Add Into<NonNull<T>> impls for Arc<T>/Rc<T>

Author: dwijnand

src/liballoc/rc.rs

@@ -1179,6 +1179,14 @@ impl<T> From<Vec<T>> for Rc<[T]> {
     }
 }
 
+#[unstable(feature = "rc_into_nonnull", reason = "newly added", issue = "0")]
+impl<T: ?Sized> Into<NonNull<T>> for Rc<T> {
+    #[inline]
+    fn into(self) -> NonNull<T> {
+        unsafe { NonNull::new_unchecked(Rc::into_raw(self) as *mut _) }
+    }
+}
+
 /// `Weak` is a version of [`Rc`] that holds a non-owning reference to the
 /// managed value. The value is accessed by calling [`upgrade`] on the `Weak`
 /// pointer, which returns an [`Option`]`<`[`Rc`]`<T>>`.

src/liballoc/sync.rs

@@ -1574,6 +1574,14 @@ impl<T> From<Vec<T>> for Arc<[T]> {
     }
 }
 
+#[unstable(feature = "arc_into_nonnull", reason = "newly added", issue = "0")]
+impl<T: ?Sized> Into<NonNull<T>> for Arc<T> {
+    #[inline]
+    fn into(self) -> NonNull<T> {
+        unsafe { NonNull::new_unchecked(Arc::into_raw(self) as *mut _) }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use std::boxed::Box;

src/liballoc/tests/arc.rs

@@ -95,3 +95,8 @@ fn eq() {
     assert!(!(x != x));
     assert_eq!(*x.0.borrow(), 0);
 }
+
+#[test]
+fn to_nonnull() {
+    let _: std::ptr::NonNull<i32> = Arc::new(0).into();
+}

src/liballoc/tests/rc.rs

@@ -95,3 +95,8 @@ fn eq() {
     assert!(!(x != x));
     assert_eq!(*x.0.borrow(), 0);
 }
+
+#[test]
+fn to_nonnull() {
+    let _: std::ptr::NonNull<i32> = Rc::new(0).into();
+}