Make core::nonzero private

It is now an implementation detail of ptr::NonNull and num::NonZero*

Author: SimonSapin

src/libcore/lib.rs

@@ -171,7 +171,6 @@ pub mod prelude;
 
 pub mod intrinsics;
 pub mod mem;
-pub mod nonzero;
 pub mod ptr;
 pub mod hint;
 
@@ -221,6 +220,7 @@ pub mod heap {
 
 // note: does not need to be public
 mod iter_private;
+mod nonzero;
 mod tuple;
 mod unit;
 

src/libcore/nonzero.rs

@@ -9,103 +9,13 @@
 // except according to those terms.
 
 //! Exposes the NonZero lang item which provides optimization hints.
-#![unstable(feature = "nonzero", reason = "deprecated", issue = "49137")]
-#![rustc_deprecated(reason = "use `std::ptr::NonNull` or `std::num::NonZero*` instead",
-                    since = "1.26.0")]
-#![allow(deprecated)]
 
 use ops::CoerceUnsized;
 
-/// Unsafe trait to indicate what types are usable with the NonZero struct
-pub unsafe trait Zeroable {
-    /// Whether this value is zero
-    fn is_zero(&self) -> bool;
-}
-
-macro_rules! impl_zeroable_for_pointer_types {
-    ( $( $Ptr: ty )+ ) => {
-        $(
-            /// For fat pointers to be considered "zero", only the "data" part needs to be null.
-            unsafe impl<T: ?Sized> Zeroable for $Ptr {
-                #[inline]
-                fn is_zero(&self) -> bool {
-                    (*self).is_null()
-                }
-            }
-        )+
-    }
-}
-
-macro_rules! impl_zeroable_for_integer_types {
-    ( $( $Int: ty )+ ) => {
-        $(
-            unsafe impl Zeroable for $Int {
-                #[inline]
-                fn is_zero(&self) -> bool {
-                    *self == 0
-                }
-            }
-        )+
-    }
-}
-
-impl_zeroable_for_pointer_types! {
-    *const T
-    *mut T
-}
-
-impl_zeroable_for_integer_types! {
-    usize u8 u16 u32 u64 u128
-    isize i8 i16 i32 i64 i128
-}
-
 /// A wrapper type for raw pointers and integers that will never be
 /// NULL or 0 that might allow certain optimizations.
 #[lang = "non_zero"]
-#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Debug, Hash)]
-pub struct NonZero<T: Zeroable>(pub(crate) T);
-
-impl<T: Zeroable> NonZero<T> {
-    /// Creates an instance of NonZero with the provided value.
-    /// You must indeed ensure that the value is actually "non-zero".
-    #[inline]
-    pub const unsafe fn new_unchecked(inner: T) -> Self {
-        NonZero(inner)
-    }
-
-    /// Creates an instance of NonZero with the provided value.
-    #[inline]
-    pub fn new(inner: T) -> Option<Self> {
-        if inner.is_zero() {
-            None
-        } else {
-            Some(NonZero(inner))
-        }
-    }
-
-    /// Gets the inner value.
-    pub fn get(self) -> T {
-        self.0
-    }
-}
-
-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)
-    }
-}
+#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
+pub(crate) struct NonZero<T>(pub(crate) T);
 
-impl<'a, T: ?Sized> From<&'a T> for NonZero<*const T> {
-    fn from(reference: &'a T) -> Self {
-        NonZero(reference)
-    }
-}
+impl<T: CoerceUnsized<U>, U> CoerceUnsized<NonZero<U>> for NonZero<T> {}

src/libcore/num/mod.rs

@@ -16,7 +16,7 @@ use convert::TryFrom;
 use fmt;
 use intrinsics;
 use mem;
-#[allow(deprecated)] use nonzero::NonZero;
+use nonzero::NonZero;
 use ops;
 use str::FromStr;
 
@@ -49,11 +49,9 @@ macro_rules! nonzero_integers {
             /// ```
             #[$stability]
             #[$deprecation]
-            #[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;
-#[allow(deprecated)] use nonzero::NonZero;
+use nonzero::NonZero;
 
 use cmp::Ordering::{self, Less, Equal, Greater};
 
@@ -2742,7 +2742,6 @@ 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)]
 #[doc(hidden)]
 pub struct Unique<T: ?Sized> {
     pointer: NonZero<*const T>,
@@ -2790,7 +2789,6 @@ impl<T: Sized> Unique<T> {
 }
 
 #[unstable(feature = "ptr_internals", issue = "0")]
-#[allow(deprecated)]
 impl<T: ?Sized> Unique<T> {
     /// Creates a new `Unique`.
     ///
@@ -2855,15 +2853,13 @@ 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(reference as _), _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(reference as _), _marker: PhantomData }
@@ -2896,7 +2892,7 @@ impl<'a, T: ?Sized> From<NonNull<T>> for Unique<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> {
-    #[allow(deprecated)] pointer: NonZero<*const T>,
+    pointer: NonZero<*const T>,
 }
 
 /// `NonNull` pointers are not `Send` because the data they reference may be aliased.
@@ -2923,7 +2919,6 @@ impl<T: Sized> NonNull<T> {
     }
 }
 
-#[allow(deprecated)]
 impl<T: ?Sized> NonNull<T> {
     /// Creates a new `NonNull`.
     ///
@@ -3054,15 +3049,13 @@ 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(reference as _) }
     }
 }
 
 #[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(reference as _) }

src/test/run-pass/ctfe/tuple-struct-constructors.rs

@@ -10,11 +10,10 @@
 
 // https://github.com/rust-lang/rust/issues/41898
 
-#![feature(nonzero, const_fn)]
-extern crate core;
-use core::nonzero::NonZero;
+#![feature(nonzero)]
+use std::num::NonZeroU64;
 
 fn main() {
-    const FOO: NonZero<u64> = unsafe { NonZero::new_unchecked(2) };
+    const FOO: NonZeroU64 = unsafe { NonZeroU64::new_unchecked(2) };
     if let FOO = FOO {}
 }