diff options
| -rw-r--r-- | library/alloc/src/rc.rs | 28 |
1 files changed, 14 insertions, 14 deletions
diff --git a/library/alloc/src/rc.rs b/library/alloc/src/rc.rs index 27e6e110903..1d4ce8e2682 100644 --- a/library/alloc/src/rc.rs +++ b/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. /// |