Function rustc_codegen_ssa::back::write::start_async_codegen

pub fn start_async_codegen<B: ExtraBackendMethods>(
    backend: B,
    tcx: TyCtxt<'_>,
    target_cpu: String,
    metadata: EncodedMetadata,
    metadata_module: Option<CompiledModule>,
    total_cgus: usize
) -> OngoingCodegen<B>