offset_from / sub_ptr docs: emphasize that pointers must be in the same allocation

This commit is contained in:
Ralf Jung 2024-11-01 15:30:08 +01:00
parent aba2088735
commit c38865502e
3 changed files with 12 additions and 12 deletions

View File

@ -582,7 +582,7 @@ impl<T: ?Sized> *const T {
intrinsics::ptr_mask(self.cast::<()>(), mask).with_metadata_of(self)
}
/// Calculates the distance between two pointers. The returned value is in
/// Calculates the distance between two pointers within the same allocation. The returned value is in
/// units of T: the distance in bytes divided by `mem::size_of::<T>()`.
///
/// This is equivalent to `(self as isize - origin as isize) / (mem::size_of::<T>() as isize)`,
@ -677,7 +677,7 @@ impl<T: ?Sized> *const T {
unsafe { intrinsics::ptr_offset_from(self, origin) }
}
/// Calculates the distance between two pointers. The returned value is in
/// Calculates the distance between two pointers within the same allocation. The returned value is in
/// units of **bytes**.
///
/// This is purely a convenience for casting to a `u8` pointer and
@ -695,7 +695,7 @@ impl<T: ?Sized> *const T {
unsafe { self.cast::<u8>().offset_from(origin.cast::<u8>()) }
}
/// Calculates the distance between two pointers, *where it's known that
/// Calculates the distance between two pointers within the same allocation, *where it's known that
/// `self` is equal to or greater than `origin`*. The returned value is in
/// units of T: the distance in bytes is divided by `mem::size_of::<T>()`.
///
@ -790,7 +790,7 @@ impl<T: ?Sized> *const T {
unsafe { intrinsics::ptr_offset_from_unsigned(self, origin) }
}
/// Calculates the distance between two pointers, *where it's known that
/// Calculates the distance between two pointers within the same allocation, *where it's known that
/// `self` is equal to or greater than `origin`*. The returned value is in
/// units of **bytes**.
///

View File

@ -746,7 +746,7 @@ impl<T: ?Sized> *mut T {
(self as *const T).guaranteed_ne(other as _)
}
/// Calculates the distance between two pointers. The returned value is in
/// Calculates the distance between two pointers within the same allocation. The returned value is in
/// units of T: the distance in bytes divided by `mem::size_of::<T>()`.
///
/// This is equivalent to `(self as isize - origin as isize) / (mem::size_of::<T>() as isize)`,
@ -839,7 +839,7 @@ impl<T: ?Sized> *mut T {
unsafe { (self as *const T).offset_from(origin) }
}
/// Calculates the distance between two pointers. The returned value is in
/// Calculates the distance between two pointers within the same allocation. The returned value is in
/// units of **bytes**.
///
/// This is purely a convenience for casting to a `u8` pointer and
@ -857,7 +857,7 @@ impl<T: ?Sized> *mut T {
unsafe { self.cast::<u8>().offset_from(origin.cast::<u8>()) }
}
/// Calculates the distance between two pointers, *where it's known that
/// Calculates the distance between two pointers within the same allocation, *where it's known that
/// `self` is equal to or greater than `origin`*. The returned value is in
/// units of T: the distance in bytes is divided by `mem::size_of::<T>()`.
///
@ -930,7 +930,7 @@ impl<T: ?Sized> *mut T {
unsafe { (self as *const T).sub_ptr(origin) }
}
/// Calculates the distance between two pointers, *where it's known that
/// Calculates the distance between two pointers within the same allocation, *where it's known that
/// `self` is equal to or greater than `origin`*. The returned value is in
/// units of **bytes**.
///

View File

@ -676,7 +676,7 @@ impl<T: ?Sized> NonNull<T> {
unsafe { NonNull { pointer: self.pointer.byte_sub(count) } }
}
/// Calculates the distance between two pointers. The returned value is in
/// Calculates the distance between two pointers within the same allocation. The returned value is in
/// units of T: the distance in bytes divided by `mem::size_of::<T>()`.
///
/// This is equivalent to `(self as isize - origin as isize) / (mem::size_of::<T>() as isize)`,
@ -773,7 +773,7 @@ impl<T: ?Sized> NonNull<T> {
unsafe { self.pointer.offset_from(origin.pointer) }
}
/// Calculates the distance between two pointers. The returned value is in
/// Calculates the distance between two pointers within the same allocation. The returned value is in
/// units of **bytes**.
///
/// This is purely a convenience for casting to a `u8` pointer and
@ -793,7 +793,7 @@ impl<T: ?Sized> NonNull<T> {
// N.B. `wrapping_offset``, `wrapping_add`, etc are not implemented because they can wrap to null
/// Calculates the distance between two pointers, *where it's known that
/// Calculates the distance between two pointers within the same allocation, *where it's known that
/// `self` is equal to or greater than `origin`*. The returned value is in
/// units of T: the distance in bytes is divided by `mem::size_of::<T>()`.
///
@ -866,7 +866,7 @@ impl<T: ?Sized> NonNull<T> {
unsafe { self.pointer.sub_ptr(subtracted.pointer) }
}
/// Calculates the distance between two pointers, *where it's known that
/// Calculates the distance between two pointers within the same allocation, *where it's known that
/// `self` is equal to or greater than `origin`*. The returned value is in
/// units of **bytes**.
///