mv std libs to library/

1 files changed, 0 insertions, 932 deletions

diff --git a/src/libcore/ptr/const_ptr.rs b/src/libcore/ptr/const_ptr.rs
deleted file mode 100644
index a2acc239bd3..00000000000
--- a/src/libcore/ptr/const_ptr.rs
+++ /dev/null
@@ -1,932 +0,0 @@
-use super::*;
-use crate::cmp::Ordering::{self, Equal, Greater, Less};
-use crate::intrinsics;
-use crate::mem;
-use crate::slice::SliceIndex;
-
-#[lang = "const_ptr"]
-impl<T: ?Sized> *const T {
-    /// Returns `true` if the pointer is null.
-    ///
-    /// Note that unsized types have many possible null pointers, as only the
-    /// raw data pointer is considered, not their length, vtable, etc.
-    /// Therefore, two pointers that are null may still not compare equal to
-    /// each other.
-    ///
-    /// # Examples
-    ///
-    /// Basic usage:
-    ///
-    /// ```
-    /// let s: &str = "Follow the rabbit";
-    /// let ptr: *const u8 = s.as_ptr();
-    /// assert!(!ptr.is_null());
-    /// ```
-    #[stable(feature = "rust1", since = "1.0.0")]
-    #[inline]
-    pub fn is_null(self) -> bool {
-        // Compare via a cast to a thin pointer, so fat pointers are only
-        // considering their "data" part for null-ness.
-        (self as *const u8) == null()
-    }
-
-    /// Casts to a pointer of another type.
-    #[stable(feature = "ptr_cast", since = "1.38.0")]
-    #[rustc_const_stable(feature = "const_ptr_cast", since = "1.38.0")]
-    #[inline]
-    pub const fn cast<U>(self) -> *const U {
-        self as _
-    }
-
-    /// Returns `None` if the pointer is null, or else returns a reference to
-    /// the value wrapped in `Some`.
-    ///
-    /// # Safety
-    ///
-    /// While this method and its mutable counterpart are useful for
-    /// null-safety, it is important to note that this is still an unsafe
-    /// operation because the returned value could be pointing to invalid
-    /// memory.
-    ///
-    /// When calling this method, you have to ensure that *either* the pointer is NULL *or*
-    /// all of the following is true:
-    /// - it is properly aligned
-    /// - it must point to an initialized instance of T; in particular, the pointer must be
-    ///   "dereferenceable" in the sense defined [here].
-    ///
-    /// This applies even if the result of this method is unused!
-    /// (The part about being initialized is not yet fully decided, but until
-    /// it is, the only safe approach is to ensure that they are indeed initialized.)
-    ///
-    /// Additionally, the lifetime `'a` returned is arbitrarily chosen and does
-    /// not necessarily reflect the actual lifetime of the data. *You* must enforce
-    /// Rust's aliasing rules. In particular, for the duration of this lifetime,
-    /// the memory the pointer points to must not get mutated (except inside `UnsafeCell`).
-    ///
-    /// [here]: crate::ptr#safety
-    ///
-    /// # Examples
-    ///
-    /// Basic usage:
-    ///
-    /// ```
-    /// let ptr: *const u8 = &10u8 as *const u8;
-    ///
-    /// unsafe {
-    ///     if let Some(val_back) = ptr.as_ref() {
-    ///         println!("We got back the value: {}!", val_back);
-    ///     }
-    /// }
-    /// ```
-    ///
-    /// # Null-unchecked version
-    ///
-    /// If you are sure the pointer can never be null and are looking for some kind of
-    /// `as_ref_unchecked` that returns the `&T` instead of `Option<&T>`, know that you can
-    /// dereference the pointer directly.
-    ///
-    /// ```
-    /// let ptr: *const u8 = &10u8 as *const u8;
-    ///
-    /// unsafe {
-    ///     let val_back = &*ptr;
-    ///     println!("We got back the value: {}!", val_back);
-    /// }
-    /// ```
-    #[stable(feature = "ptr_as_ref", since = "1.9.0")]
-    #[inline]
-    pub unsafe fn as_ref<'a>(self) -> Option<&'a T> {
-        // SAFETY: the caller must guarantee that `self` is valid
-        // for a reference if it isn't null.
-        if self.is_null() { None } else { unsafe { Some(&*self) } }
-    }
-
-    /// Calculates the offset from a pointer.
-    ///
-    /// `count` is in units of T; e.g., a `count` of 3 represents a pointer
-    /// offset of `3 * size_of::<T>()` bytes.
-    ///
-    /// # Safety
-    ///
-    /// If any of the following conditions are violated, the result is Undefined
-    /// Behavior:
-    ///
-    /// * Both the starting and resulting pointer must be either in bounds or one
-    ///   byte past the end of the same allocated object. Note that in Rust,
-    ///   every (stack-allocated) variable is considered a separate allocated object.
-    ///
-    /// * The computed offset, **in bytes**, cannot overflow an `isize`.
-    ///
-    /// * The offset being in bounds cannot rely on "wrapping around" the address
-    ///   space. That is, the infinite-precision sum, **in bytes** must fit in a usize.
-    ///
-    /// The compiler and standard library generally tries to ensure allocations
-    /// never reach a size where an offset is a concern. For instance, `Vec`
-    /// and `Box` ensure they never allocate more than `isize::MAX` bytes, so
-    /// `vec.as_ptr().add(vec.len())` is always safe.
-    ///
-    /// Most platforms fundamentally can't even construct such an allocation.
-    /// For instance, no known 64-bit platform can ever serve a request
-    /// for 2<sup>63</sup> bytes due to page-table limitations or splitting the address space.
-    /// However, some 32-bit and 16-bit platforms may successfully serve a request for
-    /// more than `isize::MAX` bytes with things like Physical Address
-    /// Extension. As such, memory acquired directly from allocators or memory
-    /// mapped files *may* be too large to handle with this function.
-    ///
-    /// Consider using [`wrapping_offset`] instead if these constraints are
-    /// difficult to satisfy. The only advantage of this method is that it
-    /// enables more aggressive compiler optimizations.
-    ///
-    /// [`wrapping_offset`]: #method.wrapping_offset
-    ///
-    /// # Examples
-    ///
-    /// Basic usage:
-    ///
-    /// ```
-    /// let s: &str = "123";
-    /// let ptr: *const u8 = s.as_ptr();
-    ///
-    /// unsafe {
-    ///     println!("{}", *ptr.offset(1) as char);
-    ///     println!("{}", *ptr.offset(2) as char);
-    /// }
-    /// ```
-    #[stable(feature = "rust1", since = "1.0.0")]
-    #[must_use = "returns a new pointer rather than modifying its argument"]
-    #[rustc_const_unstable(feature = "const_ptr_offset", issue = "71499")]
-    #[inline]
-    pub const unsafe fn offset(self, count: isize) -> *const T
-    where
-        T: Sized,
-    {
-        // SAFETY: the caller must uphold the safety contract for `offset`.
-        unsafe { intrinsics::offset(self, count) }
-    }
-
-    /// Calculates the offset from a pointer using wrapping arithmetic.
-    ///
-    /// `count` is in units of T; e.g., a `count` of 3 represents a pointer
-    /// offset of `3 * size_of::<T>()` bytes.
-    ///
-    /// # Safety
-    ///
-    /// The resulting pointer does not need to be in bounds, but it is
-    /// potentially hazardous to dereference (which requires `unsafe`).
-    ///
-    /// In particular, the resulting pointer remains attached to the same allocated
-    /// object that `self` points to. It may *not* be used to access a
-    /// different allocated object. Note that in Rust,
-    /// every (stack-allocated) variable is considered a separate allocated object.
-    ///
-    /// In other words, `x.wrapping_offset(y.wrapping_offset_from(x))` is
-    /// *not* the same as `y`, and dereferencing it is undefined behavior
-    /// unless `x` and `y` point into the same allocated object.
-    ///
-    /// Compared to [`offset`], this method basically delays the requirement of staying
-    /// within the same allocated object: [`offset`] is immediate Undefined Behavior when
-    /// crossing object boundaries; `wrapping_offset` produces a pointer but still leads
-    /// to Undefined Behavior if that pointer is dereferenced. [`offset`] can be optimized
-    /// better and is thus preferable in performance-sensitive code.
-    ///
-    /// If you need to cross object boundaries, cast the pointer to an integer and
-    /// do the arithmetic there.
-    ///
-    /// [`offset`]: #method.offset
-    ///
-    /// # Examples
-    ///
-    /// Basic usage:
-    ///
-    /// ```
-    /// // Iterate using a raw pointer in increments of two elements
-    /// let data = [1u8, 2, 3, 4, 5];
-    /// let mut ptr: *const u8 = data.as_ptr();
-    /// let step = 2;
-    /// let end_rounded_up = ptr.wrapping_offset(6);
-    ///
-    /// // This loop prints "1, 3, 5, "
-    /// while ptr != end_rounded_up {
-    ///     unsafe {
-    ///         print!("{}, ", *ptr);
-    ///     }
-    ///     ptr = ptr.wrapping_offset(step);
-    /// }
-    /// ```
-    #[stable(feature = "ptr_wrapping_offset", since = "1.16.0")]
-    #[must_use = "returns a new pointer rather than modifying its argument"]
-    #[rustc_const_unstable(feature = "const_ptr_offset", issue = "71499")]
-    #[inline]
-    pub const fn wrapping_offset(self, count: isize) -> *const T
-    where
-        T: Sized,
-    {
-        // SAFETY: the `arith_offset` intrinsic has no prerequisites to be called.
-        unsafe { intrinsics::arith_offset(self, count) }
-    }
-
-    /// Calculates the distance between two pointers. The returned value is in
-    /// units of T: the distance in bytes is divided by `mem::size_of::<T>()`.
-    ///
-    /// This function is the inverse of [`offset`].
-    ///
-    /// [`offset`]: #method.offset
-    /// [`wrapping_offset_from`]: #method.wrapping_offset_from
-    ///
-    /// # Safety
-    ///
-    /// If any of the following conditions are violated, the result is Undefined
-    /// Behavior:
-    ///
-    /// * Both the starting and other pointer must be either in bounds or one
-    ///   byte past the end of the same allocated object. Note that in Rust,
-    ///   every (stack-allocated) variable is considered a separate allocated object.
-    ///
-    /// * The distance between the pointers, **in bytes**, cannot overflow an `isize`.
-    ///
-    /// * The distance between the pointers, in bytes, must be an exact multiple
-    ///   of the size of `T`.
-    ///
-    /// * The distance being in bounds cannot rely on "wrapping around" the address space.
-    ///
-    /// The compiler and standard library generally try to ensure allocations
-    /// never reach a size where an offset is a concern. For instance, `Vec`
-    /// and `Box` ensure they never allocate more than `isize::MAX` bytes, so
-    /// `ptr_into_vec.offset_from(vec.as_ptr())` is always safe.
-    ///
-    /// Most platforms fundamentally can't even construct such an allocation.
-    /// For instance, no known 64-bit platform can ever serve a request
-    /// for 2<sup>63</sup> bytes due to page-table limitations or splitting the address space.
-    /// However, some 32-bit and 16-bit platforms may successfully serve a request for
-    /// more than `isize::MAX` bytes with things like Physical Address
-    /// Extension. As such, memory acquired directly from allocators or memory
-    /// mapped files *may* be too large to handle with this function.
-    ///
-    /// Consider using [`wrapping_offset_from`] instead if these constraints are
-    /// difficult to satisfy. The only advantage of this method is that it
-    /// enables more aggressive compiler optimizations.
-    ///
-    /// # Panics
-    ///
-    /// This function panics if `T` is a Zero-Sized Type ("ZST").
-    ///
-    /// # Examples
-    ///
-    /// Basic usage:
-    ///
-    /// ```
-    /// #![feature(ptr_offset_from)]
-    ///
-    /// let a = [0; 5];
-    /// let ptr1: *const i32 = &a[1];
-    /// let ptr2: *const i32 = &a[3];
-    /// unsafe {
-    ///     assert_eq!(ptr2.offset_from(ptr1), 2);
-    ///     assert_eq!(ptr1.offset_from(ptr2), -2);
-    ///     assert_eq!(ptr1.offset(2), ptr2);
-    ///     assert_eq!(ptr2.offset(-2), ptr1);
-    /// }
-    /// ```
-    #[unstable(feature = "ptr_offset_from", issue = "41079")]
-    #[rustc_const_unstable(feature = "const_ptr_offset_from", issue = "41079")]
-    #[inline]
-    pub const unsafe fn offset_from(self, origin: *const T) -> isize
-    where
-        T: Sized,
-    {
-        let pointee_size = mem::size_of::<T>();
-        assert!(0 < pointee_size && pointee_size <= isize::MAX as usize);
-        // SAFETY: the caller must uphold the safety contract for `ptr_offset_from`.
-        unsafe { intrinsics::ptr_offset_from(self, origin) }
-    }
-
-    /// Returns whether two pointers are guaranteed to be equal.
-    ///
-    /// At runtime this function behaves like `self == other`.
-    /// However, in some contexts (e.g., compile-time evaluation),
-    /// it is not always possible to determine equality of two pointers, so this function may
-    /// spuriously return `false` for pointers that later actually turn out to be equal.
-    /// But when it returns `true`, the pointers are guaranteed to be equal.
-    ///
-    /// This function is the mirror of [`guaranteed_ne`], but not its inverse. There are pointer
-    /// comparisons for which both functions return `false`.
-    ///
-    /// [`guaranteed_ne`]: #method.guaranteed_ne
-    ///
-    /// The return value may change depending on the compiler version and unsafe code may not
-    /// rely on the result of this function for soundness. It is suggested to only use this function
-    /// for performance optimizations where spurious `false` return values by this function do not
-    /// affect the outcome, but just the performance.
-    /// The consequences of using this method to make runtime and compile-time code behave
-    /// differently have not been explored. This method should not be used to introduce such
-    /// differences, and it should also not be stabilized before we have a better understanding
-    /// of this issue.
-    #[unstable(feature = "const_raw_ptr_comparison", issue = "53020")]
-    #[rustc_const_unstable(feature = "const_raw_ptr_comparison", issue = "53020")]
-    #[inline]
-    pub const fn guaranteed_eq(self, other: *const T) -> bool
-    where
-        T: Sized,
-    {
-        intrinsics::ptr_guaranteed_eq(self, other)
-    }
-
-    /// Returns whether two pointers are guaranteed to be unequal.
-    ///
-    /// At runtime this function behaves like `self != other`.
-    /// However, in some contexts (e.g., compile-time evaluation),
-    /// it is not always possible to determine the inequality of two pointers, so this function may
-    /// spuriously return `false` for pointers that later actually turn out to be unequal.
-    /// But when it returns `true`, the pointers are guaranteed to be unequal.
-    ///
-    /// This function is the mirror of [`guaranteed_eq`], but not its inverse. There are pointer
-    /// comparisons for which both functions return `false`.
-    ///
-    /// [`guaranteed_eq`]: #method.guaranteed_eq
-    ///
-    /// The return value may change depending on the compiler version and unsafe code may not
-    /// rely on the result of this function for soundness. It is suggested to only use this function
-    /// for performance optimizations where spurious `false` return values by this function do not
-    /// affect the outcome, but just the performance.
-    /// The consequences of using this method to make runtime and compile-time code behave
-    /// differently have not been explored. This method should not be used to introduce such
-    /// differences, and it should also not be stabilized before we have a better understanding
-    /// of this issue.
-    #[unstable(feature = "const_raw_ptr_comparison", issue = "53020")]
-    #[rustc_const_unstable(feature = "const_raw_ptr_comparison", issue = "53020")]
-    #[inline]
-    pub const fn guaranteed_ne(self, other: *const T) -> bool
-    where
-        T: Sized,
-    {
-        intrinsics::ptr_guaranteed_ne(self, other)
-    }
-
-    /// Calculates the distance between two pointers. The returned value is in
-    /// units of T: the distance in bytes is divided by `mem::size_of::<T>()`.
-    ///
-    /// If the address different between the two pointers is not a multiple of
-    /// `mem::size_of::<T>()` then the result of the division is rounded towards
-    /// zero.
-    ///
-    /// Though this method is safe for any two pointers, note that its result
-    /// will be mostly useless if the two pointers aren't into the same allocated
-    /// object, for example if they point to two different local variables.
-    ///
-    /// # Panics
-    ///
-    /// This function panics if `T` is a zero-sized type.
-    ///
-    /// # Examples
-    ///
-    /// Basic usage:
-    ///
-    /// ```
-    /// #![feature(ptr_wrapping_offset_from)]
-    ///
-    /// let a = [0; 5];
-    /// let ptr1: *const i32 = &a[1];
-    /// let ptr2: *const i32 = &a[3];
-    /// assert_eq!(ptr2.wrapping_offset_from(ptr1), 2);
-    /// assert_eq!(ptr1.wrapping_offset_from(ptr2), -2);
-    /// assert_eq!(ptr1.wrapping_offset(2), ptr2);
-    /// assert_eq!(ptr2.wrapping_offset(-2), ptr1);
-    ///
-    /// let ptr1: *const i32 = 3 as _;
-    /// let ptr2: *const i32 = 13 as _;
-    /// assert_eq!(ptr2.wrapping_offset_from(ptr1), 2);
-    /// ```
-    #[unstable(feature = "ptr_wrapping_offset_from", issue = "41079")]
-    #[rustc_deprecated(
-        since = "1.46.0",
-        reason = "Pointer distances across allocation \
-        boundaries are not typically meaningful. \
-        Use integer subtraction if you really need this."
-    )]
-    #[inline]
-    pub fn wrapping_offset_from(self, origin: *const T) -> isize
-    where
-        T: Sized,
-    {
-        let pointee_size = mem::size_of::<T>();
-        assert!(0 < pointee_size && pointee_size <= isize::MAX as usize);
-
-        let d = isize::wrapping_sub(self as _, origin as _);
-        d.wrapping_div(pointee_size as _)
-    }
-
-    /// Calculates the offset from a pointer (convenience for `.offset(count as isize)`).
-    ///
-    /// `count` is in units of T; e.g., a `count` of 3 represents a pointer
-    /// offset of `3 * size_of::<T>()` bytes.
-    ///
-    /// # Safety
-    ///
-    /// If any of the following conditions are violated, the result is Undefined
-    /// Behavior:
-    ///
-    /// * Both the starting and resulting pointer must be either in bounds or one
-    ///   byte past the end of the same allocated object. Note that in Rust,
-    ///   every (stack-allocated) variable is considered a separate allocated object.
-    ///
-    /// * The computed offset, **in bytes**, cannot overflow an `isize`.
-    ///
-    /// * The offset being in bounds cannot rely on "wrapping around" the address
-    ///   space. That is, the infinite-precision sum must fit in a `usize`.
-    ///
-    /// The compiler and standard library generally tries to ensure allocations
-    /// never reach a size where an offset is a concern. For instance, `Vec`
-    /// and `Box` ensure they never allocate more than `isize::MAX` bytes, so
-    /// `vec.as_ptr().add(vec.len())` is always safe.
-    ///
-    /// Most platforms fundamentally can't even construct such an allocation.
-    /// For instance, no known 64-bit platform can ever serve a request
-    /// for 2<sup>63</sup> bytes due to page-table limitations or splitting the address space.
-    /// However, some 32-bit and 16-bit platforms may successfully serve a request for
-    /// more than `isize::MAX` bytes with things like Physical Address
-    /// Extension. As such, memory acquired directly from allocators or memory
-    /// mapped files *may* be too large to handle with this function.
-    ///
-    /// Consider using [`wrapping_add`] instead if these constraints are
-    /// difficult to satisfy. The only advantage of this method is that it
-    /// enables more aggressive compiler optimizations.
-    ///
-    /// [`wrapping_add`]: #method.wrapping_add
-    ///
-    /// # Examples
-    ///
-    /// Basic usage:
-    ///
-    /// ```
-    /// let s: &str = "123";
-    /// let ptr: *const u8 = s.as_ptr();
-    ///
-    /// unsafe {
-    ///     println!("{}", *ptr.add(1) as char);
-    ///     println!("{}", *ptr.add(2) as char);
-    /// }
-    /// ```
-    #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[must_use = "returns a new pointer rather than modifying its argument"]
-    #[rustc_const_unstable(feature = "const_ptr_offset", issue = "71499")]
-    #[inline]
-    pub const unsafe fn add(self, count: usize) -> Self
-    where
-        T: Sized,
-    {
-        // SAFETY: the caller must uphold the safety contract for `offset`.
-        unsafe { self.offset(count as isize) }
-    }
-
-    /// Calculates the offset from a pointer (convenience for
-    /// `.offset((count as isize).wrapping_neg())`).
-    ///
-    /// `count` is in units of T; e.g., a `count` of 3 represents a pointer
-    /// offset of `3 * size_of::<T>()` bytes.
-    ///
-    /// # Safety
-    ///
-    /// If any of the following conditions are violated, the result is Undefined
-    /// Behavior:
-    ///
-    /// * Both the starting and resulting pointer must be either in bounds or one
-    ///   byte past the end of the same allocated object. Note that in Rust,
-    ///   every (stack-allocated) variable is considered a separate allocated object.
-    ///
-    /// * The computed offset cannot exceed `isize::MAX` **bytes**.
-    ///
-    /// * The offset being in bounds cannot rely on "wrapping around" the address
-    ///   space. That is, the infinite-precision sum must fit in a usize.
-    ///
-    /// The compiler and standard library generally tries to ensure allocations
-    /// never reach a size where an offset is a concern. For instance, `Vec`
-    /// and `Box` ensure they never allocate more than `isize::MAX` bytes, so
-    /// `vec.as_ptr().add(vec.len()).sub(vec.len())` is always safe.
-    ///
-    /// Most platforms fundamentally can't even construct such an allocation.
-    /// For instance, no known 64-bit platform can ever serve a request
-    /// for 2<sup>63</sup> bytes due to page-table limitations or splitting the address space.
-    /// However, some 32-bit and 16-bit platforms may successfully serve a request for
-    /// more than `isize::MAX` bytes with things like Physical Address
-    /// Extension. As such, memory acquired directly from allocators or memory
-    /// mapped files *may* be too large to handle with this function.
-    ///
-    /// Consider using [`wrapping_sub`] instead if these constraints are
-    /// difficult to satisfy. The only advantage of this method is that it
-    /// enables more aggressive compiler optimizations.
-    ///
-    /// [`wrapping_sub`]: #method.wrapping_sub
-    ///
-    /// # Examples
-    ///
-    /// Basic usage:
-    ///
-    /// ```
-    /// let s: &str = "123";
-    ///
-    /// unsafe {
-    ///     let end: *const u8 = s.as_ptr().add(3);
-    ///     println!("{}", *end.sub(1) as char);
-    ///     println!("{}", *end.sub(2) as char);
-    /// }
-    /// ```
-    #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[must_use = "returns a new pointer rather than modifying its argument"]
-    #[rustc_const_unstable(feature = "const_ptr_offset", issue = "71499")]
-    #[inline]
-    pub const unsafe fn sub(self, count: usize) -> Self
-    where
-        T: Sized,
-    {
-        // SAFETY: the caller must uphold the safety contract for `offset`.
-        unsafe { self.offset((count as isize).wrapping_neg()) }
-    }
-
-    /// Calculates the offset from a pointer using wrapping arithmetic.
-    /// (convenience for `.wrapping_offset(count as isize)`)
-    ///
-    /// `count` is in units of T; e.g., a `count` of 3 represents a pointer
-    /// offset of `3 * size_of::<T>()` bytes.
-    ///
-    /// # Safety
-    ///
-    /// The resulting pointer does not need to be in bounds, but it is
-    /// potentially hazardous to dereference (which requires `unsafe`).
-    ///
-    /// In particular, the resulting pointer remains attached to the same allocated
-    /// object that `self` points to. It may *not* be used to access a
-    /// different allocated object. Note that in Rust,
-    /// every (stack-allocated) variable is considered a separate allocated object.
-    ///
-    /// Compared to [`add`], this method basically delays the requirement of staying
-    /// within the same allocated object: [`add`] is immediate Undefined Behavior when
-    /// crossing object boundaries; `wrapping_add` produces a pointer but still leads
-    /// to Undefined Behavior if that pointer is dereferenced. [`add`] can be optimized
-    /// better and is thus preferable in performance-sensitive code.
-    ///
-    /// If you need to cross object boundaries, cast the pointer to an integer and
-    /// do the arithmetic there.
-    ///
-    /// [`add`]: #method.add
-    ///
-    /// # Examples
-    ///
-    /// Basic usage:
-    ///
-    /// ```
-    /// // Iterate using a raw pointer in increments of two elements
-    /// let data = [1u8, 2, 3, 4, 5];
-    /// let mut ptr: *const u8 = data.as_ptr();
-    /// let step = 2;
-    /// let end_rounded_up = ptr.wrapping_add(6);
-    ///
-    /// // This loop prints "1, 3, 5, "
-    /// while ptr != end_rounded_up {
-    ///     unsafe {
-    ///         print!("{}, ", *ptr);
-    ///     }
-    ///     ptr = ptr.wrapping_add(step);
-    /// }
-    /// ```
-    #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[must_use = "returns a new pointer rather than modifying its argument"]
-    #[rustc_const_unstable(feature = "const_ptr_offset", issue = "71499")]
-    #[inline]
-    pub const fn wrapping_add(self, count: usize) -> Self
-    where
-        T: Sized,
-    {
-        self.wrapping_offset(count as isize)
-    }
-
-    /// Calculates the offset from a pointer using wrapping arithmetic.
-    /// (convenience for `.wrapping_offset((count as isize).wrapping_sub())`)
-    ///
-    /// `count` is in units of T; e.g., a `count` of 3 represents a pointer
-    /// offset of `3 * size_of::<T>()` bytes.
-    ///
-    /// # Safety
-    ///
-    /// The resulting pointer does not need to be in bounds, but it is
-    /// potentially hazardous to dereference (which requires `unsafe`).
-    ///
-    /// In particular, the resulting pointer remains attached to the same allocated
-    /// object that `self` points to. It may *not* be used to access a
-    /// different allocated object. Note that in Rust,
-    /// every (stack-allocated) variable is considered a separate allocated object.
-    ///
-    /// Compared to [`sub`], this method basically delays the requirement of staying
-    /// within the same allocated object: [`sub`] is immediate Undefined Behavior when
-    /// crossing object boundaries; `wrapping_sub` produces a pointer but still leads
-    /// to Undefined Behavior if that pointer is dereferenced. [`sub`] can be optimized
-    /// better and is thus preferable in performance-sensitive code.
-    ///
-    /// If you need to cross object boundaries, cast the pointer to an integer and
-    /// do the arithmetic there.
-    ///
-    /// [`sub`]: #method.sub
-    ///
-    /// # Examples
-    ///
-    /// Basic usage:
-    ///
-    /// ```
-    /// // Iterate using a raw pointer in increments of two elements (backwards)
-    /// let data = [1u8, 2, 3, 4, 5];
-    /// let mut ptr: *const u8 = data.as_ptr();
-    /// let start_rounded_down = ptr.wrapping_sub(2);
-    /// ptr = ptr.wrapping_add(4);
-    /// let step = 2;
-    /// // This loop prints "5, 3, 1, "
-    /// while ptr != start_rounded_down {
-    ///     unsafe {
-    ///         print!("{}, ", *ptr);
-    ///     }
-    ///     ptr = ptr.wrapping_sub(step);
-    /// }
-    /// ```
-    #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[must_use = "returns a new pointer rather than modifying its argument"]
-    #[rustc_const_unstable(feature = "const_ptr_offset", issue = "71499")]
-    #[inline]
-    pub const fn wrapping_sub(self, count: usize) -> Self
-    where
-        T: Sized,
-    {
-        self.wrapping_offset((count as isize).wrapping_neg())
-    }
-
-    /// Reads the value from `self` without moving it. This leaves the
-    /// memory in `self` unchanged.
-    ///
-    /// See [`ptr::read`] for safety concerns and examples.
-    ///
-    /// [`ptr::read`]: ./ptr/fn.read.html
-    #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[inline]
-    pub unsafe fn read(self) -> T
-    where
-        T: Sized,
-    {
-        // SAFETY: the caller must uphold the safety contract for `read`.
-        unsafe { read(self) }
-    }
-
-    /// Performs a volatile read of the value from `self` without moving it. This
-    /// leaves the memory in `self` unchanged.
-    ///
-    /// Volatile operations are intended to act on I/O memory, and are guaranteed
-    /// to not be elided or reordered by the compiler across other volatile
-    /// operations.
-    ///
-    /// See [`ptr::read_volatile`] for safety concerns and examples.
-    ///
-    /// [`ptr::read_volatile`]: ./ptr/fn.read_volatile.html
-    #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[inline]
-    pub unsafe fn read_volatile(self) -> T
-    where
-        T: Sized,
-    {
-        // SAFETY: the caller must uphold the safety contract for `read_volatile`.
-        unsafe { read_volatile(self) }
-    }
-
-    /// Reads the value from `self` without moving it. This leaves the
-    /// memory in `self` unchanged.
-    ///
-    /// Unlike `read`, the pointer may be unaligned.
-    ///
-    /// See [`ptr::read_unaligned`] for safety concerns and examples.
-    ///
-    /// [`ptr::read_unaligned`]: ./ptr/fn.read_unaligned.html
-    #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[inline]
-    pub unsafe fn read_unaligned(self) -> T
-    where
-        T: Sized,
-    {
-        // SAFETY: the caller must uphold the safety contract for `read_unaligned`.
-        unsafe { read_unaligned(self) }
-    }
-
-    /// Copies `count * size_of<T>` bytes from `self` to `dest`. The source
-    /// and destination may overlap.
-    ///
-    /// NOTE: this has the *same* argument order as [`ptr::copy`].
-    ///
-    /// See [`ptr::copy`] for safety concerns and examples.
-    ///
-    /// [`ptr::copy`]: ./ptr/fn.copy.html
-    #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[inline]
-    pub unsafe fn copy_to(self, dest: *mut T, count: usize)
-    where
-        T: Sized,
-    {
-        // SAFETY: the caller must uphold the safety contract for `copy`.
-        unsafe { copy(self, dest, count) }
-    }
-
-    /// Copies `count * size_of<T>` bytes from `self` to `dest`. The source
-    /// and destination may *not* overlap.
-    ///
-    /// NOTE: this has the *same* argument order as [`ptr::copy_nonoverlapping`].
-    ///
-    /// See [`ptr::copy_nonoverlapping`] for safety concerns and examples.
-    ///
-    /// [`ptr::copy_nonoverlapping`]: ./ptr/fn.copy_nonoverlapping.html
-    #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[inline]
-    pub unsafe fn copy_to_nonoverlapping(self, dest: *mut T, count: usize)
-    where
-        T: Sized,
-    {
-        // SAFETY: the caller must uphold the safety contract for `copy_nonoverlapping`.
-        unsafe { copy_nonoverlapping(self, dest, count) }
-    }
-
-    /// Computes the offset that needs to be applied to the pointer in order to make it aligned to
-    /// `align`.
-    ///
-    /// If it is not possible to align the pointer, the implementation returns
-    /// `usize::MAX`. It is permissible for the implementation to *always*
-    /// return `usize::MAX`. Only your algorithm's performance can depend
-    /// on getting a usable offset here, not its correctness.
-    ///
-    /// The offset is expressed in number of `T` elements, and not bytes. The value returned can be
-    /// used with the `wrapping_add` method.
-    ///
-    /// There are no guarantees whatsoever that offsetting the pointer will not overflow or go
-    /// beyond the allocation that the pointer points into. It is up to the caller to ensure that
-    /// the returned offset is correct in all terms other than alignment.
-    ///
-    /// # Panics
-    ///
-    /// The function panics if `align` is not a power-of-two.
-    ///
-    /// # Examples
-    ///
-    /// Accessing adjacent `u8` as `u16`
-    ///
-    /// ```
-    /// # fn foo(n: usize) {
-    /// # use std::mem::align_of;
-    /// # unsafe {
-    /// let x = [5u8, 6u8, 7u8, 8u8, 9u8];
-    /// let ptr = &x[n] as *const u8;
-    /// let offset = ptr.align_offset(align_of::<u16>());
-    /// if offset < x.len() - n - 1 {
-    ///     let u16_ptr = ptr.add(offset) as *const u16;
-    ///     assert_ne!(*u16_ptr, 500);
-    /// } else {
-    ///     // while the pointer can be aligned via `offset`, it would point
-    ///     // outside the allocation
-    /// }
-    /// # } }
-    /// ```
-    #[stable(feature = "align_offset", since = "1.36.0")]
-    pub fn align_offset(self, align: usize) -> usize
-    where
-        T: Sized,
-    {
-        if !align.is_power_of_two() {
-            panic!("align_offset: align is not a power-of-two");
-        }
-        // SAFETY: `align` has been checked to be a power of 2 above
-        unsafe { align_offset(self, align) }
-    }
-}
-
-#[lang = "const_slice_ptr"]
-impl<T> *const [T] {
-    /// Returns the length of a raw slice.
-    ///
-    /// The returned value is the number of **elements**, not the number of bytes.
-    ///
-    /// This function is safe, even when the raw slice cannot be cast to a slice
-    /// reference because the pointer is null or unaligned.
-    ///
-    /// # Examples
-    ///
-    /// ```rust
-    /// #![feature(slice_ptr_len)]
-    ///
-    /// use std::ptr;
-    ///
-    /// let slice: *const [i8] = ptr::slice_from_raw_parts(ptr::null(), 3);
-    /// assert_eq!(slice.len(), 3);
-    /// ```
-    #[inline]
-    #[unstable(feature = "slice_ptr_len", issue = "71146")]
-    #[rustc_const_unstable(feature = "const_slice_ptr_len", issue = "71146")]
-    pub const fn len(self) -> usize {
-        // SAFETY: this is safe because `*const [T]` and `FatPtr<T>` have the same layout.
-        // Only `std` can make this guarantee.
-        unsafe { Repr { rust: self }.raw }.len
-    }
-
-    /// Returns a raw pointer to the slice's buffer.
-    ///
-    /// This is equivalent to casting `self` to `*const T`, but more type-safe.
-    ///
-    /// # Examples
-    ///
-    /// ```rust
-    /// #![feature(slice_ptr_get)]
-    /// use std::ptr;
-    ///
-    /// let slice: *const [i8] = ptr::slice_from_raw_parts(ptr::null(), 3);
-    /// assert_eq!(slice.as_ptr(), 0 as *const i8);
-    /// ```
-    #[inline]
-    #[unstable(feature = "slice_ptr_get", issue = "74265")]
-    #[rustc_const_unstable(feature = "slice_ptr_get", issue = "74265")]
-    pub const fn as_ptr(self) -> *const T {
-        self as *const T
-    }
-
-    /// Returns a raw pointer to an element or subslice, without doing bounds
-    /// checking.
-    ///
-    /// Calling this method with an out-of-bounds index or when `self` is not dereferencable
-    /// is *[undefined behavior]* even if the resulting pointer is not used.
-    ///
-    /// [undefined behavior]: https://doc.rust-lang.org/reference/behavior-considered-undefined.html
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// #![feature(slice_ptr_get)]
-    ///
-    /// let x = &[1, 2, 4] as *const [i32];
-    ///
-    /// unsafe {
-    ///     assert_eq!(x.get_unchecked(1), x.as_ptr().add(1));
-    /// }
-    /// ```
-    #[unstable(feature = "slice_ptr_get", issue = "74265")]
-    #[inline]
-    pub unsafe fn get_unchecked<I>(self, index: I) -> *const I::Output
-    where
-        I: SliceIndex<[T]>,
-    {
-        // SAFETY: the caller ensures that `self` is dereferencable and `index` in-bounds.
-        unsafe { index.get_unchecked(self) }
-    }
-}
-
-// Equality for pointers
-#[stable(feature = "rust1", since = "1.0.0")]
-impl<T: ?Sized> PartialEq for *const T {
-    #[inline]
-    fn eq(&self, other: &*const T) -> bool {
-        *self == *other
-    }
-}
-
-#[stable(feature = "rust1", since = "1.0.0")]
-impl<T: ?Sized> Eq for *const T {}
-
-// Comparison for pointers
-#[stable(feature = "rust1", since = "1.0.0")]
-impl<T: ?Sized> Ord for *const T {
-    #[inline]
-    fn cmp(&self, other: &*const T) -> Ordering {
-        if self < other {
-            Less
-        } else if self == other {
-            Equal
-        } else {
-            Greater
-        }
-    }
-}
-
-#[stable(feature = "rust1", since = "1.0.0")]
-impl<T: ?Sized> PartialOrd for *const T {
-    #[inline]
-    fn partial_cmp(&self, other: &*const T) -> Option<Ordering> {
-        Some(self.cmp(other))
-    }
-
-    #[inline]
-    fn lt(&self, other: &*const T) -> bool {
-        *self < *other
-    }
-
-    #[inline]
-    fn le(&self, other: &*const T) -> bool {
-        *self <= *other
-    }
-
-    #[inline]
-    fn gt(&self, other: &*const T) -> bool {
-        *self > *other
-    }
-
-    #[inline]
-    fn ge(&self, other: &*const T) -> bool {
-        *self >= *other
-    }
-}