Merging upstream version 1.69.0+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

8 files changed, 222 insertions, 144 deletions

diff --git a/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
index 1550958ab..68205fa45 100644
--- a/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
@@ -106,7 +106,7 @@ impl<'tcx> ToUniverseInfo<'tcx>
     }
 }
 
-impl<'tcx, T: Copy + fmt::Display + TypeFoldable<'tcx> + 'tcx> ToUniverseInfo<'tcx>
+impl<'tcx, T: Copy + fmt::Display + TypeFoldable<TyCtxt<'tcx>> + 'tcx> ToUniverseInfo<'tcx>
     for Canonical<'tcx, ty::ParamEnvAnd<'tcx, type_op::Normalize<T>>>
 {
     fn to_universe_info(self, base_universe: ty::UniverseIndex) -> UniverseInfo<'tcx> {
@@ -180,20 +180,20 @@ trait TypeOpInfo<'tcx> {
             return;
         };
 
-        let placeholder_region = tcx.mk_region(ty::RePlaceholder(ty::Placeholder {
+        let placeholder_region = tcx.mk_re_placeholder(ty::Placeholder {
             name: placeholder.name,
             universe: adjusted_universe.into(),
-        }));
+        });
 
         let error_region =
             if let RegionElement::PlaceholderRegion(error_placeholder) = error_element {
                 let adjusted_universe =
                     error_placeholder.universe.as_u32().checked_sub(base_universe.as_u32());
                 adjusted_universe.map(|adjusted| {
-                    tcx.mk_region(ty::RePlaceholder(ty::Placeholder {
+                    tcx.mk_re_placeholder(ty::Placeholder {
                         name: error_placeholder.name,
                         universe: adjusted.into(),
-                    }))
+                    })
                 })
             } else {
                 None
@@ -258,7 +258,7 @@ struct NormalizeQuery<'tcx, T> {
 
 impl<'tcx, T> TypeOpInfo<'tcx> for NormalizeQuery<'tcx, T>
 where
-    T: Copy + fmt::Display + TypeFoldable<'tcx> + 'tcx,
+    T: Copy + fmt::Display + TypeFoldable<TyCtxt<'tcx>> + 'tcx,
 {
     fn fallback_error(
         &self,
@@ -390,7 +390,7 @@ fn try_extract_error_from_fulfill_cx<'tcx>(
         error_region,
         &region_constraints,
         |vid| ocx.infcx.region_var_origin(vid),
-        |vid| ocx.infcx.universe_of_region(ocx.infcx.tcx.mk_region(ty::ReVar(vid))),
+        |vid| ocx.infcx.universe_of_region(ocx.infcx.tcx.mk_re_var(vid)),
     )
 }
 
@@ -411,7 +411,7 @@ fn try_extract_error_from_region_constraints<'tcx>(
                 }
                 // FIXME: Should this check the universe of the var?
                 Constraint::VarSubReg(vid, sup) if sup == placeholder_region => {
-                    Some((infcx.tcx.mk_region(ty::ReVar(vid)), cause.clone()))
+                    Some((infcx.tcx.mk_re_var(vid), cause.clone()))
                 }
                 _ => None,
             }
diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
index e5a36259f..cb97699d7 100644
--- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -6,7 +6,7 @@ use rustc_errors::{
     struct_span_err, Applicability, Diagnostic, DiagnosticBuilder, ErrorGuaranteed, MultiSpan,
 };
 use rustc_hir as hir;
-use rustc_hir::def::Res;
+use rustc_hir::def::{DefKind, Res};
 use rustc_hir::intravisit::{walk_block, walk_expr, Visitor};
 use rustc_hir::{AsyncGeneratorKind, GeneratorKind, LangItem};
 use rustc_infer::infer::TyCtxtInferExt;
@@ -236,10 +236,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             let ty = used_place.ty(self.body, self.infcx.tcx).ty;
             let needs_note = match ty.kind() {
                 ty::Closure(id, _) => {
-                    let tables = self.infcx.tcx.typeck(id.expect_local());
-                    let hir_id = self.infcx.tcx.hir().local_def_id_to_hir_id(id.expect_local());
-
-                    tables.closure_kind_origins().get(hir_id).is_none()
+                    self.infcx.tcx.closure_kind_origin(id.expect_local()).is_none()
                 }
                 _ => true,
             };
@@ -766,7 +763,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let copy_did = infcx.tcx.require_lang_item(LangItem::Copy, Some(span));
         let cause = ObligationCause::new(
             span,
-            self.mir_hir_id(),
+            self.mir_def_id(),
             rustc_infer::traits::ObligationCauseCode::MiscObligation,
         );
         let errors = rustc_trait_selection::traits::fully_solve_bound(
@@ -803,6 +800,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 predicates
                     .iter()
                     .map(|(param, constraint)| (param.name.as_str(), &**constraint, None)),
+                None,
             );
         }
     }
@@ -1185,11 +1183,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 return None;
             };
             debug!("checking call args for uses of inner_param: {:?}", args);
-            if args.contains(&Operand::Move(inner_param)) {
-                Some((loc, term))
-            } else {
-                None
-            }
+            args.contains(&Operand::Move(inner_param)).then_some((loc, term))
         }) else {
             debug!("no uses of inner_param found as a by-move call arg");
             return;
@@ -1497,7 +1491,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         assert!(root_place.projection.is_empty());
         let proper_span = self.body.local_decls[root_place.local].source_info.span;
 
-        let root_place_projection = self.infcx.tcx.intern_place_elems(root_place.projection);
+        let root_place_projection = self.infcx.tcx.mk_place_elems(root_place.projection);
 
         if self.access_place_error_reported.contains(&(
             Place { local: root_place.local, projection: root_place_projection },
@@ -1673,7 +1667,6 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 format!("`{}` would have to be valid for `{}`...", name, region_name),
             );
 
-            let fn_hir_id = self.mir_hir_id();
             err.span_label(
                 drop_span,
                 format!(
@@ -1681,19 +1674,12 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     name,
                     self.infcx
                         .tcx
-                        .hir()
-                        .opt_name(fn_hir_id)
+                        .opt_item_name(self.mir_def_id().to_def_id())
                         .map(|name| format!("function `{}`", name))
                         .unwrap_or_else(|| {
-                            match &self
-                                .infcx
-                                .tcx
-                                .typeck(self.mir_def_id())
-                                .node_type(fn_hir_id)
-                                .kind()
-                            {
-                                ty::Closure(..) => "enclosing closure",
-                                ty::Generator(..) => "enclosing generator",
+                            match &self.infcx.tcx.def_kind(self.mir_def_id()) {
+                                DefKind::Closure => "enclosing closure",
+                                DefKind::Generator => "enclosing generator",
                                 kind => bug!("expected closure or generator, found {:?}", kind),
                             }
                             .to_string()
@@ -1736,7 +1722,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 &self.local_names,
                 &mut err,
                 "",
-                None,
+                Some(borrow_span),
                 None,
             );
         }
@@ -2138,7 +2124,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
     ) -> DiagnosticBuilder<'cx, ErrorGuaranteed> {
         let tcx = self.infcx.tcx;
 
-        let (_, escapes_from) = tcx.article_and_description(self.mir_def_id().to_def_id());
+        let escapes_from = tcx.def_descr(self.mir_def_id().to_def_id());
 
         let mut err =
             borrowck_errors::borrowed_data_escapes_closure(tcx, escape_span, escapes_from);
@@ -2595,11 +2581,11 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             if is_closure {
                 None
             } else {
-                let ty = self.infcx.tcx.type_of(self.mir_def_id());
+                let ty = self.infcx.tcx.type_of(self.mir_def_id()).subst_identity();
                 match ty.kind() {
                     ty::FnDef(_, _) | ty::FnPtr(_) => self.annotate_fn_sig(
                         self.mir_def_id(),
-                        self.infcx.tcx.fn_sig(self.mir_def_id()),
+                        self.infcx.tcx.fn_sig(self.mir_def_id()).subst_identity(),
                     ),
                     _ => None,
                 }
@@ -2645,6 +2631,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                             operands,
                         ) = rvalue
                         {
+                            let def_id = def_id.expect_local();
                             for operand in operands {
                                 let (Operand::Copy(assigned_from) | Operand::Move(assigned_from)) = operand else {
                                     continue;
@@ -2667,7 +2654,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                                 // into a place then we should annotate the closure in
                                 // case it ends up being assigned into the return place.
                                 annotated_closure =
-                                    self.annotate_fn_sig(*def_id, substs.as_closure().sig());
+                                    self.annotate_fn_sig(def_id, substs.as_closure().sig());
                                 debug!(
                                     "annotate_argument_and_return_for_borrow: \
                                      annotated_closure={:?} assigned_from_local={:?} \
diff --git a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
index 209574709..19855075c 100644
--- a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
@@ -1,6 +1,8 @@
 //! Print diagnostics to explain why values are borrowed.
 
 use rustc_errors::{Applicability, Diagnostic};
+use rustc_hir as hir;
+use rustc_hir::intravisit::Visitor;
 use rustc_index::vec::IndexVec;
 use rustc_infer::infer::NllRegionVariableOrigin;
 use rustc_middle::mir::{
@@ -11,6 +13,7 @@ use rustc_middle::ty::adjustment::PointerCast;
 use rustc_middle::ty::{self, RegionVid, TyCtxt};
 use rustc_span::symbol::{kw, Symbol};
 use rustc_span::{sym, DesugaringKind, Span};
+use rustc_trait_selection::traits::error_reporting::FindExprBySpan;
 
 use crate::region_infer::{BlameConstraint, ExtraConstraintInfo};
 use crate::{
@@ -63,6 +66,36 @@ impl<'tcx> BorrowExplanation<'tcx> {
         borrow_span: Option<Span>,
         multiple_borrow_span: Option<(Span, Span)>,
     ) {
+        if let Some(span) = borrow_span {
+            let def_id = body.source.def_id();
+            if let Some(node) = tcx.hir().get_if_local(def_id)
+                && let Some(body_id) = node.body_id()
+            {
+                let body = tcx.hir().body(body_id);
+                let mut expr_finder = FindExprBySpan::new(span);
+                expr_finder.visit_expr(body.value);
+                if let Some(mut expr) = expr_finder.result {
+                    while let hir::ExprKind::AddrOf(_, _, inner)
+                        | hir::ExprKind::Unary(hir::UnOp::Deref, inner)
+                        | hir::ExprKind::Field(inner, _)
+                        | hir::ExprKind::MethodCall(_, inner, _, _)
+                        | hir::ExprKind::Index(inner, _) = &expr.kind
+                    {
+                        expr = inner;
+                    }
+                    if let hir::ExprKind::Path(hir::QPath::Resolved(None, p)) = expr.kind
+                        && let [hir::PathSegment { ident, args: None, .. }] = p.segments
+                        && let hir::def::Res::Local(hir_id) = p.res
+                        && let Some(hir::Node::Pat(pat)) = tcx.hir().find(hir_id)
+                    {
+                        err.span_label(
+                            pat.span,
+                            &format!("binding `{ident}` declared here"),
+                        );
+                    }
+                }
+            }
+        }
         match *self {
             BorrowExplanation::UsedLater(later_use_kind, var_or_use_span, path_span) => {
                 let message = match later_use_kind {
diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs
index 1b40b7143..a99fd594a 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mod.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs
@@ -115,11 +115,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     debug!("add_moved_or_invoked_closure_note: closure={:?}", closure);
                     if let ty::Closure(did, _) = self.body.local_decls[closure].ty.kind() {
                         let did = did.expect_local();
-                        let hir_id = self.infcx.tcx.hir().local_def_id_to_hir_id(did);
-
-                        if let Some((span, hir_place)) =
-                            self.infcx.tcx.typeck(did).closure_kind_origins().get(hir_id)
-                        {
+                        if let Some((span, hir_place)) = self.infcx.tcx.closure_kind_origin(did) {
                             diag.span_note(
                                 *span,
                                 &format!(
@@ -139,11 +135,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         if let Some(target) = target {
             if let ty::Closure(did, _) = self.body.local_decls[target].ty.kind() {
                 let did = did.expect_local();
-                let hir_id = self.infcx.tcx.hir().local_def_id_to_hir_id(did);
-
-                if let Some((span, hir_place)) =
-                    self.infcx.tcx.typeck(did).closure_kind_origins().get(hir_id)
-                {
+                if let Some((span, hir_place)) = self.infcx.tcx.closure_kind_origin(did) {
                     diag.span_note(
                         *span,
                         &format!(
@@ -373,14 +365,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     //
                     // We know the field exists so it's safe to call operator[] and `unwrap` here.
                     let def_id = def_id.expect_local();
-                    let var_id = self
-                        .infcx
-                        .tcx
-                        .typeck(def_id)
-                        .closure_min_captures_flattened(def_id)
-                        .nth(field.index())
-                        .unwrap()
-                        .get_root_variable();
+                    let var_id =
+                        self.infcx.tcx.closure_captures(def_id)[field.index()].get_root_variable();
 
                     Some(self.infcx.tcx.hir().name(var_id).to_string())
                 }
@@ -817,6 +803,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             && let AggregateKind::Closure(def_id, _) | AggregateKind::Generator(def_id, _, _) = **kind
         {
             debug!("move_spans: def_id={:?} places={:?}", def_id, places);
+            let def_id = def_id.expect_local();
             if let Some((args_span, generator_kind, capture_kind_span, path_span)) =
                 self.closure_span(def_id, moved_place, places)
             {
@@ -945,6 +932,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     box AggregateKind::Generator(def_id, _, _) => (def_id, true),
                     _ => continue,
                 };
+                let def_id = def_id.expect_local();
 
                 debug!(
                     "borrow_spans: def_id={:?} is_generator={:?} places={:?}",
@@ -985,7 +973,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         debug!("closure_span: hir_id={:?} expr={:?}", hir_id, expr);
         if let hir::ExprKind::Closure(&hir::Closure { body, fn_decl_span, .. }) = expr {
             for (captured_place, place) in
-                self.infcx.tcx.typeck(def_id).closure_min_captures_flattened(def_id).zip(places)
+                self.infcx.tcx.closure_captures(def_id).iter().zip(places)
             {
                 match place {
                     Operand::Copy(place) | Operand::Move(place)
@@ -1064,7 +1052,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                         );
                     }
                 }
-                CallKind::Normal { self_arg, desugaring, method_did } => {
+                CallKind::Normal { self_arg, desugaring, method_did, method_substs } => {
                     let self_arg = self_arg.unwrap();
                     let tcx = self.infcx.tcx;
                     if let Some((CallDesugaringKind::ForLoopIntoIter, _)) = desugaring {
@@ -1128,17 +1116,21 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                                 "{place_name} {partially_str}moved due to this method call{loop_message}",
                             ),
                         );
+
                         let infcx = tcx.infer_ctxt().build();
+                        // Erase and shadow everything that could be passed to the new infcx.
                         let ty = tcx.erase_regions(moved_place.ty(self.body, tcx).ty);
+                        let method_substs = tcx.erase_regions(method_substs);
+
                         if let ty::Adt(def, substs) = ty.kind()
                             && Some(def.did()) == tcx.lang_items().pin_type()
                             && let ty::Ref(_, _, hir::Mutability::Mut) = substs.type_at(0).kind()
-                            && let self_ty = infcx.replace_bound_vars_with_fresh_vars(
+                            && let self_ty = infcx.instantiate_binder_with_fresh_vars(
                                 fn_call_span,
                                 LateBoundRegionConversionTime::FnCall,
-                                tcx.fn_sig(method_did).input(0),
+                                tcx.fn_sig(method_did).subst(tcx, method_substs).input(0),
                             )
-                            && infcx.can_eq(self.param_env, ty, self_ty).is_ok()
+                            && infcx.can_eq(self.param_env, ty, self_ty)
                         {
                             err.span_suggestion_verbose(
                                 fn_call_span.shrink_to_lo(),
@@ -1176,13 +1168,13 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                         );
                     }
                     let parent_did = tcx.parent(method_did);
-                    let parent_self_ty = (tcx.def_kind(parent_did)
-                        == rustc_hir::def::DefKind::Impl)
-                        .then_some(parent_did)
-                        .and_then(|did| match tcx.type_of(did).kind() {
-                            ty::Adt(def, ..) => Some(def.did()),
-                            _ => None,
-                        });
+                    let parent_self_ty =
+                        matches!(tcx.def_kind(parent_did), rustc_hir::def::DefKind::Impl { .. })
+                            .then_some(parent_did)
+                            .and_then(|did| match tcx.type_of(did).subst_identity().kind() {
+                                ty::Adt(def, ..) => Some(def.did()),
+                                _ => None,
+                            });
                     let is_option_or_result = parent_self_ty.map_or(false, |def_id| {
                         matches!(tcx.get_diagnostic_name(def_id), Some(sym::Option | sym::Result))
                     });
diff --git a/compiler/rustc_borrowck/src/diagnostics/move_errors.rs b/compiler/rustc_borrowck/src/diagnostics/move_errors.rs
index 6db3c858a..5e4c7292e 100644
--- a/compiler/rustc_borrowck/src/diagnostics/move_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/move_errors.rs
@@ -448,7 +448,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                 };
                 self.note_type_does_not_implement_copy(err, &place_desc, place_ty, Some(span), "");
 
-                use_spans.args_span_label(err, format!("move out of {place_desc} occurs here"));
+                use_spans.args_span_label(err, format!("{place_desc} is moved here"));
             }
         }
     }
@@ -467,7 +467,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                 err.span_suggestion_verbose(
                     span.shrink_to_lo(),
                     "consider borrowing here",
-                    "&".to_string(),
+                    '&',
                     Applicability::MaybeIncorrect,
                 );
             }
diff --git a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
index 45b15c2c5..328ac880d 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
@@ -344,7 +344,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                     } else {
                         err.span_help(source_info.span, "try removing `&mut` here");
                     }
-                } else if decl.mutability == Mutability::Not {
+                } else if decl.mutability.is_not() {
                     if matches!(
                         decl.local_info,
                         Some(box LocalInfo::User(ClearCrossCrate::Set(BindingForm::ImplicitSelf(
@@ -385,7 +385,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                     err.span_suggestion_verbose(
                         local_decl.source_info.span.shrink_to_lo(),
                         "consider changing this to be mutable",
-                        "mut ".to_string(),
+                        "mut ",
                         Applicability::MachineApplicable,
                     );
                     let tcx = self.infcx.tcx;
@@ -606,12 +606,63 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                                 }
                             }
                             Some((false, err_label_span, message)) => {
-                                err.span_label(
-                                    err_label_span,
-                                    &format!(
-                                        "consider changing this binding's type to be: `{message}`"
-                                    ),
-                                );
+                                struct BindingFinder {
+                                    span: Span,
+                                    hir_id: Option<hir::HirId>,
+                                }
+
+                                impl<'tcx> Visitor<'tcx> for BindingFinder {
+                                    fn visit_stmt(&mut self, s: &'tcx hir::Stmt<'tcx>) {
+                                        if let hir::StmtKind::Local(local) = s.kind {
+                                            if local.pat.span == self.span {
+                                                self.hir_id = Some(local.hir_id);
+                                            }
+                                        }
+                                        hir::intravisit::walk_stmt(self, s);
+                                    }
+                                }
+                                let hir_map = self.infcx.tcx.hir();
+                                let def_id = self.body.source.def_id();
+                                let hir_id = hir_map.local_def_id_to_hir_id(def_id.expect_local());
+                                let node = hir_map.find(hir_id);
+                                let hir_id = if let Some(hir::Node::Item(item)) = node
+                                    && let hir::ItemKind::Fn(.., body_id) = item.kind
+                                {
+                                    let body = hir_map.body(body_id);
+                                    let mut v = BindingFinder {
+                                        span: err_label_span,
+                                        hir_id: None,
+                                    };
+                                    v.visit_body(body);
+                                    v.hir_id
+                                } else {
+                                    None
+                                };
+                                if let Some(hir_id) = hir_id
+                                    && let Some(hir::Node::Local(local)) = hir_map.find(hir_id)
+                                {
+                                    let (changing, span, sugg) = match local.ty {
+                                        Some(ty) => ("changing", ty.span, message),
+                                        None => (
+                                            "specifying",
+                                            local.pat.span.shrink_to_hi(),
+                                            format!(": {message}"),
+                                        ),
+                                    };
+                                    err.span_suggestion_verbose(
+                                        span,
+                                        &format!("consider {changing} this binding's type"),
+                                        sugg,
+                                        Applicability::HasPlaceholders,
+                                    );
+                                } else {
+                                    err.span_label(
+                                        err_label_span,
+                                        &format!(
+                                            "consider changing this binding's type to be: `{message}`"
+                                        ),
+                                    );
+                                }
                             }
                             None => {}
                         }
@@ -850,10 +901,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
         err: &mut Diagnostic,
     ) {
         let tables = tcx.typeck(closure_local_def_id);
-        let closure_hir_id = tcx.hir().local_def_id_to_hir_id(closure_local_def_id);
-        if let Some((span, closure_kind_origin)) =
-            &tables.closure_kind_origins().get(closure_hir_id)
-        {
+        if let Some((span, closure_kind_origin)) = tcx.closure_kind_origin(closure_local_def_id) {
             let reason = if let PlaceBase::Upvar(upvar_id) = closure_kind_origin.base {
                 let upvar = ty::place_to_string_for_capture(tcx, closure_kind_origin);
                 let root_hir_id = upvar_id.var_path.hir_id;
diff --git a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
index 187861ba1..ffe82b46c 100644
--- a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
@@ -415,7 +415,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
     /// fn foo<'a, 'b>(x: &'a u32) -> &'b u32 { x }
     /// ```
     ///
-    /// Here we would be invoked with `fr = 'a` and `outlived_fr = `'b`.
+    /// Here we would be invoked with `fr = 'a` and `outlived_fr = 'b`.
     pub(crate) fn report_region_error(
         &mut self,
         fr: RegionVid,
@@ -575,7 +575,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
 
         let mut output_ty = self.regioncx.universal_regions().unnormalized_output_ty;
         if let ty::Alias(ty::Opaque, ty::AliasTy { def_id, .. }) = *output_ty.kind() {
-            output_ty = self.infcx.tcx.type_of(def_id)
+            output_ty = self.infcx.tcx.type_of(def_id).subst_identity()
         };
 
         debug!("report_fnmut_error: output_ty={:?}", output_ty);
@@ -583,10 +583,12 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
         let err = FnMutError {
             span: *span,
             ty_err: match output_ty.kind() {
-                ty::Closure(_, _) => FnMutReturnTypeErr::ReturnClosure { span: *span },
                 ty::Generator(def, ..) if self.infcx.tcx.generator_is_async(*def) => {
                     FnMutReturnTypeErr::ReturnAsyncBlock { span: *span }
                 }
+                _ if output_ty.contains_closure() => {
+                    FnMutReturnTypeErr::ReturnClosure { span: *span }
+                }
                 _ => FnMutReturnTypeErr::ReturnRef { span: *span },
             },
         };
@@ -658,10 +660,8 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
             errci.outlived_fr,
         );
 
-        let (_, escapes_from) = self
-            .infcx
-            .tcx
-            .article_and_description(self.regioncx.universal_regions().defining_ty.def_id());
+        let escapes_from =
+            self.infcx.tcx.def_descr(self.regioncx.universal_regions().defining_ty.def_id());
 
         // Revert to the normal error in these cases.
         // Assignments aren't "escapes" in function items.
@@ -755,8 +755,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
             ..
         } = errci;
 
-        let (_, mir_def_name) =
-            self.infcx.tcx.article_and_description(self.mir_def_id().to_def_id());
+        let mir_def_name = self.infcx.tcx.def_descr(self.mir_def_id().to_def_id());
 
         let err = LifetimeOutliveErr { span: *span };
         let mut diag = self.infcx.tcx.sess.create_err(err);
@@ -813,17 +812,10 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
             if *outlived_f != ty::ReStatic {
                 return;
             }
+            let suitable_region = self.infcx.tcx.is_suitable_region(f);
+            let Some(suitable_region) = suitable_region else { return; };
 
-            let fn_returns = self
-                .infcx
-                .tcx
-                .is_suitable_region(f)
-                .map(|r| self.infcx.tcx.return_type_impl_or_dyn_traits(r.def_id))
-                .unwrap_or_default();
-
-            if fn_returns.is_empty() {
-                return;
-            }
+            let fn_returns = self.infcx.tcx.return_type_impl_or_dyn_traits(suitable_region.def_id);
 
             let param = if let Some(param) = find_param_with_region(self.infcx.tcx, f, outlived_f) {
                 param
@@ -839,15 +831,43 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
             };
             let captures = format!("captures data from {arg}");
 
-            return nice_region_error::suggest_new_region_bound(
-                self.infcx.tcx,
-                diag,
-                fn_returns,
-                lifetime.to_string(),
-                Some(arg),
-                captures,
-                Some((param.param_ty_span, param.param_ty.to_string())),
-                self.infcx.tcx.is_suitable_region(f).map(|r| r.def_id),
+            if !fn_returns.is_empty() {
+                nice_region_error::suggest_new_region_bound(
+                    self.infcx.tcx,
+                    diag,
+                    fn_returns,
+                    lifetime.to_string(),
+                    Some(arg),
+                    captures,
+                    Some((param.param_ty_span, param.param_ty.to_string())),
+                    Some(suitable_region.def_id),
+                );
+                return;
+            }
+
+            let Some((alias_tys, alias_span)) = self
+                .infcx
+                .tcx
+                .return_type_impl_or_dyn_traits_with_type_alias(suitable_region.def_id) else { return; };
+
+            // in case the return type of the method is a type alias
+            let mut spans_suggs: Vec<_> = Vec::new();
+            for alias_ty in alias_tys {
+                if alias_ty.span.desugaring_kind().is_some() {
+                    // Skip `async` desugaring `impl Future`.
+                    ()
+                }
+                if let TyKind::TraitObject(_, lt, _) = alias_ty.kind {
+                    spans_suggs.push((lt.ident.span.shrink_to_hi(), " + 'a".to_string()));
+                }
+            }
+            spans_suggs.push((alias_span.shrink_to_hi(), "<'a>".to_string()));
+            diag.multipart_suggestion_verbose(
+                &format!(
+                    "to declare that the trait object {captures}, you can add a lifetime parameter `'a` in the type alias"
+                ),
+                spans_suggs,
+                Applicability::MaybeIncorrect,
             );
         }
     }
@@ -873,7 +893,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
             debug!(?fn_did, ?substs);
 
             // Only suggest this on function calls, not closures
-            let ty = tcx.type_of(fn_did);
+            let ty = tcx.type_of(fn_did).subst_identity();
             debug!("ty: {:?}, ty.kind: {:?}", ty, ty.kind());
             if let ty::Closure(_, _) = ty.kind() {
                 return;
@@ -929,7 +949,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                     .push_span_label(*span, "this has an implicit `'static` lifetime requirement");
                 multi_span.push_span_label(
                     ident.span,
-                    "calling this method introduces the `impl`'s 'static` requirement",
+                    "calling this method introduces the `impl`'s `'static` requirement",
                 );
                 err.subdiagnostic(RequireStaticErr::UsedImpl { multi_span });
                 err.span_suggestion_verbose(
@@ -976,7 +996,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
     fn suggest_move_on_borrowing_closure(&self, diag: &mut Diagnostic) {
         let map = self.infcx.tcx.hir();
         let body_id = map.body_owned_by(self.mir_def_id());
-        let expr = &map.body(body_id).value;
+        let expr = &map.body(body_id).value.peel_blocks();
         let mut closure_span = None::<rustc_span::Span>;
         match expr.kind {
             hir::ExprKind::MethodCall(.., args, _) => {
@@ -991,20 +1011,14 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                     }
                 }
             }
-            hir::ExprKind::Block(blk, _) => {
-                if let Some(expr) = blk.expr {
-                    // only when the block is a closure
-                    if let hir::ExprKind::Closure(hir::Closure {
-                        capture_clause: hir::CaptureBy::Ref,
-                        body,
-                        ..
-                    }) = expr.kind
-                    {
-                        let body = map.body(*body);
-                        if !matches!(body.generator_kind, Some(hir::GeneratorKind::Async(..))) {
-                            closure_span = Some(expr.span.shrink_to_lo());
-                        }
-                    }
+            hir::ExprKind::Closure(hir::Closure {
+                capture_clause: hir::CaptureBy::Ref,
+                body,
+                ..
+            }) => {
+                let body = map.body(*body);
+                if !matches!(body.generator_kind, Some(hir::GeneratorKind::Async(..))) {
+                    closure_span = Some(expr.span.shrink_to_lo());
                 }
             }
             _ => {}
diff --git a/compiler/rustc_borrowck/src/diagnostics/region_name.rs b/compiler/rustc_borrowck/src/diagnostics/region_name.rs
index 9233287cf..f6881a2e5 100644
--- a/compiler/rustc_borrowck/src/diagnostics/region_name.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_name.rs
@@ -187,6 +187,12 @@ impl Display for RegionName {
     }
 }
 
+impl rustc_errors::IntoDiagnosticArg for RegionName {
+    fn into_diagnostic_arg(self) -> rustc_errors::DiagnosticArgValue<'static> {
+        self.to_string().into_diagnostic_arg()
+    }
+}
+
 impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
     pub(crate) fn mir_def_id(&self) -> hir::def_id::LocalDefId {
         self.body.source.def_id().expect_local()
@@ -274,17 +280,10 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
 
         debug!("give_region_a_name: error_region = {:?}", error_region);
         match *error_region {
-            ty::ReEarlyBound(ebr) => {
-                if ebr.has_name() {
-                    let span = tcx.hir().span_if_local(ebr.def_id).unwrap_or(DUMMY_SP);
-                    Some(RegionName {
-                        name: ebr.name,
-                        source: RegionNameSource::NamedEarlyBoundRegion(span),
-                    })
-                } else {
-                    None
-                }
-            }
+            ty::ReEarlyBound(ebr) => ebr.has_name().then(|| {
+                let span = tcx.hir().span_if_local(ebr.def_id).unwrap_or(DUMMY_SP);
+                RegionName { name: ebr.name, source: RegionNameSource::NamedEarlyBoundRegion(span) }
+            }),
 
             ty::ReStatic => {
                 Some(RegionName { name: kw::StaticLifetime, source: RegionNameSource::Static })
@@ -337,11 +336,11 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
                     let note = match closure_kind_ty.to_opt_closure_kind() {
                         Some(ty::ClosureKind::Fn) => {
                             "closure implements `Fn`, so references to captured variables \
-                                can't escape the closure"
+                             can't escape the closure"
                         }
                         Some(ty::ClosureKind::FnMut) => {
                             "closure implements `FnMut`, so references to captured variables \
-                                can't escape the closure"
+                             can't escape the closure"
                         }
                         Some(ty::ClosureKind::FnOnce) => {
                             bug!("BrEnv in a `FnOnce` closure");
@@ -358,7 +357,11 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
                 ty::BoundRegionKind::BrAnon(..) => None,
             },
 
-            ty::ReLateBound(..) | ty::ReVar(..) | ty::RePlaceholder(..) | ty::ReErased => None,
+            ty::ReLateBound(..)
+            | ty::ReVar(..)
+            | ty::RePlaceholder(..)
+            | ty::ReErased
+            | ty::ReError(_) => None,
         }
     }
 
@@ -842,12 +845,13 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
 
         let tcx = self.infcx.tcx;
         let region_parent = tcx.parent(region.def_id);
-        if tcx.def_kind(region_parent) != DefKind::Impl {
+        let DefKind::Impl { .. } = tcx.def_kind(region_parent) else {
             return None;
-        }
+        };
 
-        let found = tcx
-            .any_free_region_meets(&tcx.type_of(region_parent), |r| *r == ty::ReEarlyBound(region));
+        let found = tcx.any_free_region_meets(&tcx.type_of(region_parent).subst_identity(), |r| {
+            *r == ty::ReEarlyBound(region)
+        });
 
         Some(RegionName {
             name: self.synthesize_region_name(),