fn start_executing_work<B: ExtraBackendMethods>(
    backend: B,
    tcx: TyCtxt<'_>,
    crate_info: &CrateInfo,
    shared_emitter: SharedEmitter,
    codegen_worker_send: Sender<CguMessage>,
    coordinator_receive: Receiver<Box<dyn Any + Send>>,
    jobserver: Client,
    regular_config: Arc<ModuleConfig>,
    metadata_config: Arc<ModuleConfig>,
    allocator_config: Arc<ModuleConfig>,
    tx_to_llvm_workers: Sender<Box<dyn Any + Send>>
) -> JoinHandle<Result<CompiledModules, ()>>