Struct Layout

#[repr(C)]
pub struct Layout {
    pub size: usize,
    pub align: usize,
}

ABI-stable equivalent of std::mem::Layout

Fields

size: usize

The expected size of the allocation.

align: usize

The expected alignment of the allocation.

Implementations

impl Layout

where Struct<FieldPair<usize, usize>>: IStable, usize: IStable,

pub const fn has_optimal_layout() -> bool

Returns true if the layout for Layout is smaller or equal to that Rust would have generated for it.

impl Layout

pub const fn of<T: Sized>() -> Self

Returns the Layout corresponding to T

pub const fn array<T: Sized>(n: usize) -> Self

Returns the Layout corresponding to [T; n].

Note that while this ensures that even if T’s size is not a multiple of its alignment, the layout will have sufficient memory to store n of T in an aligned fashion.

pub const fn concat(self, other: Self) -> Self

Concatenates a layout to self, ensuring that alignment padding is taken into account.

pub fn next_matching<T>(self, ptr: *mut T) -> *mut T

Returns the first pointer where output >= ptr such that output % self.align == 0.

pub const fn realign(self, new_align: usize) -> Self

Changes the alignment of the layout, adding padding if necessary.

Trait Implementations

impl Clone for Layout

fn clone(&self) -> Layout

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Layout

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Hash for Layout

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl IStable for Layout

where Struct<FieldPair<usize, usize>>: IStable, usize: IStable,

const REPORT: &'static TypeReport

A compile-time generated report of the fields of the type, allowing for compatibility inspection.

const ID: u64 = 4_359_646_995_240_167_857u64

A stable (and ideally unique) identifier for the type. Often generated using crate::report::gen_id, but can be manually set.

type ForbiddenValues = <Struct<FieldPair<usize, usize>> as IStable>::ForbiddenValues

The values that the annotated type cannot occupy.

type UnusedBits = <Struct<FieldPair<usize, usize>> as IStable>::UnusedBits

The padding bits in the annotated types

type Size = <Struct<FieldPair<usize, usize>> as IStable>::Size

The size of the annotated type in bytes.

type Align = <Struct<FieldPair<usize, usize>> as IStable>::Align

The alignment of the annotated type in bytes.

type HasExactlyOneNiche = <Struct<FieldPair<usize, usize>> as IStable>::HasExactlyOneNiche

Allows the detection of whether or not core::option::Options are stable:

type ContainsIndirections = <Struct<FieldPair<usize, usize>> as IStable>::ContainsIndirections

Whether or not the type contains indirections (pointers, indices in independent data-structures…)

fn size() -> usize

Returns the size of the type.

fn align() -> usize

Returns the alignment of the type.

unsafe fn is_invalid(ptr: *const u8) -> bool

Returns true if ptr points to memory that cannot be a valid value of Self.

impl Ord for Layout

fn cmp(&self, other: &Layout) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Layout

fn eq(&self, other: &Layout) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Layout

fn partial_cmp(&self, other: &Layout) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Copy for Layout

impl Eq for Layout

impl StructuralPartialEq for Layout