Merging upstream version 1.75.0+dfsg1.

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

29 files changed, 1266 insertions, 582 deletions

diff --git a/compiler/rustc_borrowck/Cargo.toml b/compiler/rustc_borrowck/Cargo.toml
index 56a9deb6a..636817a7c 100644
--- a/compiler/rustc_borrowck/Cargo.toml
+++ b/compiler/rustc_borrowck/Cargo.toml
@@ -3,19 +3,16 @@ name = "rustc_borrowck"
 version = "0.0.0"
 edition = "2021"
 
-[lib]
-
 [dependencies]
+# tidy-alphabetical-start
 either = "1.5.0"
 itertools = "0.10.1"
-tracing = "0.1"
 polonius-engine = "0.13.0"
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
 rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_errors = { path = "../rustc_errors" }
+rustc_fluent_macro = { path = "../rustc_fluent_macro" }
 rustc_graphviz = { path = "../rustc_graphviz" }
 rustc_hir = { path = "../rustc_hir" }
-rustc_fluent_macro = { path = "../rustc_fluent_macro" }
 rustc_index = { path = "../rustc_index" }
 rustc_infer = { path = "../rustc_infer" }
 rustc_lexer = { path = "../rustc_lexer" }
@@ -24,7 +21,10 @@ rustc_middle = { path = "../rustc_middle" }
 rustc_mir_dataflow = { path = "../rustc_mir_dataflow" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_session = { path = "../rustc_session" }
+rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
 rustc_traits = { path = "../rustc_traits" }
-rustc_span = { path = "../rustc_span" }
+smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
+tracing = "0.1"
+# tidy-alphabetical-end
diff --git a/compiler/rustc_borrowck/messages.ftl b/compiler/rustc_borrowck/messages.ftl
index 2c7b97afa..8c5a1d897 100644
--- a/compiler/rustc_borrowck/messages.ftl
+++ b/compiler/rustc_borrowck/messages.ftl
@@ -1,20 +1,20 @@
 borrowck_assign_due_to_use_closure =
     assignment occurs due to use in closure
 
-borrowck_assign_due_to_use_generator =
-    assign occurs due to use in generator
+borrowck_assign_due_to_use_coroutine =
+    assign occurs due to use in coroutine
 
 borrowck_assign_part_due_to_use_closure =
     assignment to part occurs due to use in closure
 
-borrowck_assign_part_due_to_use_generator =
-    assign to part occurs due to use in generator
+borrowck_assign_part_due_to_use_coroutine =
+    assign to part occurs due to use in coroutine
 
 borrowck_borrow_due_to_use_closure =
     borrow occurs due to use in closure
 
-borrowck_borrow_due_to_use_generator =
-    borrow occurs due to use in generator
+borrowck_borrow_due_to_use_coroutine =
+    borrow occurs due to use in coroutine
 
 borrowck_calling_operator_moves_lhs =
     calling this operator moves the left-hand side
@@ -142,11 +142,11 @@ borrowck_partial_var_move_by_use_in_closure =
         *[false] moved
     } due to use in closure
 
-borrowck_partial_var_move_by_use_in_generator =
+borrowck_partial_var_move_by_use_in_coroutine =
     variable {$is_partial ->
         [true] partially moved
         *[false] moved
-    } due to use in generator
+    } due to use in coroutine
 
 borrowck_returned_async_block_escaped =
     returns an `async` block that contains a reference to a captured variable, which then escapes the closure body
@@ -180,15 +180,15 @@ borrowck_ty_no_impl_copy =
 borrowck_use_due_to_use_closure =
     use occurs due to use in closure
 
-borrowck_use_due_to_use_generator =
-    use occurs due to use in generator
+borrowck_use_due_to_use_coroutine =
+    use occurs due to use in coroutine
 
 borrowck_used_impl_require_static =
     the used `impl` has a `'static` requirement
 
 borrowck_value_capture_here =
     value captured {$is_within ->
-        [true] here by generator
+        [true] here by coroutine
         *[false] here
     }
 
@@ -207,8 +207,8 @@ borrowck_value_moved_here =
 borrowck_var_borrow_by_use_in_closure =
     borrow occurs due to use in closure
 
-borrowck_var_borrow_by_use_in_generator =
-    borrow occurs due to use in generator
+borrowck_var_borrow_by_use_in_coroutine =
+    borrow occurs due to use in coroutine
 
 borrowck_var_borrow_by_use_place_in_closure =
     {$is_single_var ->
@@ -216,11 +216,11 @@ borrowck_var_borrow_by_use_place_in_closure =
         [false] borrows occur
     } due to use of {$place} in closure
 
-borrowck_var_borrow_by_use_place_in_generator =
+borrowck_var_borrow_by_use_place_in_coroutine =
     {$is_single_var ->
         *[true] borrow occurs
         [false] borrows occur
-    } due to use of {$place} in generator
+    } due to use of {$place} in coroutine
 
 borrowck_var_cannot_escape_closure =
     captured variable cannot escape `FnMut` closure body
@@ -234,8 +234,8 @@ borrowck_var_does_not_need_mut =
 borrowck_var_first_borrow_by_use_place_in_closure =
     first borrow occurs due to use of {$place} in closure
 
-borrowck_var_first_borrow_by_use_place_in_generator =
-    first borrow occurs due to use of {$place} in generator
+borrowck_var_first_borrow_by_use_place_in_coroutine =
+    first borrow occurs due to use of {$place} in coroutine
 
 borrowck_var_here_captured = variable captured here
 
@@ -244,8 +244,8 @@ borrowck_var_here_defined = variable defined here
 borrowck_var_move_by_use_in_closure =
     move occurs due to use in closure
 
-borrowck_var_move_by_use_in_generator =
-    move occurs due to use in generator
+borrowck_var_move_by_use_in_coroutine =
+    move occurs due to use in coroutine
 
 borrowck_var_mutable_borrow_by_use_place_in_closure =
     mutable borrow occurs due to use of {$place} in closure
@@ -253,5 +253,5 @@ borrowck_var_mutable_borrow_by_use_place_in_closure =
 borrowck_var_second_borrow_by_use_place_in_closure =
     second borrow occurs due to use of {$place} in closure
 
-borrowck_var_second_borrow_by_use_place_in_generator =
-    second borrow occurs due to use of {$place} in generator
+borrowck_var_second_borrow_by_use_place_in_coroutine =
+    second borrow occurs due to use of {$place} in coroutine
diff --git a/compiler/rustc_borrowck/src/borrowck_errors.rs b/compiler/rustc_borrowck/src/borrowck_errors.rs
index a2c7e767b..6731ef123 100644
--- a/compiler/rustc_borrowck/src/borrowck_errors.rs
+++ b/compiler/rustc_borrowck/src/borrowck_errors.rs
@@ -368,16 +368,17 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         err
     }
 
-    pub(crate) fn cannot_borrow_across_generator_yield(
+    pub(crate) fn cannot_borrow_across_coroutine_yield(
         &self,
         span: Span,
         yield_span: Span,
     ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> {
+        let coroutine_kind = self.body.coroutine.as_ref().unwrap().coroutine_kind;
         let mut err = struct_span_err!(
             self,
             span,
             E0626,
-            "borrow may still be in use when generator yields",
+            "borrow may still be in use when {coroutine_kind:#} yields",
         );
         err.span_label(yield_span, "possible yield occurs here");
         err
diff --git a/compiler/rustc_borrowck/src/dataflow.rs b/compiler/rustc_borrowck/src/dataflow.rs
index 4ac633c26..8676d2ba7 100644
--- a/compiler/rustc_borrowck/src/dataflow.rs
+++ b/compiler/rustc_borrowck/src/dataflow.rs
@@ -1,6 +1,7 @@
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 use rustc_data_structures::fx::FxIndexMap;
+use rustc_data_structures::graph::WithSuccessors;
 use rustc_index::bit_set::BitSet;
 use rustc_middle::mir::{
     self, BasicBlock, Body, CallReturnPlaces, Location, Place, TerminatorEdges,
@@ -222,6 +223,7 @@ impl<'tcx> OutOfScopePrecomputer<'_, 'tcx> {
     }
 }
 
+// This is `pub` because it's used by unstable external borrowck data users, see `consumers.rs`.
 pub fn calculate_borrows_out_of_scope_at_location<'tcx>(
     body: &Body<'tcx>,
     regioncx: &RegionInferenceContext<'tcx>,
@@ -238,15 +240,203 @@ pub fn calculate_borrows_out_of_scope_at_location<'tcx>(
     prec.borrows_out_of_scope_at_location
 }
 
+struct PoloniusOutOfScopePrecomputer<'a, 'tcx> {
+    visited: BitSet<mir::BasicBlock>,
+    visit_stack: Vec<mir::BasicBlock>,
+    body: &'a Body<'tcx>,
+    regioncx: &'a RegionInferenceContext<'tcx>,
+
+    loans_out_of_scope_at_location: FxIndexMap<Location, Vec<BorrowIndex>>,
+}
+
+impl<'a, 'tcx> PoloniusOutOfScopePrecomputer<'a, 'tcx> {
+    fn new(body: &'a Body<'tcx>, regioncx: &'a RegionInferenceContext<'tcx>) -> Self {
+        Self {
+            visited: BitSet::new_empty(body.basic_blocks.len()),
+            visit_stack: vec![],
+            body,
+            regioncx,
+            loans_out_of_scope_at_location: FxIndexMap::default(),
+        }
+    }
+}
+
+impl<'tcx> PoloniusOutOfScopePrecomputer<'_, 'tcx> {
+    /// Loans are in scope while they are live: whether they are contained within any live region.
+    /// In the location-insensitive analysis, a loan will be contained in a region if the issuing
+    /// region can reach it in the subset graph. So this is a reachability problem.
+    fn precompute_loans_out_of_scope(
+        &mut self,
+        loan_idx: BorrowIndex,
+        issuing_region: RegionVid,
+        loan_issued_at: Location,
+    ) {
+        let sccs = self.regioncx.constraint_sccs();
+        let universal_regions = self.regioncx.universal_regions();
+
+        // We first handle the cases where the loan doesn't go out of scope, depending on the issuing
+        // region's successors.
+        for successor in self.regioncx.region_graph().depth_first_search(issuing_region) {
+            // 1. Via applied member constraints
+            //
+            // The issuing region can flow into the choice regions, and they are either:
+            // - placeholders or free regions themselves,
+            // - or also transitively outlive a free region.
+            //
+            // That is to say, if there are applied member constraints here, the loan escapes the
+            // function and cannot go out of scope. We could early return here.
+            //
+            // For additional insurance via fuzzing and crater, we verify that the constraint's min
+            // choice indeed escapes the function. In the future, we could e.g. turn this check into
+            // a debug assert and early return as an optimization.
+            let scc = sccs.scc(successor);
+            for constraint in self.regioncx.applied_member_constraints(scc) {
+                if universal_regions.is_universal_region(constraint.min_choice) {
+                    return;
+                }
+            }
+
+            // 2. Via regions that are live at all points: placeholders and free regions.
+            //
+            // If the issuing region outlives such a region, its loan escapes the function and
+            // cannot go out of scope. We can early return.
+            if self.regioncx.is_region_live_at_all_points(successor) {
+                return;
+            }
+        }
+
+        let first_block = loan_issued_at.block;
+        let first_bb_data = &self.body.basic_blocks[first_block];
+
+        // The first block we visit is the one where the loan is issued, starting from the statement
+        // where the loan is issued: at `loan_issued_at`.
+        let first_lo = loan_issued_at.statement_index;
+        let first_hi = first_bb_data.statements.len();
+
+        if let Some(kill_location) =
+            self.loan_kill_location(loan_idx, loan_issued_at, first_block, first_lo, first_hi)
+        {
+            debug!("loan {:?} gets killed at {:?}", loan_idx, kill_location);
+            self.loans_out_of_scope_at_location.entry(kill_location).or_default().push(loan_idx);
+
+            // The loan dies within the first block, we're done and can early return.
+            return;
+        }
+
+        // The loan is not dead. Add successor BBs to the work list, if necessary.
+        for succ_bb in first_bb_data.terminator().successors() {
+            if self.visited.insert(succ_bb) {
+                self.visit_stack.push(succ_bb);
+            }
+        }
+
+        // We may end up visiting `first_block` again. This is not an issue: we know at this point
+        // that the loan is not killed in the `first_lo..=first_hi` range, so checking the
+        // `0..first_lo` range and the `0..first_hi` range gives the same result.
+        while let Some(block) = self.visit_stack.pop() {
+            let bb_data = &self.body[block];
+            let num_stmts = bb_data.statements.len();
+            if let Some(kill_location) =
+                self.loan_kill_location(loan_idx, loan_issued_at, block, 0, num_stmts)
+            {
+                debug!("loan {:?} gets killed at {:?}", loan_idx, kill_location);
+                self.loans_out_of_scope_at_location
+                    .entry(kill_location)
+                    .or_default()
+                    .push(loan_idx);
+
+                // The loan dies within this block, so we don't need to visit its successors.
+                continue;
+            }
+
+            // Add successor BBs to the work list, if necessary.
+            for succ_bb in bb_data.terminator().successors() {
+                if self.visited.insert(succ_bb) {
+                    self.visit_stack.push(succ_bb);
+                }
+            }
+        }
+
+        self.visited.clear();
+        assert!(self.visit_stack.is_empty(), "visit stack should be empty");
+    }
+
+    /// Returns the lowest statement in `start..=end`, where the loan goes out of scope, if any.
+    /// This is the statement where the issuing region can't reach any of the regions that are live
+    /// at this point.
+    fn loan_kill_location(
+        &self,
+        loan_idx: BorrowIndex,
+        loan_issued_at: Location,
+        block: BasicBlock,
+        start: usize,
+        end: usize,
+    ) -> Option<Location> {
+        for statement_index in start..=end {
+            let location = Location { block, statement_index };
+
+            // Check whether the issuing region can reach local regions that are live at this point:
+            // - a loan is always live at its issuing location because it can reach the issuing
+            // region, which is always live at this location.
+            if location == loan_issued_at {
+                continue;
+            }
+
+            // - the loan goes out of scope at `location` if it's not contained within any regions
+            // live at this point.
+            //
+            // FIXME: if the issuing region `i` can reach a live region `r` at point `p`, and `r` is
+            // live at point `q`, then it's guaranteed that `i` would reach `r` at point `q`.
+            // Reachability is location-insensitive, and we could take advantage of that, by jumping
+            // to a further point than just the next statement: we can jump to the furthest point
+            // within the block where `r` is live.
+            if self.regioncx.is_loan_live_at(loan_idx, location) {
+                continue;
+            }
+
+            // No live region is reachable from the issuing region: the loan is killed at this
+            // point.
+            return Some(location);
+        }
+
+        None
+    }
+}
+
 impl<'a, 'tcx> Borrows<'a, 'tcx> {
     pub fn new(
         tcx: TyCtxt<'tcx>,
         body: &'a Body<'tcx>,
-        nonlexical_regioncx: &'a RegionInferenceContext<'tcx>,
+        regioncx: &'a RegionInferenceContext<'tcx>,
         borrow_set: &'a BorrowSet<'tcx>,
     ) -> Self {
-        let borrows_out_of_scope_at_location =
-            calculate_borrows_out_of_scope_at_location(body, nonlexical_regioncx, borrow_set);
+        let mut borrows_out_of_scope_at_location =
+            calculate_borrows_out_of_scope_at_location(body, regioncx, borrow_set);
+
+        // The in-tree polonius analysis computes loans going out of scope using the set-of-loans
+        // model, and makes sure they're identical to the existing computation of the set-of-points
+        // model.
+        if tcx.sess.opts.unstable_opts.polonius.is_next_enabled() {
+            let mut polonius_prec = PoloniusOutOfScopePrecomputer::new(body, regioncx);
+            for (loan_idx, loan_data) in borrow_set.iter_enumerated() {
+                let issuing_region = loan_data.region;
+                let loan_issued_at = loan_data.reserve_location;
+
+                polonius_prec.precompute_loans_out_of_scope(
+                    loan_idx,
+                    issuing_region,
+                    loan_issued_at,
+                );
+            }
+
+            assert_eq!(
+                borrows_out_of_scope_at_location, polonius_prec.loans_out_of_scope_at_location,
+                "the loans out of scope must be the same as the borrows out of scope"
+            );
+
+            borrows_out_of_scope_at_location = polonius_prec.loans_out_of_scope_at_location;
+        }
+
         Borrows { tcx, body, borrow_set, borrows_out_of_scope_at_location }
     }
 
@@ -333,6 +523,13 @@ impl<'tcx> rustc_mir_dataflow::AnalysisDomain<'tcx> for Borrows<'_, 'tcx> {
     }
 }
 
+/// Forward dataflow computation of the set of borrows that are in scope at a particular location.
+/// - we gen the introduced loans
+/// - we kill loans on locals going out of (regular) scope
+/// - we kill the loans going out of their region's NLL scope: in NLL terms, the frontier where a
+///   region stops containing the CFG points reachable from the issuing location.
+/// - we also kill loans of conflicting places when overwriting a shared path: e.g. borrows of
+///   `a.b.c` when `a` is overwritten.
 impl<'tcx> rustc_mir_dataflow::GenKillAnalysis<'tcx> for Borrows<'_, 'tcx> {
     type Idx = BorrowIndex;
 
diff --git a/compiler/rustc_borrowck/src/def_use.rs b/compiler/rustc_borrowck/src/def_use.rs
index 95db93742..d0cf339e7 100644
--- a/compiler/rustc_borrowck/src/def_use.rs
+++ b/compiler/rustc_borrowck/src/def_use.rs
@@ -44,7 +44,7 @@ pub fn categorize(context: PlaceContext) -> Option<DefUse> {
         PlaceContext::MutatingUse(MutatingUseContext::Projection) |
 
         // Borrows only consider their local used at the point of the borrow.
-        // This won't affect the results since we use this analysis for generators
+        // This won't affect the results since we use this analysis for coroutines
         // and we only care about the result at suspension points. Borrows cannot
         // cross suspension points so this behavior is unproblematic.
         PlaceContext::MutatingUse(MutatingUseContext::Borrow) |
diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
index ee352e911..9a8f1c97e 100644
--- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -8,7 +8,7 @@ use rustc_errors::{
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::intravisit::{walk_block, walk_expr, Visitor};
-use rustc_hir::{AsyncGeneratorKind, GeneratorKind, LangItem};
+use rustc_hir::{CoroutineKind, CoroutineSource, LangItem};
 use rustc_infer::traits::ObligationCause;
 use rustc_middle::hir::nested_filter::OnlyBodies;
 use rustc_middle::mir::tcx::PlaceTy;
@@ -351,7 +351,9 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     }
                     // Check if we are in a situation of `ident @ ident` where we want to suggest
                     // `ref ident @ ref ident` or `ref ident @ Struct { ref ident }`.
-                    if let Some(subpat) = sub && self.pat.is_none() {
+                    if let Some(subpat) = sub
+                        && self.pat.is_none()
+                    {
                         self.visit_pat(subpat);
                         if self.pat.is_some() {
                             self.parent_pat = Some(p);
@@ -370,7 +372,9 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             let mut finder =
                 ExpressionFinder { expr_span: move_span, expr: None, pat: None, parent_pat: None };
             finder.visit_expr(expr);
-            if let Some(span) = span && let Some(expr) = finder.expr {
+            if let Some(span) = span
+                && let Some(expr) = finder.expr
+            {
                 for (_, expr) in hir.parent_iter(expr.hir_id) {
                     if let hir::Node::Expr(expr) = expr {
                         if expr.span.contains(span) {
@@ -425,10 +429,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                             Some(hir::intravisit::FnKind::Method(..)) => "method",
                             Some(hir::intravisit::FnKind::Closure) => "closure",
                         };
-                        span.push_span_label(
-                            ident.span,
-                            format!("in this {descr}"),
-                        );
+                        span.push_span_label(ident.span, format!("in this {descr}"));
                         err.span_note(
                             span,
                             format!(
@@ -441,15 +442,16 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     let ty = place.ty(self.body, self.infcx.tcx).ty;
                     if let hir::Node::Expr(parent_expr) = parent
                         && let hir::ExprKind::Call(call_expr, _) = parent_expr.kind
-                        && let hir::ExprKind::Path(
-                            hir::QPath::LangItem(LangItem::IntoIterIntoIter, _, _)
-                        ) = call_expr.kind
+                        && let hir::ExprKind::Path(hir::QPath::LangItem(
+                            LangItem::IntoIterIntoIter,
+                            _,
+                            _,
+                        )) = call_expr.kind
                     {
                         // Do not suggest `.clone()` in a `for` loop, we already suggest borrowing.
-                    } else if let UseSpans::FnSelfUse {
-                        kind: CallKind::Normal { .. },
-                        ..
-                    } = move_spans {
+                    } else if let UseSpans::FnSelfUse { kind: CallKind::Normal { .. }, .. } =
+                        move_spans
+                    {
                         // We already suggest cloning for these cases in `explain_captures`.
                     } else {
                         self.suggest_cloning(err, ty, expr, move_span);
@@ -602,10 +604,10 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     if self.sugg_span.is_some() {
                         return;
                     }
-                    if let hir::StmtKind::Local(hir::Local {
-                            span, ty, init: None, ..
-                        }) = &ex.kind && span.contains(self.decl_span) {
-                            self.sugg_span = ty.map_or(Some(self.decl_span), |ty| Some(ty.span));
+                    if let hir::StmtKind::Local(hir::Local { span, ty, init: None, .. }) = &ex.kind
+                        && span.contains(self.decl_span)
+                    {
+                        self.sugg_span = ty.map_or(Some(self.decl_span), |ty| Some(ty.span));
                     }
                     hir::intravisit::walk_stmt(self, ex);
                 }
@@ -743,19 +745,14 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 ".clone()".to_owned()
             };
         if let Some(clone_trait_def) = tcx.lang_items().clone_trait()
-            && self.infcx
-                .type_implements_trait(
-                    clone_trait_def,
-                    [ty],
-                    self.param_env,
-                )
+            && self
+                .infcx
+                .type_implements_trait(clone_trait_def, [ty], self.param_env)
                 .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()))
+                && [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 {
@@ -851,7 +848,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         move_spans.var_subdiag(None, &mut err, None, |kind, var_span| {
             use crate::session_diagnostics::CaptureVarCause::*;
             match kind {
-                Some(_) => MoveUseInGenerator { var_span },
+                Some(_) => MoveUseInCoroutine { var_span },
                 None => MoveUseInClosure { var_span },
             }
         });
@@ -897,7 +894,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             let desc_place = self.describe_any_place(place.as_ref());
             match kind {
                 Some(_) => {
-                    BorrowUsePlaceGenerator { place: desc_place, var_span, is_single_var: true }
+                    BorrowUsePlaceCoroutine { place: desc_place, var_span, is_single_var: true }
                 }
                 None => BorrowUsePlaceClosure { place: desc_place, var_span, is_single_var: true },
             }
@@ -929,8 +926,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let borrow_spans = self.borrow_spans(span, location);
         let span = borrow_spans.args_or_use();
 
-        let container_name = if issued_spans.for_generator() || borrow_spans.for_generator() {
-            "generator"
+        let container_name = if issued_spans.for_coroutine() || borrow_spans.for_coroutine() {
+            "coroutine"
         } else {
             "closure"
         };
@@ -1043,7 +1040,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                         |kind, var_span| {
                             use crate::session_diagnostics::CaptureVarCause::*;
                             match kind {
-                                Some(_) => BorrowUsePlaceGenerator {
+                                Some(_) => BorrowUsePlaceCoroutine {
                                     place: desc_place,
                                     var_span,
                                     is_single_var: true,
@@ -1127,7 +1124,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             borrow_spans.var_subdiag(None, &mut err, Some(gen_borrow_kind), |kind, var_span| {
                 use crate::session_diagnostics::CaptureVarCause::*;
                 match kind {
-                    Some(_) => BorrowUsePlaceGenerator {
+                    Some(_) => BorrowUsePlaceCoroutine {
                         place: desc_place,
                         var_span,
                         is_single_var: false,
@@ -1148,7 +1145,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     let borrow_place_desc = self.describe_any_place(borrow_place.as_ref());
                     match kind {
                         Some(_) => {
-                            FirstBorrowUsePlaceGenerator { place: borrow_place_desc, var_span }
+                            FirstBorrowUsePlaceCoroutine { place: borrow_place_desc, var_span }
                         }
                         None => FirstBorrowUsePlaceClosure { place: borrow_place_desc, var_span },
                     }
@@ -1162,7 +1159,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 |kind, var_span| {
                     use crate::session_diagnostics::CaptureVarCause::*;
                     match kind {
-                        Some(_) => SecondBorrowUsePlaceGenerator { place: desc_place, var_span },
+                        Some(_) => SecondBorrowUsePlaceCoroutine { place: desc_place, var_span },
                         None => SecondBorrowUsePlaceClosure { place: desc_place, var_span },
                     }
                 },
@@ -1328,42 +1325,160 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             issue_span: Span,
             expr_span: Span,
             body_expr: Option<&'hir hir::Expr<'hir>>,
-            loop_bind: Option<Symbol>,
+            loop_bind: Option<&'hir Ident>,
+            loop_span: Option<Span>,
+            head_span: Option<Span>,
+            pat_span: Option<Span>,
+            head: Option<&'hir hir::Expr<'hir>>,
         }
         impl<'hir> Visitor<'hir> for ExprFinder<'hir> {
             fn visit_expr(&mut self, ex: &'hir hir::Expr<'hir>) {
-                if let hir::ExprKind::Loop(hir::Block{ stmts: [stmt, ..], ..}, _, hir::LoopSource::ForLoop, _) = ex.kind &&
-                    let hir::StmtKind::Expr(hir::Expr{ kind: hir::ExprKind::Match(call, [_, bind, ..], _), ..}) = stmt.kind &&
-                    let hir::ExprKind::Call(path, _args) = call.kind &&
-                    let hir::ExprKind::Path(hir::QPath::LangItem(LangItem::IteratorNext, _, _, )) = path.kind &&
-                    let hir::PatKind::Struct(path, [field, ..], _) = bind.pat.kind &&
-                    let hir::QPath::LangItem(LangItem::OptionSome, _, _) = path &&
-                    let PatField { pat: hir::Pat{ kind: hir::PatKind::Binding(_, _, ident, ..), .. }, ..} = field &&
-                    self.issue_span.source_equal(call.span) {
-                        self.loop_bind = Some(ident.name);
+                // Try to find
+                // let result = match IntoIterator::into_iter(<head>) {
+                //     mut iter => {
+                //         [opt_ident]: loop {
+                //             match Iterator::next(&mut iter) {
+                //                 None => break,
+                //                 Some(<pat>) => <body>,
+                //             };
+                //         }
+                //     }
+                // };
+                // corresponding to the desugaring of a for loop `for <pat> in <head> { <body> }`.
+                if let hir::ExprKind::Call(path, [arg]) = ex.kind
+                    && let hir::ExprKind::Path(hir::QPath::LangItem(
+                        LangItem::IntoIterIntoIter,
+                        _,
+                        _,
+                    )) = path.kind
+                    && arg.span.contains(self.issue_span)
+                {
+                    // Find `IntoIterator::into_iter(<head>)`
+                    self.head = Some(arg);
+                }
+                if let hir::ExprKind::Loop(
+                    hir::Block { stmts: [stmt, ..], .. },
+                    _,
+                    hir::LoopSource::ForLoop,
+                    _,
+                ) = ex.kind
+                    && let hir::StmtKind::Expr(hir::Expr {
+                        kind: hir::ExprKind::Match(call, [_, bind, ..], _),
+                        span: head_span,
+                        ..
+                    }) = stmt.kind
+                    && let hir::ExprKind::Call(path, _args) = call.kind
+                    && let hir::ExprKind::Path(hir::QPath::LangItem(LangItem::IteratorNext, _, _)) =
+                        path.kind
+                    && let hir::PatKind::Struct(path, [field, ..], _) = bind.pat.kind
+                    && let hir::QPath::LangItem(LangItem::OptionSome, pat_span, _) = path
+                    && call.span.contains(self.issue_span)
+                {
+                    // Find `<pat>` and the span for the whole `for` loop.
+                    if let PatField {
+                        pat: hir::Pat { kind: hir::PatKind::Binding(_, _, ident, ..), .. },
+                        ..
+                    } = field
+                    {
+                        self.loop_bind = Some(ident);
                     }
+                    self.head_span = Some(*head_span);
+                    self.pat_span = Some(pat_span);
+                    self.loop_span = Some(stmt.span);
+                }
 
-                if let hir::ExprKind::MethodCall(body_call, _recv, ..) = ex.kind &&
-                    body_call.ident.name == sym::next && ex.span.source_equal(self.expr_span) {
-                        self.body_expr = Some(ex);
+                if let hir::ExprKind::MethodCall(body_call, recv, ..) = ex.kind
+                    && body_call.ident.name == sym::next
+                    && recv.span.source_equal(self.expr_span)
+                {
+                    self.body_expr = Some(ex);
                 }
 
                 hir::intravisit::walk_expr(self, ex);
             }
         }
-        let mut finder =
-            ExprFinder { expr_span: span, issue_span, loop_bind: None, body_expr: None };
+        let mut finder = ExprFinder {
+            expr_span: span,
+            issue_span,
+            loop_bind: None,
+            body_expr: None,
+            head_span: None,
+            loop_span: None,
+            pat_span: None,
+            head: None,
+        };
         finder.visit_expr(hir.body(body_id).value);
 
-        if let Some(loop_bind) = finder.loop_bind &&
-            let Some(body_expr) = finder.body_expr &&
-                let Some(def_id) = typeck_results.type_dependent_def_id(body_expr.hir_id) &&
-                let Some(trait_did) = tcx.trait_of_item(def_id) &&
-                tcx.is_diagnostic_item(sym::Iterator, trait_did) {
-                    err.note(format!(
-                        "a for loop advances the iterator for you, the result is stored in `{loop_bind}`."
+        if let Some(body_expr) = finder.body_expr
+            && let Some(loop_span) = finder.loop_span
+            && let Some(def_id) = typeck_results.type_dependent_def_id(body_expr.hir_id)
+            && let Some(trait_did) = tcx.trait_of_item(def_id)
+            && tcx.is_diagnostic_item(sym::Iterator, trait_did)
+        {
+            if let Some(loop_bind) = finder.loop_bind {
+                err.note(format!(
+                    "a for loop advances the iterator for you, the result is stored in `{}`",
+                    loop_bind.name,
+                ));
+            } else {
+                err.note(
+                    "a for loop advances the iterator for you, the result is stored in its pattern",
+                );
+            }
+            let msg = "if you want to call `next` on a iterator within the loop, consider using \
+                       `while let`";
+            if let Some(head) = finder.head
+                && let Some(pat_span) = finder.pat_span
+                && loop_span.contains(body_expr.span)
+                && loop_span.contains(head.span)
+            {
+                let sm = self.infcx.tcx.sess.source_map();
+
+                let mut sugg = vec![];
+                if let hir::ExprKind::Path(hir::QPath::Resolved(None, _)) = head.kind {
+                    // A bare path doesn't need a `let` assignment, it's already a simple
+                    // binding access.
+                    // As a new binding wasn't added, we don't need to modify the advancing call.
+                    sugg.push((loop_span.with_hi(pat_span.lo()), format!("while let Some(")));
+                    sugg.push((
+                        pat_span.shrink_to_hi().with_hi(head.span.lo()),
+                        ") = ".to_string(),
+                    ));
+                    sugg.push((head.span.shrink_to_hi(), ".next()".to_string()));
+                } else {
+                    // Needs a new a `let` binding.
+                    let indent = if let Some(indent) = sm.indentation_before(loop_span) {
+                        format!("\n{indent}")
+                    } else {
+                        " ".to_string()
+                    };
+                    let Ok(head_str) = sm.span_to_snippet(head.span) else {
+                        err.help(msg);
+                        return;
+                    };
+                    sugg.push((
+                        loop_span.with_hi(pat_span.lo()),
+                        format!("let iter = {head_str};{indent}while let Some("),
+                    ));
+                    sugg.push((
+                        pat_span.shrink_to_hi().with_hi(head.span.hi()),
+                        ") = iter.next()".to_string(),
                     ));
-                    err.help("if you want to call `next` on a iterator within the loop, consider using `while let`.");
+                    // As a new binding was added, we should change how the iterator is advanced to
+                    // use the newly introduced binding.
+                    if let hir::ExprKind::MethodCall(_, recv, ..) = body_expr.kind
+                        && let hir::ExprKind::Path(hir::QPath::Resolved(None, ..)) = recv.kind
+                    {
+                        // As we introduced a `let iter = <head>;`, we need to change where the
+                        // already borrowed value was accessed from `<recv>.next()` to
+                        // `iter.next()`.
+                        sugg.push((recv.span, "iter".to_string()));
+                    }
+                }
+                err.multipart_suggestion(msg, sugg, Applicability::MaybeIncorrect);
+            } else {
+                err.help(msg);
+            }
         }
     }
 
@@ -1459,7 +1574,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
 
         // Get closure's arguments
         let ty::Closure(_, args) = typeck_results.expr_ty(closure_expr).kind() else {
-            /* hir::Closure can be a generator too */
+            /* hir::Closure can be a coroutine too */
             return;
         };
         let sig = args.as_closure().sig();
@@ -1539,69 +1654,80 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             fn visit_expr(&mut self, e: &'hir hir::Expr<'hir>) {
                 if e.span.contains(self.capture_span) {
                     if let hir::ExprKind::Closure(&hir::Closure {
-                            movability: None,
-                            body,
-                            fn_arg_span,
-                            fn_decl: hir::FnDecl{ inputs, .. },
-                            ..
-                        }) = e.kind &&
-                        let Some(hir::Node::Expr(body )) = self.hir.find(body.hir_id) {
-                            self.suggest_arg = "this: &Self".to_string();
-                            if inputs.len() > 0 {
-                                self.suggest_arg.push_str(", ");
-                            }
-                            self.in_closure = true;
-                            self.closure_arg_span = fn_arg_span;
-                            self.visit_expr(body);
-                            self.in_closure = false;
+                        movability: None,
+                        body,
+                        fn_arg_span,
+                        fn_decl: hir::FnDecl { inputs, .. },
+                        ..
+                    }) = e.kind
+                        && let Some(hir::Node::Expr(body)) = self.hir.find(body.hir_id)
+                    {
+                        self.suggest_arg = "this: &Self".to_string();
+                        if inputs.len() > 0 {
+                            self.suggest_arg.push_str(", ");
+                        }
+                        self.in_closure = true;
+                        self.closure_arg_span = fn_arg_span;
+                        self.visit_expr(body);
+                        self.in_closure = false;
                     }
                 }
                 if let hir::Expr { kind: hir::ExprKind::Path(path), .. } = e {
-                    if let hir::QPath::Resolved(_, hir::Path { segments: [seg], ..}) = path &&
-                        seg.ident.name == kw::SelfLower && self.in_closure {
-                            self.closure_change_spans.push(e.span);
+                    if let hir::QPath::Resolved(_, hir::Path { segments: [seg], .. }) = path
+                        && seg.ident.name == kw::SelfLower
+                        && self.in_closure
+                    {
+                        self.closure_change_spans.push(e.span);
                     }
                 }
                 hir::intravisit::walk_expr(self, e);
             }
 
             fn visit_local(&mut self, local: &'hir hir::Local<'hir>) {
-                if let hir::Pat { kind: hir::PatKind::Binding(_, hir_id, _ident, _), .. } = local.pat &&
-                    let Some(init) = local.init
+                if let hir::Pat { kind: hir::PatKind::Binding(_, hir_id, _ident, _), .. } =
+                    local.pat
+                    && let Some(init) = local.init
                 {
-                    if let hir::Expr { kind: hir::ExprKind::Closure(&hir::Closure {
-                            movability: None,
-                            ..
-                        }), .. } = init &&
-                        init.span.contains(self.capture_span) {
-                            self.closure_local_id = Some(*hir_id);
+                    if let hir::Expr {
+                        kind: hir::ExprKind::Closure(&hir::Closure { movability: None, .. }),
+                        ..
+                    } = init
+                        && init.span.contains(self.capture_span)
+                    {
+                        self.closure_local_id = Some(*hir_id);
                     }
                 }
                 hir::intravisit::walk_local(self, local);
             }
 
             fn visit_stmt(&mut self, s: &'hir hir::Stmt<'hir>) {
-                if let hir::StmtKind::Semi(e) = s.kind &&
-                    let hir::ExprKind::Call(hir::Expr { kind: hir::ExprKind::Path(path), ..}, args) = e.kind &&
-                    let hir::QPath::Resolved(_, hir::Path { segments: [seg], ..}) = path &&
-                    let Res::Local(hir_id) = seg.res &&
-                        Some(hir_id) == self.closure_local_id {
-                        let (span, arg_str) = if args.len() > 0 {
-                            (args[0].span.shrink_to_lo(), "self, ".to_string())
-                        } else {
-                            let span = e.span.trim_start(seg.ident.span).unwrap_or(e.span);
-                            (span, "(self)".to_string())
-                        };
-                        self.closure_call_changes.push((span, arg_str));
+                if let hir::StmtKind::Semi(e) = s.kind
+                    && let hir::ExprKind::Call(
+                        hir::Expr { kind: hir::ExprKind::Path(path), .. },
+                        args,
+                    ) = e.kind
+                    && let hir::QPath::Resolved(_, hir::Path { segments: [seg], .. }) = path
+                    && let Res::Local(hir_id) = seg.res
+                    && Some(hir_id) == self.closure_local_id
+                {
+                    let (span, arg_str) = if args.len() > 0 {
+                        (args[0].span.shrink_to_lo(), "self, ".to_string())
+                    } else {
+                        let span = e.span.trim_start(seg.ident.span).unwrap_or(e.span);
+                        (span, "(self)".to_string())
+                    };
+                    self.closure_call_changes.push((span, arg_str));
                 }
                 hir::intravisit::walk_stmt(self, s);
             }
         }
 
-        if let Some(hir::Node::ImplItem(
-                    hir::ImplItem { kind: hir::ImplItemKind::Fn(_fn_sig, body_id), .. }
-                )) = hir.find(self.mir_hir_id()) &&
-            let Some(hir::Node::Expr(expr)) = hir.find(body_id.hir_id) {
+        if let Some(hir::Node::ImplItem(hir::ImplItem {
+            kind: hir::ImplItemKind::Fn(_fn_sig, body_id),
+            ..
+        })) = hir.find(self.mir_hir_id())
+            && let Some(hir::Node::Expr(expr)) = hir.find(body_id.hir_id)
+        {
             let mut finder = ExpressionFinder {
                 capture_span: *capture_kind_span,
                 closure_change_spans: vec![],
@@ -1822,7 +1948,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             (
                 Some(name),
                 BorrowExplanation::UsedLater(LaterUseKind::ClosureCapture, var_or_use_span, _),
-            ) if borrow_spans.for_generator() || borrow_spans.for_closure() => self
+            ) if borrow_spans.for_coroutine() || borrow_spans.for_closure() => self
                 .report_escaping_closure_capture(
                     borrow_spans,
                     borrow_span,
@@ -1847,7 +1973,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     span,
                     ..
                 },
-            ) if borrow_spans.for_generator() || borrow_spans.for_closure() => self
+            ) if borrow_spans.for_coroutine() || borrow_spans.for_closure() => self
                 .report_escaping_closure_capture(
                     borrow_spans,
                     borrow_span,
@@ -1950,8 +2076,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                         .unwrap_or_else(|| {
                             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),
+                                DefKind::Coroutine => "enclosing coroutine",
+                                kind => bug!("expected closure or coroutine, found {:?}", kind),
                             }
                             .to_string()
                         })
@@ -1985,7 +2111,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
 
             borrow_spans.args_subdiag(&mut err, |args_span| {
                 crate::session_diagnostics::CaptureArgLabel::Capture {
-                    is_within: borrow_spans.for_generator(),
+                    is_within: borrow_spans.for_coroutine(),
                     args_span,
                 }
             });
@@ -2136,6 +2262,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     current: usize,
                     found: usize,
                     prop_expr: Option<&'tcx hir::Expr<'tcx>>,
+                    call: Option<&'tcx hir::Expr<'tcx>>,
                 }
 
                 impl<'tcx> Visitor<'tcx> for NestedStatementVisitor<'tcx> {
@@ -2145,6 +2272,11 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                         self.current -= 1;
                     }
                     fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) {
+                        if let hir::ExprKind::MethodCall(_, rcvr, _, _) = expr.kind {
+                            if self.span == rcvr.span.source_callsite() {
+                                self.call = Some(expr);
+                            }
+                        }
                         if self.span == expr.span.source_callsite() {
                             self.found = self.current;
                             if self.prop_expr.is_none() {
@@ -2168,25 +2300,43 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                             current: 0,
                             found: 0,
                             prop_expr: None,
+                            call: None,
                         };
                         visitor.visit_stmt(stmt);
 
                         let typeck_results = self.infcx.tcx.typeck(self.mir_def_id());
-                        let expr_ty: Option<Ty<'_>> = visitor.prop_expr.map(|expr| typeck_results.expr_ty(expr).peel_refs());
+                        let expr_ty: Option<Ty<'_>> =
+                            visitor.prop_expr.map(|expr| typeck_results.expr_ty(expr).peel_refs());
 
-                        let is_format_arguments_item =
-                            if let Some(expr_ty) = expr_ty
-                               && let ty::Adt(adt, _) = expr_ty.kind() {
-                                    self.infcx.tcx.lang_items().get(LangItem::FormatArguments) == Some(adt.did())
-                               } else {
-                                   false
-                               };
+                        let is_format_arguments_item = if let Some(expr_ty) = expr_ty
+                            && let ty::Adt(adt, _) = expr_ty.kind()
+                        {
+                            self.infcx.tcx.lang_items().get(LangItem::FormatArguments)
+                                == Some(adt.did())
+                        } else {
+                            false
+                        };
 
                         if visitor.found == 0
                             && stmt.span.contains(proper_span)
                             && let Some(p) = sm.span_to_margin(stmt.span)
                             && let Ok(s) = sm.span_to_snippet(proper_span)
                         {
+                            if let Some(call) = visitor.call
+                                && let hir::ExprKind::MethodCall(path, _, [], _) = call.kind
+                                && path.ident.name == sym::iter
+                                && let Some(ty) = expr_ty
+                            {
+                                err.span_suggestion_verbose(
+                                    path.ident.span,
+                                    format!(
+                                        "consider consuming the `{ty}` when turning it into an \
+                                         `Iterator`",
+                                    ),
+                                    "into_iter".to_string(),
+                                    Applicability::MaybeIncorrect,
+                                );
+                            }
                             if !is_format_arguments_item {
                                 let addition = format!("let binding = {};\n{}", s, " ".repeat(p));
                                 err.multipart_suggestion_verbose(
@@ -2224,7 +2374,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
 
         borrow_spans.args_subdiag(&mut err, |args_span| {
             crate::session_diagnostics::CaptureArgLabel::Capture {
-                is_within: borrow_spans.for_generator(),
+                is_within: borrow_spans.for_coroutine(),
                 args_span,
             }
         });
@@ -2340,11 +2490,17 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
 
         let (sugg_span, suggestion) = match tcx.sess.source_map().span_to_snippet(args_span) {
             Ok(string) => {
-                if string.starts_with("async ") {
-                    let pos = args_span.lo() + BytePos(6);
-                    (args_span.with_lo(pos).with_hi(pos), "move ")
-                } else if string.starts_with("async|") {
-                    let pos = args_span.lo() + BytePos(5);
+                let coro_prefix = if string.starts_with("async") {
+                    // `async` is 5 chars long. Not using `.len()` to avoid the cast from `usize` to `u32`
+                    Some(5)
+                } else if string.starts_with("gen") {
+                    // `gen` is 3 chars long
+                    Some(3)
+                } else {
+                    None
+                };
+                if let Some(n) = coro_prefix {
+                    let pos = args_span.lo() + BytePos(n);
                     (args_span.with_lo(pos).with_hi(pos), " move")
                 } else {
                     (args_span.shrink_to_lo(), "move ")
@@ -2352,14 +2508,19 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             }
             Err(_) => (args_span, "move |<args>| <body>"),
         };
-        let kind = match use_span.generator_kind() {
-            Some(generator_kind) => match generator_kind {
-                GeneratorKind::Async(async_kind) => match async_kind {
-                    AsyncGeneratorKind::Block => "async block",
-                    AsyncGeneratorKind::Closure => "async closure",
+        let kind = match use_span.coroutine_kind() {
+            Some(coroutine_kind) => match coroutine_kind {
+                CoroutineKind::Gen(kind) => match kind {
+                    CoroutineSource::Block => "gen block",
+                    CoroutineSource::Closure => "gen closure",
+                    _ => bug!("gen block/closure expected, but gen function found."),
+                },
+                CoroutineKind::Async(async_kind) => match async_kind {
+                    CoroutineSource::Block => "async block",
+                    CoroutineSource::Closure => "async closure",
                     _ => bug!("async block/closure expected, but async function found."),
                 },
-                GeneratorKind::Gen => "generator",
+                CoroutineKind::Coroutine => "coroutine",
             },
             None => "closure",
         };
@@ -2388,7 +2549,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             }
             ConstraintCategory::CallArgument(_) => {
                 fr_name.highlight_region_name(&mut err);
-                if matches!(use_span.generator_kind(), Some(GeneratorKind::Async(_))) {
+                if matches!(use_span.coroutine_kind(), Some(CoroutineKind::Async(_))) {
                     err.note(
                         "async blocks are not executed immediately and must either take a \
                          reference or ownership of outside variables they use",
@@ -2482,9 +2643,10 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         /* Check if the mpi is initialized as an argument */
         let mut is_argument = false;
         for arg in self.body.args_iter() {
-            let path = self.move_data.rev_lookup.find_local(arg);
-            if mpis.contains(&path) {
-                is_argument = true;
+            if let Some(path) = self.move_data.rev_lookup.find_local(arg) {
+                if mpis.contains(&path) {
+                    is_argument = true;
+                }
             }
         }
 
@@ -2656,7 +2818,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 loan_spans.var_subdiag(None, &mut err, Some(loan.kind), |kind, var_span| {
                     use crate::session_diagnostics::CaptureVarCause::*;
                     match kind {
-                        Some(_) => BorrowUseInGenerator { var_span },
+                        Some(_) => BorrowUseInCoroutine { var_span },
                         None => BorrowUseInClosure { var_span },
                     }
                 });
@@ -2672,7 +2834,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         loan_spans.var_subdiag(None, &mut err, Some(loan.kind), |kind, var_span| {
             use crate::session_diagnostics::CaptureVarCause::*;
             match kind {
-                Some(_) => BorrowUseInGenerator { var_span },
+                Some(_) => BorrowUseInCoroutine { var_span },
                 None => BorrowUseInClosure { var_span },
             }
         });
diff --git a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
index c66a24473..8a930ca59 100644
--- a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
@@ -76,10 +76,10 @@ impl<'tcx> BorrowExplanation<'tcx> {
                 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
+                    | hir::ExprKind::Unary(hir::UnOp::Deref, inner)
+                    | hir::ExprKind::Field(inner, _)
+                    | hir::ExprKind::MethodCall(_, inner, _, _)
+                    | hir::ExprKind::Index(inner, _, _) = &expr.kind
                     {
                         expr = inner;
                     }
@@ -88,10 +88,7 @@ impl<'tcx> BorrowExplanation<'tcx> {
                         && 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"),
-                        );
+                        err.span_label(pat.span, format!("binding `{ident}` declared here"));
                     }
                 }
             }
@@ -185,7 +182,7 @@ impl<'tcx> BorrowExplanation<'tcx> {
                     // Otherwise, just report the whole type (and use
                     // the intentionally fuzzy phrase "destructor")
                     ty::Closure(..) => ("destructor", "closure".to_owned()),
-                    ty::Generator(..) => ("destructor", "generator".to_owned()),
+                    ty::Coroutine(..) => ("destructor", "coroutine".to_owned()),
 
                     _ => ("destructor", format!("type `{}`", local_decl.ty)),
                 };
@@ -419,7 +416,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 if self.local_names[local].is_some()
                     && let Some((WriteKind::StorageDeadOrDrop, place)) = kind_place
                     && let Some(borrowed_local) = place.as_local()
-                    && self.local_names[borrowed_local].is_some() && local != borrowed_local
+                    && self.local_names[borrowed_local].is_some()
+                    && local != borrowed_local
                 {
                     should_note_order = true;
                 }
diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs
index 8d4028de9..c4323fef9 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mod.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs
@@ -8,7 +8,7 @@ use itertools::Itertools;
 use rustc_errors::{Applicability, Diagnostic};
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, Namespace};
-use rustc_hir::GeneratorKind;
+use rustc_hir::CoroutineKind;
 use rustc_index::IndexSlice;
 use rustc_infer::infer::LateBoundRegionConversionTime;
 use rustc_middle::mir::tcx::PlaceTy;
@@ -46,6 +46,7 @@ mod mutability_errors;
 mod region_errors;
 
 pub(crate) use bound_region_errors::{ToUniverseInfo, UniverseInfo};
+pub(crate) use move_errors::{IllegalMoveOriginKind, MoveError};
 pub(crate) use mutability_errors::AccessKind;
 pub(crate) use outlives_suggestion::OutlivesSuggestionBuilder;
 pub(crate) use region_errors::{ErrorConstraintInfo, RegionErrorKind, RegionErrors};
@@ -369,7 +370,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 ty::Array(ty, _) | ty::Slice(ty) => {
                     self.describe_field_from_ty(ty, field, variant_index, including_tuple_field)
                 }
-                ty::Closure(def_id, _) | ty::Generator(def_id, _, _) => {
+                ty::Closure(def_id, _) | ty::Coroutine(def_id, _, _) => {
                     // We won't be borrowck'ing here if the closure came from another crate,
                     // so it's safe to call `expect_local`.
                     //
@@ -470,7 +471,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             }
         }
 
-        ty.print(printer).unwrap().into_buffer()
+        ty.print(&mut printer).unwrap();
+        printer.into_buffer()
     }
 
     /// Returns the name of the provided `Ty` (that must be a reference)'s region with a
@@ -492,7 +494,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             bug!("ty for annotation of borrow region is not a reference");
         };
 
-        region.print(printer).unwrap().into_buffer()
+        region.print(&mut printer).unwrap();
+        printer.into_buffer()
     }
 }
 
@@ -501,8 +504,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
 pub(super) enum UseSpans<'tcx> {
     /// The access is caused by capturing a variable for a closure.
     ClosureUse {
-        /// This is true if the captured variable was from a generator.
-        generator_kind: Option<GeneratorKind>,
+        /// This is true if the captured variable was from a coroutine.
+        coroutine_kind: Option<CoroutineKind>,
         /// The span of the args of the closure, including the `move` keyword if
         /// it's present.
         args_span: Span,
@@ -569,9 +572,9 @@ impl UseSpans<'_> {
         }
     }
 
-    pub(super) fn generator_kind(self) -> Option<GeneratorKind> {
+    pub(super) fn coroutine_kind(self) -> Option<CoroutineKind> {
         match self {
-            UseSpans::ClosureUse { generator_kind, .. } => generator_kind,
+            UseSpans::ClosureUse { coroutine_kind, .. } => coroutine_kind,
             _ => None,
         }
     }
@@ -596,14 +599,14 @@ impl UseSpans<'_> {
     ) {
         use crate::InitializationRequiringAction::*;
         use CaptureVarPathUseCause::*;
-        if let UseSpans::ClosureUse { generator_kind, path_span, .. } = self {
-            match generator_kind {
+        if let UseSpans::ClosureUse { coroutine_kind, path_span, .. } = self {
+            match coroutine_kind {
                 Some(_) => {
                     err.subdiagnostic(match action {
-                        Borrow => BorrowInGenerator { path_span },
-                        MatchOn | Use => UseInGenerator { path_span },
-                        Assignment => AssignInGenerator { path_span },
-                        PartialAssignment => AssignPartInGenerator { path_span },
+                        Borrow => BorrowInCoroutine { path_span },
+                        MatchOn | Use => UseInCoroutine { path_span },
+                        Assignment => AssignInCoroutine { path_span },
+                        PartialAssignment => AssignPartInCoroutine { path_span },
                     });
                 }
                 None => {
@@ -624,9 +627,9 @@ impl UseSpans<'_> {
         handler: Option<&rustc_errors::Handler>,
         err: &mut Diagnostic,
         kind: Option<rustc_middle::mir::BorrowKind>,
-        f: impl FnOnce(Option<GeneratorKind>, Span) -> CaptureVarCause,
+        f: impl FnOnce(Option<CoroutineKind>, Span) -> CaptureVarCause,
     ) {
-        if let UseSpans::ClosureUse { generator_kind, capture_kind_span, path_span, .. } = self {
+        if let UseSpans::ClosureUse { coroutine_kind, capture_kind_span, path_span, .. } = self {
             if capture_kind_span != path_span {
                 err.subdiagnostic(match kind {
                     Some(kd) => match kd {
@@ -642,7 +645,7 @@ impl UseSpans<'_> {
                     None => CaptureVarKind::Move { kind_span: capture_kind_span },
                 });
             };
-            let diag = f(generator_kind, path_span);
+            let diag = f(coroutine_kind, path_span);
             match handler {
                 Some(hd) => err.eager_subdiagnostic(hd, diag),
                 None => err.subdiagnostic(diag),
@@ -653,15 +656,15 @@ impl UseSpans<'_> {
     /// Returns `false` if this place is not used in a closure.
     pub(super) fn for_closure(&self) -> bool {
         match *self {
-            UseSpans::ClosureUse { generator_kind, .. } => generator_kind.is_none(),
+            UseSpans::ClosureUse { coroutine_kind, .. } => coroutine_kind.is_none(),
             _ => false,
         }
     }
 
-    /// Returns `false` if this place is not used in a generator.
-    pub(super) fn for_generator(&self) -> bool {
+    /// Returns `false` if this place is not used in a coroutine.
+    pub(super) fn for_coroutine(&self) -> bool {
         match *self {
-            UseSpans::ClosureUse { generator_kind, .. } => generator_kind.is_some(),
+            UseSpans::ClosureUse { coroutine_kind, .. } => coroutine_kind.is_some(),
             _ => false,
         }
     }
@@ -780,19 +783,15 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
 
         debug!("move_spans: moved_place={:?} location={:?} stmt={:?}", moved_place, location, stmt);
         if let StatementKind::Assign(box (_, Rvalue::Aggregate(kind, places))) = &stmt.kind
-            && let AggregateKind::Closure(def_id, _) | AggregateKind::Generator(def_id, _, _) = **kind
+            && let AggregateKind::Closure(def_id, _) | AggregateKind::Coroutine(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)) =
+            if let Some((args_span, coroutine_kind, capture_kind_span, path_span)) =
                 self.closure_span(def_id, moved_place, places)
             {
-                return ClosureUse {
-                    generator_kind,
-                    args_span,
-                    capture_kind_span,
-                    path_span,
-                };
+                return ClosureUse { coroutine_kind, args_span, capture_kind_span, path_span };
             }
         }
 
@@ -804,11 +803,11 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 | FakeReadCause::ForLet(Some(closure_def_id)) => {
                     debug!("move_spans: def_id={:?} place={:?}", closure_def_id, place);
                     let places = &[Operand::Move(place)];
-                    if let Some((args_span, generator_kind, capture_kind_span, path_span)) =
+                    if let Some((args_span, coroutine_kind, capture_kind_span, path_span)) =
                         self.closure_span(closure_def_id, moved_place, IndexSlice::from_raw(places))
                     {
                         return ClosureUse {
-                            generator_kind,
+                            coroutine_kind,
                             args_span,
                             capture_kind_span,
                             path_span,
@@ -918,21 +917,21 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
 
         for stmt in statements.chain(maybe_additional_statement) {
             if let StatementKind::Assign(box (_, Rvalue::Aggregate(kind, places))) = &stmt.kind {
-                let (&def_id, is_generator) = match kind {
+                let (&def_id, is_coroutine) = match kind {
                     box AggregateKind::Closure(def_id, _) => (def_id, false),
-                    box AggregateKind::Generator(def_id, _, _) => (def_id, true),
+                    box AggregateKind::Coroutine(def_id, _, _) => (def_id, true),
                     _ => continue,
                 };
                 let def_id = def_id.expect_local();
 
                 debug!(
-                    "borrow_spans: def_id={:?} is_generator={:?} places={:?}",
-                    def_id, is_generator, places
+                    "borrow_spans: def_id={:?} is_coroutine={:?} places={:?}",
+                    def_id, is_coroutine, places
                 );
-                if let Some((args_span, generator_kind, capture_kind_span, path_span)) =
+                if let Some((args_span, coroutine_kind, capture_kind_span, path_span)) =
                     self.closure_span(def_id, Place::from(target).as_ref(), places)
                 {
-                    return ClosureUse { generator_kind, args_span, capture_kind_span, path_span };
+                    return ClosureUse { coroutine_kind, args_span, capture_kind_span, path_span };
                 } else {
                     return OtherUse(use_span);
                 }
@@ -946,7 +945,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         OtherUse(use_span)
     }
 
-    /// Finds the spans of a captured place within a closure or generator.
+    /// Finds the spans of a captured place within a closure or coroutine.
     /// The first span is the location of the use resulting in the capture kind of the capture
     /// The second span is the location the use resulting in the captured path of the capture
     fn closure_span(
@@ -954,7 +953,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         def_id: LocalDefId,
         target_place: PlaceRef<'tcx>,
         places: &IndexSlice<FieldIdx, Operand<'tcx>>,
-    ) -> Option<(Span, Option<GeneratorKind>, Span, Span)> {
+    ) -> Option<(Span, Option<CoroutineKind>, Span, Span)> {
         debug!(
             "closure_span: def_id={:?} target_place={:?} places={:?}",
             def_id, target_place, places
@@ -972,11 +971,11 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     {
                         debug!("closure_span: found captured local {:?}", place);
                         let body = self.infcx.tcx.hir().body(body);
-                        let generator_kind = body.generator_kind();
+                        let coroutine_kind = body.coroutine_kind();
 
                         return Some((
                             fn_decl_span,
-                            generator_kind,
+                            coroutine_kind,
                             captured_place.get_capture_kind_span(self.infcx.tcx),
                             captured_place.get_path_span(self.infcx.tcx),
                         ));
@@ -1123,7 +1122,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                                 &self.infcx.tcx.sess.parse_sess.span_diagnostic,
                                 CaptureReasonSuggest::FreshReborrow {
                                     span: move_span.shrink_to_hi(),
-                                });
+                                },
+                            );
                         }
                         if let Some(clone_trait) = tcx.lang_items().clone_trait()
                             && let trait_ref = ty::TraitRef::new(tcx, clone_trait, [ty])
@@ -1191,7 +1191,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             // another message for the same span
             if !is_loop_message {
                 move_spans.var_subdiag(None, err, None, |kind, var_span| match kind {
-                    Some(_) => CaptureVarCause::PartialMoveUseInGenerator { var_span, is_partial },
+                    Some(_) => CaptureVarCause::PartialMoveUseInCoroutine { var_span, is_partial },
                     None => CaptureVarCause::PartialMoveUseInClosure { var_span, is_partial },
                 })
             }
diff --git a/compiler/rustc_borrowck/src/diagnostics/move_errors.rs b/compiler/rustc_borrowck/src/diagnostics/move_errors.rs
index e05c04e11..41d6b98d7 100644
--- a/compiler/rustc_borrowck/src/diagnostics/move_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/move_errors.rs
@@ -1,16 +1,50 @@
 use rustc_errors::{Applicability, Diagnostic, DiagnosticBuilder, ErrorGuaranteed};
 use rustc_middle::mir::*;
-use rustc_middle::ty;
-use rustc_mir_dataflow::move_paths::{
-    IllegalMoveOrigin, IllegalMoveOriginKind, LookupResult, MoveError, MovePathIndex,
-};
-use rustc_span::{BytePos, Span};
+use rustc_middle::ty::{self, Ty};
+use rustc_mir_dataflow::move_paths::{LookupResult, MovePathIndex};
+use rustc_span::{BytePos, ExpnKind, MacroKind, Span};
 
 use crate::diagnostics::CapturedMessageOpt;
 use crate::diagnostics::{DescribePlaceOpt, UseSpans};
 use crate::prefixes::PrefixSet;
 use crate::MirBorrowckCtxt;
 
+#[derive(Debug)]
+pub enum IllegalMoveOriginKind<'tcx> {
+    /// Illegal move due to attempt to move from behind a reference.
+    BorrowedContent {
+        /// The place the reference refers to: if erroneous code was trying to
+        /// move from `(*x).f` this will be `*x`.
+        target_place: Place<'tcx>,
+    },
+
+    /// Illegal move due to attempt to move from field of an ADT that
+    /// implements `Drop`. Rust maintains invariant that all `Drop`
+    /// ADT's remain fully-initialized so that user-defined destructor
+    /// can safely read from all of the ADT's fields.
+    InteriorOfTypeWithDestructor { container_ty: Ty<'tcx> },
+
+    /// Illegal move due to attempt to move out of a slice or array.
+    InteriorOfSliceOrArray { ty: Ty<'tcx>, is_index: bool },
+}
+
+#[derive(Debug)]
+pub(crate) struct MoveError<'tcx> {
+    place: Place<'tcx>,
+    location: Location,
+    kind: IllegalMoveOriginKind<'tcx>,
+}
+
+impl<'tcx> MoveError<'tcx> {
+    pub(crate) fn new(
+        place: Place<'tcx>,
+        location: Location,
+        kind: IllegalMoveOriginKind<'tcx>,
+    ) -> Self {
+        MoveError { place, location, kind }
+    }
+}
+
 // Often when desugaring a pattern match we may have many individual moves in
 // MIR that are all part of one operation from the user's point-of-view. For
 // example:
@@ -53,20 +87,18 @@ enum GroupedMoveError<'tcx> {
 }
 
 impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
-    pub(crate) fn report_move_errors(&mut self, move_errors: Vec<(Place<'tcx>, MoveError<'tcx>)>) {
-        let grouped_errors = self.group_move_errors(move_errors);
+    pub(crate) fn report_move_errors(&mut self) {
+        let grouped_errors = self.group_move_errors();
         for error in grouped_errors {
             self.report(error);
         }
     }
 
-    fn group_move_errors(
-        &self,
-        errors: Vec<(Place<'tcx>, MoveError<'tcx>)>,
-    ) -> Vec<GroupedMoveError<'tcx>> {
+    fn group_move_errors(&mut self) -> Vec<GroupedMoveError<'tcx>> {
         let mut grouped_errors = Vec::new();
-        for (original_path, error) in errors {
-            self.append_to_grouped_errors(&mut grouped_errors, original_path, error);
+        let errors = std::mem::take(&mut self.move_errors);
+        for error in errors {
+            self.append_to_grouped_errors(&mut grouped_errors, error);
         }
         grouped_errors
     }
@@ -74,66 +106,58 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
     fn append_to_grouped_errors(
         &self,
         grouped_errors: &mut Vec<GroupedMoveError<'tcx>>,
-        original_path: Place<'tcx>,
         error: MoveError<'tcx>,
     ) {
-        match error {
-            MoveError::UnionMove { .. } => {
-                unimplemented!("don't know how to report union move errors yet.")
-            }
-            MoveError::IllegalMove { cannot_move_out_of: IllegalMoveOrigin { location, kind } } => {
-                // Note: that the only time we assign a place isn't a temporary
-                // to a user variable is when initializing it.
-                // If that ever stops being the case, then the ever initialized
-                // flow could be used.
-                if let Some(StatementKind::Assign(box (
-                    place,
-                    Rvalue::Use(Operand::Move(move_from)),
-                ))) = self.body.basic_blocks[location.block]
-                    .statements
-                    .get(location.statement_index)
-                    .map(|stmt| &stmt.kind)
+        let MoveError { place: original_path, location, kind } = error;
+
+        // Note: that the only time we assign a place isn't a temporary
+        // to a user variable is when initializing it.
+        // If that ever stops being the case, then the ever initialized
+        // flow could be used.
+        if let Some(StatementKind::Assign(box (place, Rvalue::Use(Operand::Move(move_from))))) =
+            self.body.basic_blocks[location.block]
+                .statements
+                .get(location.statement_index)
+                .map(|stmt| &stmt.kind)
+        {
+            if let Some(local) = place.as_local() {
+                let local_decl = &self.body.local_decls[local];
+                // opt_match_place is the
+                // match_span is the span of the expression being matched on
+                // match *x.y { ... }        match_place is Some(*x.y)
+                //       ^^^^                match_span is the span of *x.y
+                //
+                // opt_match_place is None for let [mut] x = ... statements,
+                // whether or not the right-hand side is a place expression
+                if let LocalInfo::User(BindingForm::Var(VarBindingForm {
+                    opt_match_place: Some((opt_match_place, match_span)),
+                    binding_mode: _,
+                    opt_ty_info: _,
+                    pat_span: _,
+                })) = *local_decl.local_info()
                 {
-                    if let Some(local) = place.as_local() {
-                        let local_decl = &self.body.local_decls[local];
-                        // opt_match_place is the
-                        // match_span is the span of the expression being matched on
-                        // match *x.y { ... }        match_place is Some(*x.y)
-                        //       ^^^^                match_span is the span of *x.y
-                        //
-                        // opt_match_place is None for let [mut] x = ... statements,
-                        // whether or not the right-hand side is a place expression
-                        if let LocalInfo::User(BindingForm::Var(VarBindingForm {
-                            opt_match_place: Some((opt_match_place, match_span)),
-                            binding_mode: _,
-                            opt_ty_info: _,
-                            pat_span: _,
-                        })) = *local_decl.local_info()
-                        {
-                            let stmt_source_info = self.body.source_info(location);
-                            self.append_binding_error(
-                                grouped_errors,
-                                kind,
-                                original_path,
-                                *move_from,
-                                local,
-                                opt_match_place,
-                                match_span,
-                                stmt_source_info.span,
-                            );
-                            return;
-                        }
-                    }
+                    let stmt_source_info = self.body.source_info(location);
+                    self.append_binding_error(
+                        grouped_errors,
+                        kind,
+                        original_path,
+                        *move_from,
+                        local,
+                        opt_match_place,
+                        match_span,
+                        stmt_source_info.span,
+                    );
+                    return;
                 }
-
-                let move_spans = self.move_spans(original_path.as_ref(), location);
-                grouped_errors.push(GroupedMoveError::OtherIllegalMove {
-                    use_spans: move_spans,
-                    original_path,
-                    kind,
-                });
             }
         }
+
+        let move_spans = self.move_spans(original_path.as_ref(), location);
+        grouped_errors.push(GroupedMoveError::OtherIllegalMove {
+            use_spans: move_spans,
+            original_path,
+            kind,
+        });
     }
 
     fn append_binding_error(
@@ -464,6 +488,8 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                         args_span,
                     }
                 });
+
+                self.add_note_for_packed_struct_derive(err, original_path.local);
             }
         }
     }
@@ -570,4 +596,20 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
             );
         }
     }
+
+    /// Adds an explanatory note if the move error occurs in a derive macro
+    /// expansion of a packed struct.
+    /// Such errors happen because derive macro expansions shy away from taking
+    /// references to the struct's fields since doing so would be undefined behaviour
+    fn add_note_for_packed_struct_derive(&self, err: &mut Diagnostic, local: Local) {
+        let local_place: PlaceRef<'tcx> = local.into();
+        let local_ty = local_place.ty(self.body.local_decls(), self.infcx.tcx).ty.peel_refs();
+
+        if let Some(adt) = local_ty.ty_adt_def()
+            && adt.repr().packed()
+            && let ExpnKind::Macro(MacroKind::Derive, name) = self.body.span.ctxt().outer_expn_data().kind
+        {
+            err.note(format!("`#[derive({name})]` triggers a move because taking references to the fields of a packed struct is undefined behaviour"));
+        }
+    }
 }
diff --git a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
index 8ca57383e..dde46eef6 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
@@ -9,9 +9,8 @@ use rustc_middle::{
     hir::place::PlaceBase,
     mir::{self, BindingForm, Local, LocalDecl, LocalInfo, LocalKind, Location},
 };
-use rustc_span::source_map::DesugaringKind;
 use rustc_span::symbol::{kw, Symbol};
-use rustc_span::{sym, BytePos, Span};
+use rustc_span::{sym, BytePos, DesugaringKind, Span};
 use rustc_target::abi::FieldIdx;
 
 use crate::diagnostics::BorrowedContentSource;
@@ -62,7 +61,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                 local,
                 projection: [proj_base @ .., ProjectionElem::Field(upvar_index, _)],
             } => {
-                debug_assert!(is_closure_or_generator(
+                debug_assert!(is_closure_or_coroutine(
                     Place::ty_from(local, proj_base, self.body, self.infcx.tcx).ty
                 ));
 
@@ -122,7 +121,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                 {
                     item_msg = access_place_desc;
                     debug_assert!(self.body.local_decls[ty::CAPTURE_STRUCT_LOCAL].ty.is_ref());
-                    debug_assert!(is_closure_or_generator(
+                    debug_assert!(is_closure_or_coroutine(
                         the_place_err.ty(self.body, self.infcx.tcx).ty
                     ));
 
@@ -385,7 +384,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                 local,
                 projection: [proj_base @ .., ProjectionElem::Field(upvar_index, _)],
             } => {
-                debug_assert!(is_closure_or_generator(
+                debug_assert!(is_closure_or_coroutine(
                     Place::ty_from(local, proj_base, self.body, self.infcx.tcx).ty
                 ));
 
@@ -396,17 +395,16 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                 let upvar_hir_id = captured_place.get_root_variable();
 
                 if let Some(Node::Pat(pat)) = self.infcx.tcx.hir().find(upvar_hir_id)
-                    && let hir::PatKind::Binding(
-                        hir::BindingAnnotation::NONE,
-                        _,
-                        upvar_ident,
-                        _,
-                    ) = pat.kind
+                    && let hir::PatKind::Binding(hir::BindingAnnotation::NONE, _, upvar_ident, _) =
+                        pat.kind
                 {
                     if upvar_ident.name == kw::SelfLower {
                         for (_, node) in self.infcx.tcx.hir().parent_iter(upvar_hir_id) {
                             if let Some(fn_decl) = node.fn_decl() {
-                                if !matches!(fn_decl.implicit_self, hir::ImplicitSelfKind::ImmRef | hir::ImplicitSelfKind::MutRef) {
+                                if !matches!(
+                                    fn_decl.implicit_self,
+                                    hir::ImplicitSelfKind::ImmRef | hir::ImplicitSelfKind::MutRef
+                                ) {
                                     err.span_suggestion(
                                         upvar_ident.span,
                                         "consider changing this to be mutable",
@@ -573,7 +571,8 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                                 self.ty,
                             ),
                             vec![
-                                vec![ // val.insert(index, rv);
+                                vec![
+                                    // val.insert(index, rv);
                                     (
                                         val.span.shrink_to_hi().with_hi(index.span.lo()),
                                         ".insert(".to_string(),
@@ -584,7 +583,8 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                                     ),
                                     (rv.span.shrink_to_hi(), ")".to_string()),
                                 ],
-                                vec![ // val.get_mut(index).map(|v| { *v = rv; });
+                                vec![
+                                    // val.get_mut(index).map(|v| { *v = rv; });
                                     (
                                         val.span.shrink_to_hi().with_hi(index.span.lo()),
                                         ".get_mut(".to_string(),
@@ -593,12 +593,10 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                                         index.span.shrink_to_hi().with_hi(place.span.hi()),
                                         ").map(|val| { *val".to_string(),
                                     ),
-                                    (
-                                        rv.span.shrink_to_hi(),
-                                        "; })".to_string(),
-                                    ),
+                                    (rv.span.shrink_to_hi(), "; })".to_string()),
                                 ],
-                                vec![ // let x = val.entry(index).or_insert(rv);
+                                vec![
+                                    // let x = val.entry(index).or_insert(rv);
                                     (val.span.shrink_to_lo(), "let val = ".to_string()),
                                     (
                                         val.span.shrink_to_hi().with_hi(index.span.lo()),
@@ -747,10 +745,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
             && let Some(body_id) = hir_map.maybe_body_owned_by(local_def_id)
         {
             let body = hir_map.body(body_id);
-            let mut v = BindingFinder {
-                span: pat_span,
-                hir_id: None,
-            };
+            let mut v = BindingFinder { span: pat_span, hir_id: None };
             v.visit_body(body);
             v.hir_id
         } else {
@@ -766,7 +761,8 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                 pat: hir::Pat { kind: hir::PatKind::Ref(_, _), .. },
                 ..
             })) = hir_map.find(hir_id)
-            && let Ok(name) = self.infcx.tcx.sess.source_map().span_to_snippet(local_decl.source_info.span)
+            && let Ok(name) =
+                self.infcx.tcx.sess.source_map().span_to_snippet(local_decl.source_info.span)
         {
             err.span_suggestion(
                 pat_span,
@@ -879,12 +875,11 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
             // `span` corresponds to the expression being iterated, find the `for`-loop desugared
             // expression with that span in order to identify potential fixes when encountering a
             // read-only iterator that should be mutable.
-            let mut v = Finder {
-                span,
-                expr: None,
-            };
+            let mut v = Finder { span, expr: None };
             v.visit_block(block);
-            if let Some(expr) = v.expr && let Call(_, [expr]) = expr.kind {
+            if let Some(expr) = v.expr
+                && let Call(_, [expr]) = expr.kind
+            {
                 match expr.kind {
                     MethodCall(path_segment, _, _, span) => {
                         // We have `for _ in iter.read_only_iter()`, try to
@@ -1032,38 +1027,42 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
         let source = self.body.source;
         let hir = self.infcx.tcx.hir();
         if let InstanceDef::Item(def_id) = source.instance
-            && let Some(Node::Expr(hir::Expr { hir_id, kind, ..})) = hir.get_if_local(def_id)
-            && let ExprKind::Closure(closure) = kind && closure.movability == None
-            && let Some(Node::Expr(expr)) = hir.find_parent(*hir_id) {
-                let mut cur_expr = expr;
-                while let ExprKind::MethodCall(path_segment, recv, _, _) = cur_expr.kind {
-                    if path_segment.ident.name == sym::iter {
-                        // check `_ty` has `iter_mut` method
-                        let res = self
-                            .infcx
-                            .tcx
-                            .typeck(path_segment.hir_id.owner.def_id)
-                            .type_dependent_def_id(cur_expr.hir_id)
-                            .and_then(|def_id| self.infcx.tcx.impl_of_method(def_id))
-                            .map(|def_id| self.infcx.tcx.associated_items(def_id))
-                            .map(|assoc_items| {
-                                assoc_items.filter_by_name_unhygienic(sym::iter_mut).peekable()
-                            });
-
-                        if let Some(mut res) = res && res.peek().is_some() {
-                            err.span_suggestion_verbose(
-                                path_segment.ident.span,
-                                "you may want to use `iter_mut` here",
-                                "iter_mut",
-                                Applicability::MaybeIncorrect,
-                            );
-                        }
-                        break;
-                    } else {
-                        cur_expr = recv;
+            && let Some(Node::Expr(hir::Expr { hir_id, kind, .. })) = hir.get_if_local(def_id)
+            && let ExprKind::Closure(closure) = kind
+            && closure.movability == None
+            && let Some(Node::Expr(expr)) = hir.find_parent(*hir_id)
+        {
+            let mut cur_expr = expr;
+            while let ExprKind::MethodCall(path_segment, recv, _, _) = cur_expr.kind {
+                if path_segment.ident.name == sym::iter {
+                    // check `_ty` has `iter_mut` method
+                    let res = self
+                        .infcx
+                        .tcx
+                        .typeck(path_segment.hir_id.owner.def_id)
+                        .type_dependent_def_id(cur_expr.hir_id)
+                        .and_then(|def_id| self.infcx.tcx.impl_of_method(def_id))
+                        .map(|def_id| self.infcx.tcx.associated_items(def_id))
+                        .map(|assoc_items| {
+                            assoc_items.filter_by_name_unhygienic(sym::iter_mut).peekable()
+                        });
+
+                    if let Some(mut res) = res
+                        && res.peek().is_some()
+                    {
+                        err.span_suggestion_verbose(
+                            path_segment.ident.span,
+                            "you may want to use `iter_mut` here",
+                            "iter_mut",
+                            Applicability::MaybeIncorrect,
+                        );
                     }
+                    break;
+                } else {
+                    cur_expr = recv;
                 }
             }
+        }
     }
 
     fn suggest_make_local_mut(
@@ -1200,14 +1199,11 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                 }
                 let hir_map = self.infcx.tcx.hir();
                 let def_id = self.body.source.def_id();
-                let hir_id = if let Some(local_def_id) = def_id.as_local() &&
-                    let Some(body_id) = hir_map.maybe_body_owned_by(local_def_id)
+                let hir_id = if let Some(local_def_id) = def_id.as_local()
+                    && let Some(body_id) = hir_map.maybe_body_owned_by(local_def_id)
                 {
                     let body = hir_map.body(body_id);
-                    let mut v = BindingFinder {
-                        span: err_label_span,
-                        hir_id: None,
-                    };
+                    let mut v = BindingFinder { span: err_label_span, hir_id: None };
                     v.visit_body(body);
                     v.hir_id
                 } else {
@@ -1215,15 +1211,13 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                 };
 
                 if let Some(hir_id) = hir_id
-                && let Some(hir::Node::Local(local)) = hir_map.find(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}"),
-                        ),
+                        None => {
+                            ("specifying", local.pat.span.shrink_to_hi(), format!(": {message}"))
+                        }
                     };
                     err.span_suggestion_verbose(
                         span,
@@ -1234,9 +1228,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                 } else {
                     err.span_label(
                         err_label_span,
-                        format!(
-                            "consider changing this binding's type to be: `{message}`"
-                        ),
+                        format!("consider changing this binding's type to be: `{message}`"),
                     );
                 }
             }
@@ -1359,9 +1351,9 @@ fn suggest_ampmut<'tcx>(
         None => (false, decl_span),
     };
 
-    // if the binding already exists and is a reference with a explicit
+    // if the binding already exists and is a reference with an explicit
     // lifetime, then we can suggest adding ` mut`. this is special-cased from
-    // the path without a explicit lifetime.
+    // the path without an explicit lifetime.
     if let Ok(src) = tcx.sess.source_map().span_to_snippet(span)
         && src.starts_with("&'")
         // note that `&     'a T` is invalid so this is correct.
@@ -1380,16 +1372,12 @@ fn suggest_ampmut<'tcx>(
         let ty_mut = decl_ty.builtin_deref(true).unwrap();
         assert_eq!(ty_mut.mutbl, hir::Mutability::Not);
 
-        (
-            false,
-            span,
-            format!("{}mut {}", if decl_ty.is_ref() {"&"} else {"*"}, ty_mut.ty)
-        )
+        (false, span, format!("{}mut {}", if decl_ty.is_ref() { "&" } else { "*" }, ty_mut.ty))
     }
 }
 
-fn is_closure_or_generator(ty: Ty<'_>) -> bool {
-    ty.is_closure() || ty.is_generator()
+fn is_closure_or_coroutine(ty: Ty<'_>) -> bool {
+    ty.is_closure() || ty.is_coroutine()
 }
 
 /// Given a field that needs to be mutable, returns a span where the " mut " could go.
diff --git a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
index 27072a60f..a0a809123 100644
--- a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
@@ -580,7 +580,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
         let err = FnMutError {
             span: *span,
             ty_err: match output_ty.kind() {
-                ty::Generator(def, ..) if self.infcx.tcx.generator_is_async(*def) => {
+                ty::Coroutine(def, ..) if self.infcx.tcx.coroutine_is_async(*def) => {
                     FnMutReturnTypeErr::ReturnAsyncBlock { span: *span }
                 }
                 _ if output_ty.contains_closure() => {
@@ -1036,7 +1036,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                 ..
             }) => {
                 let body = map.body(*body);
-                if !matches!(body.generator_kind, Some(hir::GeneratorKind::Async(..))) {
+                if !matches!(body.coroutine_kind, Some(hir::CoroutineKind::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 55d581b3a..d38cfbc54 100644
--- a/compiler/rustc_borrowck/src/diagnostics/region_name.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_name.rs
@@ -41,7 +41,7 @@ pub(crate) enum RegionNameSource {
     AnonRegionFromUpvar(Span, Symbol),
     /// The region corresponding to the return type of a closure.
     AnonRegionFromOutput(RegionNameHighlight, &'static str),
-    /// The region from a type yielded by a generator.
+    /// The region from a type yielded by a coroutine.
     AnonRegionFromYieldTy(Span, String),
     /// An anonymous region from an async fn.
     AnonRegionFromAsyncFn(Span),
@@ -322,7 +322,7 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
                     let def_ty = self.regioncx.universal_regions().defining_ty;
 
                     let DefiningTy::Closure(_, args) = def_ty else {
-                        // Can't have BrEnv in functions, constants or generators.
+                        // Can't have BrEnv in functions, constants or coroutines.
                         bug!("BrEnv outside of closure.");
                     };
                     let hir::ExprKind::Closure(&hir::Closure { fn_decl_span, .. }) =
@@ -680,16 +680,16 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
                     }
                     hir::FnRetTy::Return(hir_ty) => (fn_decl.output.span(), Some(hir_ty)),
                 };
-                let mir_description = match hir.body(body).generator_kind {
-                    Some(hir::GeneratorKind::Async(gen)) => match gen {
-                        hir::AsyncGeneratorKind::Block => " of async block",
-                        hir::AsyncGeneratorKind::Closure => " of async closure",
-                        hir::AsyncGeneratorKind::Fn => {
+                let mir_description = match hir.body(body).coroutine_kind {
+                    Some(hir::CoroutineKind::Async(gen)) => match gen {
+                        hir::CoroutineSource::Block => " of async block",
+                        hir::CoroutineSource::Closure => " of async closure",
+                        hir::CoroutineSource::Fn => {
                             let parent_item =
                                 hir.get_by_def_id(hir.get_parent_item(mir_hir_id).def_id);
                             let output = &parent_item
                                 .fn_decl()
-                                .expect("generator lowered from async fn should be in fn")
+                                .expect("coroutine lowered from async fn should be in fn")
                                 .output;
                             span = output.span();
                             if let hir::FnRetTy::Return(ret) = output {
@@ -698,7 +698,21 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
                             " of async function"
                         }
                     },
-                    Some(hir::GeneratorKind::Gen) => " of generator",
+                    Some(hir::CoroutineKind::Gen(gen)) => match gen {
+                        hir::CoroutineSource::Block => " of gen block",
+                        hir::CoroutineSource::Closure => " of gen closure",
+                        hir::CoroutineSource::Fn => {
+                            let parent_item =
+                                hir.get_by_def_id(hir.get_parent_item(mir_hir_id).def_id);
+                            let output = &parent_item
+                                .fn_decl()
+                                .expect("coroutine lowered from gen fn should be in fn")
+                                .output;
+                            span = output.span();
+                            " of gen function"
+                        }
+                    },
+                    Some(hir::CoroutineKind::Coroutine) => " of coroutine",
                     None => " of closure",
                 };
                 (span, mir_description, hir_ty)
@@ -793,7 +807,7 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
         &self,
         fr: RegionVid,
     ) -> Option<RegionName> {
-        // Note: generators from `async fn` yield `()`, so we don't have to
+        // Note: coroutines from `async fn` yield `()`, so we don't have to
         // worry about them here.
         let yield_ty = self.regioncx.universal_regions().yield_ty?;
         debug!("give_name_if_anonymous_region_appears_in_yield_ty: yield_ty = {:?}", yield_ty);
@@ -942,9 +956,7 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
                         ty::ClauseKind::Projection(data) if data.projection_ty.self_ty() == ty => {}
                         _ => return false,
                     }
-                    tcx.any_free_region_meets(pred, |r| {
-                        *r == ty::ReEarlyBound(region)
-                    })
+                    tcx.any_free_region_meets(pred, |r| *r == ty::ReEarlyBound(region))
                 })
             } else {
                 false
diff --git a/compiler/rustc_borrowck/src/diagnostics/var_name.rs b/compiler/rustc_borrowck/src/diagnostics/var_name.rs
index 8832d345d..3a104c524 100644
--- a/compiler/rustc_borrowck/src/diagnostics/var_name.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/var_name.rs
@@ -6,8 +6,8 @@ use crate::Upvar;
 use rustc_index::IndexSlice;
 use rustc_middle::mir::{Body, Local};
 use rustc_middle::ty::{RegionVid, TyCtxt};
-use rustc_span::source_map::Span;
 use rustc_span::symbol::Symbol;
+use rustc_span::Span;
 
 impl<'tcx> RegionInferenceContext<'tcx> {
     pub(crate) fn get_var_name_and_span_for_region(
diff --git a/compiler/rustc_borrowck/src/facts.rs b/compiler/rustc_borrowck/src/facts.rs
index 9916ebca3..c54e70704 100644
--- a/compiler/rustc_borrowck/src/facts.rs
+++ b/compiler/rustc_borrowck/src/facts.rs
@@ -41,7 +41,8 @@ pub(crate) trait AllFactsExt {
 impl AllFactsExt for AllFacts {
     /// Return
     fn enabled(tcx: TyCtxt<'_>) -> bool {
-        tcx.sess.opts.unstable_opts.nll_facts || tcx.sess.opts.unstable_opts.polonius
+        tcx.sess.opts.unstable_opts.nll_facts
+            || tcx.sess.opts.unstable_opts.polonius.is_legacy_enabled()
     }
 
     fn write_to_dir(
diff --git a/compiler/rustc_borrowck/src/invalidation.rs b/compiler/rustc_borrowck/src/invalidation.rs
index 2faf1a529..ec6d7b74e 100644
--- a/compiler/rustc_borrowck/src/invalidation.rs
+++ b/compiler/rustc_borrowck/src/invalidation.rs
@@ -161,7 +161,7 @@ impl<'cx, 'tcx> Visitor<'tcx> for InvalidationGenerator<'cx, 'tcx> {
             }
             TerminatorKind::UnwindResume
             | TerminatorKind::Return
-            | TerminatorKind::GeneratorDrop => {
+            | TerminatorKind::CoroutineDrop => {
                 // Invalidate all borrows of local places
                 let borrow_set = self.borrow_set;
                 let start = self.location_table.start_index(location);
diff --git a/compiler/rustc_borrowck/src/lib.rs b/compiler/rustc_borrowck/src/lib.rs
index 1d17df8b7..5787ea13e 100644
--- a/compiler/rustc_borrowck/src/lib.rs
+++ b/compiler/rustc_borrowck/src/lib.rs
@@ -1,5 +1,8 @@
 //! This query borrow-checks the MIR to (further) ensure it is not broken.
 
+#![allow(internal_features)]
+#![cfg_attr(not(bootstrap), feature(rustdoc_internals))]
+#![cfg_attr(not(bootstrap), doc(rust_logo))]
 #![feature(associated_type_bounds)]
 #![feature(box_patterns)]
 #![feature(let_chains)]
@@ -11,7 +14,6 @@
 #![feature(trusted_step)]
 #![feature(try_blocks)]
 #![recursion_limit = "256"]
-#![allow(internal_features)]
 
 #[macro_use]
 extern crate rustc_middle;
@@ -29,13 +31,8 @@ use rustc_index::{IndexSlice, IndexVec};
 use rustc_infer::infer::{
     InferCtxt, NllRegionVariableOrigin, RegionVariableOrigin, TyCtxtInferExt,
 };
-use rustc_middle::mir::{
-    traversal, Body, ClearCrossCrate, Local, Location, MutBorrowKind, Mutability,
-    NonDivergingIntrinsic, Operand, Place, PlaceElem, PlaceRef, VarDebugInfoContents,
-};
-use rustc_middle::mir::{AggregateKind, BasicBlock, BorrowCheckResult, BorrowKind};
-use rustc_middle::mir::{InlineAsmOperand, Terminator, TerminatorKind};
-use rustc_middle::mir::{ProjectionElem, Promoted, Rvalue, Statement, StatementKind};
+use rustc_middle::mir::tcx::PlaceTy;
+use rustc_middle::mir::*;
 use rustc_middle::query::Providers;
 use rustc_middle::traits::DefiningAnchor;
 use rustc_middle::ty::{self, CapturedPlace, ParamEnv, RegionVid, TyCtxt};
@@ -53,13 +50,13 @@ use rustc_mir_dataflow::impls::{
     EverInitializedPlaces, MaybeInitializedPlaces, MaybeUninitializedPlaces,
 };
 use rustc_mir_dataflow::move_paths::{InitIndex, MoveOutIndex, MovePathIndex};
-use rustc_mir_dataflow::move_paths::{InitLocation, LookupResult, MoveData, MoveError};
+use rustc_mir_dataflow::move_paths::{InitLocation, LookupResult, MoveData};
 use rustc_mir_dataflow::Analysis;
 use rustc_mir_dataflow::MoveDataParamEnv;
 
 use crate::session_diagnostics::VarNeedNotMut;
 
-use self::diagnostics::{AccessKind, RegionName};
+use self::diagnostics::{AccessKind, IllegalMoveOriginKind, MoveError, RegionName};
 use self::location::LocationTable;
 use self::prefixes::PrefixSet;
 use consumers::{BodyWithBorrowckFacts, ConsumerOptions};
@@ -173,7 +170,9 @@ fn do_mir_borrowck<'tcx>(
     for var_debug_info in &input_body.var_debug_info {
         if let VarDebugInfoContents::Place(place) = var_debug_info.value {
             if let Some(local) = place.as_local() {
-                if let Some(prev_name) = local_names[local] && var_debug_info.name != prev_name {
+                if let Some(prev_name) = local_names[local]
+                    && var_debug_info.name != prev_name
+                {
                     span_bug!(
                         var_debug_info.source_info.span,
                         "local {:?} has many names (`{}` vs `{}`)",
@@ -220,14 +219,10 @@ fn do_mir_borrowck<'tcx>(
     let location_table_owned = LocationTable::new(body);
     let location_table = &location_table_owned;
 
-    let (move_data, move_errors): (MoveData<'tcx>, Vec<(Place<'tcx>, MoveError<'tcx>)>) =
-        match MoveData::gather_moves(&body, tcx, param_env) {
-            Ok(move_data) => (move_data, Vec::new()),
-            Err((move_data, move_errors)) => (move_data, move_errors),
-        };
-    let promoted_errors = promoted
+    let move_data = MoveData::gather_moves(&body, tcx, param_env, |_| true);
+    let promoted_move_data = promoted
         .iter_enumerated()
-        .map(|(idx, body)| (idx, MoveData::gather_moves(&body, tcx, param_env)));
+        .map(|(idx, body)| (idx, MoveData::gather_moves(&body, tcx, param_env, |_| true)));
 
     let mdpe = MoveDataParamEnv { move_data, param_env };
 
@@ -298,47 +293,60 @@ fn do_mir_borrowck<'tcx>(
         .pass_name("borrowck")
         .iterate_to_fixpoint();
 
-    let movable_generator =
-        // The first argument is the generator type passed by value
+    let movable_coroutine =
+        // The first argument is the coroutine type passed by value
         if let Some(local) = body.local_decls.raw.get(1)
         // Get the interior types and args which typeck computed
-        && let ty::Generator(_, _, hir::Movability::Static) = local.ty.kind()
+        && let ty::Coroutine(_, _, hir::Movability::Static) = local.ty.kind()
     {
         false
     } else {
         true
     };
 
-    for (idx, move_data_results) in promoted_errors {
-        let promoted_body = &promoted[idx];
+    for (idx, move_data) in promoted_move_data {
+        use rustc_middle::mir::visit::Visitor;
 
-        if let Err((move_data, move_errors)) = move_data_results {
-            let mut promoted_mbcx = MirBorrowckCtxt {
-                infcx: &infcx,
-                param_env,
-                body: promoted_body,
-                move_data: &move_data,
-                location_table, // no need to create a real one for the promoted, it is not used
-                movable_generator,
-                fn_self_span_reported: Default::default(),
-                locals_are_invalidated_at_exit,
-                access_place_error_reported: Default::default(),
-                reservation_error_reported: Default::default(),
-                uninitialized_error_reported: Default::default(),
-                regioncx: regioncx.clone(),
-                used_mut: Default::default(),
-                used_mut_upvars: SmallVec::new(),
-                borrow_set: Rc::clone(&borrow_set),
-                upvars: Vec::new(),
-                local_names: IndexVec::from_elem(None, &promoted_body.local_decls),
-                region_names: RefCell::default(),
-                next_region_name: RefCell::new(1),
-                polonius_output: None,
-                errors,
-            };
-            promoted_mbcx.report_move_errors(move_errors);
-            errors = promoted_mbcx.errors;
+        let promoted_body = &promoted[idx];
+        let mut promoted_mbcx = MirBorrowckCtxt {
+            infcx: &infcx,
+            param_env,
+            body: promoted_body,
+            move_data: &move_data,
+            location_table, // no need to create a real one for the promoted, it is not used
+            movable_coroutine,
+            fn_self_span_reported: Default::default(),
+            locals_are_invalidated_at_exit,
+            access_place_error_reported: Default::default(),
+            reservation_error_reported: Default::default(),
+            uninitialized_error_reported: Default::default(),
+            regioncx: regioncx.clone(),
+            used_mut: Default::default(),
+            used_mut_upvars: SmallVec::new(),
+            borrow_set: Rc::clone(&borrow_set),
+            upvars: Vec::new(),
+            local_names: IndexVec::from_elem(None, &promoted_body.local_decls),
+            region_names: RefCell::default(),
+            next_region_name: RefCell::new(1),
+            polonius_output: None,
+            move_errors: Vec::new(),
+            errors,
         };
+        MoveVisitor { ctxt: &mut promoted_mbcx }.visit_body(promoted_body);
+        promoted_mbcx.report_move_errors();
+        errors = promoted_mbcx.errors;
+
+        struct MoveVisitor<'a, 'cx, 'tcx> {
+            ctxt: &'a mut MirBorrowckCtxt<'cx, 'tcx>,
+        }
+
+        impl<'tcx> Visitor<'tcx> for MoveVisitor<'_, '_, 'tcx> {
+            fn visit_operand(&mut self, operand: &Operand<'tcx>, location: Location) {
+                if let Operand::Move(place) = operand {
+                    self.ctxt.check_movable_place(location, *place);
+                }
+            }
+        }
     }
 
     let mut mbcx = MirBorrowckCtxt {
@@ -347,7 +355,7 @@ fn do_mir_borrowck<'tcx>(
         body,
         move_data: &mdpe.move_data,
         location_table,
-        movable_generator,
+        movable_coroutine,
         locals_are_invalidated_at_exit,
         fn_self_span_reported: Default::default(),
         access_place_error_reported: Default::default(),
@@ -362,6 +370,7 @@ fn do_mir_borrowck<'tcx>(
         region_names: RefCell::default(),
         next_region_name: RefCell::new(1),
         polonius_output,
+        move_errors: Vec::new(),
         errors,
     };
 
@@ -374,8 +383,6 @@ fn do_mir_borrowck<'tcx>(
         borrows: flow_borrows,
     };
 
-    mbcx.report_move_errors(move_errors);
-
     rustc_mir_dataflow::visit_results(
         body,
         traversal::reverse_postorder(body).map(|(bb, _)| bb),
@@ -383,6 +390,8 @@ fn do_mir_borrowck<'tcx>(
         &mut mbcx,
     );
 
+    mbcx.report_move_errors();
+
     // For each non-user used mutable variable, check if it's been assigned from
     // a user-declared local. If so, then put that local into the used_mut set.
     // Note that this set is expected to be small - only upvars from closures
@@ -532,7 +541,7 @@ struct MirBorrowckCtxt<'cx, 'tcx> {
     /// when MIR borrowck begins.
     location_table: &'cx LocationTable,
 
-    movable_generator: bool,
+    movable_coroutine: bool,
     /// This keeps track of whether local variables are free-ed when the function
     /// exits even without a `StorageDead`, which appears to be the case for
     /// constants.
@@ -591,6 +600,7 @@ struct MirBorrowckCtxt<'cx, 'tcx> {
     polonius_output: Option<Rc<PoloniusOutput>>,
 
     errors: error::BorrowckErrors<'tcx>,
+    move_errors: Vec<MoveError<'tcx>>,
 }
 
 // Check that:
@@ -721,7 +731,6 @@ impl<'cx, 'tcx, R> rustc_mir_dataflow::ResultsVisitor<'cx, 'tcx, R> for MirBorro
             }
             TerminatorKind::Assert { cond, expected: _, msg, target: _, unwind: _ } => {
                 self.consume_operand(loc, (cond, span), flow_state);
-                use rustc_middle::mir::AssertKind;
                 if let AssertKind::BoundsCheck { len, index } = &**msg {
                     self.consume_operand(loc, (len, span), flow_state);
                     self.consume_operand(loc, (index, span), flow_state);
@@ -774,7 +783,7 @@ impl<'cx, 'tcx, R> rustc_mir_dataflow::ResultsVisitor<'cx, 'tcx, R> for MirBorro
             | TerminatorKind::Unreachable
             | TerminatorKind::UnwindResume
             | TerminatorKind::Return
-            | TerminatorKind::GeneratorDrop
+            | TerminatorKind::CoroutineDrop
             | TerminatorKind::FalseEdge { real_target: _, imaginary_target: _ }
             | TerminatorKind::FalseUnwind { real_target: _, unwind: _ } => {
                 // no data used, thus irrelevant to borrowck
@@ -793,7 +802,7 @@ impl<'cx, 'tcx, R> rustc_mir_dataflow::ResultsVisitor<'cx, 'tcx, R> for MirBorro
 
         match term.kind {
             TerminatorKind::Yield { value: _, resume: _, resume_arg: _, drop: _ } => {
-                if self.movable_generator {
+                if self.movable_coroutine {
                     // Look for any active borrows to locals
                     let borrow_set = self.borrow_set.clone();
                     for i in flow_state.borrows.iter() {
@@ -805,7 +814,7 @@ impl<'cx, 'tcx, R> rustc_mir_dataflow::ResultsVisitor<'cx, 'tcx, R> for MirBorro
 
             TerminatorKind::UnwindResume
             | TerminatorKind::Return
-            | TerminatorKind::GeneratorDrop => {
+            | TerminatorKind::CoroutineDrop => {
                 // Returning from the function implicitly kills storage for all locals and statics.
                 // Often, the storage will already have been killed by an explicit
                 // StorageDead, but we don't always emit those (notably on unwind paths),
@@ -1322,7 +1331,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 // moved into the closure and subsequently used by the closure,
                 // in order to populate our used_mut set.
                 match **aggregate_kind {
-                    AggregateKind::Closure(def_id, _) | AggregateKind::Generator(def_id, _, _) => {
+                    AggregateKind::Closure(def_id, _) | AggregateKind::Coroutine(def_id, _, _) => {
                         let def_id = def_id.expect_local();
                         let BorrowCheckResult { used_mut_upvars, .. } =
                             self.infcx.tcx.mir_borrowck(def_id);
@@ -1405,7 +1414,9 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                         // As such we have to search for the local that this
                         // capture comes from and mark it as being used as mut.
 
-                        let temp_mpi = self.move_data.rev_lookup.find_local(local);
+                        let Some(temp_mpi) = self.move_data.rev_lookup.find_local(local) else {
+                            bug!("temporary should be tracked");
+                        };
                         let init = if let [init_index] = *self.move_data.init_path_map[temp_mpi] {
                             &self.move_data.inits[init_index]
                         } else {
@@ -1465,6 +1476,9 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 );
             }
             Operand::Move(place) => {
+                // Check if moving from this place makes sense.
+                self.check_movable_place(location, place);
+
                 // move of place: check if this is move of already borrowed path
                 self.access_place(
                     location,
@@ -1545,12 +1559,12 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
     }
 
     /// Reports an error if this is a borrow of local data.
-    /// This is called for all Yield expressions on movable generators
+    /// This is called for all Yield expressions on movable coroutines
     fn check_for_local_borrow(&mut self, borrow: &BorrowData<'tcx>, yield_span: Span) {
         debug!("check_for_local_borrow({:?})", borrow);
 
         if borrow_of_local_data(borrow.borrowed_place) {
-            let err = self.cannot_borrow_across_generator_yield(
+            let err = self.cannot_borrow_across_coroutine_yield(
                 self.retrieve_borrow_spans(borrow).var_or_use(),
                 yield_span,
             );
@@ -1586,6 +1600,131 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         }
     }
 
+    fn check_movable_place(&mut self, location: Location, place: Place<'tcx>) {
+        use IllegalMoveOriginKind::*;
+
+        let body = self.body;
+        let tcx = self.infcx.tcx;
+        let mut place_ty = PlaceTy::from_ty(body.local_decls[place.local].ty);
+        for (place_ref, elem) in place.iter_projections() {
+            match elem {
+                ProjectionElem::Deref => match place_ty.ty.kind() {
+                    ty::Ref(..) | ty::RawPtr(..) => {
+                        self.move_errors.push(MoveError::new(
+                            place,
+                            location,
+                            BorrowedContent {
+                                target_place: place_ref.project_deeper(&[elem], tcx),
+                            },
+                        ));
+                        return;
+                    }
+                    ty::Adt(adt, _) => {
+                        if !adt.is_box() {
+                            bug!("Adt should be a box type when Place is deref");
+                        }
+                    }
+                    ty::Bool
+                    | ty::Char
+                    | ty::Int(_)
+                    | ty::Uint(_)
+                    | ty::Float(_)
+                    | ty::Foreign(_)
+                    | ty::Str
+                    | ty::Array(_, _)
+                    | ty::Slice(_)
+                    | ty::FnDef(_, _)
+                    | ty::FnPtr(_)
+                    | ty::Dynamic(_, _, _)
+                    | ty::Closure(_, _)
+                    | ty::Coroutine(_, _, _)
+                    | ty::CoroutineWitness(..)
+                    | ty::Never
+                    | ty::Tuple(_)
+                    | ty::Alias(_, _)
+                    | ty::Param(_)
+                    | ty::Bound(_, _)
+                    | ty::Infer(_)
+                    | ty::Error(_)
+                    | ty::Placeholder(_) => {
+                        bug!("When Place is Deref it's type shouldn't be {place_ty:#?}")
+                    }
+                },
+                ProjectionElem::Field(_, _) => match place_ty.ty.kind() {
+                    ty::Adt(adt, _) => {
+                        if adt.has_dtor(tcx) {
+                            self.move_errors.push(MoveError::new(
+                                place,
+                                location,
+                                InteriorOfTypeWithDestructor { container_ty: place_ty.ty },
+                            ));
+                            return;
+                        }
+                    }
+                    ty::Closure(_, _) | ty::Coroutine(_, _, _) | ty::Tuple(_) => (),
+                    ty::Bool
+                    | ty::Char
+                    | ty::Int(_)
+                    | ty::Uint(_)
+                    | ty::Float(_)
+                    | ty::Foreign(_)
+                    | ty::Str
+                    | ty::Array(_, _)
+                    | ty::Slice(_)
+                    | ty::RawPtr(_)
+                    | ty::Ref(_, _, _)
+                    | ty::FnDef(_, _)
+                    | ty::FnPtr(_)
+                    | ty::Dynamic(_, _, _)
+                    | ty::CoroutineWitness(..)
+                    | ty::Never
+                    | ty::Alias(_, _)
+                    | ty::Param(_)
+                    | ty::Bound(_, _)
+                    | ty::Infer(_)
+                    | ty::Error(_)
+                    | ty::Placeholder(_) => bug!(
+                        "When Place contains ProjectionElem::Field it's type shouldn't be {place_ty:#?}"
+                    ),
+                },
+                ProjectionElem::ConstantIndex { .. } | ProjectionElem::Subslice { .. } => {
+                    match place_ty.ty.kind() {
+                        ty::Slice(_) => {
+                            self.move_errors.push(MoveError::new(
+                                place,
+                                location,
+                                InteriorOfSliceOrArray { ty: place_ty.ty, is_index: false },
+                            ));
+                            return;
+                        }
+                        ty::Array(_, _) => (),
+                        _ => bug!("Unexpected type {:#?}", place_ty.ty),
+                    }
+                }
+                ProjectionElem::Index(_) => match place_ty.ty.kind() {
+                    ty::Array(..) | ty::Slice(..) => {
+                        self.move_errors.push(MoveError::new(
+                            place,
+                            location,
+                            InteriorOfSliceOrArray { ty: place_ty.ty, is_index: true },
+                        ));
+                        return;
+                    }
+                    _ => bug!("Unexpected type {place_ty:#?}"),
+                },
+                // `OpaqueCast`: only transmutes the type, so no moves there.
+                // `Downcast`  : only changes information about a `Place` without moving.
+                // `Subtype`   : only transmutes the type, so no moves.
+                // So it's safe to skip these.
+                ProjectionElem::OpaqueCast(_)
+                | ProjectionElem::Subtype(_)
+                | ProjectionElem::Downcast(_, _) => (),
+            }
+
+            place_ty = place_ty.projection_ty(tcx, elem);
+        }
+    }
+
     fn check_if_full_path_is_moved(
         &mut self,
         location: Location,
@@ -1967,7 +2106,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             Reservation(WriteKind::MutableBorrow(BorrowKind::Mut { kind: mut_borrow_kind }))
             | Write(WriteKind::MutableBorrow(BorrowKind::Mut { kind: mut_borrow_kind })) => {
                 let is_local_mutation_allowed = match mut_borrow_kind {
-                    // `ClosureCapture` is used for mutable variable with a immutable binding.
+                    // `ClosureCapture` is used for mutable variable with an immutable binding.
                     // This is only behaviour difference between `ClosureCapture` and mutable borrows.
                     MutBorrowKind::ClosureCapture => LocalMutationIsAllowed::Yes,
                     MutBorrowKind::Default | MutBorrowKind::TwoPhaseBorrow => {
@@ -2070,7 +2209,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         local: Local,
         flow_state: &Flows<'cx, 'tcx>,
     ) -> Option<InitIndex> {
-        let mpi = self.move_data.rev_lookup.find_local(local);
+        let mpi = self.move_data.rev_lookup.find_local(local)?;
         let ii = &self.move_data.init_path_map[mpi];
         ii.into_iter().find(|&&index| flow_state.ever_inits.contains(index)).copied()
     }
diff --git a/compiler/rustc_borrowck/src/nll.rs b/compiler/rustc_borrowck/src/nll.rs
index 3f60f5aca..0ea4401a8 100644
--- a/compiler/rustc_borrowck/src/nll.rs
+++ b/compiler/rustc_borrowck/src/nll.rs
@@ -169,10 +169,11 @@ pub(crate) fn compute_regions<'cx, 'tcx>(
     upvars: &[Upvar<'tcx>],
     consumer_options: Option<ConsumerOptions>,
 ) -> NllOutput<'tcx> {
+    let is_polonius_legacy_enabled = infcx.tcx.sess.opts.unstable_opts.polonius.is_legacy_enabled();
     let polonius_input = consumer_options.map(|c| c.polonius_input()).unwrap_or_default()
-        || infcx.tcx.sess.opts.unstable_opts.polonius;
+        || is_polonius_legacy_enabled;
     let polonius_output = consumer_options.map(|c| c.polonius_output()).unwrap_or_default()
-        || infcx.tcx.sess.opts.unstable_opts.polonius;
+        || is_polonius_legacy_enabled;
     let mut all_facts =
         (polonius_input || AllFacts::enabled(infcx.tcx)).then_some(AllFacts::default());
 
@@ -181,22 +182,26 @@ pub(crate) fn compute_regions<'cx, 'tcx>(
     let elements = &Rc::new(RegionValueElements::new(&body));
 
     // Run the MIR type-checker.
-    let MirTypeckResults { constraints, universal_region_relations, opaque_type_values } =
-        type_check::type_check(
-            infcx,
-            param_env,
-            body,
-            promoted,
-            &universal_regions,
-            location_table,
-            borrow_set,
-            &mut all_facts,
-            flow_inits,
-            move_data,
-            elements,
-            upvars,
-            polonius_input,
-        );
+    let MirTypeckResults {
+        constraints,
+        universal_region_relations,
+        opaque_type_values,
+        live_loans,
+    } = type_check::type_check(
+        infcx,
+        param_env,
+        body,
+        promoted,
+        &universal_regions,
+        location_table,
+        borrow_set,
+        &mut all_facts,
+        flow_inits,
+        move_data,
+        elements,
+        upvars,
+        polonius_input,
+    );
 
     if let Some(all_facts) = &mut all_facts {
         let _prof_timer = infcx.tcx.prof.generic_activity("polonius_fact_generation");
@@ -274,6 +279,7 @@ pub(crate) fn compute_regions<'cx, 'tcx>(
         type_tests,
         liveness_constraints,
         elements,
+        live_loans,
     );
 
     // Generate various additional constraints.
diff --git a/compiler/rustc_borrowck/src/path_utils.rs b/compiler/rustc_borrowck/src/path_utils.rs
index ed93a5609..51e318f08 100644
--- a/compiler/rustc_borrowck/src/path_utils.rs
+++ b/compiler/rustc_borrowck/src/path_utils.rs
@@ -137,7 +137,7 @@ pub(super) fn is_active<'tcx>(
 }
 
 /// Determines if a given borrow is borrowing local data
-/// This is called for all Yield expressions on movable generators
+/// This is called for all Yield expressions on movable coroutines
 pub(super) fn borrow_of_local_data(place: Place<'_>) -> bool {
     // Reborrow of already borrowed data is ignored
     // Any errors will be caught on the initial borrow
@@ -165,7 +165,7 @@ pub(crate) fn is_upvar_field_projection<'tcx>(
     match place_ref.last_projection() {
         Some((place_base, ProjectionElem::Field(field, _ty))) => {
             let base_ty = place_base.ty(body, tcx).ty;
-            if (base_ty.is_closure() || base_ty.is_generator())
+            if (base_ty.is_closure() || base_ty.is_coroutine())
                 && (!by_ref || upvars[field.index()].by_ref)
             {
                 Some(field)
diff --git a/compiler/rustc_borrowck/src/region_infer/mod.rs b/compiler/rustc_borrowck/src/region_infer/mod.rs
index 852935676..b1f91a056 100644
--- a/compiler/rustc_borrowck/src/region_infer/mod.rs
+++ b/compiler/rustc_borrowck/src/region_infer/mod.rs
@@ -7,6 +7,7 @@ use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
 use rustc_data_structures::graph::scc::Sccs;
 use rustc_errors::Diagnostic;
 use rustc_hir::def_id::CRATE_DEF_ID;
+use rustc_index::bit_set::SparseBitMatrix;
 use rustc_index::{IndexSlice, IndexVec};
 use rustc_infer::infer::outlives::test_type_match;
 use rustc_infer::infer::region_constraints::{GenericKind, VarInfos, VerifyBound, VerifyIfEq};
@@ -21,17 +22,17 @@ use rustc_middle::traits::ObligationCauseCode;
 use rustc_middle::ty::{self, RegionVid, Ty, TyCtxt, TypeFoldable, TypeVisitableExt};
 use rustc_span::Span;
 
+use crate::constraints::graph::{self, NormalConstraintGraph, RegionGraph};
+use crate::dataflow::BorrowIndex;
 use crate::{
-    constraints::{
-        graph::NormalConstraintGraph, ConstraintSccIndex, OutlivesConstraint, OutlivesConstraintSet,
-    },
+    constraints::{ConstraintSccIndex, OutlivesConstraint, OutlivesConstraintSet},
     diagnostics::{RegionErrorKind, RegionErrors, UniverseInfo},
     member_constraints::{MemberConstraintSet, NllMemberConstraintIndex},
     nll::PoloniusOutput,
     region_infer::reverse_sccs::ReverseSccGraph,
     region_infer::values::{
-        LivenessValues, PlaceholderIndices, RegionElement, RegionValueElements, RegionValues,
-        ToElementIndex,
+        LivenessValues, PlaceholderIndices, PointIndex, RegionElement, RegionValueElements,
+        RegionValues, ToElementIndex,
     },
     type_check::{free_region_relations::UniversalRegionRelations, Locations},
     universal_regions::UniversalRegions,
@@ -119,6 +120,9 @@ pub struct RegionInferenceContext<'tcx> {
     /// Information about how the universally quantified regions in
     /// scope on this function relate to one another.
     universal_region_relations: Frozen<UniversalRegionRelations<'tcx>>,
+
+    /// The set of loans that are live at a given point in the CFG, when using `-Zpolonius=next`.
+    live_loans: SparseBitMatrix<PointIndex, BorrowIndex>,
 }
 
 /// Each time that `apply_member_constraint` is successful, it appends
@@ -330,6 +334,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         type_tests: Vec<TypeTest<'tcx>>,
         liveness_constraints: LivenessValues<RegionVid>,
         elements: &Rc<RegionValueElements>,
+        live_loans: SparseBitMatrix<PointIndex, BorrowIndex>,
     ) -> Self {
         debug!("universal_regions: {:#?}", universal_regions);
         debug!("outlives constraints: {:#?}", outlives_constraints);
@@ -383,6 +388,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             type_tests,
             universal_regions,
             universal_region_relations,
+            live_loans,
         };
 
         result.init_free_and_bound_regions();
@@ -637,11 +643,12 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         self.scc_universes[scc]
     }
 
-    /// Once region solving has completed, this function will return
-    /// the member constraints that were applied to the value of a given
-    /// region `r`. See `AppliedMemberConstraint`.
-    pub(crate) fn applied_member_constraints(&self, r: RegionVid) -> &[AppliedMemberConstraint] {
-        let scc = self.constraint_sccs.scc(r);
+    /// Once region solving has completed, this function will return the member constraints that
+    /// were applied to the value of a given SCC `scc`. See `AppliedMemberConstraint`.
+    pub(crate) fn applied_member_constraints(
+        &self,
+        scc: ConstraintSccIndex,
+    ) -> &[AppliedMemberConstraint] {
         binary_search_util::binary_search_slice(
             &self.member_constraints_applied,
             |applied| applied.member_region_scc,
@@ -683,7 +690,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         // In Polonius mode, the errors about missing universal region relations are in the output
         // and need to be emitted or propagated. Otherwise, we need to check whether the
         // constraints were too strong, and if so, emit or propagate those errors.
-        if infcx.tcx.sess.opts.unstable_opts.polonius {
+        if infcx.tcx.sess.opts.unstable_opts.polonius.is_legacy_enabled() {
             self.check_polonius_subset_errors(
                 outlives_requirements.as_mut(),
                 &mut errors_buffer,
@@ -1938,7 +1945,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             // Member constraints can also give rise to `'r: 'x` edges that
             // were not part of the graph initially, so watch out for those.
             // (But they are extremely rare; this loop is very cold.)
-            for constraint in self.applied_member_constraints(r) {
+            for constraint in self.applied_member_constraints(self.constraint_sccs.scc(r)) {
                 let p_c = &self.member_constraints[constraint.member_constraint_index];
                 let constraint = OutlivesConstraint {
                     sup: r,
@@ -2279,6 +2286,38 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         }
         None
     }
+
+    /// Access to the SCC constraint graph.
+    pub(crate) fn constraint_sccs(&self) -> &Sccs<RegionVid, ConstraintSccIndex> {
+        self.constraint_sccs.as_ref()
+    }
+
+    /// Access to the region graph, built from the outlives constraints.
+    pub(crate) fn region_graph(&self) -> RegionGraph<'_, 'tcx, graph::Normal> {
+        self.constraint_graph.region_graph(&self.constraints, self.universal_regions.fr_static)
+    }
+
+    /// Returns whether the given region is considered live at all points: whether it is a
+    /// placeholder or a free region.
+    pub(crate) fn is_region_live_at_all_points(&self, region: RegionVid) -> bool {
+        // FIXME: there must be a cleaner way to find this information. At least, when
+        // higher-ranked subtyping is abstracted away from the borrowck main path, we'll only
+        // need to check whether this is a universal region.
+        let origin = self.region_definition(region).origin;
+        let live_at_all_points = matches!(
+            origin,
+            NllRegionVariableOrigin::Placeholder(_) | NllRegionVariableOrigin::FreeRegion
+        );
+        live_at_all_points
+    }
+
+    /// Returns whether the `loan_idx` is live at the given `location`: whether its issuing
+    /// region is contained within the type of a variable that is live at this point.
+    /// Note: for now, the sets of live loans is only available when using `-Zpolonius=next`.
+    pub(crate) fn is_loan_live_at(&self, loan_idx: BorrowIndex, location: Location) -> bool {
+        let point = self.liveness_constraints.point_from_location(location);
+        self.live_loans.contains(point, loan_idx)
+    }
 }
 
 impl<'tcx> RegionDefinition<'tcx> {
diff --git a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
index 4da7b6025..fb0e5811c 100644
--- a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
+++ b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
@@ -1,5 +1,6 @@
 use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
 use rustc_errors::ErrorGuaranteed;
+use rustc_hir::def::DefKind;
 use rustc_hir::def_id::LocalDefId;
 use rustc_hir::OpaqueTyOrigin;
 use rustc_infer::infer::InferCtxt;
@@ -308,20 +309,19 @@ fn check_opaque_type_well_formed<'tcx>(
         return Ok(definition_ty);
     };
     let param_env = tcx.param_env(def_id);
-    // HACK This bubble is required for this tests to pass:
-    // nested-return-type2-tait2.rs
-    // nested-return-type2-tait3.rs
+
+    let mut parent_def_id = def_id;
+    while tcx.def_kind(parent_def_id) == DefKind::OpaqueTy {
+        parent_def_id = tcx.local_parent(parent_def_id);
+    }
+
     // FIXME(-Ztrait-solver=next): We probably should use `DefiningAnchor::Error`
     // and prepopulate this `InferCtxt` with known opaque values, rather than
     // using the `Bind` anchor here. For now it's fine.
     let infcx = tcx
         .infer_ctxt()
         .with_next_trait_solver(next_trait_solver)
-        .with_opaque_type_inference(if next_trait_solver {
-            DefiningAnchor::Bind(def_id)
-        } else {
-            DefiningAnchor::Bubble
-        })
+        .with_opaque_type_inference(DefiningAnchor::Bind(parent_def_id))
         .build();
     let ocx = ObligationCtxt::new(&infcx);
     let identity_args = GenericArgs::identity_for_item(tcx, def_id);
@@ -361,7 +361,7 @@ fn check_opaque_type_well_formed<'tcx>(
     if errors.is_empty() {
         Ok(definition_ty)
     } else {
-        Err(infcx.err_ctxt().report_fulfillment_errors(&errors))
+        Err(infcx.err_ctxt().report_fulfillment_errors(errors))
     }
 }
 
diff --git a/compiler/rustc_borrowck/src/region_infer/values.rs b/compiler/rustc_borrowck/src/region_infer/values.rs
index d205862cd..38452df32 100644
--- a/compiler/rustc_borrowck/src/region_infer/values.rs
+++ b/compiler/rustc_borrowck/src/region_infer/values.rs
@@ -176,6 +176,11 @@ impl<N: Idx> LivenessValues<N> {
     pub(crate) fn region_value_str(&self, r: N) -> String {
         region_value_str(self.get_elements(r).map(RegionElement::Location))
     }
+
+    #[inline]
+    pub(crate) fn point_from_location(&self, location: Location) -> PointIndex {
+        self.elements.point_from_location(location)
+    }
 }
 
 /// Maps from `ty::PlaceholderRegion` values that are used in the rest of
diff --git a/compiler/rustc_borrowck/src/renumber.rs b/compiler/rustc_borrowck/src/renumber.rs
index 5d6f5cc89..ec0131c53 100644
--- a/compiler/rustc_borrowck/src/renumber.rs
+++ b/compiler/rustc_borrowck/src/renumber.rs
@@ -81,6 +81,10 @@ impl<'a, 'tcx> MutVisitor<'tcx> for RegionRenumberer<'a, 'tcx> {
 
     #[instrument(skip(self), level = "debug")]
     fn visit_ty(&mut self, ty: &mut Ty<'tcx>, ty_context: TyContext) {
+        if matches!(ty_context, TyContext::ReturnTy(_)) {
+            // We will renumber the return ty when called again with `TyContext::LocalDecl`
+            return;
+        }
         *ty = self.renumber_regions(*ty, || RegionCtxt::TyContext(ty_context));
 
         debug!(?ty);
diff --git a/compiler/rustc_borrowck/src/session_diagnostics.rs b/compiler/rustc_borrowck/src/session_diagnostics.rs
index ca3ccf439..e321b9260 100644
--- a/compiler/rustc_borrowck/src/session_diagnostics.rs
+++ b/compiler/rustc_borrowck/src/session_diagnostics.rs
@@ -139,23 +139,23 @@ pub(crate) enum RequireStaticErr {
 
 #[derive(Subdiagnostic)]
 pub(crate) enum CaptureVarPathUseCause {
-    #[label(borrowck_borrow_due_to_use_generator)]
-    BorrowInGenerator {
+    #[label(borrowck_borrow_due_to_use_coroutine)]
+    BorrowInCoroutine {
         #[primary_span]
         path_span: Span,
     },
-    #[label(borrowck_use_due_to_use_generator)]
-    UseInGenerator {
+    #[label(borrowck_use_due_to_use_coroutine)]
+    UseInCoroutine {
         #[primary_span]
         path_span: Span,
     },
-    #[label(borrowck_assign_due_to_use_generator)]
-    AssignInGenerator {
+    #[label(borrowck_assign_due_to_use_coroutine)]
+    AssignInCoroutine {
         #[primary_span]
         path_span: Span,
     },
-    #[label(borrowck_assign_part_due_to_use_generator)]
-    AssignPartInGenerator {
+    #[label(borrowck_assign_part_due_to_use_coroutine)]
+    AssignPartInCoroutine {
         #[primary_span]
         path_span: Span,
     },
@@ -202,8 +202,8 @@ pub(crate) enum CaptureVarKind {
 
 #[derive(Subdiagnostic)]
 pub(crate) enum CaptureVarCause {
-    #[label(borrowck_var_borrow_by_use_place_in_generator)]
-    BorrowUsePlaceGenerator {
+    #[label(borrowck_var_borrow_by_use_place_in_coroutine)]
+    BorrowUsePlaceCoroutine {
         is_single_var: bool,
         place: String,
         #[primary_span]
@@ -216,8 +216,8 @@ pub(crate) enum CaptureVarCause {
         #[primary_span]
         var_span: Span,
     },
-    #[label(borrowck_var_borrow_by_use_in_generator)]
-    BorrowUseInGenerator {
+    #[label(borrowck_var_borrow_by_use_in_coroutine)]
+    BorrowUseInCoroutine {
         #[primary_span]
         var_span: Span,
     },
@@ -226,8 +226,8 @@ pub(crate) enum CaptureVarCause {
         #[primary_span]
         var_span: Span,
     },
-    #[label(borrowck_var_move_by_use_in_generator)]
-    MoveUseInGenerator {
+    #[label(borrowck_var_move_by_use_in_coroutine)]
+    MoveUseInCoroutine {
         #[primary_span]
         var_span: Span,
     },
@@ -236,8 +236,8 @@ pub(crate) enum CaptureVarCause {
         #[primary_span]
         var_span: Span,
     },
-    #[label(borrowck_var_first_borrow_by_use_place_in_generator)]
-    FirstBorrowUsePlaceGenerator {
+    #[label(borrowck_var_first_borrow_by_use_place_in_coroutine)]
+    FirstBorrowUsePlaceCoroutine {
         place: String,
         #[primary_span]
         var_span: Span,
@@ -248,8 +248,8 @@ pub(crate) enum CaptureVarCause {
         #[primary_span]
         var_span: Span,
     },
-    #[label(borrowck_var_second_borrow_by_use_place_in_generator)]
-    SecondBorrowUsePlaceGenerator {
+    #[label(borrowck_var_second_borrow_by_use_place_in_coroutine)]
+    SecondBorrowUsePlaceCoroutine {
         place: String,
         #[primary_span]
         var_span: Span,
@@ -266,8 +266,8 @@ pub(crate) enum CaptureVarCause {
         #[primary_span]
         var_span: Span,
     },
-    #[label(borrowck_partial_var_move_by_use_in_generator)]
-    PartialMoveUseInGenerator {
+    #[label(borrowck_partial_var_move_by_use_in_coroutine)]
+    PartialMoveUseInCoroutine {
         #[primary_span]
         var_span: Span,
         is_partial: bool,
diff --git a/compiler/rustc_borrowck/src/type_check/canonical.rs b/compiler/rustc_borrowck/src/type_check/canonical.rs
index b7adc314f..fc600af1b 100644
--- a/compiler/rustc_borrowck/src/type_check/canonical.rs
+++ b/compiler/rustc_borrowck/src/type_check/canonical.rs
@@ -49,7 +49,9 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         // If the query has created new universes and errors are going to be emitted, register the
         // cause of these new universes for improved diagnostics.
         let universe = self.infcx.universe();
-        if old_universe != universe && let Some(error_info) = error_info {
+        if old_universe != universe
+            && let Some(error_info) = error_info
+        {
             let universe_info = error_info.to_universe_info(old_universe);
             for u in (old_universe + 1)..=universe {
                 self.borrowck_context.constraints.universe_causes.insert(u, universe_info.clone());
diff --git a/compiler/rustc_borrowck/src/type_check/free_region_relations.rs b/compiler/rustc_borrowck/src/type_check/free_region_relations.rs
index f22851d76..c84256f8f 100644
--- a/compiler/rustc_borrowck/src/type_check/free_region_relations.rs
+++ b/compiler/rustc_borrowck/src/type_check/free_region_relations.rs
@@ -8,7 +8,7 @@ use rustc_infer::infer::InferCtxt;
 use rustc_middle::mir::ConstraintCategory;
 use rustc_middle::traits::query::OutlivesBound;
 use rustc_middle::ty::{self, RegionVid, Ty};
-use rustc_span::{Span, DUMMY_SP};
+use rustc_span::{ErrorGuaranteed, Span, DUMMY_SP};
 use rustc_trait_selection::traits::query::type_op::{self, TypeOp};
 use std::rc::Rc;
 use type_op::TypeOpOutput;
@@ -318,7 +318,8 @@ impl<'tcx> UniversalRegionRelationsBuilder<'_, 'tcx> {
             .param_env
             .and(type_op::implied_outlives_bounds::ImpliedOutlivesBounds { ty })
             .fully_perform(self.infcx, DUMMY_SP)
-            .unwrap_or_else(|_| bug!("failed to compute implied bounds {:?}", ty));
+            .map_err(|_: ErrorGuaranteed| debug!("failed to compute implied bounds {:?}", ty))
+            .ok()?;
         debug!(?bounds, ?constraints);
         self.add_outlives_bounds(bounds);
         constraints
diff --git a/compiler/rustc_borrowck/src/type_check/input_output.rs b/compiler/rustc_borrowck/src/type_check/input_output.rs
index eec886b7b..d053d0a4b 100644
--- a/compiler/rustc_borrowck/src/type_check/input_output.rs
+++ b/compiler/rustc_borrowck/src/type_check/input_output.rs
@@ -101,7 +101,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         );
 
         // We will not have a universal_regions.yield_ty if we yield (by accident)
-        // outside of a generator and return an `impl Trait`, so emit a delay_span_bug
+        // outside of a coroutine and return an `impl Trait`, so emit a delay_span_bug
         // because we don't want to panic in an assert here if we've already got errors.
         if body.yield_ty().is_some() != universal_regions.yield_ty.is_some() {
             self.tcx().sess.delay_span_bug(
diff --git a/compiler/rustc_borrowck/src/type_check/liveness/trace.rs b/compiler/rustc_borrowck/src/type_check/liveness/trace.rs
index 5702d39db..e616449cc 100644
--- a/compiler/rustc_borrowck/src/type_check/liveness/trace.rs
+++ b/compiler/rustc_borrowck/src/type_check/liveness/trace.rs
@@ -1,10 +1,12 @@
 use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
-use rustc_index::bit_set::HybridBitSet;
+use rustc_data_structures::graph::WithSuccessors;
+use rustc_index::bit_set::{HybridBitSet, SparseBitMatrix};
 use rustc_index::interval::IntervalSet;
 use rustc_infer::infer::canonical::QueryRegionConstraints;
+use rustc_infer::infer::outlives::for_liveness;
 use rustc_middle::mir::{BasicBlock, Body, ConstraintCategory, Local, Location};
 use rustc_middle::traits::query::DropckOutlivesResult;
-use rustc_middle::ty::{Ty, TyCtxt, TypeVisitable, TypeVisitableExt};
+use rustc_middle::ty::{RegionVid, Ty, TyCtxt, TypeVisitable, TypeVisitableExt};
 use rustc_span::DUMMY_SP;
 use rustc_trait_selection::traits::query::type_op::outlives::DropckOutlives;
 use rustc_trait_selection::traits::query::type_op::{TypeOp, TypeOpOutput};
@@ -14,6 +16,7 @@ use rustc_mir_dataflow::impls::MaybeInitializedPlaces;
 use rustc_mir_dataflow::move_paths::{HasMoveData, MoveData, MovePathIndex};
 use rustc_mir_dataflow::ResultsCursor;
 
+use crate::dataflow::BorrowIndex;
 use crate::{
     region_infer::values::{self, PointIndex, RegionValueElements},
     type_check::liveness::local_use_map::LocalUseMap,
@@ -50,6 +53,33 @@ pub(super) fn trace<'mir, 'tcx>(
 
     let local_use_map = &LocalUseMap::build(&relevant_live_locals, elements, body);
 
+    // When using `-Zpolonius=next`, compute the set of loans that can reach a given region.
+    let num_loans = typeck.borrowck_context.borrow_set.len();
+    let mut inflowing_loans = SparseBitMatrix::new(num_loans);
+    if typeck.tcx().sess.opts.unstable_opts.polonius.is_next_enabled() {
+        let borrowck_context = &typeck.borrowck_context;
+        let borrow_set = &borrowck_context.borrow_set;
+        let constraint_set = &borrowck_context.constraints.outlives_constraints;
+
+        let num_region_vars = typeck.infcx.num_region_vars();
+        let graph = constraint_set.graph(num_region_vars);
+        let region_graph =
+            graph.region_graph(&constraint_set, borrowck_context.universal_regions.fr_static);
+
+        // Traverse each issuing region's constraints, and record the loan as flowing into the
+        // outlived region.
+        for (loan, issuing_region_data) in borrow_set.iter_enumerated() {
+            for succ in region_graph.depth_first_search(issuing_region_data.region) {
+                // We don't need to mention that a loan flows into its issuing region.
+                if succ == issuing_region_data.region {
+                    continue;
+                }
+
+                inflowing_loans.insert(succ, loan);
+            }
+        }
+    };
+
     let cx = LivenessContext {
         typeck,
         body,
@@ -58,6 +88,7 @@ pub(super) fn trace<'mir, 'tcx>(
         local_use_map,
         move_data,
         drop_data: FxIndexMap::default(),
+        inflowing_loans,
     };
 
     let mut results = LivenessResults::new(cx);
@@ -71,7 +102,7 @@ pub(super) fn trace<'mir, 'tcx>(
     results.dropck_boring_locals(boring_locals);
 }
 
-/// Contextual state for the type-liveness generator.
+/// Contextual state for the type-liveness coroutine.
 struct LivenessContext<'me, 'typeck, 'flow, 'tcx> {
     /// Current type-checker, giving us our inference context etc.
     typeck: &'me mut TypeChecker<'typeck, 'tcx>,
@@ -95,6 +126,9 @@ struct LivenessContext<'me, 'typeck, 'flow, 'tcx> {
     /// Index indicating where each variable is assigned, used, or
     /// dropped.
     local_use_map: &'me LocalUseMap,
+
+    /// Set of loans that flow into a given region, when using `-Zpolonius=next`.
+    inflowing_loans: SparseBitMatrix<RegionVid, BorrowIndex>,
 }
 
 struct DropData<'tcx> {
@@ -284,7 +318,7 @@ impl<'me, 'typeck, 'flow, 'tcx> LivenessResults<'me, 'typeck, 'flow, 'tcx> {
     fn compute_drop_live_points_for(&mut self, local: Local) {
         debug!("compute_drop_live_points_for(local={:?})", local);
 
-        let mpi = self.cx.move_data.rev_lookup.find_local(local);
+        let Some(mpi) = self.cx.move_data.rev_lookup.find_local(local) else { return };
         debug!("compute_drop_live_points_for: mpi = {:?}", mpi);
 
         // Find the drops where `local` is initialized.
@@ -486,7 +520,13 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> {
     ) {
         debug!("add_use_live_facts_for(value={:?})", value);
 
-        Self::make_all_regions_live(self.elements, &mut self.typeck, value, live_at)
+        Self::make_all_regions_live(
+            self.elements,
+            &mut self.typeck,
+            value,
+            live_at,
+            &self.inflowing_loans,
+        );
     }
 
     /// Some variable with type `live_ty` is "drop live" at `location`
@@ -537,7 +577,13 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> {
         // All things in the `outlives` array may be touched by
         // the destructor and must be live at this point.
         for &kind in &drop_data.dropck_result.kinds {
-            Self::make_all_regions_live(self.elements, &mut self.typeck, kind, live_at);
+            Self::make_all_regions_live(
+                self.elements,
+                &mut self.typeck,
+                kind,
+                live_at,
+                &self.inflowing_loans,
+            );
 
             polonius::add_drop_of_var_derefs_origin(&mut self.typeck, dropped_local, &kind);
         }
@@ -548,6 +594,7 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> {
         typeck: &mut TypeChecker<'_, 'tcx>,
         value: impl TypeVisitable<TyCtxt<'tcx>>,
         live_at: &IntervalSet<PointIndex>,
+        inflowing_loans: &SparseBitMatrix<RegionVid, BorrowIndex>,
     ) {
         debug!("make_all_regions_live(value={:?})", value);
         debug!(
@@ -555,16 +602,38 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> {
             values::location_set_str(elements, live_at.iter()),
         );
 
-        let tcx = typeck.tcx();
-        tcx.for_each_free_region(&value, |live_region| {
-            let live_region_vid =
-                typeck.borrowck_context.universal_regions.to_region_vid(live_region);
-            typeck
-                .borrowck_context
-                .constraints
-                .liveness_constraints
-                .add_elements(live_region_vid, live_at);
+        // When using `-Zpolonius=next`, we want to record the loans that flow into this value's
+        // regions as being live at the given `live_at` points: this will be used to compute the
+        // location where a loan goes out of scope.
+        let num_loans = typeck.borrowck_context.borrow_set.len();
+        let value_loans = &mut HybridBitSet::new_empty(num_loans);
+
+        value.visit_with(&mut for_liveness::FreeRegionsVisitor {
+            tcx: typeck.tcx(),
+            param_env: typeck.param_env,
+            op: |r| {
+                let live_region_vid = typeck.borrowck_context.universal_regions.to_region_vid(r);
+
+                typeck
+                    .borrowck_context
+                    .constraints
+                    .liveness_constraints
+                    .add_elements(live_region_vid, live_at);
+
+                // There can only be inflowing loans for this region when we are using
+                // `-Zpolonius=next`.
+                if let Some(inflowing) = inflowing_loans.row(live_region_vid) {
+                    value_loans.union(inflowing);
+                }
+            },
         });
+
+        // Record the loans reaching the value.
+        if !value_loans.is_empty() {
+            for point in live_at.iter() {
+                typeck.borrowck_context.live_loans.union_row(point, value_loans);
+            }
+        }
     }
 
     fn compute_drop_data(
diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs
index 1f383e533..608d01039 100644
--- a/compiler/rustc_borrowck/src/type_check/mod.rs
+++ b/compiler/rustc_borrowck/src/type_check/mod.rs
@@ -14,6 +14,7 @@ use rustc_hir as hir;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::LocalDefId;
 use rustc_hir::lang_items::LangItem;
+use rustc_index::bit_set::SparseBitMatrix;
 use rustc_index::{IndexSlice, IndexVec};
 use rustc_infer::infer::canonical::QueryRegionConstraints;
 use rustc_infer::infer::outlives::env::RegionBoundPairs;
@@ -50,6 +51,8 @@ use rustc_mir_dataflow::impls::MaybeInitializedPlaces;
 use rustc_mir_dataflow::move_paths::MoveData;
 use rustc_mir_dataflow::ResultsCursor;
 
+use crate::dataflow::BorrowIndex;
+use crate::region_infer::values::PointIndex;
 use crate::session_diagnostics::{MoveUnsized, SimdShuffleLastConst};
 use crate::{
     borrow_set::BorrowSet,
@@ -163,6 +166,9 @@ pub(crate) fn type_check<'mir, 'tcx>(
 
     debug!(?normalized_inputs_and_output);
 
+    // When using `-Zpolonius=next`, liveness will record the set of live loans per point.
+    let mut live_loans = SparseBitMatrix::new(borrow_set.len());
+
     let mut borrowck_context = BorrowCheckContext {
         universal_regions,
         location_table,
@@ -170,6 +176,7 @@ pub(crate) fn type_check<'mir, 'tcx>(
         all_facts,
         constraints: &mut constraints,
         upvars,
+        live_loans: &mut live_loans,
     };
 
     let mut checker = TypeChecker::new(
@@ -181,11 +188,7 @@ pub(crate) fn type_check<'mir, 'tcx>(
         &mut borrowck_context,
     );
 
-    // FIXME(-Ztrait-solver=next): A bit dubious that we're only registering
-    // predefined opaques in the typeck root.
-    if infcx.next_trait_solver() && !infcx.tcx.is_typeck_child(body.source.def_id()) {
-        checker.register_predefined_opaques_in_new_solver();
-    }
+    checker.check_user_type_annotations();
 
     let mut verifier = TypeVerifier::new(&mut checker, promoted);
     verifier.visit_body(&body);
@@ -240,7 +243,7 @@ pub(crate) fn type_check<'mir, 'tcx>(
         })
         .collect();
 
-    MirTypeckResults { constraints, universal_region_relations, opaque_type_values }
+    MirTypeckResults { constraints, universal_region_relations, opaque_type_values, live_loans }
 }
 
 fn translate_outlives_facts(typeck: &mut TypeChecker<'_, '_>) {
@@ -664,8 +667,8 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
                         PlaceTy { ty: base_ty, variant_index: Some(index) }
                     }
                 }
-                // We do not need to handle generators here, because this runs
-                // before the generator transform stage.
+                // We do not need to handle coroutines here, because this runs
+                // before the coroutine transform stage.
                 _ => {
                     let ty = if let Some(name) = maybe_name {
                         span_mirbug_and_err!(
@@ -767,13 +770,13 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
         let (variant, args) = match base_ty {
             PlaceTy { ty, variant_index: Some(variant_index) } => match *ty.kind() {
                 ty::Adt(adt_def, args) => (adt_def.variant(variant_index), args),
-                ty::Generator(def_id, args, _) => {
-                    let mut variants = args.as_generator().state_tys(def_id, tcx);
+                ty::Coroutine(def_id, args, _) => {
+                    let mut variants = args.as_coroutine().state_tys(def_id, tcx);
                     let Some(mut variant) = variants.nth(variant_index.into()) else {
                         bug!(
-                            "variant_index of generator out of range: {:?}/{:?}",
+                            "variant_index of coroutine out of range: {:?}/{:?}",
                             variant_index,
-                            args.as_generator().state_tys(def_id, tcx).count()
+                            args.as_coroutine().state_tys(def_id, tcx).count()
                         );
                     };
                     return match variant.nth(field.index()) {
@@ -781,7 +784,7 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
                         None => Err(FieldAccessError::OutOfRange { field_count: variant.count() }),
                     };
                 }
-                _ => bug!("can't have downcast of non-adt non-generator type"),
+                _ => bug!("can't have downcast of non-adt non-coroutine type"),
             },
             PlaceTy { ty, variant_index: None } => match *ty.kind() {
                 ty::Adt(adt_def, args) if !adt_def.is_enum() => {
@@ -795,13 +798,13 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
                         }),
                     };
                 }
-                ty::Generator(_, args, _) => {
+                ty::Coroutine(_, args, _) => {
                     // Only prefix fields (upvars and current state) are
                     // accessible without a variant index.
-                    return match args.as_generator().prefix_tys().get(field.index()) {
+                    return match args.as_coroutine().prefix_tys().get(field.index()) {
                         Some(ty) => Ok(*ty),
                         None => Err(FieldAccessError::OutOfRange {
-                            field_count: args.as_generator().prefix_tys().len(),
+                            field_count: args.as_coroutine().prefix_tys().len(),
                         }),
                     };
                 }
@@ -855,12 +858,21 @@ struct BorrowCheckContext<'a, 'tcx> {
     borrow_set: &'a BorrowSet<'tcx>,
     pub(crate) constraints: &'a mut MirTypeckRegionConstraints<'tcx>,
     upvars: &'a [Upvar<'tcx>],
+
+    /// The set of loans that are live at a given point in the CFG, filled in by `liveness::trace`,
+    /// when using `-Zpolonius=next`.
+    pub(crate) live_loans: &'a mut SparseBitMatrix<PointIndex, BorrowIndex>,
 }
 
+/// Holder struct for passing results from MIR typeck to the rest of the non-lexical regions
+/// inference computation.
 pub(crate) struct MirTypeckResults<'tcx> {
     pub(crate) constraints: MirTypeckRegionConstraints<'tcx>,
     pub(crate) universal_region_relations: Frozen<UniversalRegionRelations<'tcx>>,
     pub(crate) opaque_type_values: FxIndexMap<OpaqueTypeKey<'tcx>, OpaqueHiddenType<'tcx>>,
+
+    /// The set of loans that are live at a given point in the CFG, when using `-Zpolonius=next`.
+    pub(crate) live_loans: SparseBitMatrix<PointIndex, BorrowIndex>,
 }
 
 /// A collection of region constraints that must be satisfied for the
@@ -1005,7 +1017,13 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             borrowck_context,
             reported_errors: Default::default(),
         };
-        checker.check_user_type_annotations();
+
+        // FIXME(-Ztrait-solver=next): A bit dubious that we're only registering
+        // predefined opaques in the typeck root.
+        if infcx.next_trait_solver() && !infcx.tcx.is_typeck_child(body.source.def_id()) {
+            checker.register_predefined_opaques_in_new_solver();
+        }
+
         checker
     }
 
@@ -1335,7 +1353,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             | TerminatorKind::UnwindResume
             | TerminatorKind::UnwindTerminate(_)
             | TerminatorKind::Return
-            | TerminatorKind::GeneratorDrop
+            | TerminatorKind::CoroutineDrop
             | TerminatorKind::Unreachable
             | TerminatorKind::Drop { .. }
             | TerminatorKind::FalseEdge { .. }
@@ -1452,7 +1470,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
 
                 let value_ty = value.ty(body, tcx);
                 match body.yield_ty() {
-                    None => span_mirbug!(self, term, "yield in non-generator"),
+                    None => span_mirbug!(self, term, "yield in non-coroutine"),
                     Some(ty) => {
                         if let Err(terr) = self.sub_types(
                             value_ty,
@@ -1624,7 +1642,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             }
             TerminatorKind::UnwindTerminate(_) => {
                 if !is_cleanup {
-                    span_mirbug!(self, block_data, "abort on non-cleanup block!")
+                    span_mirbug!(self, block_data, "terminate on non-cleanup block!")
                 }
             }
             TerminatorKind::Return => {
@@ -1632,9 +1650,9 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                     span_mirbug!(self, block_data, "return on cleanup block")
                 }
             }
-            TerminatorKind::GeneratorDrop { .. } => {
+            TerminatorKind::CoroutineDrop { .. } => {
                 if is_cleanup {
-                    span_mirbug!(self, block_data, "generator_drop in cleanup block")
+                    span_mirbug!(self, block_data, "coroutine_drop in cleanup block")
                 }
             }
             TerminatorKind::Yield { resume, drop, .. } => {
@@ -1781,14 +1799,14 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                     }),
                 }
             }
-            AggregateKind::Generator(_, args, _) => {
+            AggregateKind::Coroutine(_, args, _) => {
                 // It doesn't make sense to look at a field beyond the prefix;
                 // these require a variant index, and are not initialized in
                 // aggregate rvalues.
-                match args.as_generator().prefix_tys().get(field_index.as_usize()) {
+                match args.as_coroutine().prefix_tys().get(field_index.as_usize()) {
                     Some(ty) => Ok(*ty),
                     None => Err(FieldAccessError::OutOfRange {
-                        field_count: args.as_generator().prefix_tys().len(),
+                        field_count: args.as_coroutine().prefix_tys().len(),
                     }),
                 }
             }
@@ -2381,7 +2399,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                 AggregateKind::Array(_) => None,
                 AggregateKind::Tuple => None,
                 AggregateKind::Closure(_, _) => None,
-                AggregateKind::Generator(_, _, _) => None,
+                AggregateKind::Coroutine(_, _, _) => None,
             },
         }
     }
@@ -2609,7 +2627,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             // desugaring. A closure gets desugared to a struct, and
             // these extra requirements are basically like where
             // clauses on the struct.
-            AggregateKind::Closure(def_id, args) | AggregateKind::Generator(def_id, args, _) => {
+            AggregateKind::Closure(def_id, args) | AggregateKind::Coroutine(def_id, args, _) => {
                 (def_id, self.prove_closure_bounds(tcx, def_id.expect_local(), args, location))
             }
 
@@ -2657,7 +2675,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
 
         let parent_args = match tcx.def_kind(def_id) {
             DefKind::Closure => args.as_closure().parent_args(),
-            DefKind::Generator => args.as_generator().parent_args(),
+            DefKind::Coroutine => args.as_coroutine().parent_args(),
             DefKind::InlineConst => args.as_inline_const().parent_args(),
             other => bug!("unexpected item {:?}", other),
         };
diff --git a/compiler/rustc_borrowck/src/universal_regions.rs b/compiler/rustc_borrowck/src/universal_regions.rs
index af437f36b..7897a5a63 100644
--- a/compiler/rustc_borrowck/src/universal_regions.rs
+++ b/compiler/rustc_borrowck/src/universal_regions.rs
@@ -58,7 +58,7 @@ pub struct UniversalRegions<'tcx> {
     num_universals: usize,
 
     /// The "defining" type for this function, with all universal
-    /// regions instantiated. For a closure or generator, this is the
+    /// regions instantiated. For a closure or coroutine, this is the
     /// closure type, but for a top-level function it's the `FnDef`.
     pub defining_ty: DefiningTy<'tcx>,
 
@@ -91,10 +91,10 @@ pub enum DefiningTy<'tcx> {
     /// `ClosureArgs::closure_sig_ty`.
     Closure(DefId, GenericArgsRef<'tcx>),
 
-    /// The MIR is a generator. The signature is that generators take
+    /// The MIR is a coroutine. The signature is that coroutines take
     /// no parameters and return the result of
-    /// `ClosureArgs::generator_return_ty`.
-    Generator(DefId, GenericArgsRef<'tcx>, hir::Movability),
+    /// `ClosureArgs::coroutine_return_ty`.
+    Coroutine(DefId, GenericArgsRef<'tcx>, hir::Movability),
 
     /// The MIR is a fn item with the given `DefId` and args. The signature
     /// of the function can be bound then with the `fn_sig` query.
@@ -112,13 +112,13 @@ pub enum DefiningTy<'tcx> {
 
 impl<'tcx> DefiningTy<'tcx> {
     /// Returns a list of all the upvar types for this MIR. If this is
-    /// not a closure or generator, there are no upvars, and hence it
+    /// not a closure or coroutine, there are no upvars, and hence it
     /// will be an empty list. The order of types in this list will
     /// match up with the upvar order in the HIR, typesystem, and MIR.
     pub fn upvar_tys(self) -> &'tcx ty::List<Ty<'tcx>> {
         match self {
             DefiningTy::Closure(_, args) => args.as_closure().upvar_tys(),
-            DefiningTy::Generator(_, args, _) => args.as_generator().upvar_tys(),
+            DefiningTy::Coroutine(_, args, _) => args.as_coroutine().upvar_tys(),
             DefiningTy::FnDef(..) | DefiningTy::Const(..) | DefiningTy::InlineConst(..) => {
                 ty::List::empty()
             }
@@ -130,7 +130,7 @@ impl<'tcx> DefiningTy<'tcx> {
     /// user's code.
     pub fn implicit_inputs(self) -> usize {
         match self {
-            DefiningTy::Closure(..) | DefiningTy::Generator(..) => 1,
+            DefiningTy::Closure(..) | DefiningTy::Coroutine(..) => 1,
             DefiningTy::FnDef(..) | DefiningTy::Const(..) | DefiningTy::InlineConst(..) => 0,
         }
     }
@@ -146,7 +146,7 @@ impl<'tcx> DefiningTy<'tcx> {
     pub fn def_id(&self) -> DefId {
         match *self {
             DefiningTy::Closure(def_id, ..)
-            | DefiningTy::Generator(def_id, ..)
+            | DefiningTy::Coroutine(def_id, ..)
             | DefiningTy::FnDef(def_id, ..)
             | DefiningTy::Const(def_id, ..)
             | DefiningTy::InlineConst(def_id, ..) => def_id,
@@ -164,7 +164,7 @@ struct UniversalRegionIndices<'tcx> {
     /// be able to map them to our internal `RegionVid`. This is
     /// basically equivalent to an `GenericArgs`, except that it also
     /// contains an entry for `ReStatic` -- it might be nice to just
-    /// use a args, and then handle `ReStatic` another way.
+    /// use an args, and then handle `ReStatic` another way.
     indices: FxHashMap<ty::Region<'tcx>, RegionVid>,
 
     /// The vid assigned to `'static`. Used only for diagnostics.
@@ -178,7 +178,7 @@ pub enum RegionClassification {
     Global,
 
     /// An **external** region is only relevant for
-    /// closures, generators, and inline consts. In that
+    /// closures, coroutines, and inline consts. In that
     /// case, it refers to regions that are free in the type
     /// -- basically, something bound in the surrounding context.
     ///
@@ -196,7 +196,7 @@ pub enum RegionClassification {
     /// Here, the lifetimes `'a` and `'b` would be **external** to the
     /// closure.
     ///
-    /// If we are not analyzing a closure/generator/inline-const,
+    /// If we are not analyzing a closure/coroutine/inline-const,
     /// there are no external lifetimes.
     External,
 
@@ -290,7 +290,7 @@ impl<'tcx> UniversalRegions<'tcx> {
         (FIRST_GLOBAL_INDEX..self.num_universals).map(RegionVid::from_usize)
     }
 
-    /// Returns `true` if `r` is classified as an local region.
+    /// Returns `true` if `r` is classified as a local region.
     pub fn is_local_free_region(&self, r: RegionVid) -> bool {
         self.region_classification(r) == Some(RegionClassification::Local)
     }
@@ -354,7 +354,7 @@ impl<'tcx> UniversalRegions<'tcx> {
                     err.note(format!("late-bound region is {:?}", self.to_region_vid(r)));
                 });
             }
-            DefiningTy::Generator(def_id, args, _) => {
+            DefiningTy::Coroutine(def_id, args, _) => {
                 let v = with_no_trimmed_paths!(
                     args[tcx.generics_of(def_id).parent_count..]
                         .iter()
@@ -362,7 +362,7 @@ impl<'tcx> UniversalRegions<'tcx> {
                         .collect::<Vec<_>>()
                 );
                 err.note(format!(
-                    "defining type: {} with generator args [\n    {},\n]",
+                    "defining type: {} with coroutine args [\n    {},\n]",
                     tcx.def_path_str_with_args(def_id, args),
                     v.join(",\n    "),
                 ));
@@ -426,13 +426,13 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
 
         let typeck_root_def_id = self.infcx.tcx.typeck_root_def_id(self.mir_def.to_def_id());
 
-        // If this is a 'root' body (not a closure/generator/inline const), then
+        // If this is a 'root' body (not a closure/coroutine/inline const), then
         // there are no extern regions, so the local regions start at the same
         // position as the (empty) sub-list of extern regions
         let first_local_index = if self.mir_def.to_def_id() == typeck_root_def_id {
             first_extern_index
         } else {
-            // If this is a closure, generator, or inline-const, then the late-bound regions from the enclosing
+            // If this is a closure, coroutine, or inline-const, then the late-bound regions from the enclosing
             // function/closures are actually external regions to us. For example, here, 'a is not local
             // to the closure c (although it is local to the fn foo):
             // fn foo<'a>() {
@@ -528,7 +528,7 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
         debug!("build: local regions  = {}..{}", first_local_index, num_universals);
 
         let yield_ty = match defining_ty {
-            DefiningTy::Generator(_, args, _) => Some(args.as_generator().yield_ty()),
+            DefiningTy::Coroutine(_, args, _) => Some(args.as_coroutine().yield_ty()),
             _ => None,
         };
 
@@ -563,8 +563,8 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
 
                 match *defining_ty.kind() {
                     ty::Closure(def_id, args) => DefiningTy::Closure(def_id, args),
-                    ty::Generator(def_id, args, movability) => {
-                        DefiningTy::Generator(def_id, args, movability)
+                    ty::Coroutine(def_id, args, movability) => {
+                        DefiningTy::Coroutine(def_id, args, movability)
                     }
                     ty::FnDef(def_id, args) => DefiningTy::FnDef(def_id, args),
                     _ => span_bug!(
@@ -621,7 +621,7 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
         let identity_args = GenericArgs::identity_for_item(tcx, typeck_root_def_id);
         let fr_args = match defining_ty {
             DefiningTy::Closure(_, args)
-            | DefiningTy::Generator(_, args, _)
+            | DefiningTy::Coroutine(_, args, _)
             | DefiningTy::InlineConst(_, args) => {
                 // In the case of closures, we rely on the fact that
                 // the first N elements in the ClosureArgs are
@@ -686,13 +686,13 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
                 )
             }
 
-            DefiningTy::Generator(def_id, args, movability) => {
+            DefiningTy::Coroutine(def_id, args, movability) => {
                 assert_eq!(self.mir_def.to_def_id(), def_id);
-                let resume_ty = args.as_generator().resume_ty();
-                let output = args.as_generator().return_ty();
-                let generator_ty = Ty::new_generator(tcx, def_id, args, movability);
+                let resume_ty = args.as_coroutine().resume_ty();
+                let output = args.as_coroutine().return_ty();
+                let coroutine_ty = Ty::new_coroutine(tcx, def_id, args, movability);
                 let inputs_and_output =
-                    self.infcx.tcx.mk_type_list(&[generator_ty, resume_ty, output]);
+                    self.infcx.tcx.mk_type_list(&[coroutine_ty, resume_ty, output]);
                 ty::Binder::dummy(inputs_and_output)
             }