
         Weak { ptr: unsafe { NonNull::new_unchecked(ptr) } }
     }
-}
-
-pub(crate) fn is_dangling<T: ?Sized>(ptr: NonNull<T>) -> bool {
-    let address = ptr.as_ptr() as *mut () as usize;
-    address == usize::MAX
-}
-
-/// Helper type to allow accessing the reference counts without
-/// making any assertions about the data field.
-struct WeakInner<'a> {
-    weak: &'a Cell<usize>,
-    strong: &'a Cell<usize>,
-}
 
-impl<T: ?Sized> Weak<T> {
     /// Attempts to upgrade the `Weak` pointer to an [`Rc`], delaying
     /// dropping of the inner value if successful.
     ///