//! Support for serializing the dep-graph and reloading it.
#![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
+// this shouldn't be necessary, but the check for `&mut _` is too naive and denies returning a function pointer that takes a mut ref
+#![feature(const_mut_refs)]
#![feature(min_specialization)]
#![feature(never_type)]
#![feature(once_cell)]
use rustc_data_structures::sync::AtomicU64;
use rustc_middle::arena::Arena;
-use rustc_middle::dep_graph::{self, DepKindStruct, SerializedDepNodeIndex};
+use rustc_middle::dep_graph::{self, DepKindStruct};
use rustc_middle::ty::query::{query_keys, query_storage, query_stored, query_values};
use rustc_middle::ty::query::{ExternProviders, Providers, QueryEngine};
use rustc_middle::ty::{self, TyCtxt};