Deprecate core::nonzero in favor of ptr::NonNull and num::NonZero*

Author: SimonSapin

src/libcore/nonzero.rs

@@ -10,8 +10,11 @@
 
 //! Exposes the NonZero lang item which provides optimization hints.
 #![unstable(feature = "nonzero",
-            reason = "needs an RFC to flesh out the design",
+            reason = "deprecated",
             issue = "27730")]
+#![rustc_deprecated(reason = "use `std::ptr::NonNull` or `std::num::NonZero*` instead",
+                    since = "1.26.0")]
+#![allow(deprecated)]
 
 use ops::CoerceUnsized;
 

src/libcore/num/mod.rs

@@ -15,7 +15,7 @@
 use convert::{Infallible, TryFrom};
 use fmt;
 use intrinsics;
-use nonzero::NonZero;
+#[allow(deprecated)] use nonzero::NonZero;
 use ops;
 use str::FromStr;
 
@@ -46,9 +46,11 @@ macro_rules! nonzero_integers {
             /// assert_eq!(size_of::<Option<std::num::NonZeroU32>>(), size_of::<u32>());
             /// ```
             #[$stability]
+            #[allow(deprecated)]
             #[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
             pub struct $Ty(NonZero<$Int>);
 
+            #[allow(deprecated)]
             impl $Ty {
                 /// Create a non-zero without checking the value.
                 ///

src/libcore/ptr.rs

@@ -23,7 +23,7 @@ use fmt;
 use hash;
 use marker::{PhantomData, Unsize};
 use mem;
-use nonzero::NonZero;
+#[allow(deprecated)] use nonzero::NonZero;
 
 use cmp::Ordering::{self, Less, Equal, Greater};
 
@@ -2285,6 +2285,7 @@ impl<T: ?Sized> PartialOrd for *mut T {
 #[unstable(feature = "ptr_internals", issue = "0",
            reason = "use NonNull instead and consider PhantomData<T> \
                      (if you also use #[may_dangle]), Send, and/or Sync")]
+#[allow(deprecated)]
 pub struct Unique<T: ?Sized> {
     pointer: NonZero<*const T>,
     // NOTE: this marker has no consequences for variance, but is necessary
@@ -2332,6 +2333,7 @@ impl<T: Sized> Unique<T> {
 }
 
 #[unstable(feature = "ptr_internals", issue = "0")]
+#[allow(deprecated)]
 impl<T: ?Sized> Unique<T> {
     /// Creates a new `Unique`.
     ///
@@ -2392,13 +2394,15 @@ impl<T: ?Sized> fmt::Pointer for Unique<T> {
 }
 
 #[unstable(feature = "ptr_internals", issue = "0")]
+#[allow(deprecated)]
 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 = "ptr_internals", issue = "0")]
+#[allow(deprecated)]
 impl<'a, T: ?Sized> From<&'a T> for Unique<T> {
     fn from(reference: &'a T) -> Self {
         Unique { pointer: NonZero::from(reference), _marker: PhantomData }
@@ -2436,7 +2440,7 @@ pub type Shared<T> = NonNull<T>;
 /// provide a public API that follows the normal shared XOR mutable rules of Rust.
 #[stable(feature = "nonnull", since = "1.25.0")]
 pub struct NonNull<T: ?Sized> {
-    pointer: NonZero<*const T>,
+    #[allow(deprecated)] pointer: NonZero<*const T>,
 }
 
 /// `NonNull` pointers are not `Send` because the data they reference may be aliased.
@@ -2463,6 +2467,7 @@ impl<T: Sized> NonNull<T> {
     }
 }
 
+#[allow(deprecated)]
 impl<T: ?Sized> NonNull<T> {
     /// Creates a new `NonNull`.
     ///
@@ -2581,13 +2586,15 @@ impl<T: ?Sized> From<Unique<T>> for NonNull<T> {
 }
 
 #[stable(feature = "nonnull", since = "1.25.0")]
+#[allow(deprecated)]
 impl<'a, T: ?Sized> From<&'a mut T> for NonNull<T> {
     fn from(reference: &'a mut T) -> Self {
         NonNull { pointer: NonZero::from(reference) }
     }
 }
 
 #[stable(feature = "nonnull", since = "1.25.0")]
+#[allow(deprecated)]
 impl<'a, T: ?Sized> From<&'a T> for NonNull<T> {
     fn from(reference: &'a T) -> Self {
         NonNull { pointer: NonZero::from(reference) }