Enum CastKind

pub enum CastKind {
    PointerExposeProvenance,
    PointerWithExposedProvenance,
    PointerCoercion(PointerCoercion, CoercionSource),
    IntToInt,
    FloatToInt,
    FloatToFloat,
    IntToFloat,
    PtrToPtr,
    FnPtrToPtr,
    Transmute,
}

Variants

PointerExposeProvenance

An exposing pointer to address cast. A cast between a pointer and an integer type, or between a function pointer and an integer type. See the docs on expose_provenance for more details.

PointerWithExposedProvenance

An address-to-pointer cast that picks up an exposed provenance. See the docs on with_exposed_provenance for more details.

PointerCoercion(PointerCoercion, CoercionSource)

Pointer related casts that are done by coercions. Note that reference-to-raw-ptr casts are translated into &raw mut/const *r, i.e., they are not actually casts.

The following are allowed in AnalysisPhase::Initial as they’re needed for borrowck, but after that are forbidden (including in all phases of runtime MIR):

• PointerCoercion::ArrayToPointer
• PointerCoercion::MutToConstPointer

Both are runtime nops, so should be CastKind::PtrToPtr instead in runtime MIR.

IntToInt

FloatToInt

FloatToFloat

IntToFloat

PtrToPtr

FnPtrToPtr

Transmute

Reinterpret the bits of the input as a different type.

MIR is well-formed if the input and output types have different sizes, but running a transmute between differently-sized types is UB.

Allowed only in MirPhase::Runtime; Earlier it’s a TerminatorKind::Call.