Struct TargetFeature

pub struct TargetFeature {
    pub name: String,
    pub implies_features: Vec<String>,
    pub unstable_feature_gate: Option<String>,
    pub globally_enabled: bool,
}

Information about a target feature.

Rust target features are used to influence code generation, especially around selecting instructions which are not universally supported by the target architecture.

Target features are commonly enabled by the #[target_feature] attribute to influence code generation for a particular function, and less commonly enabled by compiler options like -Ctarget-feature or -Ctarget-cpu. Targets themselves automatically enable certain target features by default, for example because the target’s ABI specification requires saving specific registers which only exist in an architectural extension.

Target features can imply other target features: for example, x86-64 avx2 implies avx, and aarch64 sve2 implies sve, since both of these architectural extensions depend on their predecessors.

Target features can be probed at compile time by #[cfg(target_feature)] or cfg!(…) conditional compilation to determine whether a target feature is enabled in a particular context.

Fields

name: String

The name of this target feature.

implies_features: Vec<String>

Other target features which are implied by this target feature, if any.

unstable_feature_gate: Option<String>

If this target feature is unstable, the name of the associated language feature gate.

globally_enabled: bool

Whether this feature is globally enabled for this compilation session.

Target features can be globally enabled implicitly as a result of the target’s definition. For example, x86-64 hardware floating point ABIs require saving x87 and SSE2 registers, which in turn requires globally enabling the x87 and sse2 target features so that the generated machine code conforms to the target’s ABI.

Target features can also be globally enabled explicitly as a result of compiler flags like -Ctarget-feature or -Ctarget-cpu.

Trait Implementations

impl Clone for TargetFeature

fn clone(&self) -> TargetFeature

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for TargetFeature

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for TargetFeature

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for TargetFeature

fn eq(&self, other: &TargetFeature) -> 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 Serialize for TargetFeature

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for TargetFeature

impl StructuralPartialEq for TargetFeature