Struct ReprOptions

pub struct ReprOptions {
    pub int: Option<IntegerType>,
    pub align: Option<Align>,
    pub pack: Option<Align>,
    pub flags: ReprFlags,
    pub field_shuffle_seed: u64,
}

Represents the repr options provided by the user.

Fields

int: Option<IntegerType>

align: Option<Align>

pack: Option<Align>

flags: ReprFlags

field_shuffle_seed: u64

The seed to be used for randomizing a type’s layout

Note: This could technically be a u128 which would be the “most accurate” hash as it’d encompass the item and crate hash without loss, but it does pay the price of being larger. Everything’s a tradeoff, a 64-bit seed should be sufficient for our purposes (primarily -Z randomize-layout)

Implementations

impl ReprOptions

pub fn simd(&self) -> bool

pub fn c(&self) -> bool

pub fn packed(&self) -> bool

pub fn transparent(&self) -> bool

pub fn linear(&self) -> bool

pub fn discr_type(&self) -> IntegerType

Returns the discriminant type, given these repr options. This must only be called on enums!

pub fn inhibit_enum_layout_opt(&self) -> bool

Returns true if this #[repr()] should inhabit “smart enum layout” optimizations, such as representing Foo<&T> as a single pointer.

pub fn inhibit_newtype_abi_optimization(&self) -> bool

pub fn inhibit_struct_field_reordering(&self) -> bool

Returns true if this #[repr()] guarantees a fixed field order, e.g. repr(C) or repr(<int>).

pub fn can_randomize_type_layout(&self) -> bool

Returns true if this type is valid for reordering and -Z randomize-layout was enabled for its declaration crate.

pub fn inhibits_union_abi_opt(&self) -> bool

Returns true if this #[repr()] should inhibit union ABI optimisations.

Trait Implementations

impl Clone for ReprOptions

fn clone(&self) -> ReprOptions

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ReprOptions

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

Formats the value using the given formatter.

impl Default for ReprOptions

fn default() -> ReprOptions

Returns the “default value” for a type.

impl PartialEq for ReprOptions

fn eq(&self, other: &ReprOptions) -> 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 Copy for ReprOptions

impl Eq for ReprOptions

impl StructuralPartialEq for ReprOptions