Type Alias TypingMode

pub type TypingMode<'tcx> = TypingMode<TyCtxt<'tcx>>;

Aliased Type

enum TypingMode<'tcx> {
    Coherence,
    Analysis {
        defining_opaque_types: &'tcx RawList<(), LocalDefId>,
    },
    PostAnalysis,
}

Variants

Coherence

When checking whether impls overlap, we check whether any obligations are guaranteed to never hold when unifying the impls. This requires us to be complete: we must never fail to prove something which may actually hold.

In this typing mode we bail with ambiguity in case its not knowable whether a trait goal may hold, e.g. because the trait may get implemented in a downstream or sibling crate.

We also have to be careful when generalizing aliases inside of higher-ranked types to not unnecessarily constrain any inference variables.

Analysis

Analysis includes type inference, checking that items are well-formed, and pretty much everything else which may emit proper type errors to the user.

We only normalize opaque types which may get defined by the current body, which are stored in defining_opaque_types.

Fields

defining_opaque_types: &'tcx RawList<(), LocalDefId>

PostAnalysis

After analysis, mostly during codegen and MIR optimizations, we’re able to reveal all opaque types.

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 16 bytes

Size for each variant:

• Coherence: 0 bytes
• Analysis: 8 bytes
• PostAnalysis: 0 bytes