We always use the current item as parent, so no need to pass it

Author: oli-obk

compiler/rustc_ast_lowering/src/expr.rs

@@ -492,9 +492,8 @@ impl<'hir> LoweringContext<'_, 'hir> {
         let mut generic_args = ThinVec::new();
         for (idx, arg) in args.iter().cloned().enumerate() {
             if legacy_args_idx.contains(&idx) {
-                let parent_def_id = self.current_hir_id_owner.def_id;
                 let node_id = self.next_node_id();
-                self.create_def(parent_def_id, node_id, None, DefKind::AnonConst, f.span);
+                self.create_def(node_id, None, DefKind::AnonConst, f.span);
                 let mut visitor = WillCreateDefIdsVisitor {};
                 let const_value = if let ControlFlow::Break(span) = visitor.visit_expr(&arg) {
                     AstP(Expr {

compiler/rustc_ast_lowering/src/lib.rs

@@ -494,12 +494,12 @@ enum GenericArgsMode {
 impl<'a, 'hir> LoweringContext<'a, 'hir> {
     fn create_def(
         &mut self,
-        parent: LocalDefId,
         node_id: ast::NodeId,
         name: Option<Symbol>,
         def_kind: DefKind,
         span: Span,
     ) -> LocalDefId {
+        let parent = self.current_hir_id_owner.def_id;
         debug_assert_ne!(node_id, ast::DUMMY_NODE_ID);
         assert!(
             self.opt_local_def_id(node_id).is_none(),
@@ -781,7 +781,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             LifetimeRes::Fresh { param, kind, .. } => {
                 // Late resolution delegates to us the creation of the `LocalDefId`.
                 let _def_id = self.create_def(
-                    self.current_hir_id_owner.def_id,
                     param,
                     Some(kw::UnderscoreLifetime),
                     DefKind::LifetimeParam,
@@ -2107,16 +2106,14 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             hir::ConstArgKind::Path(qpath)
         } else {
             // Construct an AnonConst where the expr is the "ty"'s path.
-
-            let parent_def_id = self.current_hir_id_owner.def_id;
             let node_id = self.next_node_id();
             let span = self.lower_span(span);
 
             // Add a definition for the in-band const def.
             // We're lowering a const argument that was originally thought to be a type argument,
             // so the def collector didn't create the def ahead of time. That's why we have to do
             // it here.
-            let def_id = self.create_def(parent_def_id, node_id, None, DefKind::AnonConst, span);
+            let def_id = self.create_def(node_id, None, DefKind::AnonConst, span);
             let hir_id = self.lower_node_id(node_id);
 
             let path_expr = Expr {

compiler/rustc_ast_lowering/src/pat.rs

@@ -517,14 +517,13 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         span: Span,
         base_type: Span,
     ) -> &'hir hir::ConstArg<'hir> {
-        let parent_def_id = self.current_hir_id_owner.def_id;
         let node_id = self.next_node_id();
 
         // Add a definition for the in-band const def.
         // We're generating a range end that didn't exist in the AST,
         // so the def collector didn't create the def ahead of time. That's why we have to do
         // it here.
-        let def_id = self.create_def(parent_def_id, node_id, None, DefKind::AnonConst, span);
+        let def_id = self.create_def(node_id, None, DefKind::AnonConst, span);
         let hir_id = self.lower_node_id(node_id);
 
         let unstable_span = self.mark_span_with_reason(