Improve the `rustc_data_structures::sync` module doc comment.

Also, `MTRef<'a, T>` is a typedef for a reference to a `T`, but in
practice it's only used (and useful) in combination with `MTLock`, i.e.
`MTRef<'a, MTLock<T>>`. So this commit changes it to be a typedef for a
reference to an `MTLock<T>`, and renames it as `MTLockRef`. I think this
clarifies things, because I found `MTRef` quite puzzling at first.

1 files changed, 5 insertions, 5 deletions

diff --git a/compiler/rustc_monomorphize/src/collector.rs b/compiler/rustc_monomorphize/src/collector.rs
index 98265d58a0a..e24d31c43d3 100644
--- a/compiler/rustc_monomorphize/src/collector.rs
+++ b/compiler/rustc_monomorphize/src/collector.rs
@@ -174,7 +174,7 @@
 //! regardless of whether it is actually needed or not.
 
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
-use rustc_data_structures::sync::{par_for_each_in, MTLock, MTRef};
+use rustc_data_structures::sync::{par_for_each_in, MTLock, MTLockRef};
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, DefIdMap, LocalDefId};
@@ -340,8 +340,8 @@ pub fn collect_crate_mono_items(
     let recursion_limit = tcx.recursion_limit();
 
     {
-        let visited: MTRef<'_, _> = &mut visited;
-        let inlining_map: MTRef<'_, _> = &mut inlining_map;
+        let visited: MTLockRef<'_, _> = &mut visited;
+        let inlining_map: MTLockRef<'_, _> = &mut inlining_map;
 
         tcx.sess.time("monomorphization_collector_graph_walk", || {
             par_for_each_in(roots, |root| {
@@ -406,10 +406,10 @@ fn collect_roots(tcx: TyCtxt<'_>, mode: MonoItemCollectionMode) -> Vec<MonoItem<
 fn collect_items_rec<'tcx>(
     tcx: TyCtxt<'tcx>,
     starting_point: Spanned<MonoItem<'tcx>>,
-    visited: MTRef<'_, MTLock<FxHashSet<MonoItem<'tcx>>>>,
+    visited: MTLockRef<'_, FxHashSet<MonoItem<'tcx>>>,
     recursion_depths: &mut DefIdMap<usize>,
     recursion_limit: Limit,
-    inlining_map: MTRef<'_, MTLock<InliningMap<'tcx>>>,
+    inlining_map: MTLockRef<'_, InliningMap<'tcx>>,
 ) {
     if !visited.lock_mut().insert(starting_point.node) {
         // We've been here already, no need to search again.