Rollup merge of rust-lang#143308 - compiler-errors:no-pointer-like, r=oli-obk

Remove `PointerLike` trait

r? oli-obk

Author: matthiaskrgr

alloc/src/boxed.rs

@@ -191,7 +191,7 @@ use core::error::{self, Error};
 use core::fmt;
 use core::future::Future;
 use core::hash::{Hash, Hasher};
-use core::marker::{PointerLike, Tuple, Unsize};
+use core::marker::{Tuple, Unsize};
 use core::mem::{self, SizedTypeProperties};
 use core::ops::{
     AsyncFn, AsyncFnMut, AsyncFnOnce, CoerceUnsized, Coroutine, CoroutineState, Deref, DerefMut,
@@ -2132,6 +2132,3 @@ impl<E: Error> Error for Box<E> {
         Error::provide(&**self, request);
     }
 }
-
-#[unstable(feature = "pointer_like_trait", issue = "none")]
-impl<T> PointerLike for Box<T> {}

alloc/src/lib.rs

@@ -134,7 +134,6 @@
 #![feature(panic_internals)]
 #![feature(pattern)]
 #![feature(pin_coerce_unsized_trait)]
-#![feature(pointer_like_trait)]
 #![feature(ptr_alignment_type)]
 #![feature(ptr_internals)]
 #![feature(ptr_metadata)]

core/src/cell.rs

@@ -252,7 +252,7 @@
 
 use crate::cmp::Ordering;
 use crate::fmt::{self, Debug, Display};
-use crate::marker::{PhantomData, PointerLike, Unsize};
+use crate::marker::{PhantomData, Unsize};
 use crate::mem;
 use crate::ops::{CoerceUnsized, Deref, DerefMut, DerefPure, DispatchFromDyn};
 use crate::panic::const_panic;
@@ -669,9 +669,6 @@ impl<T: CoerceUnsized<U>, U> CoerceUnsized<Cell<U>> for Cell<T> {}
 #[unstable(feature = "dispatch_from_dyn", issue = "none")]
 impl<T: DispatchFromDyn<U>, U> DispatchFromDyn<Cell<U>> for Cell<T> {}
 
-#[unstable(feature = "pointer_like_trait", issue = "none")]
-impl<T: PointerLike> PointerLike for Cell<T> {}
-
 impl<T> Cell<[T]> {
     /// Returns a `&[Cell<T>]` from a `&Cell<[T]>`
     ///
@@ -2361,9 +2358,6 @@ impl<T: CoerceUnsized<U>, U> CoerceUnsized<UnsafeCell<U>> for UnsafeCell<T> {}
 #[unstable(feature = "dispatch_from_dyn", issue = "none")]
 impl<T: DispatchFromDyn<U>, U> DispatchFromDyn<UnsafeCell<U>> for UnsafeCell<T> {}
 
-#[unstable(feature = "pointer_like_trait", issue = "none")]
-impl<T: PointerLike> PointerLike for UnsafeCell<T> {}
-
 /// [`UnsafeCell`], but [`Sync`].
 ///
 /// This is just an `UnsafeCell`, except it implements `Sync`
@@ -2470,9 +2464,6 @@ impl<T: CoerceUnsized<U>, U> CoerceUnsized<SyncUnsafeCell<U>> for SyncUnsafeCell
 //#[unstable(feature = "sync_unsafe_cell", issue = "95439")]
 impl<T: DispatchFromDyn<U>, U> DispatchFromDyn<SyncUnsafeCell<U>> for SyncUnsafeCell<T> {}
 
-#[unstable(feature = "pointer_like_trait", issue = "none")]
-impl<T: PointerLike> PointerLike for SyncUnsafeCell<T> {}
-
 #[allow(unused)]
 fn assert_coerce_unsized(
     a: UnsafeCell<&i32>,

core/src/marker.rs

@@ -1066,37 +1066,6 @@ pub trait Destruct {}
 #[rustc_do_not_implement_via_object]
 pub trait Tuple {}
 
-/// A marker for pointer-like types.
-///
-/// This trait can only be implemented for types that are certain to have
-/// the same size and alignment as a [`usize`] or [`*const ()`](pointer).
-/// To ensure this, there are special requirements on implementations
-/// of `PointerLike` (other than the already-provided implementations
-/// for built-in types):
-///
-/// * The type must have `#[repr(transparent)]`.
-/// * The type’s sole non-zero-sized field must itself implement `PointerLike`.
-#[unstable(feature = "pointer_like_trait", issue = "none")]
-#[lang = "pointer_like"]
-#[diagnostic::on_unimplemented(
-    message = "`{Self}` needs to have the same ABI as a pointer",
-    label = "`{Self}` needs to be a pointer-like type"
-)]
-#[rustc_do_not_implement_via_object]
-pub trait PointerLike {}
-
-marker_impls! {
-    #[unstable(feature = "pointer_like_trait", issue = "none")]
-    PointerLike for
-        isize,
-        usize,
-        {T} &T,
-        {T} &mut T,
-        {T} *const T,
-        {T} *mut T,
-        {T: PointerLike} crate::pin::Pin<T>,
-}
-
 /// A marker for types which can be used as types of `const` generic parameters.
 ///
 /// These types must have a proper equivalence relation (`Eq`) and it must be automatically

core/src/pin/unsafe_pinned.rs

@@ -1,5 +1,5 @@
 use crate::cell::UnsafeCell;
-use crate::marker::{PointerLike, Unpin};
+use crate::marker::Unpin;
 use crate::ops::{CoerceUnsized, DispatchFromDyn};
 use crate::pin::Pin;
 use crate::{fmt, ptr};
@@ -178,8 +178,4 @@ impl<T: CoerceUnsized<U>, U> CoerceUnsized<UnsafePinned<U>> for UnsafePinned<T>
 // #[unstable(feature = "unsafe_pinned", issue = "125735")]
 impl<T: DispatchFromDyn<U>, U> DispatchFromDyn<UnsafePinned<U>> for UnsafePinned<T> {}
 
-#[unstable(feature = "pointer_like_trait", issue = "none")]
-// #[unstable(feature = "unsafe_pinned", issue = "125735")]
-impl<T: PointerLike> PointerLike for UnsafePinned<T> {}
-
 // FIXME(unsafe_pinned): impl PinCoerceUnsized for UnsafePinned<T>?

core/src/ptr/non_null.rs

@@ -1628,9 +1628,6 @@ impl<T: PointeeSized, U: PointeeSized> DispatchFromDyn<NonNull<U>> for NonNull<T
 #[stable(feature = "pin", since = "1.33.0")]
 unsafe impl<T: PointeeSized> PinCoerceUnsized for NonNull<T> {}
 
-#[unstable(feature = "pointer_like_trait", issue = "none")]
-impl<T> core::marker::PointerLike for NonNull<T> {}
-
 #[stable(feature = "nonnull", since = "1.25.0")]
 impl<T: PointeeSized> fmt::Debug for NonNull<T> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {