Rollup merge of #109354 - Swatinem:rm-closureid, r=compiler-errors

Remove the `NodeId` of `ast::ExprKind::Async`

This is a followup to https://github.com/rust-lang/rust/pull/104833#pullrequestreview-1314537416.

In my original attempt, I was using `LoweringContext::expr`, which was not correct as it creates a fresh `DefId`.
It now uses the correct `DefId` for the wrapping `Expr`, and also makes forwarding `#[track_caller]` attributes more explicit.

compiler/rustc_ast/src/ast.rs

@@ -1426,13 +1426,9 @@ pub enum ExprKind {
     Block(P<Block>, Option<Label>),
     /// An async block (`async move { ... }`).
     ///
-    /// The `NodeId` is the `NodeId` for the closure that results from
-    /// desugaring an async block, just like the NodeId field in the
-    /// `Async::Yes` variant. This is necessary in order to create a def for the
-    /// closure which can be used as a parent of any child defs. Defs
-    /// created during lowering cannot be made the parent of any other
-    /// preexisting defs.
-    Async(CaptureBy, NodeId, P<Block>),
+    /// The async block used to have a `NodeId`, which was removed in favor of
+    /// using the parent `NodeId` of the parent `Expr`.
+    Async(CaptureBy, P<Block>),
     /// An await expression (`my_future.await`).
     Await(P<Expr>),
 

compiler/rustc_ast/src/mut_visit.rs

@@ -1407,8 +1407,7 @@ pub fn noop_visit_expr<T: MutVisitor>(
             vis.visit_block(blk);
             visit_opt(label, |label| vis.visit_label(label));
         }
-        ExprKind::Async(_capture_by, node_id, body) => {
-            vis.visit_id(node_id);
+        ExprKind::Async(_capture_by, body) => {
             vis.visit_block(body);
         }
         ExprKind::Await(expr) => vis.visit_expr(expr),

compiler/rustc_ast/src/visit.rs

@@ -860,7 +860,7 @@ pub fn walk_expr<'a, V: Visitor<'a>>(visitor: &mut V, expression: &'a Expr) {
             walk_list!(visitor, visit_label, opt_label);
             visitor.visit_block(block);
         }
-        ExprKind::Async(_, _, body) => {
+        ExprKind::Async(_, body) => {
             visitor.visit_block(body);
         }
         ExprKind::Await(expr) => visitor.visit_expr(expr),