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[EXPERIMENT] libs: relax Deref::Target #148102

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[EXPERIMENT] libs: relax Deref::Target #148102

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18 changes: 9 additions & 9 deletions library/core/src/ops/deref.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -141,7 +141,7 @@ pub const trait Deref: PointeeSized {
#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_diagnostic_item = "deref_target"]
#[lang = "deref_target"]
type Target: ?Sized;
type Target: PointeeSized;

/// Dereferences the value.
#[must_use]
Expand All @@ -152,7 +152,7 @@ pub const trait Deref: PointeeSized {

#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_const_unstable(feature = "const_convert", issue = "143773")]
impl<T: ?Sized> const Deref for &T {
impl<T: PointeeSized> const Deref for &T {
type Target = T;

#[rustc_diagnostic_item = "noop_method_deref"]
Expand All @@ -162,11 +162,11 @@ impl<T: ?Sized> const Deref for &T {
}

#[stable(feature = "rust1", since = "1.0.0")]
impl<T: ?Sized> !DerefMut for &T {}
impl<T: PointeeSized> !DerefMut for &T {}

#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_const_unstable(feature = "const_convert", issue = "143773")]
impl<T: ?Sized> const Deref for &mut T {
impl<T: PointeeSized> const Deref for &mut T {
type Target = T;

fn deref(&self) -> &T {
Expand Down Expand Up @@ -276,7 +276,7 @@ pub const trait DerefMut: [const] Deref + PointeeSized {

#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_const_unstable(feature = "const_convert", issue = "143773")]
impl<T: ?Sized> const DerefMut for &mut T {
impl<T: PointeeSized> const DerefMut for &mut T {
fn deref_mut(&mut self) -> &mut T {
self
}
Expand All @@ -296,10 +296,10 @@ impl<T: ?Sized> const DerefMut for &mut T {
pub unsafe trait DerefPure: PointeeSized {}

#[unstable(feature = "deref_pure_trait", issue = "87121")]
unsafe impl<T: ?Sized> DerefPure for &T {}
unsafe impl<T: PointeeSized> DerefPure for &T {}

#[unstable(feature = "deref_pure_trait", issue = "87121")]
unsafe impl<T: ?Sized> DerefPure for &mut T {}
unsafe impl<T: PointeeSized> DerefPure for &mut T {}

/// Indicates that a struct can be used as a method receiver.
/// That is, a type can use this type as a type of `self`, like this:
Expand Down Expand Up @@ -371,11 +371,11 @@ pub trait Receiver: PointeeSized {
#[rustc_diagnostic_item = "receiver_target"]
#[lang = "receiver_target"]
#[unstable(feature = "arbitrary_self_types", issue = "44874")]
type Target: ?Sized;
type Target: PointeeSized;
}

#[unstable(feature = "arbitrary_self_types", issue = "44874")]
impl<P: ?Sized, T: ?Sized> Receiver for P
impl<P: PointeeSized, T: PointeeSized> Receiver for P
where
P: Deref<Target = T>,
{
Expand Down
24 changes: 12 additions & 12 deletions library/core/src/pin.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -926,7 +926,7 @@ use crate::ops::{CoerceUnsized, Deref, DerefMut, DerefPure, DispatchFromDyn, Leg
use crate::{
cell::{RefCell, UnsafeCell},
future::Future,
marker::PhantomPinned,
marker::{PhantomPinned, PointeeSized},
mem, ptr,
};
use crate::{cmp, fmt};
Expand Down Expand Up @@ -1516,7 +1516,7 @@ impl<Ptr: Deref> Pin<Ptr> {
}
}

impl<'a, T: ?Sized> Pin<&'a T> {
impl<'a, T: PointeeSized> Pin<&'a T> {
/// Constructs a new pin by mapping the interior value.
///
/// For example, if you wanted to get a `Pin` of a field of something,
Expand All @@ -1535,7 +1535,7 @@ impl<'a, T: ?Sized> Pin<&'a T> {
#[stable(feature = "pin", since = "1.33.0")]
pub unsafe fn map_unchecked<U, F>(self, func: F) -> Pin<&'a U>
where
U: ?Sized,
U: PointeeSized,
F: FnOnce(&T) -> &U,
{
let pointer = &*self.pointer;
Expand Down Expand Up @@ -1572,7 +1572,7 @@ impl<'a, T: ?Sized> Pin<&'a T> {
}
}

impl<'a, T: ?Sized> Pin<&'a mut T> {
impl<'a, T: PointeeSized> Pin<&'a mut T> {
/// Converts this `Pin<&mut T>` into a `Pin<&T>` with the same lifetime.
#[inline(always)]
#[must_use = "`self` will be dropped if the result is not used"]
Expand Down Expand Up @@ -1639,7 +1639,7 @@ impl<'a, T: ?Sized> Pin<&'a mut T> {
#[stable(feature = "pin", since = "1.33.0")]
pub unsafe fn map_unchecked_mut<U, F>(self, func: F) -> Pin<&'a mut U>
where
U: ?Sized,
U: PointeeSized,
F: FnOnce(&mut T) -> &mut U,
{
// SAFETY: the caller is responsible for not moving the
Expand All @@ -1652,7 +1652,7 @@ impl<'a, T: ?Sized> Pin<&'a mut T> {
}
}

impl<T: ?Sized> Pin<&'static T> {
impl<T: PointeeSized> Pin<&'static T> {
/// Gets a pinning reference from a `&'static` reference.
///
/// This is safe because `T` is borrowed immutably for the `'static` lifetime, which
Expand All @@ -1666,7 +1666,7 @@ impl<T: ?Sized> Pin<&'static T> {
}
}

impl<T: ?Sized> Pin<&'static mut T> {
impl<T: PointeeSized> Pin<&'static mut T> {
/// Gets a pinning mutable reference from a static mutable reference.
///
/// This is safe because `T` is borrowed for the `'static` lifetime, which
Expand Down Expand Up @@ -1719,7 +1719,7 @@ mod helper {
#[rustc_const_unstable(feature = "const_convert", issue = "143773")]
#[rustc_diagnostic_item = "PinDerefMutHelper"]
pub const trait PinDerefMutHelper {
type Target: ?Sized;
type Target: super::PointeeSized;
fn deref_mut(&mut self) -> &mut Self::Target;
}

Expand Down Expand Up @@ -1847,19 +1847,19 @@ where
pub unsafe trait PinCoerceUnsized {}

#[stable(feature = "pin", since = "1.33.0")]
unsafe impl<'a, T: ?Sized> PinCoerceUnsized for &'a T {}
unsafe impl<'a, T: PointeeSized> PinCoerceUnsized for &'a T {}

#[stable(feature = "pin", since = "1.33.0")]
unsafe impl<'a, T: ?Sized> PinCoerceUnsized for &'a mut T {}
unsafe impl<'a, T: PointeeSized> PinCoerceUnsized for &'a mut T {}

#[stable(feature = "pin", since = "1.33.0")]
unsafe impl<T: PinCoerceUnsized> PinCoerceUnsized for Pin<T> {}

#[stable(feature = "pin", since = "1.33.0")]
unsafe impl<T: ?Sized> PinCoerceUnsized for *const T {}
unsafe impl<T: PointeeSized> PinCoerceUnsized for *const T {}

#[stable(feature = "pin", since = "1.33.0")]
unsafe impl<T: ?Sized> PinCoerceUnsized for *mut T {}
unsafe impl<T: PointeeSized> PinCoerceUnsized for *mut T {}

/// Constructs a <code>[Pin]<[&mut] T></code>, by pinning a `value: T` locally.
///
Expand Down
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