Struct rustc_errors::diagnostic_builder::DiagnosticBuilderInner

struct DiagnosticBuilderInner<'a> {
    state: DiagnosticBuilderState<'a>,
    diagnostic: Box<Diagnostic>,
}

This type exists only for DiagnosticBuilder::forget_guarantee, because it:

1. lacks the G parameter and therefore DiagnosticBuilder<G1> can be converted into DiagnosticBuilder<G2> while reusing the inner field
2. can implement the Drop “bomb” instead of DiagnosticBuilder, as it contains all of the data (state + diagnostic) of DiagnosticBuilder

The diagnostic field is not Copy and can’t be moved out of whichever type implements the Drop “bomb”, but because of the above two facts, that never needs to happen - instead, the whole inner: DiagnosticBuilderInner can be moved out of a DiagnosticBuilder and into another.

Fields

state: DiagnosticBuilderState<'a>

diagnostic: Box<Diagnostic>

Diagnostic is a large type, and DiagnosticBuilder is often used as a return value, especially within the frequently-used PResult type. In theory, return value optimization (RVO) should avoid unnecessary copying. In practice, it does not (at the time of writing).

Trait Implementations

impl<'a> Clone for DiagnosticBuilderInner<'a>

fn clone(&self) -> DiagnosticBuilderInner<'a>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Drop for DiagnosticBuilderInner<'_>

Destructor bomb - a DiagnosticBuilder must be either emitted or cancelled or we emit a bug.

fn drop(&mut self)

Executes the destructor for this type.

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