Struct Fault 

pub struct Fault { /* private fields */ }

The fault record a RuntimeContext points at. pending_fault is non-null and points at the owning runtime’s slot.

The kind is the whole state. There is no pending: bool mirroring kind != None beside it: one field cannot contradict itself, and generated code branches on the kind word directly (ADR-102).

Implementations

impl Fault

pub const KIND_OFFSET: usize

Where the kind sits within the record, and how wide it is.

Generated code reads the kind directly (ADR-102). An Inst::CheckFault is a load of ctx.pending_fault, a load of the kind at this offset, and a brif — which works only because FaultKind::None is 0 and every raisable kind is not, so the loaded word is Fault::is_pending.

So a repr change to Fault or to FaultKind is a generated-code change and owes a RUNTIME_ABI_VERSION bump. The backend asserts KIND_SIZE at compile time against the width it loads, so a #[repr(u8)] or a #[repr(C)] that grows the enum fails the build rather than reading three bytes of something else.

Both are minted here rather than reached for with offset_of! from the backend because kind is private — the field is private so that Fault::set is the only way to raise, which is what makes “raise no fault” unspellable.

pub const KIND_SIZE: usize

The width of the kind, in bytes. See Fault::KIND_OFFSET.

pub fn clear() -> Self

A fresh, clear fault record (no fault pending).

pub fn set(&mut self, fault: RaisedFault)

Raise fault.

Takes a RaisedFault rather than a FaultKind so that “raise no fault” has no spelling.

pub fn kind(&self) -> FaultKind

The pending fault kind, or FaultKind::None.

pub fn is_pending(&self) -> bool

True iff a fault is pending.

Trait Implementations

impl Default for Fault

fn default() -> Self

Returns the “default value” for a type.