Add conversions from references to NonZero pointers, Unique, and Shared

2 files changed, 47 insertions, 0 deletions

diff --git a/src/libcore/nonzero.rs b/src/libcore/nonzero.rs
index 65ebb8c5ae3..3ff1068b937 100644
--- a/src/libcore/nonzero.rs
+++ b/src/libcore/nonzero.rs
@@ -90,3 +90,22 @@ impl<T: Zeroable> NonZero<T> {
 }
 
 impl<T: Zeroable+CoerceUnsized<U>, U: Zeroable> CoerceUnsized<NonZero<U>> for NonZero<T> {}
+
+impl<'a, T: ?Sized> From<&'a mut T> for NonZero<*mut T> {
+    fn from(reference: &'a mut T) -> Self {
+        NonZero(reference)
+    }
+}
+
+impl<'a, T: ?Sized> From<&'a mut T> for NonZero<*const T> {
+    fn from(reference: &'a mut T) -> Self {
+        let ptr: *mut T = reference;
+        NonZero(ptr)
+    }
+}
+
+impl<'a, T: ?Sized> From<&'a T> for NonZero<*const T> {
+    fn from(reference: &'a T) -> Self {
+        NonZero(reference)
+    }
+}
diff --git a/src/libcore/ptr.rs b/src/libcore/ptr.rs
index 29e2114f38a..9413a908cb1 100644
--- a/src/libcore/ptr.rs
+++ b/src/libcore/ptr.rs
@@ -1164,6 +1164,20 @@ impl<T: ?Sized> fmt::Pointer for Unique<T> {
     }
 }
 
+#[unstable(feature = "unique", issue = "27730")]
+impl<'a, T: ?Sized> From<&'a mut T> for Unique<T> {
+    fn from(reference: &'a mut T) -> Self {
+        Unique { pointer: NonZero::from(reference), _marker: PhantomData }
+    }
+}
+
+#[unstable(feature = "unique", issue = "27730")]
+impl<'a, T: ?Sized> From<&'a T> for Unique<T> {
+    fn from(reference: &'a T) -> Self {
+        Unique { pointer: NonZero::from(reference), _marker: PhantomData }
+    }
+}
+
 /// A wrapper around a raw `*mut T` that indicates that the possessor
 /// of this wrapper has shared ownership of the referent. Useful for
 /// building abstractions like `Rc<T>`, `Arc<T>`, or doubly-linked lists, which
@@ -1296,3 +1310,17 @@ impl<T: ?Sized> From<Unique<T>> for Shared<T> {
         Shared { pointer: unique.pointer, _marker: PhantomData }
     }
 }
+
+#[unstable(feature = "shared", issue = "27730")]
+impl<'a, T: ?Sized> From<&'a mut T> for Shared<T> {
+    fn from(reference: &'a mut T) -> Self {
+        Shared { pointer: NonZero::from(reference), _marker: PhantomData }
+    }
+}
+
+#[unstable(feature = "shared", issue = "27730")]
+impl<'a, T: ?Sized> From<&'a T> for Shared<T> {
+    fn from(reference: &'a T) -> Self {
+        Shared { pointer: NonZero::from(reference), _marker: PhantomData }
+    }
+}