Auto merge of #114481 - matthiaskrgr:rollup-58pczpl, r=matthiaskrgr

Rollup of 9 pull requests

Successful merges:

 - #113945 (Fix wrong span for trait selection failure error reporting)
 - #114351 ([rustc_span][perf] Remove unnecessary string joins and allocs.)
 - #114418 (bump parking_lot to 0.12)
 - #114434 (Improve spans for indexing expressions)
 - #114450 (Fix ICE failed to get layout for ReferencesError)
 - #114461 (Fix unwrap on None)
 - #114462 (interpret: add mplace_to_ref helper method)
 - #114472 (Reword `confusable_idents` lint)
 - #114477 (Account for `Rc` and `Arc` when suggesting to clone)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

Cargo.lock

@@ -3469,7 +3469,7 @@ dependencies = [
  "libc",
  "measureme",
  "memmap2",
- "parking_lot 0.11.2",
+ "parking_lot 0.12.1",
  "rustc-hash",
  "rustc-rayon",
  "rustc-rayon-core",
@@ -4190,7 +4190,7 @@ dependencies = [
 name = "rustc_query_system"
 version = "0.0.0"
 dependencies = [
- "parking_lot 0.11.2",
+ "parking_lot 0.12.1",
  "rustc-rayon-core",
  "rustc_ast",
  "rustc_data_structures",

compiler/rustc_ast/src/ast.rs

@@ -1462,7 +1462,8 @@ pub enum ExprKind {
     /// Access of a named (e.g., `obj.foo`) or unnamed (e.g., `obj.0`) struct field.
     Field(P<Expr>, Ident),
     /// An indexing operation (e.g., `foo[2]`).
-    Index(P<Expr>, P<Expr>),
+    /// The span represents the span of the `[2]`, including brackets.
+    Index(P<Expr>, P<Expr>, Span),
     /// A range (e.g., `1..2`, `1..`, `..2`, `1..=2`, `..=2`; and `..` in destructuring assignment).
     Range(Option<P<Expr>>, Option<P<Expr>>, RangeLimits),
     /// An underscore, used in destructuring assignment to ignore a value.

compiler/rustc_ast/src/mut_visit.rs

@@ -1400,14 +1400,15 @@ pub fn noop_visit_expr<T: MutVisitor>(
             fn_decl,
             body,
             fn_decl_span,
-            fn_arg_span: _,
+            fn_arg_span,
         }) => {
             vis.visit_closure_binder(binder);
             visit_constness(constness, vis);
             vis.visit_asyncness(asyncness);
             vis.visit_fn_decl(fn_decl);
             vis.visit_expr(body);
             vis.visit_span(fn_decl_span);
+            vis.visit_span(fn_arg_span);
         }
         ExprKind::Block(blk, label) => {
             vis.visit_block(blk);
@@ -1420,9 +1421,10 @@ pub fn noop_visit_expr<T: MutVisitor>(
             vis.visit_expr(expr);
             vis.visit_span(await_kw_span);
         }
-        ExprKind::Assign(el, er, _) => {
+        ExprKind::Assign(el, er, span) => {
             vis.visit_expr(el);
             vis.visit_expr(er);
+            vis.visit_span(span);
         }
         ExprKind::AssignOp(_op, el, er) => {
             vis.visit_expr(el);
@@ -1432,9 +1434,10 @@ pub fn noop_visit_expr<T: MutVisitor>(
             vis.visit_expr(el);
             vis.visit_ident(ident);
         }
-        ExprKind::Index(el, er) => {
+        ExprKind::Index(el, er, brackets_span) => {
             vis.visit_expr(el);
             vis.visit_expr(er);
+            vis.visit_span(brackets_span);
         }
         ExprKind::Range(e1, e2, _lim) => {
             visit_opt(e1, |e1| vis.visit_expr(e1));

compiler/rustc_ast/src/util/parser.rs

@@ -390,7 +390,7 @@ pub fn contains_exterior_struct_lit(value: &ast::Expr) -> bool {
         | ast::ExprKind::Cast(x, _)
         | ast::ExprKind::Type(x, _)
         | ast::ExprKind::Field(x, _)
-        | ast::ExprKind::Index(x, _) => {
+        | ast::ExprKind::Index(x, _, _) => {
             // &X { y: 1 }, X { y: 1 }.y
             contains_exterior_struct_lit(x)
         }

compiler/rustc_ast/src/visit.rs

@@ -885,7 +885,7 @@ pub fn walk_expr<'a, V: Visitor<'a>>(visitor: &mut V, expression: &'a Expr) {
             visitor.visit_expr(subexpression);
             visitor.visit_ident(*ident);
         }
-        ExprKind::Index(main_expression, index_expression) => {
+        ExprKind::Index(main_expression, index_expression, _) => {
             visitor.visit_expr(main_expression);
             visitor.visit_expr(index_expression)
         }

compiler/rustc_ast_lowering/src/expr.rs

@@ -240,8 +240,8 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 ExprKind::Field(el, ident) => {
                     hir::ExprKind::Field(self.lower_expr(el), self.lower_ident(*ident))
                 }
-                ExprKind::Index(el, er) => {
-                    hir::ExprKind::Index(self.lower_expr(el), self.lower_expr(er))
+                ExprKind::Index(el, er, brackets_span) => {
+                    hir::ExprKind::Index(self.lower_expr(el), self.lower_expr(er), *brackets_span)
                 }
                 ExprKind::Range(Some(e1), Some(e2), RangeLimits::Closed) => {
                     self.lower_expr_range_closed(e.span, e1, e2)

compiler/rustc_ast_pretty/src/pprust/state/expr.rs

@@ -477,7 +477,7 @@ impl<'a> State<'a> {
                 self.word(".");
                 self.print_ident(*ident);
             }
-            ast::ExprKind::Index(expr, index) => {
+            ast::ExprKind::Index(expr, index, _) => {
                 self.print_expr_maybe_paren(expr, parser::PREC_POSTFIX);
                 self.word("[");
                 self.print_expr(index);

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -751,9 +751,19 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 )
                 .must_apply_modulo_regions()
         {
+            let msg = if let ty::Adt(def, _) = ty.kind()
+                && [
+                    tcx.get_diagnostic_item(sym::Arc),
+                    tcx.get_diagnostic_item(sym::Rc),
+                ].contains(&Some(def.did()))
+            {
+                "clone the value to increment its reference count"
+            } else {
+                "consider cloning the value if the performance cost is acceptable"
+            };
             err.span_suggestion_verbose(
                 span.shrink_to_hi(),
-                "consider cloning the value if the performance cost is acceptable",
+                msg,
                 suggestion,
                 Applicability::MachineApplicable,
             );

compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs

@@ -79,7 +79,7 @@ impl<'tcx> BorrowExplanation<'tcx> {
                         | hir::ExprKind::Unary(hir::UnOp::Deref, inner)
                         | hir::ExprKind::Field(inner, _)
                         | hir::ExprKind::MethodCall(_, inner, _, _)
-                        | hir::ExprKind::Index(inner, _) = &expr.kind
+                        | hir::ExprKind::Index(inner, _, _) = &expr.kind
                     {
                         expr = inner;
                     }

compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs

@@ -567,7 +567,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                         }
                     };
                     if let hir::ExprKind::Assign(place, rv, _sp) = expr.kind
-                        && let hir::ExprKind::Index(val, index) = place.kind
+                        && let hir::ExprKind::Index(val, index, _) = place.kind
                         && (expr.span == self.assign_span || place.span == self.assign_span)
                     {
                         // val[index] = rv;
@@ -620,7 +620,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                         );
                         self.suggested = true;
                     } else if let hir::ExprKind::MethodCall(_path, receiver, _, sp) = expr.kind
-                        && let hir::ExprKind::Index(val, index) = receiver.kind
+                        && let hir::ExprKind::Index(val, index, _) = receiver.kind
                         && expr.span == self.assign_span
                     {
                         // val[index].path(args..);