diff --git a/compiler/rustc_ast_lowering/src/index.rs b/compiler/rustc_ast_lowering/src/index.rs
index 26c0e7e5f82a..956cb580d103 100644
--- a/compiler/rustc_ast_lowering/src/index.rs
+++ b/compiler/rustc_ast_lowering/src/index.rs
@@ -164,7 +164,7 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> {
     fn visit_item(&mut self, i: &'hir Item<'hir>) {
         debug_assert_eq!(i.owner_id, self.owner);
         self.with_parent(i.hir_id(), |this| {
-            if let ItemKind::Struct(_, struct_def, _) = &i.kind {
+            if let ItemKind::Struct(_, _, struct_def) = &i.kind {
                 // If this is a tuple or unit-like struct, register the constructor.
                 if let Some(ctor_hir_id) = struct_def.ctor_hir_id() {
                     this.insert(i.span, ctor_hir_id, Node::Ctor(struct_def));
diff --git a/compiler/rustc_ast_lowering/src/item.rs b/compiler/rustc_ast_lowering/src/item.rs
index 7f7d45790ee2..d3aacaa15a8c 100644
--- a/compiler/rustc_ast_lowering/src/item.rs
+++ b/compiler/rustc_ast_lowering/src/item.rs
@@ -180,7 +180,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 let (ty, body_id) =
                     self.lower_const_item(t, span, e.as_deref(), ImplTraitPosition::StaticTy);
                 self.lower_define_opaque(hir_id, define_opaque);
-                hir::ItemKind::Static(ident, ty, *m, body_id)
+                hir::ItemKind::Static(*m, ident, ty, body_id)
             }
             ItemKind::Const(box ast::ConstItem {
                 ident,
@@ -200,7 +200,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     },
                 );
                 self.lower_define_opaque(hir_id, &define_opaque);
-                hir::ItemKind::Const(ident, ty, generics, body_id)
+                hir::ItemKind::Const(ident, generics, ty, body_id)
             }
             ItemKind::Fn(box Fn {
                 sig: FnSig { decl, header, span: fn_sig_span },
@@ -304,7 +304,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                         ),
                     },
                 );
-                hir::ItemKind::TyAlias(ident, ty, generics)
+                hir::ItemKind::TyAlias(ident, generics, ty)
             }
             ItemKind::Enum(ident, generics, enum_definition) => {
                 let ident = self.lower_ident(*ident);
@@ -318,7 +318,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                         )
                     },
                 );
-                hir::ItemKind::Enum(ident, hir::EnumDef { variants }, generics)
+                hir::ItemKind::Enum(ident, generics, hir::EnumDef { variants })
             }
             ItemKind::Struct(ident, generics, struct_def) => {
                 let ident = self.lower_ident(*ident);
@@ -328,7 +328,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     ImplTraitContext::Disallowed(ImplTraitPosition::Generic),
                     |this| this.lower_variant_data(hir_id, struct_def),
                 );
-                hir::ItemKind::Struct(ident, struct_def, generics)
+                hir::ItemKind::Struct(ident, generics, struct_def)
             }
             ItemKind::Union(ident, generics, vdata) => {
                 let ident = self.lower_ident(*ident);
@@ -338,7 +338,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     ImplTraitContext::Disallowed(ImplTraitPosition::Generic),
                     |this| this.lower_variant_data(hir_id, vdata),
                 );
-                hir::ItemKind::Union(ident, vdata, generics)
+                hir::ItemKind::Union(ident, generics, vdata)
             }
             ItemKind::Impl(box Impl {
                 safety,
@@ -467,8 +467,8 @@ impl<'hir> LoweringContext<'_, 'hir> {
             ItemKind::Delegation(box delegation) => {
                 let delegation_results = self.lower_delegation(delegation, id, false);
                 hir::ItemKind::Fn {
-                    ident: delegation_results.ident,
                     sig: delegation_results.sig,
+                    ident: delegation_results.ident,
                     generics: delegation_results.generics,
                     body: delegation_results.body_id,
                     has_body: true,
diff --git a/compiler/rustc_borrowck/src/lib.rs b/compiler/rustc_borrowck/src/lib.rs
index 676cb618b725..2bd0ffd143be 100644
--- a/compiler/rustc_borrowck/src/lib.rs
+++ b/compiler/rustc_borrowck/src/lib.rs
@@ -40,9 +40,7 @@ use rustc_middle::ty::{
     self, ParamEnv, RegionVid, Ty, TyCtxt, TypeFoldable, TypeVisitable, TypingMode, fold_regions,
 };
 use rustc_middle::{bug, span_bug};
-use rustc_mir_dataflow::impls::{
-    EverInitializedPlaces, MaybeInitializedPlaces, MaybeUninitializedPlaces,
-};
+use rustc_mir_dataflow::impls::{EverInitializedPlaces, MaybeUninitializedPlaces};
 use rustc_mir_dataflow::move_paths::{
     InitIndex, InitLocation, LookupResult, MoveData, MovePathIndex,
 };
@@ -324,10 +322,6 @@ fn do_mir_borrowck<'tcx>(
 
     let move_data = MoveData::gather_moves(body, tcx, |_| true);
 
-    let flow_inits = MaybeInitializedPlaces::new(tcx, body, &move_data)
-        .iterate_to_fixpoint(tcx, body, Some("borrowck"))
-        .into_results_cursor(body);
-
     let locals_are_invalidated_at_exit = tcx.hir_body_owner_kind(def).is_fn_or_closure();
     let borrow_set = BorrowSet::build(tcx, body, locals_are_invalidated_at_exit, &move_data);
 
@@ -346,7 +340,6 @@ fn do_mir_borrowck<'tcx>(
         body,
         &promoted,
         &location_table,
-        flow_inits,
         &move_data,
         &borrow_set,
         consumer_options,
diff --git a/compiler/rustc_borrowck/src/nll.rs b/compiler/rustc_borrowck/src/nll.rs
index fe899bb054fa..8664e99cae36 100644
--- a/compiler/rustc_borrowck/src/nll.rs
+++ b/compiler/rustc_borrowck/src/nll.rs
@@ -11,8 +11,6 @@ use rustc_middle::mir::pretty::{PrettyPrintMirOptions, dump_mir_with_options};
 use rustc_middle::mir::{Body, PassWhere, Promoted, create_dump_file, dump_enabled, dump_mir};
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::{self, TyCtxt};
-use rustc_mir_dataflow::ResultsCursor;
-use rustc_mir_dataflow::impls::MaybeInitializedPlaces;
 use rustc_mir_dataflow::move_paths::MoveData;
 use rustc_mir_dataflow::points::DenseLocationMap;
 use rustc_session::config::MirIncludeSpans;
@@ -75,14 +73,13 @@ pub(crate) fn replace_regions_in_mir<'tcx>(
 /// Computes the (non-lexical) regions from the input MIR.
 ///
 /// This may result in errors being reported.
-pub(crate) fn compute_regions<'a, 'tcx>(
+pub(crate) fn compute_regions<'tcx>(
     root_cx: &mut BorrowCheckRootCtxt<'tcx>,
     infcx: &BorrowckInferCtxt<'tcx>,
     universal_regions: UniversalRegions<'tcx>,
     body: &Body<'tcx>,
     promoted: &IndexSlice<Promoted, Body<'tcx>>,
     location_table: &PoloniusLocationTable,
-    flow_inits: ResultsCursor<'a, 'tcx, MaybeInitializedPlaces<'a, 'tcx>>,
     move_data: &MoveData<'tcx>,
     borrow_set: &BorrowSet<'tcx>,
     consumer_options: Option<ConsumerOptions>,
@@ -112,7 +109,6 @@ pub(crate) fn compute_regions<'a, 'tcx>(
         location_table,
         borrow_set,
         &mut polonius_facts,
-        flow_inits,
         move_data,
         Rc::clone(&location_map),
     );
diff --git a/compiler/rustc_borrowck/src/type_check/liveness/mod.rs b/compiler/rustc_borrowck/src/type_check/liveness/mod.rs
index b7a21cf48c8f..ca1b850f7665 100644
--- a/compiler/rustc_borrowck/src/type_check/liveness/mod.rs
+++ b/compiler/rustc_borrowck/src/type_check/liveness/mod.rs
@@ -5,8 +5,6 @@ use rustc_middle::mir::{Body, Local, Location, SourceInfo};
 use rustc_middle::span_bug;
 use rustc_middle::ty::relate::Relate;
 use rustc_middle::ty::{GenericArgsRef, Region, RegionVid, Ty, TyCtxt, TypeVisitable};
-use rustc_mir_dataflow::ResultsCursor;
-use rustc_mir_dataflow::impls::MaybeInitializedPlaces;
 use rustc_mir_dataflow::move_paths::MoveData;
 use rustc_mir_dataflow::points::DenseLocationMap;
 use tracing::debug;
@@ -28,10 +26,9 @@ mod trace;
 ///
 /// N.B., this computation requires normalization; therefore, it must be
 /// performed before
-pub(super) fn generate<'a, 'tcx>(
+pub(super) fn generate<'tcx>(
     typeck: &mut TypeChecker<'_, 'tcx>,
     location_map: &DenseLocationMap,
-    flow_inits: ResultsCursor<'a, 'tcx, MaybeInitializedPlaces<'a, 'tcx>>,
     move_data: &MoveData<'tcx>,
 ) {
     debug!("liveness::generate");
@@ -58,7 +55,7 @@ pub(super) fn generate<'a, 'tcx>(
     let (relevant_live_locals, boring_locals) =
         compute_relevant_live_locals(typeck.tcx(), &free_regions, typeck.body);
 
-    trace::trace(typeck, location_map, flow_inits, move_data, relevant_live_locals, boring_locals);
+    trace::trace(typeck, location_map, move_data, relevant_live_locals, boring_locals);
 
     // Mark regions that should be live where they appear within rvalues or within a call: like
     // args, regions, and types.
diff --git a/compiler/rustc_borrowck/src/type_check/liveness/trace.rs b/compiler/rustc_borrowck/src/type_check/liveness/trace.rs
index 512288a0f7d8..5d30fa71e92c 100644
--- a/compiler/rustc_borrowck/src/type_check/liveness/trace.rs
+++ b/compiler/rustc_borrowck/src/type_check/liveness/trace.rs
@@ -7,10 +7,10 @@ use rustc_middle::mir::{BasicBlock, Body, ConstraintCategory, HasLocalDecls, Loc
 use rustc_middle::traits::query::DropckOutlivesResult;
 use rustc_middle::ty::relate::Relate;
 use rustc_middle::ty::{Ty, TyCtxt, TypeVisitable, TypeVisitableExt};
-use rustc_mir_dataflow::ResultsCursor;
 use rustc_mir_dataflow::impls::MaybeInitializedPlaces;
 use rustc_mir_dataflow::move_paths::{HasMoveData, MoveData, MovePathIndex};
 use rustc_mir_dataflow::points::{DenseLocationMap, PointIndex};
+use rustc_mir_dataflow::{Analysis, ResultsCursor};
 use rustc_span::{DUMMY_SP, ErrorGuaranteed, Span};
 use rustc_trait_selection::error_reporting::InferCtxtErrorExt;
 use rustc_trait_selection::traits::ObligationCtxt;
@@ -37,10 +37,9 @@ use crate::type_check::{NormalizeLocation, TypeChecker};
 /// DROP-LIVE set are to the liveness sets for regions found in the
 /// `dropck_outlives` result of the variable's type (in particular,
 /// this respects `#[may_dangle]` annotations).
-pub(super) fn trace<'a, 'tcx>(
+pub(super) fn trace<'tcx>(
     typeck: &mut TypeChecker<'_, 'tcx>,
     location_map: &DenseLocationMap,
-    flow_inits: ResultsCursor<'a, 'tcx, MaybeInitializedPlaces<'a, 'tcx>>,
     move_data: &MoveData<'tcx>,
     relevant_live_locals: Vec<Local>,
     boring_locals: Vec<Local>,
@@ -48,7 +47,7 @@ pub(super) fn trace<'a, 'tcx>(
     let local_use_map = &LocalUseMap::build(&relevant_live_locals, location_map, typeck.body);
     let cx = LivenessContext {
         typeck,
-        flow_inits,
+        flow_inits: None,
         location_map,
         local_use_map,
         move_data,
@@ -65,7 +64,7 @@ pub(super) fn trace<'a, 'tcx>(
 }
 
 /// Contextual state for the type-liveness coroutine.
-struct LivenessContext<'a, 'typeck, 'b, 'tcx> {
+struct LivenessContext<'a, 'typeck, 'tcx> {
     /// Current type-checker, giving us our inference context etc.
     ///
     /// This also stores the body we're currently analyzing.
@@ -81,8 +80,8 @@ struct LivenessContext<'a, 'typeck, 'b, 'tcx> {
     drop_data: FxIndexMap<Ty<'tcx>, DropData<'tcx>>,
 
     /// Results of dataflow tracking which variables (and paths) have been
-    /// initialized.
-    flow_inits: ResultsCursor<'b, 'tcx, MaybeInitializedPlaces<'b, 'tcx>>,
+    /// initialized. Computed lazily when needed by drop-liveness.
+    flow_inits: Option<ResultsCursor<'a, 'tcx, MaybeInitializedPlaces<'a, 'tcx>>>,
 
     /// Index indicating where each variable is assigned, used, or
     /// dropped.
@@ -94,8 +93,8 @@ struct DropData<'tcx> {
     region_constraint_data: Option<&'tcx QueryRegionConstraints<'tcx>>,
 }
 
-struct LivenessResults<'a, 'typeck, 'b, 'tcx> {
-    cx: LivenessContext<'a, 'typeck, 'b, 'tcx>,
+struct LivenessResults<'a, 'typeck, 'tcx> {
+    cx: LivenessContext<'a, 'typeck, 'tcx>,
 
     /// Set of points that define the current local.
     defs: DenseBitSet<PointIndex>,
@@ -116,8 +115,8 @@ struct LivenessResults<'a, 'typeck, 'b, 'tcx> {
     stack: Vec<PointIndex>,
 }
 
-impl<'a, 'typeck, 'b, 'tcx> LivenessResults<'a, 'typeck, 'b, 'tcx> {
-    fn new(cx: LivenessContext<'a, 'typeck, 'b, 'tcx>) -> Self {
+impl<'a, 'typeck, 'tcx> LivenessResults<'a, 'typeck, 'tcx> {
+    fn new(cx: LivenessContext<'a, 'typeck, 'tcx>) -> Self {
         let num_points = cx.location_map.num_points();
         LivenessResults {
             cx,
@@ -459,20 +458,56 @@ impl<'a, 'typeck, 'b, 'tcx> LivenessResults<'a, 'typeck, 'b, 'tcx> {
     }
 }
 
-impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> {
+impl<'a, 'typeck, 'tcx> LivenessContext<'a, 'typeck, 'tcx> {
+    /// Computes the `MaybeInitializedPlaces` dataflow analysis if it hasn't been done already.
+    ///
+    /// In practice, the results of this dataflow analysis are rarely needed but can be expensive to
+    /// compute on big functions, so we compute them lazily as a fast path when:
+    /// - there are relevant live locals
+    /// - there are drop points for these relevant live locals.
+    ///
+    /// This happens as part of the drop-liveness computation: it's the only place checking for
+    /// maybe-initializedness of `MovePathIndex`es.
+    fn flow_inits(&mut self) -> &mut ResultsCursor<'a, 'tcx, MaybeInitializedPlaces<'a, 'tcx>> {
+        self.flow_inits.get_or_insert_with(|| {
+            let tcx = self.typeck.tcx();
+            let body = self.typeck.body;
+            // FIXME: reduce the `MaybeInitializedPlaces` domain to the useful `MovePath`s.
+            //
+            // This dataflow analysis computes maybe-initializedness of all move paths, which
+            // explains why it can be expensive on big functions. But this data is only used in
+            // drop-liveness. Therefore, most of the move paths computed here are ultimately unused,
+            // even if the results are computed lazily and "no relevant live locals with drop
+            // points" is the common case.
+            //
+            // So we only need the ones for 1) relevant live locals 2) that have drop points. That's
+            // a much, much smaller domain: in our benchmarks, when it's not zero (the most likely
+            // case), there are a few dozens compared to e.g. thousands or tens of thousands of
+            // locals and move paths.
+            let flow_inits = MaybeInitializedPlaces::new(tcx, body, self.move_data)
+                .iterate_to_fixpoint(tcx, body, Some("borrowck"))
+                .into_results_cursor(body);
+            flow_inits
+        })
+    }
+}
+
+impl<'tcx> LivenessContext<'_, '_, 'tcx> {
     fn body(&self) -> &Body<'tcx> {
         self.typeck.body
     }
+
     /// Returns `true` if the local variable (or some part of it) is initialized at the current
     /// cursor position. Callers should call one of the `seek` methods immediately before to point
     /// the cursor to the desired location.
-    fn initialized_at_curr_loc(&self, mpi: MovePathIndex) -> bool {
-        let state = self.flow_inits.get();
+    fn initialized_at_curr_loc(&mut self, mpi: MovePathIndex) -> bool {
+        let flow_inits = self.flow_inits();
+        let state = flow_inits.get();
         if state.contains(mpi) {
             return true;
         }
 
-        let move_paths = &self.flow_inits.analysis().move_data().move_paths;
+        let move_paths = &flow_inits.analysis().move_data().move_paths;
         move_paths[mpi].find_descendant(move_paths, |mpi| state.contains(mpi)).is_some()
     }
 
@@ -481,7 +516,8 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> {
     /// DROP of some local variable will have an effect -- note that
     /// drops, as they may unwind, are always terminators.
     fn initialized_at_terminator(&mut self, block: BasicBlock, mpi: MovePathIndex) -> bool {
-        self.flow_inits.seek_before_primary_effect(self.body().terminator_loc(block));
+        let terminator_location = self.body().terminator_loc(block);
+        self.flow_inits().seek_before_primary_effect(terminator_location);
         self.initialized_at_curr_loc(mpi)
     }
 
@@ -491,7 +527,8 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> {
     /// **Warning:** Does not account for the result of `Call`
     /// instructions.
     fn initialized_at_exit(&mut self, block: BasicBlock, mpi: MovePathIndex) -> bool {
-        self.flow_inits.seek_after_primary_effect(self.body().terminator_loc(block));
+        let terminator_location = self.body().terminator_loc(block);
+        self.flow_inits().seek_after_primary_effect(terminator_location);
         self.initialized_at_curr_loc(mpi)
     }
 
diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs
index 3c95ebf9ffab..4f5baeff7c32 100644
--- a/compiler/rustc_borrowck/src/type_check/mod.rs
+++ b/compiler/rustc_borrowck/src/type_check/mod.rs
@@ -30,8 +30,6 @@ use rustc_middle::ty::{
     TypeVisitableExt, UserArgs, UserTypeAnnotationIndex, fold_regions,
 };
 use rustc_middle::{bug, span_bug};
-use rustc_mir_dataflow::ResultsCursor;
-use rustc_mir_dataflow::impls::MaybeInitializedPlaces;
 use rustc_mir_dataflow::move_paths::MoveData;
 use rustc_mir_dataflow::points::DenseLocationMap;
 use rustc_span::def_id::CRATE_DEF_ID;
@@ -97,10 +95,9 @@ mod relate_tys;
 /// - `location_table` -- for datalog polonius, the map between `Location`s and `RichLocation`s
 /// - `borrow_set` -- information about borrows occurring in `body`
 /// - `polonius_facts` -- when using Polonius, this is the generated set of Polonius facts
-/// - `flow_inits` -- results of a maybe-init dataflow analysis
 /// - `move_data` -- move-data constructed when performing the maybe-init dataflow analysis
 /// - `location_map` -- map between MIR `Location` and `PointIndex`
-pub(crate) fn type_check<'a, 'tcx>(
+pub(crate) fn type_check<'tcx>(
     root_cx: &mut BorrowCheckRootCtxt<'tcx>,
     infcx: &BorrowckInferCtxt<'tcx>,
     body: &Body<'tcx>,
@@ -109,7 +106,6 @@ pub(crate) fn type_check<'a, 'tcx>(
     location_table: &PoloniusLocationTable,
     borrow_set: &BorrowSet<'tcx>,
     polonius_facts: &mut Option<PoloniusFacts>,
-    flow_inits: ResultsCursor<'a, 'tcx, MaybeInitializedPlaces<'a, 'tcx>>,
     move_data: &MoveData<'tcx>,
     location_map: Rc<DenseLocationMap>,
 ) -> MirTypeckResults<'tcx> {
@@ -167,7 +163,7 @@ pub(crate) fn type_check<'a, 'tcx>(
     typeck.equate_inputs_and_outputs(&normalized_inputs_and_output);
     typeck.check_signature_annotation();
 
-    liveness::generate(&mut typeck, &location_map, flow_inits, move_data);
+    liveness::generate(&mut typeck, &location_map, move_data);
 
     let opaque_type_values =
         opaque_types::take_opaques_and_register_member_constraints(&mut typeck);
diff --git a/compiler/rustc_const_eval/src/interpret/intrinsics.rs b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
index bf4152d4b8cd..64467a901369 100644
--- a/compiler/rustc_const_eval/src/interpret/intrinsics.rs
+++ b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
@@ -518,6 +518,103 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             sym::fabsf64 => self.float_abs_intrinsic::<Double>(args, dest)?,
             sym::fabsf128 => self.float_abs_intrinsic::<Quad>(args, dest)?,
 
+            sym::floorf16 => self.float_round_intrinsic::<Half>(
+                args,
+                dest,
+                rustc_apfloat::Round::TowardNegative,
+            )?,
+            sym::floorf32 => self.float_round_intrinsic::<Single>(
+                args,
+                dest,
+                rustc_apfloat::Round::TowardNegative,
+            )?,
+            sym::floorf64 => self.float_round_intrinsic::<Double>(
+                args,
+                dest,
+                rustc_apfloat::Round::TowardNegative,
+            )?,
+            sym::floorf128 => self.float_round_intrinsic::<Quad>(
+                args,
+                dest,
+                rustc_apfloat::Round::TowardNegative,
+            )?,
+
+            sym::ceilf16 => self.float_round_intrinsic::<Half>(
+                args,
+                dest,
+                rustc_apfloat::Round::TowardPositive,
+            )?,
+            sym::ceilf32 => self.float_round_intrinsic::<Single>(
+                args,
+                dest,
+                rustc_apfloat::Round::TowardPositive,
+            )?,
+            sym::ceilf64 => self.float_round_intrinsic::<Double>(
+                args,
+                dest,
+                rustc_apfloat::Round::TowardPositive,
+            )?,
+            sym::ceilf128 => self.float_round_intrinsic::<Quad>(
+                args,
+                dest,
+                rustc_apfloat::Round::TowardPositive,
+            )?,
+
+            sym::truncf16 => {
+                self.float_round_intrinsic::<Half>(args, dest, rustc_apfloat::Round::TowardZero)?
+            }
+            sym::truncf32 => {
+                self.float_round_intrinsic::<Single>(args, dest, rustc_apfloat::Round::TowardZero)?
+            }
+            sym::truncf64 => {
+                self.float_round_intrinsic::<Double>(args, dest, rustc_apfloat::Round::TowardZero)?
+            }
+            sym::truncf128 => {
+                self.float_round_intrinsic::<Quad>(args, dest, rustc_apfloat::Round::TowardZero)?
+            }
+
+            sym::roundf16 => self.float_round_intrinsic::<Half>(
+                args,
+                dest,
+                rustc_apfloat::Round::NearestTiesToAway,
+            )?,
+            sym::roundf32 => self.float_round_intrinsic::<Single>(
+                args,
+                dest,
+                rustc_apfloat::Round::NearestTiesToAway,
+            )?,
+            sym::roundf64 => self.float_round_intrinsic::<Double>(
+                args,
+                dest,
+                rustc_apfloat::Round::NearestTiesToAway,
+            )?,
+            sym::roundf128 => self.float_round_intrinsic::<Quad>(
+                args,
+                dest,
+                rustc_apfloat::Round::NearestTiesToAway,
+            )?,
+
+            sym::round_ties_even_f16 => self.float_round_intrinsic::<Half>(
+                args,
+                dest,
+                rustc_apfloat::Round::NearestTiesToEven,
+            )?,
+            sym::round_ties_even_f32 => self.float_round_intrinsic::<Single>(
+                args,
+                dest,
+                rustc_apfloat::Round::NearestTiesToEven,
+            )?,
+            sym::round_ties_even_f64 => self.float_round_intrinsic::<Double>(
+                args,
+                dest,
+                rustc_apfloat::Round::NearestTiesToEven,
+            )?,
+            sym::round_ties_even_f128 => self.float_round_intrinsic::<Quad>(
+                args,
+                dest,
+                rustc_apfloat::Round::NearestTiesToEven,
+            )?,
+
             // Unsupported intrinsic: skip the return_to_block below.
             _ => return interp_ok(false),
         }
@@ -900,4 +997,20 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         self.write_scalar(x.abs(), dest)?;
         interp_ok(())
     }
+
+    fn float_round_intrinsic<F>(
+        &mut self,
+        args: &[OpTy<'tcx, M::Provenance>],
+        dest: &PlaceTy<'tcx, M::Provenance>,
+        mode: rustc_apfloat::Round,
+    ) -> InterpResult<'tcx, ()>
+    where
+        F: rustc_apfloat::Float + rustc_apfloat::FloatConvert<F> + Into<Scalar<M::Provenance>>,
+    {
+        let x: F = self.read_scalar(&args[0])?.to_float()?;
+        let res = x.round_to_integral(mode).value;
+        let res = self.adjust_nan(res, &[x]);
+        self.write_scalar(res, dest)?;
+        interp_ok(())
+    }
 }
diff --git a/compiler/rustc_driver_impl/src/lib.rs b/compiler/rustc_driver_impl/src/lib.rs
index 056c476d5e12..54a331a49044 100644
--- a/compiler/rustc_driver_impl/src/lib.rs
+++ b/compiler/rustc_driver_impl/src/lib.rs
@@ -12,7 +12,6 @@
 #![feature(decl_macro)]
 #![feature(panic_backtrace_config)]
 #![feature(panic_update_hook)]
-#![feature(result_flattening)]
 #![feature(rustdoc_internals)]
 #![feature(try_blocks)]
 // tidy-alphabetical-end
diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs
index f63ab3036891..b4fcc16c09c8 100644
--- a/compiler/rustc_hir/src/hir.rs
+++ b/compiler/rustc_hir/src/hir.rs
@@ -4106,11 +4106,11 @@ impl<'hir> Item<'hir> {
 
         expect_use, (&'hir UsePath<'hir>, UseKind), ItemKind::Use(p, uk), (p, *uk);
 
-        expect_static, (Ident, &'hir Ty<'hir>, Mutability, BodyId),
-            ItemKind::Static(ident, ty, mutbl, body), (*ident, ty, *mutbl, *body);
+        expect_static, (Mutability, Ident, &'hir Ty<'hir>, BodyId),
+            ItemKind::Static(mutbl, ident, ty, body), (*mutbl, *ident, ty, *body);
 
-        expect_const, (Ident, &'hir Ty<'hir>, &'hir Generics<'hir>, BodyId),
-            ItemKind::Const(ident, ty, generics, body), (*ident, ty, generics, *body);
+        expect_const, (Ident, &'hir Generics<'hir>, &'hir Ty<'hir>, BodyId),
+            ItemKind::Const(ident, generics, ty, body), (*ident, generics, ty, *body);
 
         expect_fn, (Ident, &FnSig<'hir>, &'hir Generics<'hir>, BodyId),
             ItemKind::Fn { ident, sig, generics, body, .. }, (*ident, sig, generics, *body);
@@ -4125,17 +4125,17 @@ impl<'hir> Item<'hir> {
 
         expect_global_asm, &'hir InlineAsm<'hir>, ItemKind::GlobalAsm { asm, .. }, asm;
 
-        expect_ty_alias, (Ident, &'hir Ty<'hir>, &'hir Generics<'hir>),
-            ItemKind::TyAlias(ident, ty, generics), (*ident, ty, generics);
+        expect_ty_alias, (Ident, &'hir Generics<'hir>, &'hir Ty<'hir>),
+            ItemKind::TyAlias(ident, generics, ty), (*ident, generics, ty);
 
-        expect_enum, (Ident, &EnumDef<'hir>, &'hir Generics<'hir>),
-            ItemKind::Enum(ident, def, generics), (*ident, def, generics);
+        expect_enum, (Ident, &'hir Generics<'hir>, &EnumDef<'hir>),
+            ItemKind::Enum(ident, generics, def), (*ident, generics, def);
 
-        expect_struct, (Ident, &VariantData<'hir>, &'hir Generics<'hir>),
-            ItemKind::Struct(ident, data, generics), (*ident, data, generics);
+        expect_struct, (Ident, &'hir Generics<'hir>, &VariantData<'hir>),
+            ItemKind::Struct(ident, generics, data), (*ident, generics, data);
 
-        expect_union, (Ident, &VariantData<'hir>, &'hir Generics<'hir>),
-            ItemKind::Union(ident, data, generics), (*ident, data, generics);
+        expect_union, (Ident, &'hir Generics<'hir>, &VariantData<'hir>),
+            ItemKind::Union(ident, generics, data), (*ident, generics, data);
 
         expect_trait,
             (
@@ -4278,13 +4278,13 @@ pub enum ItemKind<'hir> {
     Use(&'hir UsePath<'hir>, UseKind),
 
     /// A `static` item.
-    Static(Ident, &'hir Ty<'hir>, Mutability, BodyId),
+    Static(Mutability, Ident, &'hir Ty<'hir>, BodyId),
     /// A `const` item.
-    Const(Ident, &'hir Ty<'hir>, &'hir Generics<'hir>, BodyId),
+    Const(Ident, &'hir Generics<'hir>, &'hir Ty<'hir>, BodyId),
     /// A function declaration.
     Fn {
-        ident: Ident,
         sig: FnSig<'hir>,
+        ident: Ident,
         generics: &'hir Generics<'hir>,
         body: BodyId,
         /// Whether this function actually has a body.
@@ -4309,13 +4309,13 @@ pub enum ItemKind<'hir> {
         fake_body: BodyId,
     },
     /// A type alias, e.g., `type Foo = Bar<u8>`.
-    TyAlias(Ident, &'hir Ty<'hir>, &'hir Generics<'hir>),
+    TyAlias(Ident, &'hir Generics<'hir>, &'hir Ty<'hir>),
     /// An enum definition, e.g., `enum Foo<A, B> { C<A>, D<B> }`.
-    Enum(Ident, EnumDef<'hir>, &'hir Generics<'hir>),
+    Enum(Ident, &'hir Generics<'hir>, EnumDef<'hir>),
     /// A struct definition, e.g., `struct Foo<A> {x: A}`.
-    Struct(Ident, VariantData<'hir>, &'hir Generics<'hir>),
+    Struct(Ident, &'hir Generics<'hir>, VariantData<'hir>),
     /// A union definition, e.g., `union Foo<A, B> {x: A, y: B}`.
-    Union(Ident, VariantData<'hir>, &'hir Generics<'hir>),
+    Union(Ident, &'hir Generics<'hir>, VariantData<'hir>),
     /// A trait definition.
     Trait(IsAuto, Safety, Ident, &'hir Generics<'hir>, GenericBounds<'hir>, &'hir [TraitItemRef]),
     /// A trait alias.
@@ -4352,7 +4352,7 @@ impl ItemKind<'_> {
         match *self {
             ItemKind::ExternCrate(_, ident)
             | ItemKind::Use(_, UseKind::Single(ident))
-            | ItemKind::Static(ident, ..)
+            | ItemKind::Static(_, ident, ..)
             | ItemKind::Const(ident, ..)
             | ItemKind::Fn { ident, .. }
             | ItemKind::Macro(ident, ..)
@@ -4374,11 +4374,11 @@ impl ItemKind<'_> {
     pub fn generics(&self) -> Option<&Generics<'_>> {
         Some(match self {
             ItemKind::Fn { generics, .. }
-            | ItemKind::TyAlias(_, _, generics)
-            | ItemKind::Const(_, _, generics, _)
-            | ItemKind::Enum(_, _, generics)
-            | ItemKind::Struct(_, _, generics)
-            | ItemKind::Union(_, _, generics)
+            | ItemKind::TyAlias(_, generics, _)
+            | ItemKind::Const(_, generics, _, _)
+            | ItemKind::Enum(_, generics, _)
+            | ItemKind::Struct(_, generics, _)
+            | ItemKind::Union(_, generics, _)
             | ItemKind::Trait(_, _, _, generics, _, _)
             | ItemKind::TraitAlias(_, generics, _)
             | ItemKind::Impl(Impl { generics, .. }) => generics,
@@ -4802,9 +4802,9 @@ impl<'hir> Node<'hir> {
     pub fn ty(self) -> Option<&'hir Ty<'hir>> {
         match self {
             Node::Item(it) => match it.kind {
-                ItemKind::TyAlias(_, ty, _)
-                | ItemKind::Static(_, ty, _, _)
-                | ItemKind::Const(_, ty, _, _) => Some(ty),
+                ItemKind::TyAlias(_, _, ty)
+                | ItemKind::Static(_, _, ty, _)
+                | ItemKind::Const(_, _, ty, _) => Some(ty),
                 ItemKind::Impl(impl_item) => Some(&impl_item.self_ty),
                 _ => None,
             },
@@ -4824,7 +4824,7 @@ impl<'hir> Node<'hir> {
 
     pub fn alias_ty(self) -> Option<&'hir Ty<'hir>> {
         match self {
-            Node::Item(Item { kind: ItemKind::TyAlias(_, ty, _), .. }) => Some(ty),
+            Node::Item(Item { kind: ItemKind::TyAlias(_, _, ty), .. }) => Some(ty),
             _ => None,
         }
     }
diff --git a/compiler/rustc_hir/src/intravisit.rs b/compiler/rustc_hir/src/intravisit.rs
index a60de4b1fc31..1fd44e44b9ce 100644
--- a/compiler/rustc_hir/src/intravisit.rs
+++ b/compiler/rustc_hir/src/intravisit.rs
@@ -545,15 +545,15 @@ pub fn walk_item<'v, V: Visitor<'v>>(visitor: &mut V, item: &'v Item<'v>) -> V::
                 UseKind::Glob | UseKind::ListStem => {}
             }
         }
-        ItemKind::Static(ident, ref typ, _, body) => {
+        ItemKind::Static(_, ident, ref typ, body) => {
             try_visit!(visitor.visit_ident(ident));
             try_visit!(visitor.visit_ty_unambig(typ));
             try_visit!(visitor.visit_nested_body(body));
         }
-        ItemKind::Const(ident, ref typ, ref generics, body) => {
+        ItemKind::Const(ident, ref generics, ref typ, body) => {
             try_visit!(visitor.visit_ident(ident));
-            try_visit!(visitor.visit_ty_unambig(typ));
             try_visit!(visitor.visit_generics(generics));
+            try_visit!(visitor.visit_ty_unambig(typ));
             try_visit!(visitor.visit_nested_body(body));
         }
         ItemKind::Fn { ident, sig, generics, body: body_id, .. } => {
@@ -583,12 +583,12 @@ pub fn walk_item<'v, V: Visitor<'v>>(visitor: &mut V, item: &'v Item<'v>) -> V::
             // typeck results set correctly.
             try_visit!(visitor.visit_nested_body(fake_body));
         }
-        ItemKind::TyAlias(ident, ref ty, ref generics) => {
+        ItemKind::TyAlias(ident, ref generics, ref ty) => {
             try_visit!(visitor.visit_ident(ident));
-            try_visit!(visitor.visit_ty_unambig(ty));
             try_visit!(visitor.visit_generics(generics));
+            try_visit!(visitor.visit_ty_unambig(ty));
         }
-        ItemKind::Enum(ident, ref enum_definition, ref generics) => {
+        ItemKind::Enum(ident, ref generics, ref enum_definition) => {
             try_visit!(visitor.visit_ident(ident));
             try_visit!(visitor.visit_generics(generics));
             try_visit!(visitor.visit_enum_def(enum_definition));
@@ -609,8 +609,8 @@ pub fn walk_item<'v, V: Visitor<'v>>(visitor: &mut V, item: &'v Item<'v>) -> V::
             try_visit!(visitor.visit_ty_unambig(self_ty));
             walk_list!(visitor, visit_impl_item_ref, *items);
         }
-        ItemKind::Struct(ident, ref struct_definition, ref generics)
-        | ItemKind::Union(ident, ref struct_definition, ref generics) => {
+        ItemKind::Struct(ident, ref generics, ref struct_definition)
+        | ItemKind::Union(ident, ref generics, ref struct_definition) => {
             try_visit!(visitor.visit_ident(ident));
             try_visit!(visitor.visit_generics(generics));
             try_visit!(visitor.visit_variant_data(struct_definition));
diff --git a/compiler/rustc_hir_analysis/src/check/intrinsic.rs b/compiler/rustc_hir_analysis/src/check/intrinsic.rs
index 54bb3ac41130..09610a2f3ec6 100644
--- a/compiler/rustc_hir_analysis/src/check/intrinsic.rs
+++ b/compiler/rustc_hir_analysis/src/check/intrinsic.rs
@@ -265,6 +265,7 @@ pub(crate) fn check_intrinsic_type(
                 vec![Ty::new_imm_ptr(tcx, param(0)), tcx.types.isize],
                 Ty::new_imm_ptr(tcx, param(0)),
             ),
+            sym::slice_get_unchecked => (3, 0, vec![param(1), tcx.types.usize], param(0)),
             sym::ptr_mask => (
                 1,
                 0,
diff --git a/compiler/rustc_hir_analysis/src/check/wfcheck.rs b/compiler/rustc_hir_analysis/src/check/wfcheck.rs
index f85ff5a6f4be..b764b714fe17 100644
--- a/compiler/rustc_hir_analysis/src/check/wfcheck.rs
+++ b/compiler/rustc_hir_analysis/src/check/wfcheck.rs
@@ -297,32 +297,30 @@ fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) -> Result<()
         hir::ItemKind::Fn { ident, sig, .. } => {
             check_item_fn(tcx, def_id, ident, item.span, sig.decl)
         }
-        hir::ItemKind::Static(_, ty, ..) => {
+        hir::ItemKind::Static(_, _, ty, _) => {
             check_static_item(tcx, def_id, ty.span, UnsizedHandling::Forbid)
         }
-        hir::ItemKind::Const(_, ty, ..) => check_const_item(tcx, def_id, ty.span, item.span),
-        hir::ItemKind::Struct(_, _, hir_generics) => {
+        hir::ItemKind::Const(_, _, ty, _) => check_const_item(tcx, def_id, ty.span, item.span),
+        hir::ItemKind::Struct(_, generics, _) => {
             let res = check_type_defn(tcx, item, false);
-            check_variances_for_type_defn(tcx, item, hir_generics);
+            check_variances_for_type_defn(tcx, item, generics);
             res
         }
-        hir::ItemKind::Union(_, _, hir_generics) => {
+        hir::ItemKind::Union(_, generics, _) => {
             let res = check_type_defn(tcx, item, true);
-            check_variances_for_type_defn(tcx, item, hir_generics);
+            check_variances_for_type_defn(tcx, item, generics);
             res
         }
-        hir::ItemKind::Enum(_, _, hir_generics) => {
+        hir::ItemKind::Enum(_, generics, _) => {
             let res = check_type_defn(tcx, item, true);
-            check_variances_for_type_defn(tcx, item, hir_generics);
+            check_variances_for_type_defn(tcx, item, generics);
             res
         }
         hir::ItemKind::Trait(..) => check_trait(tcx, item),
         hir::ItemKind::TraitAlias(..) => check_trait(tcx, item),
         // `ForeignItem`s are handled separately.
         hir::ItemKind::ForeignMod { .. } => Ok(()),
-        hir::ItemKind::TyAlias(_, hir_ty, hir_generics)
-            if tcx.type_alias_is_lazy(item.owner_id) =>
-        {
+        hir::ItemKind::TyAlias(_, generics, hir_ty) if tcx.type_alias_is_lazy(item.owner_id) => {
             let res = enter_wf_checking_ctxt(tcx, item.span, def_id, |wfcx| {
                 let ty = tcx.type_of(def_id).instantiate_identity();
                 let item_ty =
@@ -335,7 +333,7 @@ fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) -> Result<()
                 check_where_clauses(wfcx, item.span, def_id);
                 Ok(())
             });
-            check_variances_for_type_defn(tcx, item, hir_generics);
+            check_variances_for_type_defn(tcx, item, generics);
             res
         }
         _ => Ok(()),
diff --git a/compiler/rustc_hir_analysis/src/collect.rs b/compiler/rustc_hir_analysis/src/collect.rs
index 8a2edd843f20..a649e7d67af3 100644
--- a/compiler/rustc_hir_analysis/src/collect.rs
+++ b/compiler/rustc_hir_analysis/src/collect.rs
@@ -248,13 +248,13 @@ fn reject_placeholder_type_signatures_in_item<'tcx>(
     item: &'tcx hir::Item<'tcx>,
 ) {
     let (generics, suggest) = match &item.kind {
-        hir::ItemKind::Union(_, _, generics)
-        | hir::ItemKind::Enum(_, _, generics)
+        hir::ItemKind::Union(_, generics, _)
+        | hir::ItemKind::Enum(_, generics, _)
         | hir::ItemKind::TraitAlias(_, generics, _)
         | hir::ItemKind::Trait(_, _, _, generics, ..)
         | hir::ItemKind::Impl(hir::Impl { generics, .. })
-        | hir::ItemKind::Struct(_, _, generics) => (generics, true),
-        hir::ItemKind::TyAlias(_, _, generics) => (generics, false),
+        | hir::ItemKind::Struct(_, generics, _) => (generics, true),
+        hir::ItemKind::TyAlias(_, generics, _) => (generics, false),
         // `static`, `fn` and `const` are handled elsewhere to suggest appropriate type.
         _ => return,
     };
@@ -470,9 +470,9 @@ impl<'tcx> HirTyLowerer<'tcx> for ItemCtxt<'tcx> {
                         .tcx
                         .hir_expect_item(self.tcx.hir_get_parent_item(self.hir_id()).def_id);
                     match &item.kind {
-                        hir::ItemKind::Enum(_, _, generics)
-                        | hir::ItemKind::Struct(_, _, generics)
-                        | hir::ItemKind::Union(_, _, generics) => {
+                        hir::ItemKind::Enum(_, generics, _)
+                        | hir::ItemKind::Struct(_, generics, _)
+                        | hir::ItemKind::Union(_, generics, _) => {
                             let lt_name = get_new_lifetime_name(self.tcx, poly_trait_ref, generics);
                             let (lt_sp, sugg) = match generics.params {
                                 [] => (generics.span, format!("<{lt_name}>")),
@@ -740,7 +740,7 @@ fn lower_item(tcx: TyCtxt<'_>, item_id: hir::ItemId) {
             tcx.at(it.span).explicit_super_predicates_of(def_id);
             tcx.ensure_ok().predicates_of(def_id);
         }
-        hir::ItemKind::Struct(_, struct_def, _) | hir::ItemKind::Union(_, struct_def, _) => {
+        hir::ItemKind::Struct(_, _, struct_def) | hir::ItemKind::Union(_, _, struct_def) => {
             tcx.ensure_ok().generics_of(def_id);
             tcx.ensure_ok().type_of(def_id);
             tcx.ensure_ok().predicates_of(def_id);
@@ -762,7 +762,7 @@ fn lower_item(tcx: TyCtxt<'_>, item_id: hir::ItemId) {
             tcx.ensure_ok().predicates_of(def_id);
         }
 
-        hir::ItemKind::Static(_, ty, ..) | hir::ItemKind::Const(_, ty, ..) => {
+        hir::ItemKind::Static(_, _, ty, _) | hir::ItemKind::Const(_, _, ty, _) => {
             tcx.ensure_ok().generics_of(def_id);
             tcx.ensure_ok().type_of(def_id);
             tcx.ensure_ok().predicates_of(def_id);
@@ -1093,7 +1093,7 @@ fn adt_def(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::AdtDef<'_> {
 
     let repr = tcx.repr_options_of_def(def_id);
     let (kind, variants) = match &item.kind {
-        ItemKind::Enum(_, def, _) => {
+        ItemKind::Enum(_, _, def) => {
             let mut distance_from_explicit = 0;
             let variants = def
                 .variants
@@ -1121,7 +1121,7 @@ fn adt_def(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::AdtDef<'_> {
 
             (AdtKind::Enum, variants)
         }
-        ItemKind::Struct(ident, def, _) | ItemKind::Union(ident, def, _) => {
+        ItemKind::Struct(ident, _, def) | ItemKind::Union(ident, _, def) => {
             let adt_kind = match item.kind {
                 ItemKind::Struct(..) => AdtKind::Struct,
                 _ => AdtKind::Union,
diff --git a/compiler/rustc_hir_analysis/src/collect/resolve_bound_vars.rs b/compiler/rustc_hir_analysis/src/collect/resolve_bound_vars.rs
index 709446d09cd2..d45f0475e991 100644
--- a/compiler/rustc_hir_analysis/src/collect/resolve_bound_vars.rs
+++ b/compiler/rustc_hir_analysis/src/collect/resolve_bound_vars.rs
@@ -634,11 +634,11 @@ impl<'a, 'tcx> Visitor<'tcx> for BoundVarContext<'a, 'tcx> {
                 // These sorts of items have no lifetime parameters at all.
                 intravisit::walk_item(self, item);
             }
-            hir::ItemKind::TyAlias(_, _, generics)
-            | hir::ItemKind::Const(_, _, generics, _)
-            | hir::ItemKind::Enum(_, _, generics)
-            | hir::ItemKind::Struct(_, _, generics)
-            | hir::ItemKind::Union(_, _, generics)
+            hir::ItemKind::TyAlias(_, generics, _)
+            | hir::ItemKind::Const(_, generics, _, _)
+            | hir::ItemKind::Enum(_, generics, _)
+            | hir::ItemKind::Struct(_, generics, _)
+            | hir::ItemKind::Union(_, generics, _)
             | hir::ItemKind::Trait(_, _, _, generics, ..)
             | hir::ItemKind::TraitAlias(_, generics, ..)
             | hir::ItemKind::Impl(&hir::Impl { generics, .. }) => {
diff --git a/compiler/rustc_hir_analysis/src/collect/type_of.rs b/compiler/rustc_hir_analysis/src/collect/type_of.rs
index c20b14df7704..141d96b57e57 100644
--- a/compiler/rustc_hir_analysis/src/collect/type_of.rs
+++ b/compiler/rustc_hir_analysis/src/collect/type_of.rs
@@ -206,7 +206,7 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::EarlyBinder<'_
         },
 
         Node::Item(item) => match item.kind {
-            ItemKind::Static(ident, ty, .., body_id) => {
+            ItemKind::Static(_, ident, ty, body_id) => {
                 if ty.is_suggestable_infer_ty() {
                     infer_placeholder_type(
                         icx.lowerer(),
@@ -220,7 +220,7 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::EarlyBinder<'_
                     icx.lower_ty(ty)
                 }
             }
-            ItemKind::Const(ident, ty, _, body_id) => {
+            ItemKind::Const(ident, _, ty, body_id) => {
                 if ty.is_suggestable_infer_ty() {
                     infer_placeholder_type(
                         icx.lowerer(),
@@ -234,7 +234,7 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::EarlyBinder<'_
                     icx.lower_ty(ty)
                 }
             }
-            ItemKind::TyAlias(_, self_ty, _) => icx.lower_ty(self_ty),
+            ItemKind::TyAlias(_, _, self_ty) => icx.lower_ty(self_ty),
             ItemKind::Impl(hir::Impl { self_ty, .. }) => match self_ty.find_self_aliases() {
                 spans if spans.len() > 0 => {
                     let guar = tcx
@@ -532,5 +532,5 @@ pub(crate) fn type_alias_is_lazy<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) ->
             }
         }
     }
-    HasTait.visit_ty_unambig(tcx.hir_expect_item(def_id).expect_ty_alias().1).is_break()
+    HasTait.visit_ty_unambig(tcx.hir_expect_item(def_id).expect_ty_alias().2).is_break()
 }
diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/lint.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/lint.rs
index 1f4692b19f1a..9abae33ffdbb 100644
--- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/lint.rs
+++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/lint.rs
@@ -141,7 +141,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
 
         let generics = match tcx.hir_node_by_def_id(parent_item) {
             hir::Node::Item(hir::Item {
-                kind: hir::ItemKind::Struct(_, variant, generics),
+                kind: hir::ItemKind::Struct(_, generics, variant),
                 ..
             }) => {
                 if !variant.fields().iter().any(|field| field.hir_id == parent_hir_id) {
@@ -149,7 +149,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
                 }
                 generics
             }
-            hir::Node::Item(hir::Item { kind: hir::ItemKind::Enum(_, def, generics), .. }) => {
+            hir::Node::Item(hir::Item { kind: hir::ItemKind::Enum(_, generics, def), .. }) => {
                 if !def
                     .variants
                     .iter()
@@ -269,7 +269,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
             hir::Node::Field(field) => {
                 // Enums can't have unsized fields, fields can only have an unsized tail field.
                 if let hir::Node::Item(hir::Item {
-                    kind: hir::ItemKind::Struct(_, variant, _), ..
+                    kind: hir::ItemKind::Struct(_, _, variant), ..
                 }) = tcx.parent_hir_node(field.hir_id)
                     && variant
                         .fields()
diff --git a/compiler/rustc_hir_analysis/src/hir_wf_check.rs b/compiler/rustc_hir_analysis/src/hir_wf_check.rs
index 64c1a78bd1c8..4633f3951a78 100644
--- a/compiler/rustc_hir_analysis/src/hir_wf_check.rs
+++ b/compiler/rustc_hir_analysis/src/hir_wf_check.rs
@@ -145,9 +145,9 @@ fn diagnostic_hir_wf_check<'tcx>(
                 ref item => bug!("Unexpected TraitItem {:?}", item),
             },
             hir::Node::Item(item) => match item.kind {
-                hir::ItemKind::TyAlias(_, ty, _)
-                | hir::ItemKind::Static(_, ty, _, _)
-                | hir::ItemKind::Const(_, ty, _, _) => vec![ty],
+                hir::ItemKind::TyAlias(_, _, ty)
+                | hir::ItemKind::Static(_, _, ty, _)
+                | hir::ItemKind::Const(_, _, ty, _) => vec![ty],
                 hir::ItemKind::Impl(impl_) => match &impl_.of_trait {
                     Some(t) => t
                         .path
diff --git a/compiler/rustc_hir_pretty/src/lib.rs b/compiler/rustc_hir_pretty/src/lib.rs
index 04f9c831b0ac..b23b3125c59a 100644
--- a/compiler/rustc_hir_pretty/src/lib.rs
+++ b/compiler/rustc_hir_pretty/src/lib.rs
@@ -477,10 +477,10 @@ impl<'a> State<'a> {
             hir::ForeignItemKind::Fn(sig, arg_idents, generics) => {
                 let (cb, ib) = self.head("");
                 self.print_fn(
-                    sig.decl,
                     sig.header,
                     Some(item.ident.name),
                     generics,
+                    sig.decl,
                     arg_idents,
                     None,
                 );
@@ -593,7 +593,7 @@ impl<'a> State<'a> {
                 self.end(ib);
                 self.end(cb);
             }
-            hir::ItemKind::Static(ident, ty, m, expr) => {
+            hir::ItemKind::Static(m, ident, ty, expr) => {
                 let (cb, ib) = self.head("static");
                 if m.is_mut() {
                     self.word_space("mut");
@@ -609,7 +609,7 @@ impl<'a> State<'a> {
                 self.word(";");
                 self.end(cb);
             }
-            hir::ItemKind::Const(ident, ty, generics, expr) => {
+            hir::ItemKind::Const(ident, generics, ty, expr) => {
                 let (cb, ib) = self.head("const");
                 self.print_ident(ident);
                 self.print_generic_params(generics.params);
@@ -626,7 +626,7 @@ impl<'a> State<'a> {
             }
             hir::ItemKind::Fn { ident, sig, generics, body, .. } => {
                 let (cb, ib) = self.head("");
-                self.print_fn(sig.decl, sig.header, Some(ident.name), generics, &[], Some(body));
+                self.print_fn(sig.header, Some(ident.name), generics, sig.decl, &[], Some(body));
                 self.word(" ");
                 self.end(ib);
                 self.end(cb);
@@ -660,7 +660,7 @@ impl<'a> State<'a> {
                 self.end(cb);
                 self.end(ib);
             }
-            hir::ItemKind::TyAlias(ident, ty, generics) => {
+            hir::ItemKind::TyAlias(ident, generics, ty) => {
                 let (cb, ib) = self.head("type");
                 self.print_ident(ident);
                 self.print_generic_params(generics.params);
@@ -673,16 +673,16 @@ impl<'a> State<'a> {
                 self.word(";");
                 self.end(cb);
             }
-            hir::ItemKind::Enum(ident, ref enum_definition, params) => {
-                self.print_enum_def(enum_definition, params, ident.name, item.span);
+            hir::ItemKind::Enum(ident, generics, ref enum_def) => {
+                self.print_enum_def(ident.name, generics, enum_def, item.span);
             }
-            hir::ItemKind::Struct(ident, ref struct_def, generics) => {
+            hir::ItemKind::Struct(ident, generics, ref struct_def) => {
                 let (cb, ib) = self.head("struct");
-                self.print_struct(struct_def, generics, ident.name, item.span, true, cb, ib);
+                self.print_struct(ident.name, generics, struct_def, item.span, true, cb, ib);
             }
-            hir::ItemKind::Union(ident, ref struct_def, generics) => {
+            hir::ItemKind::Union(ident, generics, ref struct_def) => {
                 let (cb, ib) = self.head("union");
-                self.print_struct(struct_def, generics, ident.name, item.span, true, cb, ib);
+                self.print_struct(ident.name, generics, struct_def, item.span, true, cb, ib);
             }
             hir::ItemKind::Impl(&hir::Impl {
                 constness,
@@ -791,9 +791,9 @@ impl<'a> State<'a> {
 
     fn print_enum_def(
         &mut self,
-        enum_definition: &hir::EnumDef<'_>,
-        generics: &hir::Generics<'_>,
         name: Symbol,
+        generics: &hir::Generics<'_>,
+        enum_def: &hir::EnumDef<'_>,
         span: rustc_span::Span,
     ) {
         let (cb, ib) = self.head("enum");
@@ -801,7 +801,7 @@ impl<'a> State<'a> {
         self.print_generic_params(generics.params);
         self.print_where_clause(generics);
         self.space();
-        self.print_variants(enum_definition.variants, span, cb, ib);
+        self.print_variants(enum_def.variants, span, cb, ib);
     }
 
     fn print_variants(
@@ -834,9 +834,9 @@ impl<'a> State<'a> {
 
     fn print_struct(
         &mut self,
-        struct_def: &hir::VariantData<'_>,
-        generics: &hir::Generics<'_>,
         name: Symbol,
+        generics: &hir::Generics<'_>,
+        struct_def: &hir::VariantData<'_>,
         span: rustc_span::Span,
         print_finalizer: bool,
         cb: BoxMarker,
@@ -886,7 +886,7 @@ impl<'a> State<'a> {
     pub fn print_variant(&mut self, v: &hir::Variant<'_>) {
         let (cb, ib) = self.head("");
         let generics = hir::Generics::empty();
-        self.print_struct(&v.data, generics, v.ident.name, v.span, false, cb, ib);
+        self.print_struct(v.ident.name, generics, &v.data, v.span, false, cb, ib);
         if let Some(ref d) = v.disr_expr {
             self.space();
             self.word_space("=");
@@ -902,7 +902,7 @@ impl<'a> State<'a> {
         arg_idents: &[Option<Ident>],
         body_id: Option<hir::BodyId>,
     ) {
-        self.print_fn(m.decl, m.header, Some(ident.name), generics, arg_idents, body_id);
+        self.print_fn(m.header, Some(ident.name), generics, m.decl, arg_idents, body_id);
     }
 
     fn print_trait_item(&mut self, ti: &hir::TraitItem<'_>) {
@@ -2141,10 +2141,10 @@ impl<'a> State<'a> {
 
     fn print_fn(
         &mut self,
-        decl: &hir::FnDecl<'_>,
         header: hir::FnHeader,
         name: Option<Symbol>,
         generics: &hir::Generics<'_>,
+        decl: &hir::FnDecl<'_>,
         arg_idents: &[Option<Ident>],
         body_id: Option<hir::BodyId>,
     ) {
@@ -2483,7 +2483,6 @@ impl<'a> State<'a> {
         self.print_formal_generic_params(generic_params);
         let generics = hir::Generics::empty();
         self.print_fn(
-            decl,
             hir::FnHeader {
                 safety: safety.into(),
                 abi,
@@ -2492,6 +2491,7 @@ impl<'a> State<'a> {
             },
             name,
             generics,
+            decl,
             arg_idents,
             None,
         );
diff --git a/compiler/rustc_hir_typeck/src/cast.rs b/compiler/rustc_hir_typeck/src/cast.rs
index c044c4f7c37d..e144a6ab5999 100644
--- a/compiler/rustc_hir_typeck/src/cast.rs
+++ b/compiler/rustc_hir_typeck/src/cast.rs
@@ -408,6 +408,16 @@ impl<'a, 'tcx> CastCheck<'tcx> {
                     self.expr_ty,
                     fcx.ty_to_string(self.cast_ty)
                 );
+
+                if let Ok(snippet) = fcx.tcx.sess.source_map().span_to_snippet(self.expr_span)
+                    && matches!(self.expr.kind, ExprKind::AddrOf(..))
+                {
+                    err.note(format!(
+                        "casting reference expression `{}` because `&` binds tighter than `as`",
+                        snippet
+                    ));
+                }
+
                 let mut sugg = None;
                 let mut sugg_mutref = false;
                 if let ty::Ref(reg, cast_ty, mutbl) = *self.cast_ty.kind() {
diff --git a/compiler/rustc_hir_typeck/src/demand.rs b/compiler/rustc_hir_typeck/src/demand.rs
index 8182851a015b..152c88ad92a5 100644
--- a/compiler/rustc_hir_typeck/src/demand.rs
+++ b/compiler/rustc_hir_typeck/src/demand.rs
@@ -722,8 +722,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     )) => {
                         if let Some(hir::Node::Item(hir::Item {
                             kind:
-                                hir::ItemKind::Static(ident, ty, ..)
-                                | hir::ItemKind::Const(ident, ty, ..),
+                                hir::ItemKind::Static(_, ident, ty, _)
+                                | hir::ItemKind::Const(ident, _, ty, _),
                             ..
                         })) = self.tcx.hir_get_if_local(*def_id)
                         {
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs
index 43b662ca453d..1c3bc338d85b 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs
@@ -2713,6 +2713,31 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         ));
                     }
 
+                    // Don't try to suggest ref/deref on an `if` expression, because:
+                    // - The `if` could be part of a desugared `if else` statement,
+                    //   which would create impossible suggestions such as `if ... { ... } else &if { ... } else { ... }`.
+                    // - In general the suggestions it creates such as `&if ... { ... } else { ... }` are not very helpful.
+                    // We try to generate a suggestion such as `if ... { &... } else { &... }` instead.
+                    if let hir::ExprKind::If(_c, then, els) = expr.kind {
+                        // The `then` of a `Expr::If` always contains a block, and that block may have a final expression that we can borrow
+                        // If the block does not have a final expression, it will return () and we do not make a suggestion to borrow that.
+                        let ExprKind::Block(then, _) = then.kind else { return None };
+                        let Some(then) = then.expr else { return None };
+                        let (mut suggs, help, app, verbose, mutref) =
+                            self.suggest_deref_or_ref(then, checked_ty, expected)?;
+
+                        // If there is no `else`, the return type of this `if` will be (), so suggesting to change the `then` block is useless
+                        let els_expr = match els?.kind {
+                            ExprKind::Block(block, _) => block.expr?,
+                            _ => els?,
+                        };
+                        let (else_suggs, ..) =
+                            self.suggest_deref_or_ref(els_expr, checked_ty, expected)?;
+                        suggs.extend(else_suggs);
+
+                        return Some((suggs, help, app, verbose, mutref));
+                    }
+
                     if let Some((sugg, msg)) = self.can_use_as_ref(expr) {
                         return Some((
                             sugg,
diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs
index 95e31e4af1e3..47b80135bae9 100644
--- a/compiler/rustc_lint/src/builtin.rs
+++ b/compiler/rustc_lint/src/builtin.rs
@@ -545,22 +545,22 @@ impl<'tcx> LateLintPass<'tcx> for MissingCopyImplementations {
             return;
         }
         let (def, ty) = match item.kind {
-            hir::ItemKind::Struct(_, _, ast_generics) => {
-                if !ast_generics.params.is_empty() {
+            hir::ItemKind::Struct(_, generics, _) => {
+                if !generics.params.is_empty() {
                     return;
                 }
                 let def = cx.tcx.adt_def(item.owner_id);
                 (def, Ty::new_adt(cx.tcx, def, ty::List::empty()))
             }
-            hir::ItemKind::Union(_, _, ast_generics) => {
-                if !ast_generics.params.is_empty() {
+            hir::ItemKind::Union(_, generics, _) => {
+                if !generics.params.is_empty() {
                     return;
                 }
                 let def = cx.tcx.adt_def(item.owner_id);
                 (def, Ty::new_adt(cx.tcx, def, ty::List::empty()))
             }
-            hir::ItemKind::Enum(_, _, ast_generics) => {
-                if !ast_generics.params.is_empty() {
+            hir::ItemKind::Enum(_, generics, _) => {
+                if !generics.params.is_empty() {
                     return;
                 }
                 let def = cx.tcx.adt_def(item.owner_id);
@@ -1422,7 +1422,7 @@ impl TypeAliasBounds {
 
 impl<'tcx> LateLintPass<'tcx> for TypeAliasBounds {
     fn check_item(&mut self, cx: &LateContext<'_>, item: &hir::Item<'_>) {
-        let hir::ItemKind::TyAlias(_, hir_ty, generics) = item.kind else { return };
+        let hir::ItemKind::TyAlias(_, generics, hir_ty) = item.kind else { return };
 
         // There must not be a where clause.
         if generics.predicates.is_empty() {
@@ -2125,9 +2125,9 @@ impl<'tcx> LateLintPass<'tcx> for ExplicitOutlivesRequirements {
         use rustc_middle::middle::resolve_bound_vars::ResolvedArg;
 
         let def_id = item.owner_id.def_id;
-        if let hir::ItemKind::Struct(_, _, hir_generics)
-        | hir::ItemKind::Enum(_, _, hir_generics)
-        | hir::ItemKind::Union(_, _, hir_generics) = item.kind
+        if let hir::ItemKind::Struct(_, generics, _)
+        | hir::ItemKind::Enum(_, generics, _)
+        | hir::ItemKind::Union(_, generics, _) = item.kind
         {
             let inferred_outlives = cx.tcx.inferred_outlives_of(def_id);
             if inferred_outlives.is_empty() {
@@ -2135,7 +2135,7 @@ impl<'tcx> LateLintPass<'tcx> for ExplicitOutlivesRequirements {
             }
 
             let ty_generics = cx.tcx.generics_of(def_id);
-            let num_where_predicates = hir_generics
+            let num_where_predicates = generics
                 .predicates
                 .iter()
                 .filter(|predicate| predicate.kind.in_where_clause())
@@ -2145,7 +2145,7 @@ impl<'tcx> LateLintPass<'tcx> for ExplicitOutlivesRequirements {
             let mut lint_spans = Vec::new();
             let mut where_lint_spans = Vec::new();
             let mut dropped_where_predicate_count = 0;
-            for (i, where_predicate) in hir_generics.predicates.iter().enumerate() {
+            for (i, where_predicate) in generics.predicates.iter().enumerate() {
                 let (relevant_lifetimes, bounds, predicate_span, in_where_clause) =
                     match where_predicate.kind {
                         hir::WherePredicateKind::RegionPredicate(predicate) => {
@@ -2228,7 +2228,7 @@ impl<'tcx> LateLintPass<'tcx> for ExplicitOutlivesRequirements {
                     } else if i + 1 < num_where_predicates {
                         // If all the bounds on a predicate were inferable and there are
                         // further predicates, we want to eat the trailing comma.
-                        let next_predicate_span = hir_generics.predicates[i + 1].span;
+                        let next_predicate_span = generics.predicates[i + 1].span;
                         if next_predicate_span.from_expansion() {
                             where_lint_spans.push(predicate_span);
                         } else {
@@ -2237,7 +2237,7 @@ impl<'tcx> LateLintPass<'tcx> for ExplicitOutlivesRequirements {
                         }
                     } else {
                         // Eat the optional trailing comma after the last predicate.
-                        let where_span = hir_generics.where_clause_span;
+                        let where_span = generics.where_clause_span;
                         if where_span.from_expansion() {
                             where_lint_spans.push(predicate_span);
                         } else {
@@ -2255,18 +2255,18 @@ impl<'tcx> LateLintPass<'tcx> for ExplicitOutlivesRequirements {
 
             // If all predicates in where clause are inferable, drop the entire clause
             // (including the `where`)
-            if hir_generics.has_where_clause_predicates
+            if generics.has_where_clause_predicates
                 && dropped_where_predicate_count == num_where_predicates
             {
-                let where_span = hir_generics.where_clause_span;
+                let where_span = generics.where_clause_span;
                 // Extend the where clause back to the closing `>` of the
                 // generics, except for tuple struct, which have the `where`
                 // after the fields of the struct.
                 let full_where_span =
-                    if let hir::ItemKind::Struct(_, hir::VariantData::Tuple(..), _) = item.kind {
+                    if let hir::ItemKind::Struct(_, _, hir::VariantData::Tuple(..)) = item.kind {
                         where_span
                     } else {
-                        hir_generics.span.shrink_to_hi().to(where_span)
+                        generics.span.shrink_to_hi().to(where_span)
                     };
 
                 // Due to macro expansions, the `full_where_span` might not actually contain all
diff --git a/compiler/rustc_lint/src/default_could_be_derived.rs b/compiler/rustc_lint/src/default_could_be_derived.rs
index 78d129642dc7..7734f441df2e 100644
--- a/compiler/rustc_lint/src/default_could_be_derived.rs
+++ b/compiler/rustc_lint/src/default_could_be_derived.rs
@@ -95,8 +95,8 @@ impl<'tcx> LateLintPass<'tcx> for DefaultCouldBeDerived {
                 kind:
                     hir::ItemKind::Struct(
                         _,
-                        hir::VariantData::Struct { fields, recovered: _ },
                         _generics,
+                        hir::VariantData::Struct { fields, recovered: _ },
                     ),
                 ..
             })) => fields.iter().map(|f| (f.ident.name, f)).collect::<FxHashMap<_, _>>(),
diff --git a/compiler/rustc_lint/src/non_local_def.rs b/compiler/rustc_lint/src/non_local_def.rs
index 9ed11d9cc82f..b877f909fc02 100644
--- a/compiler/rustc_lint/src/non_local_def.rs
+++ b/compiler/rustc_lint/src/non_local_def.rs
@@ -183,7 +183,7 @@ impl<'tcx> LateLintPass<'tcx> for NonLocalDefinitions {
                     && parent_opt_item_name != Some(kw::Underscore)
                     && let Some(parent) = parent.as_local()
                     && let Node::Item(item) = cx.tcx.hir_node_by_def_id(parent)
-                    && let ItemKind::Const(ident, ty, _, _) = item.kind
+                    && let ItemKind::Const(ident, _, ty, _) = item.kind
                     && let TyKind::Tup(&[]) = ty.kind
                 {
                     Some(ident.span)
diff --git a/compiler/rustc_lint/src/nonstandard_style.rs b/compiler/rustc_lint/src/nonstandard_style.rs
index 048d377b78fb..31c180744668 100644
--- a/compiler/rustc_lint/src/nonstandard_style.rs
+++ b/compiler/rustc_lint/src/nonstandard_style.rs
@@ -513,7 +513,7 @@ impl<'tcx> LateLintPass<'tcx> for NonUpperCaseGlobals {
     fn check_item(&mut self, cx: &LateContext<'_>, it: &hir::Item<'_>) {
         let attrs = cx.tcx.hir_attrs(it.hir_id());
         match it.kind {
-            hir::ItemKind::Static(ident, ..)
+            hir::ItemKind::Static(_, ident, ..)
                 if !ast::attr::contains_name(attrs, sym::no_mangle) =>
             {
                 NonUpperCaseGlobals::check_upper_case(cx, "static variable", &ident);
diff --git a/compiler/rustc_lint/src/types.rs b/compiler/rustc_lint/src/types.rs
index af134622d38c..77dc63351136 100644
--- a/compiler/rustc_lint/src/types.rs
+++ b/compiler/rustc_lint/src/types.rs
@@ -1710,7 +1710,7 @@ impl ImproperCTypesDefinitions {
             && cx.tcx.sess.target.os == "aix"
             && !adt_def.all_fields().next().is_none()
         {
-            let struct_variant_data = item.expect_struct().1;
+            let struct_variant_data = item.expect_struct().2;
             for field_def in struct_variant_data.fields().iter().skip(1) {
                 // Struct fields (after the first field) are checked for the
                 // power alignment rule, as fields after the first are likely
@@ -1735,9 +1735,9 @@ impl ImproperCTypesDefinitions {
 impl<'tcx> LateLintPass<'tcx> for ImproperCTypesDefinitions {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::Item<'tcx>) {
         match item.kind {
-            hir::ItemKind::Static(_, ty, ..)
-            | hir::ItemKind::Const(_, ty, ..)
-            | hir::ItemKind::TyAlias(_, ty, ..) => {
+            hir::ItemKind::Static(_, _, ty, _)
+            | hir::ItemKind::Const(_, _, ty, _)
+            | hir::ItemKind::TyAlias(_, _, ty) => {
                 self.check_ty_maybe_containing_foreign_fnptr(
                     cx,
                     ty,
@@ -1804,7 +1804,7 @@ declare_lint_pass!(VariantSizeDifferences => [VARIANT_SIZE_DIFFERENCES]);
 
 impl<'tcx> LateLintPass<'tcx> for VariantSizeDifferences {
     fn check_item(&mut self, cx: &LateContext<'_>, it: &hir::Item<'_>) {
-        if let hir::ItemKind::Enum(_, ref enum_definition, _) = it.kind {
+        if let hir::ItemKind::Enum(_, _, ref enum_definition) = it.kind {
             let t = cx.tcx.type_of(it.owner_id).instantiate_identity();
             let ty = cx.tcx.erase_regions(t);
             let Ok(layout) = cx.layout_of(ty) else { return };
diff --git a/compiler/rustc_middle/src/hir/map.rs b/compiler/rustc_middle/src/hir/map.rs
index 9c8f1c9eccf3..3de97c8c0d99 100644
--- a/compiler/rustc_middle/src/hir/map.rs
+++ b/compiler/rustc_middle/src/hir/map.rs
@@ -920,7 +920,7 @@ impl<'tcx> TyCtxt<'tcx> {
             }) => until_within(*outer_span, generics.where_clause_span),
             // Constants and Statics.
             Node::Item(Item {
-                kind: ItemKind::Const(_, ty, ..) | ItemKind::Static(_, ty, ..),
+                kind: ItemKind::Const(_, _, ty, _) | ItemKind::Static(_, _, ty, _),
                 span: outer_span,
                 ..
             })
diff --git a/compiler/rustc_mir_build/src/builder/mod.rs b/compiler/rustc_mir_build/src/builder/mod.rs
index 127b191e3353..3d5f6f4cf451 100644
--- a/compiler/rustc_mir_build/src/builder/mod.rs
+++ b/compiler/rustc_mir_build/src/builder/mod.rs
@@ -558,7 +558,7 @@ fn construct_const<'a, 'tcx>(
     // Figure out what primary body this item has.
     let (span, const_ty_span) = match tcx.hir_node(hir_id) {
         Node::Item(hir::Item {
-            kind: hir::ItemKind::Static(_, ty, _, _) | hir::ItemKind::Const(_, ty, _, _),
+            kind: hir::ItemKind::Static(_, _, ty, _) | hir::ItemKind::Const(_, _, ty, _),
             span,
             ..
         })
diff --git a/compiler/rustc_mir_transform/src/lower_intrinsics.rs b/compiler/rustc_mir_transform/src/lower_intrinsics.rs
index 9c21bcfc0d26..52f4c39c09bb 100644
--- a/compiler/rustc_mir_transform/src/lower_intrinsics.rs
+++ b/compiler/rustc_mir_transform/src/lower_intrinsics.rs
@@ -262,6 +262,52 @@ impl<'tcx> crate::MirPass<'tcx> for LowerIntrinsics {
                         });
                         terminator.kind = TerminatorKind::Goto { target };
                     }
+                    sym::slice_get_unchecked => {
+                        let target = target.unwrap();
+                        let Ok([ptrish, index]) = take_array(args) else {
+                            span_bug!(
+                                terminator.source_info.span,
+                                "Wrong number of arguments for {intrinsic:?}",
+                            );
+                        };
+
+                        let place = ptrish.node.place().unwrap();
+                        assert!(!place.is_indirect());
+                        let updated_place = place.project_deeper(
+                            &[
+                                ProjectionElem::Deref,
+                                ProjectionElem::Index(
+                                    index.node.place().unwrap().as_local().unwrap(),
+                                ),
+                            ],
+                            tcx,
+                        );
+
+                        let ret_ty = generic_args.type_at(0);
+                        let rvalue = match *ret_ty.kind() {
+                            ty::RawPtr(_, Mutability::Not) => {
+                                Rvalue::RawPtr(RawPtrKind::Const, updated_place)
+                            }
+                            ty::RawPtr(_, Mutability::Mut) => {
+                                Rvalue::RawPtr(RawPtrKind::Mut, updated_place)
+                            }
+                            ty::Ref(region, _, Mutability::Not) => {
+                                Rvalue::Ref(region, BorrowKind::Shared, updated_place)
+                            }
+                            ty::Ref(region, _, Mutability::Mut) => Rvalue::Ref(
+                                region,
+                                BorrowKind::Mut { kind: MutBorrowKind::Default },
+                                updated_place,
+                            ),
+                            _ => bug!("Unknown return type {ret_ty:?}"),
+                        };
+
+                        block.statements.push(Statement {
+                            source_info: terminator.source_info,
+                            kind: StatementKind::Assign(Box::new((*destination, rvalue))),
+                        });
+                        terminator.kind = TerminatorKind::Goto { target };
+                    }
                     sym::transmute | sym::transmute_unchecked => {
                         let dst_ty = destination.ty(local_decls, tcx).ty;
                         let Ok([arg]) = take_array(args) else {
diff --git a/compiler/rustc_passes/src/check_attr.rs b/compiler/rustc_passes/src/check_attr.rs
index df8b5a6b1818..0777d442b594 100644
--- a/compiler/rustc_passes/src/check_attr.rs
+++ b/compiler/rustc_passes/src/check_attr.rs
@@ -802,7 +802,7 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
         match target {
             Target::Struct => {
                 if let Some(ItemLike::Item(hir::Item {
-                    kind: hir::ItemKind::Struct(_, hir::VariantData::Struct { fields, .. }, _),
+                    kind: hir::ItemKind::Struct(_, _, hir::VariantData::Struct { fields, .. }),
                     ..
                 })) = item
                     && !fields.is_empty()
@@ -1130,12 +1130,12 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
             return;
         };
         match item.kind {
-            ItemKind::Enum(_, _, generics) | ItemKind::Struct(_, _, generics)
+            ItemKind::Enum(_, generics, _) | ItemKind::Struct(_, generics, _)
                 if generics.params.len() != 0 => {}
             ItemKind::Trait(_, _, _, generics, _, items)
                 if generics.params.len() != 0
                     || items.iter().any(|item| matches!(item.kind, AssocItemKind::Type)) => {}
-            ItemKind::TyAlias(_, _, generics) if generics.params.len() != 0 => {}
+            ItemKind::TyAlias(_, generics, _) if generics.params.len() != 0 => {}
             _ => {
                 self.dcx().emit_err(errors::DocSearchUnboxInvalid { span: meta.span() });
             }
@@ -2792,7 +2792,7 @@ impl<'tcx> Visitor<'tcx> for CheckAttrVisitor<'tcx> {
 }
 
 fn is_c_like_enum(item: &Item<'_>) -> bool {
-    if let ItemKind::Enum(_, ref def, _) = item.kind {
+    if let ItemKind::Enum(_, _, ref def) = item.kind {
         for variant in def.variants {
             match variant.data {
                 hir::VariantData::Unit(..) => { /* continue */ }
diff --git a/compiler/rustc_passes/src/dead.rs b/compiler/rustc_passes/src/dead.rs
index f83c7471770a..6b82252f32c2 100644
--- a/compiler/rustc_passes/src/dead.rs
+++ b/compiler/rustc_passes/src/dead.rs
@@ -736,7 +736,7 @@ fn check_item<'tcx>(
     match tcx.def_kind(id.owner_id) {
         DefKind::Enum => {
             let item = tcx.hir_item(id);
-            if let hir::ItemKind::Enum(_, ref enum_def, _) = item.kind {
+            if let hir::ItemKind::Enum(_, _, ref enum_def) = item.kind {
                 if let Some(comes_from_allow) = allow_dead_code {
                     worklist.extend(
                         enum_def.variants.iter().map(|variant| (variant.def_id, comes_from_allow)),
@@ -783,7 +783,7 @@ fn check_item<'tcx>(
         }
         DefKind::Struct => {
             let item = tcx.hir_item(id);
-            if let hir::ItemKind::Struct(_, ref variant_data, _) = item.kind
+            if let hir::ItemKind::Struct(_, _, ref variant_data) = item.kind
                 && let Some(ctor_def_id) = variant_data.ctor_def_id()
             {
                 struct_constructors.insert(ctor_def_id, item.owner_id.def_id);
@@ -1055,7 +1055,7 @@ impl<'tcx> DeadVisitor<'tcx> {
                 let tuple_fields = if let Some(parent_id) = parent_item
                     && let node = tcx.hir_node_by_def_id(parent_id)
                     && let hir::Node::Item(hir::Item {
-                        kind: hir::ItemKind::Struct(_, hir::VariantData::Tuple(fields, _, _), _),
+                        kind: hir::ItemKind::Struct(_, _, hir::VariantData::Tuple(fields, _, _)),
                         ..
                     }) = node
                 {
diff --git a/compiler/rustc_passes/src/stability.rs b/compiler/rustc_passes/src/stability.rs
index 9884386d68f8..45e26c8999a9 100644
--- a/compiler/rustc_passes/src/stability.rs
+++ b/compiler/rustc_passes/src/stability.rs
@@ -430,7 +430,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> {
                 kind = AnnotationKind::DeprecationProhibited;
                 const_stab_inherit = InheritConstStability::Yes;
             }
-            hir::ItemKind::Struct(_, ref sd, _) => {
+            hir::ItemKind::Struct(_, _, ref sd) => {
                 if let Some(ctor_def_id) = sd.ctor_def_id() {
                     self.annotate(
                         ctor_def_id,
diff --git a/compiler/rustc_privacy/src/lib.rs b/compiler/rustc_privacy/src/lib.rs
index e2dfaec61b3c..963f4c77d809 100644
--- a/compiler/rustc_privacy/src/lib.rs
+++ b/compiler/rustc_privacy/src/lib.rs
@@ -599,8 +599,8 @@ impl<'tcx> EmbargoVisitor<'tcx> {
             DefKind::Struct | DefKind::Union => {
                 // While structs and unions have type privacy, their fields do not.
                 let item = self.tcx.hir_expect_item(def_id);
-                if let hir::ItemKind::Struct(_, ref struct_def, _)
-                | hir::ItemKind::Union(_, ref struct_def, _) = item.kind
+                if let hir::ItemKind::Struct(_, _, ref struct_def)
+                | hir::ItemKind::Union(_, _, ref struct_def) = item.kind
                 {
                     for field in struct_def.fields() {
                         let field_vis = self.tcx.local_visibility(field.def_id);
@@ -725,7 +725,7 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
                     }
                 }
             }
-            hir::ItemKind::Enum(_, ref def, _) => {
+            hir::ItemKind::Enum(_, _, ref def) => {
                 if let Some(item_ev) = item_ev {
                     self.reach(item.owner_id.def_id, item_ev).generics().predicates();
                 }
@@ -763,8 +763,8 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
                     }
                 }
             }
-            hir::ItemKind::Struct(_, ref struct_def, _)
-            | hir::ItemKind::Union(_, ref struct_def, _) => {
+            hir::ItemKind::Struct(_, _, ref struct_def)
+            | hir::ItemKind::Union(_, _, ref struct_def) => {
                 if let Some(item_ev) = item_ev {
                     self.reach(item.owner_id.def_id, item_ev).generics().predicates();
                     for field in struct_def.fields() {
@@ -868,7 +868,7 @@ impl<'a, 'tcx> Visitor<'tcx> for TestReachabilityVisitor<'a, 'tcx> {
         self.effective_visibility_diagnostic(item.owner_id.def_id);
 
         match item.kind {
-            hir::ItemKind::Enum(_, ref def, _) => {
+            hir::ItemKind::Enum(_, _, ref def) => {
                 for variant in def.variants.iter() {
                     self.effective_visibility_diagnostic(variant.def_id);
                     if let Some(ctor_def_id) = variant.data.ctor_def_id() {
@@ -879,7 +879,7 @@ impl<'a, 'tcx> Visitor<'tcx> for TestReachabilityVisitor<'a, 'tcx> {
                     }
                 }
             }
-            hir::ItemKind::Struct(_, ref def, _) | hir::ItemKind::Union(_, ref def, _) => {
+            hir::ItemKind::Struct(_, _, ref def) | hir::ItemKind::Union(_, _, ref def) => {
                 if let Some(ctor_def_id) = def.ctor_def_id() {
                     self.effective_visibility_diagnostic(ctor_def_id);
                 }
@@ -1651,7 +1651,7 @@ impl<'tcx> PrivateItemsInPublicInterfacesChecker<'_, 'tcx> {
             }
             DefKind::Enum => {
                 let item = tcx.hir_item(id);
-                if let hir::ItemKind::Enum(_, ref def, _) = item.kind {
+                if let hir::ItemKind::Enum(_, _, ref def) = item.kind {
                     self.check_unnameable(item.owner_id.def_id, effective_vis);
 
                     self.check(item.owner_id.def_id, item_visibility, effective_vis)
@@ -1689,8 +1689,8 @@ impl<'tcx> PrivateItemsInPublicInterfacesChecker<'_, 'tcx> {
             // Subitems of structs and unions have their own publicity.
             DefKind::Struct | DefKind::Union => {
                 let item = tcx.hir_item(id);
-                if let hir::ItemKind::Struct(_, ref struct_def, _)
-                | hir::ItemKind::Union(_, ref struct_def, _) = item.kind
+                if let hir::ItemKind::Struct(_, _, ref struct_def)
+                | hir::ItemKind::Union(_, _, ref struct_def) = item.kind
                 {
                     self.check_unnameable(item.owner_id.def_id, effective_vis);
                     self.check(item.owner_id.def_id, item_visibility, effective_vis)
diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
index ae94169b01dc..970faf2997c5 100644
--- a/compiler/rustc_span/src/symbol.rs
+++ b/compiler/rustc_span/src/symbol.rs
@@ -2000,6 +2000,7 @@ symbols! {
         slice,
         slice_from_raw_parts,
         slice_from_raw_parts_mut,
+        slice_get_unchecked,
         slice_into_vec,
         slice_iter,
         slice_len_fn,
diff --git a/compiler/rustc_target/src/spec/targets/aarch64_pc_windows_gnullvm.rs b/compiler/rustc_target/src/spec/targets/aarch64_pc_windows_gnullvm.rs
index a8b133d19bb0..eee668cc67ed 100644
--- a/compiler/rustc_target/src/spec/targets/aarch64_pc_windows_gnullvm.rs
+++ b/compiler/rustc_target/src/spec/targets/aarch64_pc_windows_gnullvm.rs
@@ -1,4 +1,4 @@
-use crate::spec::{Target, TargetMetadata, base};
+use crate::spec::{FramePointer, Target, TargetMetadata, base};
 
 pub(crate) fn target() -> Target {
     let mut base = base::windows_gnullvm::opts();
@@ -6,6 +6,12 @@ pub(crate) fn target() -> Target {
     base.features = "+v8a,+neon,+fp-armv8".into();
     base.linker = Some("aarch64-w64-mingw32-clang".into());
 
+    // Microsoft recommends enabling frame pointers on Arm64 Windows.
+    // From https://learn.microsoft.com/en-us/cpp/build/arm64-windows-abi-conventions?view=msvc-170#integer-registers
+    // "The frame pointer (x29) is required for compatibility with fast stack walking used by ETW
+    // and other services. It must point to the previous {x29, x30} pair on the stack."
+    base.frame_pointer = FramePointer::NonLeaf;
+
     Target {
         llvm_target: "aarch64-pc-windows-gnu".into(),
         metadata: TargetMetadata {
diff --git a/compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs b/compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs
index aeadb32ac2b4..8e2137da6552 100644
--- a/compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs
+++ b/compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs
@@ -2026,7 +2026,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
                 }
                 LetVisitor { span }.visit_body(body).break_value()
             }
-            hir::Node::Item(hir::Item { kind: hir::ItemKind::Const(_, ty, _, _), .. }) => {
+            hir::Node::Item(hir::Item { kind: hir::ItemKind::Const(_, _, ty, _), .. }) => {
                 Some(&ty.peel_refs().kind)
             }
             _ => None,
diff --git a/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs b/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs
index 6863857f9ecb..c4f1f7d712a7 100644
--- a/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs
+++ b/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs
@@ -351,14 +351,14 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
 
                 hir::Node::Item(hir::Item {
                     kind:
-                        hir::ItemKind::Struct(_, _, generics)
-                        | hir::ItemKind::Enum(_, _, generics)
-                        | hir::ItemKind::Union(_, _, generics)
+                        hir::ItemKind::Struct(_, generics, _)
+                        | hir::ItemKind::Enum(_, generics, _)
+                        | hir::ItemKind::Union(_, generics, _)
                         | hir::ItemKind::Trait(_, _, _, generics, ..)
                         | hir::ItemKind::Impl(hir::Impl { generics, .. })
                         | hir::ItemKind::Fn { generics, .. }
-                        | hir::ItemKind::TyAlias(_, _, generics)
-                        | hir::ItemKind::Const(_, _, generics, _)
+                        | hir::ItemKind::TyAlias(_, generics, _)
+                        | hir::ItemKind::Const(_, generics, _, _)
                         | hir::ItemKind::TraitAlias(_, generics, _),
                     ..
                 })
@@ -411,14 +411,14 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
 
                 hir::Node::Item(hir::Item {
                     kind:
-                        hir::ItemKind::Struct(_, _, generics)
-                        | hir::ItemKind::Enum(_, _, generics)
-                        | hir::ItemKind::Union(_, _, generics)
+                        hir::ItemKind::Struct(_, generics, _)
+                        | hir::ItemKind::Enum(_, generics, _)
+                        | hir::ItemKind::Union(_, generics, _)
                         | hir::ItemKind::Trait(_, _, _, generics, ..)
                         | hir::ItemKind::Impl(hir::Impl { generics, .. })
                         | hir::ItemKind::Fn { generics, .. }
-                        | hir::ItemKind::TyAlias(_, _, generics)
-                        | hir::ItemKind::Const(_, _, generics, _)
+                        | hir::ItemKind::TyAlias(_, generics, _)
+                        | hir::ItemKind::Const(_, generics, _, _)
                         | hir::ItemKind::TraitAlias(_, generics, _),
                     ..
                 }) if !param_ty => {
diff --git a/library/Cargo.lock b/library/Cargo.lock
index 02018057ed53..0c75977ee798 100644
--- a/library/Cargo.lock
+++ b/library/Cargo.lock
@@ -61,9 +61,9 @@ dependencies = [
 
 [[package]]
 name = "compiler_builtins"
-version = "0.1.159"
+version = "0.1.160"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "448068da8f2326b2a0472353cb401dd8795a89c007ef30fff90f50706e862e72"
+checksum = "6376049cfa92c0aa8b9ac95fae22184b981c658208d4ed8a1dc553cd83612895"
 dependencies = [
  "cc",
  "rustc-std-workspace-core",
diff --git a/library/alloc/Cargo.toml b/library/alloc/Cargo.toml
index 9d0d957226d2..365c9dc00dfc 100644
--- a/library/alloc/Cargo.toml
+++ b/library/alloc/Cargo.toml
@@ -16,7 +16,7 @@ bench = false
 
 [dependencies]
 core = { path = "../core", public = true }
-compiler_builtins = { version = "=0.1.159", features = ['rustc-dep-of-std'] }
+compiler_builtins = { version = "=0.1.160", features = ['rustc-dep-of-std'] }
 
 [features]
 compiler-builtins-mem = ['compiler_builtins/mem']
diff --git a/library/core/src/clone.rs b/library/core/src/clone.rs
index c237ac84cf40..2c0662c96290 100644
--- a/library/core/src/clone.rs
+++ b/library/core/src/clone.rs
@@ -38,7 +38,16 @@
 
 mod uninit;
 
-/// A common trait for the ability to explicitly duplicate an object.
+/// A common trait that allows explicit creation of a duplicate value.
+///
+/// Calling [`clone`] always produces a new value.
+/// However, for types that are references to other data (such as smart pointers or references),
+/// the new value may still point to the same underlying data, rather than duplicating it.
+/// See [`Clone::clone`] for more details.
+///
+/// This distinction is especially important when using `#[derive(Clone)]` on structs containing
+/// smart pointers like `Arc<Mutex<T>>` - the cloned struct will share mutable state with the
+/// original.
 ///
 /// Differs from [`Copy`] in that [`Copy`] is implicit and an inexpensive bit-wise copy, while
 /// `Clone` is always explicit and may or may not be expensive. In order to enforce
@@ -147,7 +156,16 @@ mod uninit;
 #[rustc_diagnostic_item = "Clone"]
 #[rustc_trivial_field_reads]
 pub trait Clone: Sized {
-    /// Returns a copy of the value.
+    /// Returns a duplicate of the value.
+    ///
+    /// Note that what "duplicate" means varies by type:
+    /// - For most types, this creates a deep, independent copy
+    /// - For reference types like `&T`, this creates another reference to the same value
+    /// - For smart pointers like [`Arc`] or [`Rc`], this increments the reference count
+    ///   but still points to the same underlying data
+    ///
+    /// [`Arc`]: ../../std/sync/struct.Arc.html
+    /// [`Rc`]: ../../std/rc/struct.Rc.html
     ///
     /// # Examples
     ///
@@ -157,6 +175,23 @@ pub trait Clone: Sized {
     ///
     /// assert_eq!("Hello", hello.clone());
     /// ```
+    ///
+    /// Example with a reference-counted type:
+    ///
+    /// ```
+    /// use std::sync::{Arc, Mutex};
+    ///
+    /// let data = Arc::new(Mutex::new(vec![1, 2, 3]));
+    /// let data_clone = data.clone(); // Creates another Arc pointing to the same Mutex
+    ///
+    /// {
+    ///     let mut lock = data.lock().unwrap();
+    ///     lock.push(4);
+    /// }
+    ///
+    /// // Changes are visible through the clone because they share the same underlying data
+    /// assert_eq!(*data_clone.lock().unwrap(), vec![1, 2, 3, 4]);
+    /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     #[must_use = "cloning is often expensive and is not expected to have side effects"]
     // Clone::clone is special because the compiler generates MIR to implement it for some types.
diff --git a/library/core/src/intrinsics/bounds.rs b/library/core/src/intrinsics/bounds.rs
new file mode 100644
index 000000000000..046e191212cc
--- /dev/null
+++ b/library/core/src/intrinsics/bounds.rs
@@ -0,0 +1,39 @@
+//! Various traits used to restrict intrinsics to not-completely-wrong types.
+
+/// Types with a built-in dereference operator in runtime MIR,
+/// aka references and raw pointers.
+///
+/// # Safety
+/// Must actually *be* such a type.
+pub unsafe trait BuiltinDeref: Sized {
+    type Pointee: ?Sized;
+}
+
+unsafe impl<T: ?Sized> BuiltinDeref for &mut T {
+    type Pointee = T;
+}
+unsafe impl<T: ?Sized> BuiltinDeref for &T {
+    type Pointee = T;
+}
+unsafe impl<T: ?Sized> BuiltinDeref for *mut T {
+    type Pointee = T;
+}
+unsafe impl<T: ?Sized> BuiltinDeref for *const T {
+    type Pointee = T;
+}
+
+pub trait ChangePointee<U: ?Sized>: BuiltinDeref {
+    type Output;
+}
+impl<'a, T: ?Sized + 'a, U: ?Sized + 'a> ChangePointee<U> for &'a mut T {
+    type Output = &'a mut U;
+}
+impl<'a, T: ?Sized + 'a, U: ?Sized + 'a> ChangePointee<U> for &'a T {
+    type Output = &'a U;
+}
+impl<T: ?Sized, U: ?Sized> ChangePointee<U> for *mut T {
+    type Output = *mut U;
+}
+impl<T: ?Sized, U: ?Sized> ChangePointee<U> for *const T {
+    type Output = *const U;
+}
diff --git a/library/core/src/intrinsics/mod.rs b/library/core/src/intrinsics/mod.rs
index f89baef76f09..102607a19801 100644
--- a/library/core/src/intrinsics/mod.rs
+++ b/library/core/src/intrinsics/mod.rs
@@ -53,6 +53,7 @@
 use crate::marker::{ConstParamTy, DiscriminantKind, Tuple};
 use crate::ptr;
 
+mod bounds;
 pub mod fallback;
 pub mod mir;
 pub mod simd;
@@ -1730,7 +1731,7 @@ pub const fn needs_drop<T: ?Sized>() -> bool;
 #[rustc_intrinsic_const_stable_indirect]
 #[rustc_nounwind]
 #[rustc_intrinsic]
-pub const unsafe fn offset<Ptr, Delta>(dst: Ptr, offset: Delta) -> Ptr;
+pub const unsafe fn offset<Ptr: bounds::BuiltinDeref, Delta>(dst: Ptr, offset: Delta) -> Ptr;
 
 /// Calculates the offset from a pointer, potentially wrapping.
 ///
@@ -1751,6 +1752,33 @@ pub const unsafe fn offset<Ptr, Delta>(dst: Ptr, offset: Delta) -> Ptr;
 #[rustc_intrinsic]
 pub const unsafe fn arith_offset<T>(dst: *const T, offset: isize) -> *const T;
 
+/// Projects to the `index`-th element of `slice_ptr`, as the same kind of pointer
+/// as the slice was provided -- so `&mut [T] → &mut T`, `&[T] → &T`,
+/// `*mut [T] → *mut T`, or `*const [T] → *const T` -- without a bounds check.
+///
+/// This is exposed via `<usize as SliceIndex>::get(_unchecked)(_mut)`,
+/// and isn't intended to be used elsewhere.
+///
+/// Expands in MIR to `{&, &mut, &raw const, &raw mut} (*slice_ptr)[index]`,
+/// depending on the types involved, so no backend support is needed.
+///
+/// # Safety
+///
+/// - `index < PtrMetadata(slice_ptr)`, so the indexing is in-bounds for the slice
+/// - the resulting offsetting is in-bounds of the allocated object, which is
+///   always the case for references, but needs to be upheld manually for pointers
+#[cfg(not(bootstrap))]
+#[rustc_nounwind]
+#[rustc_intrinsic]
+pub const unsafe fn slice_get_unchecked<
+    ItemPtr: bounds::ChangePointee<[T], Pointee = T, Output = SlicePtr>,
+    SlicePtr,
+    T,
+>(
+    slice_ptr: SlicePtr,
+    index: usize,
+) -> ItemPtr;
+
 /// Masks out bits of the pointer according to a mask.
 ///
 /// Note that, unlike most intrinsics, this is safe to call;
@@ -2212,28 +2240,28 @@ pub unsafe fn fmuladdf128(a: f128, b: f128, c: f128) -> f128;
 /// [`f16::floor`](../../std/primitive.f16.html#method.floor)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn floorf16(x: f16) -> f16;
+pub const unsafe fn floorf16(x: f16) -> f16;
 /// Returns the largest integer less than or equal to an `f32`.
 ///
 /// The stabilized version of this intrinsic is
 /// [`f32::floor`](../../std/primitive.f32.html#method.floor)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn floorf32(x: f32) -> f32;
+pub const unsafe fn floorf32(x: f32) -> f32;
 /// Returns the largest integer less than or equal to an `f64`.
 ///
 /// The stabilized version of this intrinsic is
 /// [`f64::floor`](../../std/primitive.f64.html#method.floor)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn floorf64(x: f64) -> f64;
+pub const unsafe fn floorf64(x: f64) -> f64;
 /// Returns the largest integer less than or equal to an `f128`.
 ///
 /// The stabilized version of this intrinsic is
 /// [`f128::floor`](../../std/primitive.f128.html#method.floor)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn floorf128(x: f128) -> f128;
+pub const unsafe fn floorf128(x: f128) -> f128;
 
 /// Returns the smallest integer greater than or equal to an `f16`.
 ///
@@ -2241,28 +2269,28 @@ pub unsafe fn floorf128(x: f128) -> f128;
 /// [`f16::ceil`](../../std/primitive.f16.html#method.ceil)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn ceilf16(x: f16) -> f16;
+pub const unsafe fn ceilf16(x: f16) -> f16;
 /// Returns the smallest integer greater than or equal to an `f32`.
 ///
 /// The stabilized version of this intrinsic is
 /// [`f32::ceil`](../../std/primitive.f32.html#method.ceil)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn ceilf32(x: f32) -> f32;
+pub const unsafe fn ceilf32(x: f32) -> f32;
 /// Returns the smallest integer greater than or equal to an `f64`.
 ///
 /// The stabilized version of this intrinsic is
 /// [`f64::ceil`](../../std/primitive.f64.html#method.ceil)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn ceilf64(x: f64) -> f64;
+pub const unsafe fn ceilf64(x: f64) -> f64;
 /// Returns the smallest integer greater than or equal to an `f128`.
 ///
 /// The stabilized version of this intrinsic is
 /// [`f128::ceil`](../../std/primitive.f128.html#method.ceil)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn ceilf128(x: f128) -> f128;
+pub const unsafe fn ceilf128(x: f128) -> f128;
 
 /// Returns the integer part of an `f16`.
 ///
@@ -2270,28 +2298,28 @@ pub unsafe fn ceilf128(x: f128) -> f128;
 /// [`f16::trunc`](../../std/primitive.f16.html#method.trunc)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn truncf16(x: f16) -> f16;
+pub const unsafe fn truncf16(x: f16) -> f16;
 /// Returns the integer part of an `f32`.
 ///
 /// The stabilized version of this intrinsic is
 /// [`f32::trunc`](../../std/primitive.f32.html#method.trunc)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn truncf32(x: f32) -> f32;
+pub const unsafe fn truncf32(x: f32) -> f32;
 /// Returns the integer part of an `f64`.
 ///
 /// The stabilized version of this intrinsic is
 /// [`f64::trunc`](../../std/primitive.f64.html#method.trunc)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn truncf64(x: f64) -> f64;
+pub const unsafe fn truncf64(x: f64) -> f64;
 /// Returns the integer part of an `f128`.
 ///
 /// The stabilized version of this intrinsic is
 /// [`f128::trunc`](../../std/primitive.f128.html#method.trunc)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn truncf128(x: f128) -> f128;
+pub const unsafe fn truncf128(x: f128) -> f128;
 
 /// Returns the nearest integer to an `f16`. Rounds half-way cases to the number with an even
 /// least significant digit.
@@ -2300,7 +2328,7 @@ pub unsafe fn truncf128(x: f128) -> f128;
 /// [`f16::round_ties_even`](../../std/primitive.f16.html#method.round_ties_even)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub fn round_ties_even_f16(x: f16) -> f16;
+pub const fn round_ties_even_f16(x: f16) -> f16;
 
 /// Returns the nearest integer to an `f32`. Rounds half-way cases to the number with an even
 /// least significant digit.
@@ -2309,7 +2337,7 @@ pub fn round_ties_even_f16(x: f16) -> f16;
 /// [`f32::round_ties_even`](../../std/primitive.f32.html#method.round_ties_even)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub fn round_ties_even_f32(x: f32) -> f32;
+pub const fn round_ties_even_f32(x: f32) -> f32;
 
 /// Returns the nearest integer to an `f64`. Rounds half-way cases to the number with an even
 /// least significant digit.
@@ -2318,7 +2346,7 @@ pub fn round_ties_even_f32(x: f32) -> f32;
 /// [`f64::round_ties_even`](../../std/primitive.f64.html#method.round_ties_even)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub fn round_ties_even_f64(x: f64) -> f64;
+pub const fn round_ties_even_f64(x: f64) -> f64;
 
 /// Returns the nearest integer to an `f128`. Rounds half-way cases to the number with an even
 /// least significant digit.
@@ -2327,7 +2355,7 @@ pub fn round_ties_even_f64(x: f64) -> f64;
 /// [`f128::round_ties_even`](../../std/primitive.f128.html#method.round_ties_even)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub fn round_ties_even_f128(x: f128) -> f128;
+pub const fn round_ties_even_f128(x: f128) -> f128;
 
 /// Returns the nearest integer to an `f16`. Rounds half-way cases away from zero.
 ///
@@ -2335,28 +2363,28 @@ pub fn round_ties_even_f128(x: f128) -> f128;
 /// [`f16::round`](../../std/primitive.f16.html#method.round)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn roundf16(x: f16) -> f16;
+pub const unsafe fn roundf16(x: f16) -> f16;
 /// Returns the nearest integer to an `f32`. Rounds half-way cases away from zero.
 ///
 /// The stabilized version of this intrinsic is
 /// [`f32::round`](../../std/primitive.f32.html#method.round)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn roundf32(x: f32) -> f32;
+pub const unsafe fn roundf32(x: f32) -> f32;
 /// Returns the nearest integer to an `f64`. Rounds half-way cases away from zero.
 ///
 /// The stabilized version of this intrinsic is
 /// [`f64::round`](../../std/primitive.f64.html#method.round)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn roundf64(x: f64) -> f64;
+pub const unsafe fn roundf64(x: f64) -> f64;
 /// Returns the nearest integer to an `f128`. Rounds half-way cases away from zero.
 ///
 /// The stabilized version of this intrinsic is
 /// [`f128::round`](../../std/primitive.f128.html#method.round)
 #[rustc_intrinsic]
 #[rustc_nounwind]
-pub unsafe fn roundf128(x: f128) -> f128;
+pub const unsafe fn roundf128(x: f128) -> f128;
 
 /// Float addition that allows optimizations based on algebraic rules.
 /// May assume inputs are finite.
@@ -3575,18 +3603,9 @@ pub const fn type_id<T: ?Sized + 'static>() -> u128;
 #[unstable(feature = "core_intrinsics", issue = "none")]
 #[rustc_intrinsic_const_stable_indirect]
 #[rustc_intrinsic]
-pub const fn aggregate_raw_ptr<P: AggregateRawPtr<D, Metadata = M>, D, M>(data: D, meta: M) -> P;
-
-#[unstable(feature = "core_intrinsics", issue = "none")]
-pub trait AggregateRawPtr<D> {
-    type Metadata: Copy;
-}
-impl<P: ?Sized, T: ptr::Thin> AggregateRawPtr<*const T> for *const P {
-    type Metadata = <P as ptr::Pointee>::Metadata;
-}
-impl<P: ?Sized, T: ptr::Thin> AggregateRawPtr<*mut T> for *mut P {
-    type Metadata = <P as ptr::Pointee>::Metadata;
-}
+pub const fn aggregate_raw_ptr<P: bounds::BuiltinDeref, D, M>(data: D, meta: M) -> P
+where
+    <P as bounds::BuiltinDeref>::Pointee: ptr::Pointee<Metadata = M>;
 
 /// Lowers in MIR to `Rvalue::UnaryOp` with `UnOp::PtrMetadata`.
 ///
diff --git a/library/core/src/num/f128.rs b/library/core/src/num/f128.rs
index 0c2c4155d66c..6b9b2ba86891 100644
--- a/library/core/src/num/f128.rs
+++ b/library/core/src/num/f128.rs
@@ -1447,8 +1447,10 @@ impl f128 {
     #[inline]
     #[rustc_allow_incoherent_impl]
     #[unstable(feature = "f128", issue = "116909")]
+    #[rustc_const_unstable(feature = "f128", issue = "116909")]
+    // #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn floor(self) -> f128 {
+    pub const fn floor(self) -> f128 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::floorf128(self) }
     }
@@ -1477,8 +1479,10 @@ impl f128 {
     #[doc(alias = "ceiling")]
     #[rustc_allow_incoherent_impl]
     #[unstable(feature = "f128", issue = "116909")]
+    #[rustc_const_unstable(feature = "f128", issue = "116909")]
+    // #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn ceil(self) -> f128 {
+    pub const fn ceil(self) -> f128 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::ceilf128(self) }
     }
@@ -1513,8 +1517,10 @@ impl f128 {
     #[inline]
     #[rustc_allow_incoherent_impl]
     #[unstable(feature = "f128", issue = "116909")]
+    #[rustc_const_unstable(feature = "f128", issue = "116909")]
+    // #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn round(self) -> f128 {
+    pub const fn round(self) -> f128 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::roundf128(self) }
     }
@@ -1547,8 +1553,10 @@ impl f128 {
     #[inline]
     #[rustc_allow_incoherent_impl]
     #[unstable(feature = "f128", issue = "116909")]
+    #[rustc_const_unstable(feature = "f128", issue = "116909")]
+    // #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn round_ties_even(self) -> f128 {
+    pub const fn round_ties_even(self) -> f128 {
         intrinsics::round_ties_even_f128(self)
     }
 
@@ -1579,8 +1587,10 @@ impl f128 {
     #[doc(alias = "truncate")]
     #[rustc_allow_incoherent_impl]
     #[unstable(feature = "f128", issue = "116909")]
+    #[rustc_const_unstable(feature = "f128", issue = "116909")]
+    // #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn trunc(self) -> f128 {
+    pub const fn trunc(self) -> f128 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::truncf128(self) }
     }
@@ -1610,8 +1620,10 @@ impl f128 {
     #[inline]
     #[rustc_allow_incoherent_impl]
     #[unstable(feature = "f128", issue = "116909")]
+    #[rustc_const_unstable(feature = "f128", issue = "116909")]
+    // #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn fract(self) -> f128 {
+    pub const fn fract(self) -> f128 {
         self - self.trunc()
     }
 
diff --git a/library/core/src/num/f16.rs b/library/core/src/num/f16.rs
index 1a859f2277ff..eb7af993c60a 100644
--- a/library/core/src/num/f16.rs
+++ b/library/core/src/num/f16.rs
@@ -1423,8 +1423,10 @@ impl f16 {
     #[inline]
     #[rustc_allow_incoherent_impl]
     #[unstable(feature = "f16", issue = "116909")]
+    #[rustc_const_unstable(feature = "f16", issue = "116909")]
+    // #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn floor(self) -> f16 {
+    pub const fn floor(self) -> f16 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::floorf16(self) }
     }
@@ -1453,8 +1455,10 @@ impl f16 {
     #[doc(alias = "ceiling")]
     #[rustc_allow_incoherent_impl]
     #[unstable(feature = "f16", issue = "116909")]
+    #[rustc_const_unstable(feature = "f16", issue = "116909")]
+    // #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn ceil(self) -> f16 {
+    pub const fn ceil(self) -> f16 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::ceilf16(self) }
     }
@@ -1489,8 +1493,10 @@ impl f16 {
     #[inline]
     #[rustc_allow_incoherent_impl]
     #[unstable(feature = "f16", issue = "116909")]
+    #[rustc_const_unstable(feature = "f16", issue = "116909")]
+    // #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn round(self) -> f16 {
+    pub const fn round(self) -> f16 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::roundf16(self) }
     }
@@ -1523,8 +1529,10 @@ impl f16 {
     #[inline]
     #[rustc_allow_incoherent_impl]
     #[unstable(feature = "f16", issue = "116909")]
+    #[rustc_const_unstable(feature = "f16", issue = "116909")]
+    // #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn round_ties_even(self) -> f16 {
+    pub const fn round_ties_even(self) -> f16 {
         intrinsics::round_ties_even_f16(self)
     }
 
@@ -1555,8 +1563,10 @@ impl f16 {
     #[doc(alias = "truncate")]
     #[rustc_allow_incoherent_impl]
     #[unstable(feature = "f16", issue = "116909")]
+    #[rustc_const_unstable(feature = "f16", issue = "116909")]
+    // #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn trunc(self) -> f16 {
+    pub const fn trunc(self) -> f16 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::truncf16(self) }
     }
@@ -1586,8 +1596,10 @@ impl f16 {
     #[inline]
     #[rustc_allow_incoherent_impl]
     #[unstable(feature = "f16", issue = "116909")]
+    #[rustc_const_unstable(feature = "f16", issue = "116909")]
+    // #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn fract(self) -> f16 {
+    pub const fn fract(self) -> f16 {
         self - self.trunc()
     }
 
diff --git a/library/core/src/num/f32.rs b/library/core/src/num/f32.rs
index 6636054a659b..bf923d4070ad 100644
--- a/library/core/src/num/f32.rs
+++ b/library/core/src/num/f32.rs
@@ -1591,8 +1591,9 @@ pub mod math {
     /// [`f32::floor`]: ../../../std/primitive.f32.html#method.floor
     #[inline]
     #[unstable(feature = "core_float_math", issue = "137578")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn floor(x: f32) -> f32 {
+    pub const fn floor(x: f32) -> f32 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::floorf32(x) }
     }
@@ -1621,7 +1622,8 @@ pub mod math {
     #[doc(alias = "ceiling")]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[unstable(feature = "core_float_math", issue = "137578")]
-    pub fn ceil(x: f32) -> f32 {
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    pub const fn ceil(x: f32) -> f32 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::ceilf32(x) }
     }
@@ -1655,7 +1657,8 @@ pub mod math {
     #[inline]
     #[unstable(feature = "core_float_math", issue = "137578")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn round(x: f32) -> f32 {
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    pub const fn round(x: f32) -> f32 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::roundf32(x) }
     }
@@ -1688,7 +1691,8 @@ pub mod math {
     #[inline]
     #[unstable(feature = "core_float_math", issue = "137578")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn round_ties_even(x: f32) -> f32 {
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    pub const fn round_ties_even(x: f32) -> f32 {
         intrinsics::round_ties_even_f32(x)
     }
 
@@ -1718,7 +1722,8 @@ pub mod math {
     #[doc(alias = "truncate")]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[unstable(feature = "core_float_math", issue = "137578")]
-    pub fn trunc(x: f32) -> f32 {
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    pub const fn trunc(x: f32) -> f32 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::truncf32(x) }
     }
@@ -1747,8 +1752,9 @@ pub mod math {
     /// [`f32::fract`]: ../../../std/primitive.f32.html#method.fract
     #[inline]
     #[unstable(feature = "core_float_math", issue = "137578")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn fract(x: f32) -> f32 {
+    pub const fn fract(x: f32) -> f32 {
         x - trunc(x)
     }
 
diff --git a/library/core/src/num/f64.rs b/library/core/src/num/f64.rs
index 8fbf2cffbaf4..0a63ed828aed 100644
--- a/library/core/src/num/f64.rs
+++ b/library/core/src/num/f64.rs
@@ -1589,8 +1589,9 @@ pub mod math {
     /// [`f64::floor`]: ../../../std/primitive.f64.html#method.floor
     #[inline]
     #[unstable(feature = "core_float_math", issue = "137578")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn floor(x: f64) -> f64 {
+    pub const fn floor(x: f64) -> f64 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::floorf64(x) }
     }
@@ -1618,8 +1619,9 @@ pub mod math {
     #[inline]
     #[doc(alias = "ceiling")]
     #[unstable(feature = "core_float_math", issue = "137578")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn ceil(x: f64) -> f64 {
+    pub const fn ceil(x: f64) -> f64 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::ceilf64(x) }
     }
@@ -1652,8 +1654,9 @@ pub mod math {
     /// [`f64::round`]: ../../../std/primitive.f64.html#method.round
     #[inline]
     #[unstable(feature = "core_float_math", issue = "137578")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn round(x: f64) -> f64 {
+    pub const fn round(x: f64) -> f64 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::roundf64(x) }
     }
@@ -1685,8 +1688,9 @@ pub mod math {
     /// [`f64::round_ties_even`]: ../../../std/primitive.f64.html#method.round_ties_even
     #[inline]
     #[unstable(feature = "core_float_math", issue = "137578")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn round_ties_even(x: f64) -> f64 {
+    pub const fn round_ties_even(x: f64) -> f64 {
         intrinsics::round_ties_even_f64(x)
     }
 
@@ -1715,8 +1719,9 @@ pub mod math {
     #[inline]
     #[doc(alias = "truncate")]
     #[unstable(feature = "core_float_math", issue = "137578")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn trunc(x: f64) -> f64 {
+    pub const fn trunc(x: f64) -> f64 {
         // SAFETY: intrinsic with no preconditions
         unsafe { intrinsics::truncf64(x) }
     }
@@ -1745,8 +1750,9 @@ pub mod math {
     /// [`f64::fract`]: ../../../std/primitive.f64.html#method.fract
     #[inline]
     #[unstable(feature = "core_float_math", issue = "137578")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    pub fn fract(x: f64) -> f64 {
+    pub const fn fract(x: f64) -> f64 {
         x - trunc(x)
     }
 
diff --git a/library/core/src/result.rs b/library/core/src/result.rs
index ef2da5e8fbf4..23e32c2e0f01 100644
--- a/library/core/src/result.rs
+++ b/library/core/src/result.rs
@@ -1722,7 +1722,6 @@ impl<T, E> Result<Result<T, E>, E> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(result_flattening)]
     /// let x: Result<Result<&'static str, u32>, u32> = Ok(Ok("hello"));
     /// assert_eq!(Ok("hello"), x.flatten());
     ///
@@ -1736,14 +1735,14 @@ impl<T, E> Result<Result<T, E>, E> {
     /// Flattening only removes one level of nesting at a time:
     ///
     /// ```
-    /// #![feature(result_flattening)]
     /// let x: Result<Result<Result<&'static str, u32>, u32>, u32> = Ok(Ok(Ok("hello")));
     /// assert_eq!(Ok(Ok("hello")), x.flatten());
     /// assert_eq!(Ok("hello"), x.flatten().flatten());
     /// ```
     #[inline]
-    #[unstable(feature = "result_flattening", issue = "70142")]
-    #[rustc_const_unstable(feature = "result_flattening", issue = "70142")]
+    #[stable(feature = "result_flattening", since = "CURRENT_RUSTC_VERSION")]
+    #[rustc_allow_const_fn_unstable(const_precise_live_drops)]
+    #[rustc_const_stable(feature = "result_flattening", since = "CURRENT_RUSTC_VERSION")]
     pub const fn flatten(self) -> Result<T, E> {
         // FIXME(const-hack): could be written with `and_then`
         match self {
diff --git a/library/core/src/slice/index.rs b/library/core/src/slice/index.rs
index b18d316c73a6..69160a911b21 100644
--- a/library/core/src/slice/index.rs
+++ b/library/core/src/slice/index.rs
@@ -1,5 +1,7 @@
 //! Indexing implementations for `[T]`.
 
+#[cfg(not(bootstrap))]
+use crate::intrinsics::slice_get_unchecked;
 use crate::panic::const_panic;
 use crate::ub_checks::assert_unsafe_precondition;
 use crate::{ops, range};
@@ -83,6 +85,7 @@ const fn slice_end_index_overflow_fail() -> ! {
 // Both the safe and unsafe public methods share these helpers,
 // which use intrinsics directly to get *no* extra checks.
 
+#[cfg(bootstrap)]
 #[inline(always)]
 const unsafe fn get_noubcheck<T>(ptr: *const [T], index: usize) -> *const T {
     let ptr = ptr as *const T;
@@ -90,6 +93,7 @@ const unsafe fn get_noubcheck<T>(ptr: *const [T], index: usize) -> *const T {
     unsafe { crate::intrinsics::offset(ptr, index) }
 }
 
+#[cfg(bootstrap)]
 #[inline(always)]
 const unsafe fn get_mut_noubcheck<T>(ptr: *mut [T], index: usize) -> *mut T {
     let ptr = ptr as *mut T;
@@ -103,8 +107,9 @@ const unsafe fn get_offset_len_noubcheck<T>(
     offset: usize,
     len: usize,
 ) -> *const [T] {
+    let ptr = ptr as *const T;
     // SAFETY: The caller already checked these preconditions
-    let ptr = unsafe { get_noubcheck(ptr, offset) };
+    let ptr = unsafe { crate::intrinsics::offset(ptr, offset) };
     crate::intrinsics::aggregate_raw_ptr(ptr, len)
 }
 
@@ -114,8 +119,9 @@ const unsafe fn get_offset_len_mut_noubcheck<T>(
     offset: usize,
     len: usize,
 ) -> *mut [T] {
+    let ptr = ptr as *mut T;
     // SAFETY: The caller already checked these preconditions
-    let ptr = unsafe { get_mut_noubcheck(ptr, offset) };
+    let ptr = unsafe { crate::intrinsics::offset(ptr, offset) };
     crate::intrinsics::aggregate_raw_ptr(ptr, len)
 }
 
@@ -224,15 +230,35 @@ unsafe impl<T> SliceIndex<[T]> for usize {
 
     #[inline]
     fn get(self, slice: &[T]) -> Option<&T> {
-        // SAFETY: `self` is checked to be in bounds.
-        if self < slice.len() { unsafe { Some(&*get_noubcheck(slice, self)) } } else { None }
+        if self < slice.len() {
+            #[cfg(bootstrap)]
+            // SAFETY: `self` is checked to be in bounds.
+            unsafe {
+                Some(&*get_noubcheck(slice, self))
+            }
+            #[cfg(not(bootstrap))]
+            // SAFETY: `self` is checked to be in bounds.
+            unsafe {
+                Some(slice_get_unchecked(slice, self))
+            }
+        } else {
+            None
+        }
     }
 
     #[inline]
     fn get_mut(self, slice: &mut [T]) -> Option<&mut T> {
         if self < slice.len() {
+            #[cfg(bootstrap)]
             // SAFETY: `self` is checked to be in bounds.
-            unsafe { Some(&mut *get_mut_noubcheck(slice, self)) }
+            unsafe {
+                Some(&mut *get_mut_noubcheck(slice, self))
+            }
+            #[cfg(not(bootstrap))]
+            // SAFETY: `self` is checked to be in bounds.
+            unsafe {
+                Some(slice_get_unchecked(slice, self))
+            }
         } else {
             None
         }
@@ -254,7 +280,14 @@ unsafe impl<T> SliceIndex<[T]> for usize {
             // Use intrinsics::assume instead of hint::assert_unchecked so that we don't check the
             // precondition of this function twice.
             crate::intrinsics::assume(self < slice.len());
-            get_noubcheck(slice, self)
+            #[cfg(bootstrap)]
+            {
+                get_noubcheck(slice, self)
+            }
+            #[cfg(not(bootstrap))]
+            {
+                slice_get_unchecked(slice, self)
+            }
         }
     }
 
@@ -267,7 +300,16 @@ unsafe impl<T> SliceIndex<[T]> for usize {
             (this: usize = self, len: usize = slice.len()) => this < len
         );
         // SAFETY: see comments for `get_unchecked` above.
-        unsafe { get_mut_noubcheck(slice, self) }
+        unsafe {
+            #[cfg(bootstrap)]
+            {
+                get_mut_noubcheck(slice, self)
+            }
+            #[cfg(not(bootstrap))]
+            {
+                slice_get_unchecked(slice, self)
+            }
+        }
     }
 
     #[inline]
diff --git a/library/core/src/str/converts.rs b/library/core/src/str/converts.rs
index 058628797ea8..6da9dce2d870 100644
--- a/library/core/src/str/converts.rs
+++ b/library/core/src/str/converts.rs
@@ -6,6 +6,8 @@ use crate::{mem, ptr};
 
 /// Converts a slice of bytes to a string slice.
 ///
+/// This is an alias to [`str::from_utf8`].
+///
 /// A string slice ([`&str`]) is made of bytes ([`u8`]), and a byte slice
 /// ([`&[u8]`][byteslice]) is made of bytes, so this function converts between
 /// the two. Not all byte slices are valid string slices, however: [`&str`] requires
@@ -97,6 +99,8 @@ pub const fn from_utf8(v: &[u8]) -> Result<&str, Utf8Error> {
 
 /// Converts a mutable slice of bytes to a mutable string slice.
 ///
+/// This is an alias to [`str::from_utf8_mut`].
+///
 /// # Examples
 ///
 /// Basic usage:
@@ -142,6 +146,8 @@ pub const fn from_utf8_mut(v: &mut [u8]) -> Result<&mut str, Utf8Error> {
 /// Converts a slice of bytes to a string slice without checking
 /// that the string contains valid UTF-8.
 ///
+/// This is an alias to [`str::from_utf8_unchecked`].
+///
 /// See the safe version, [`from_utf8`], for more information.
 ///
 /// # Safety
@@ -178,6 +184,8 @@ pub const unsafe fn from_utf8_unchecked(v: &[u8]) -> &str {
 /// Converts a slice of bytes to a string slice without checking
 /// that the string contains valid UTF-8; mutable version.
 ///
+/// This is an alias to [`str::from_utf8_unchecked_mut`].
+///
 /// See the immutable version, [`from_utf8_unchecked()`] for documentation and safety requirements.
 ///
 /// # Examples
diff --git a/library/coretests/tests/lib.rs b/library/coretests/tests/lib.rs
index 693b14ef7620..dd7cdd79c0d6 100644
--- a/library/coretests/tests/lib.rs
+++ b/library/coretests/tests/lib.rs
@@ -16,6 +16,7 @@
 #![feature(char_max_len)]
 #![feature(clone_to_uninit)]
 #![feature(const_eval_select)]
+#![feature(const_float_round_methods)]
 #![feature(const_trait_impl)]
 #![feature(core_float_math)]
 #![feature(core_intrinsics)]
diff --git a/library/coretests/tests/num/mod.rs b/library/coretests/tests/num/mod.rs
index 1212d36a1b15..fa05bbdd9b77 100644
--- a/library/coretests/tests/num/mod.rs
+++ b/library/coretests/tests/num/mod.rs
@@ -731,6 +731,9 @@ assume_usize_width! {
     }
 }
 
+// FIXME(141726): there is a lot of duplication between the following tests and
+// the tests in `coretests/tests/floats/f*.rs`
+// See issue https://github.com/rust-lang/rust/issues/141726 for more details.
 macro_rules! test_float {
     ($modname: ident, $fassert: ident, $fty: ty) => {
         mod $modname {
@@ -947,6 +950,117 @@ macro_rules! test_float {
                 assert!(<$fty>::INFINITY.div_euclid(<$fty>::NAN).is_nan());
                 assert!(<$fty>::NAN.div_euclid(<$fty>::INFINITY).is_nan());
             }
+            #[test]
+            #[cfg(not(bootstrap))]
+            fn floor() {
+                $fassert!((0.0 as $fty).floor(), 0.0);
+                $fassert!((0.0 as $fty).floor().is_sign_positive());
+                $fassert!((-0.0 as $fty).floor(), -0.0);
+                $fassert!((-0.0 as $fty).floor().is_sign_negative());
+                $fassert!((0.5 as $fty).floor(), 0.0);
+                $fassert!((-0.5 as $fty).floor(), -1.0);
+                $fassert!((1.5 as $fty).floor(), 1.0);
+                $fassert!(<$fty>::MAX.floor(), <$fty>::MAX);
+                $fassert!(<$fty>::MIN.floor(), <$fty>::MIN);
+                $fassert!(<$fty>::MIN_POSITIVE.floor(), 0.0);
+                $fassert!((-<$fty>::MIN_POSITIVE).floor(), -1.0);
+                $fassert!(<$fty>::NAN.floor().is_nan());
+                $fassert!(<$fty>::INFINITY.floor(), <$fty>::INFINITY);
+                $fassert!(<$fty>::NEG_INFINITY.floor(), <$fty>::NEG_INFINITY);
+            }
+            #[test]
+            #[cfg(not(bootstrap))]
+            fn ceil() {
+                $fassert!((0.0 as $fty).ceil(), 0.0);
+                $fassert!((0.0 as $fty).ceil().is_sign_positive());
+                $fassert!((-0.0 as $fty).ceil(), 0.0);
+                $fassert!((-0.0 as $fty).ceil().is_sign_negative());
+                $fassert!((0.5 as $fty).ceil(), 1.0);
+                $fassert!((-0.5 as $fty).ceil(), 0.0);
+                $fassert!(<$fty>::MAX.ceil(), <$fty>::MAX);
+                $fassert!(<$fty>::MIN.ceil(), <$fty>::MIN);
+                $fassert!(<$fty>::MIN_POSITIVE.ceil(), 1.0);
+                $fassert!((-<$fty>::MIN_POSITIVE).ceil(), 0.0);
+                $fassert!(<$fty>::NAN.ceil().is_nan());
+                $fassert!(<$fty>::INFINITY.ceil(), <$fty>::INFINITY);
+                $fassert!(<$fty>::NEG_INFINITY.ceil(), <$fty>::NEG_INFINITY);
+            }
+            #[test]
+            #[cfg(not(bootstrap))]
+            fn round() {
+                $fassert!((0.0 as $fty).round(), 0.0);
+                $fassert!((0.0 as $fty).round().is_sign_positive());
+                $fassert!((-0.0 as $fty).round(), -0.0);
+                $fassert!((-0.0 as $fty).round().is_sign_negative());
+                $fassert!((0.5 as $fty).round(), 1.0);
+                $fassert!((-0.5 as $fty).round(), -1.0);
+                $fassert!(<$fty>::MAX.round(), <$fty>::MAX);
+                $fassert!(<$fty>::MIN.round(), <$fty>::MIN);
+                $fassert!(<$fty>::MIN_POSITIVE.round(), 0.0);
+                $fassert!((-<$fty>::MIN_POSITIVE).round(), 0.0);
+                $fassert!(<$fty>::NAN.round().is_nan());
+                $fassert!(<$fty>::INFINITY.round(), <$fty>::INFINITY);
+                $fassert!(<$fty>::NEG_INFINITY.round(), <$fty>::NEG_INFINITY);
+            }
+            #[test]
+            #[cfg(not(bootstrap))]
+            fn round_ties_even() {
+                $fassert!((0.0 as $fty).round_ties_even(), 0.0);
+                $fassert!((0.0 as $fty).round_ties_even().is_sign_positive());
+                $fassert!((-0.0 as $fty).round_ties_even(), -0.0);
+                $fassert!((-0.0 as $fty).round_ties_even().is_sign_negative());
+                $fassert!((0.5 as $fty).round_ties_even(), 0.0);
+                $fassert!((0.5 as $fty).round_ties_even().is_sign_positive());
+                $fassert!((-0.5 as $fty).round_ties_even(), -0.0);
+                $fassert!((-0.5 as $fty).round_ties_even().is_sign_negative());
+                $fassert!(<$fty>::MAX.round_ties_even(), <$fty>::MAX);
+                $fassert!(<$fty>::MIN.round_ties_even(), <$fty>::MIN);
+                $fassert!(<$fty>::MIN_POSITIVE.round_ties_even(), 0.0);
+                $fassert!((-<$fty>::MIN_POSITIVE).round_ties_even(), 0.0);
+                $fassert!(<$fty>::NAN.round_ties_even().is_nan());
+                $fassert!(<$fty>::INFINITY.round_ties_even(), <$fty>::INFINITY);
+                $fassert!(<$fty>::NEG_INFINITY.round_ties_even(), <$fty>::NEG_INFINITY);
+            }
+            #[test]
+            #[cfg(not(bootstrap))]
+            fn trunc() {
+                $fassert!((0.0 as $fty).trunc(), 0.0);
+                $fassert!((0.0 as $fty).trunc().is_sign_positive());
+                $fassert!((-0.0 as $fty).trunc(), -0.0);
+                $fassert!((-0.0 as $fty).trunc().is_sign_negative());
+                $fassert!((0.5 as $fty).trunc(), 0.0);
+                $fassert!((0.5 as $fty).trunc().is_sign_positive());
+                $fassert!((-0.5 as $fty).trunc(), -0.0);
+                $fassert!((-0.5 as $fty).trunc().is_sign_negative());
+                $fassert!(<$fty>::MAX.trunc(), <$fty>::MAX);
+                $fassert!(<$fty>::MIN.trunc(), <$fty>::MIN);
+                $fassert!(<$fty>::MIN_POSITIVE.trunc(), 0.0);
+                $fassert!((-<$fty>::MIN_POSITIVE).trunc(), 0.0);
+                $fassert!(<$fty>::NAN.trunc().is_nan());
+                $fassert!(<$fty>::INFINITY.trunc(), <$fty>::INFINITY);
+                $fassert!(<$fty>::NEG_INFINITY.trunc(), <$fty>::NEG_INFINITY);
+            }
+            #[test]
+            #[cfg(not(bootstrap))]
+            fn fract() {
+                $fassert!((0.0 as $fty).fract(), 0.0);
+                $fassert!((0.0 as $fty).fract().is_sign_positive());
+                $fassert!((-0.0 as $fty).fract(), 0.0);
+                $fassert!((-0.0 as $fty).fract().is_sign_positive());
+                $fassert!((0.5 as $fty).fract(), 0.5);
+                $fassert!((0.5 as $fty).fract().is_sign_positive());
+                $fassert!((-0.5 as $fty).fract(), -0.5);
+                $fassert!((-0.5 as $fty).fract().is_sign_negative());
+                $fassert!(<$fty>::MAX.fract(), 0.0);
+                $fassert!(<$fty>::MIN.fract(), 0.0);
+                $fassert!(<$fty>::MIN_POSITIVE.fract(), <$fty>::MIN_POSITIVE);
+                $fassert!(<$fty>::MIN_POSITIVE.fract().is_sign_positive());
+                $fassert!((-<$fty>::MIN_POSITIVE).fract(), -<$fty>::MIN_POSITIVE);
+                $fassert!((-<$fty>::MIN_POSITIVE).fract().is_sign_negative());
+                $fassert!(<$fty>::NAN.fract().is_nan());
+                $fassert!(<$fty>::INFINITY.fract().is_nan());
+                $fassert!(<$fty>::NEG_INFINITY.fract().is_nan());
+            }
         }
     };
 }
diff --git a/library/std/Cargo.toml b/library/std/Cargo.toml
index 4ff4895ecde7..31371f06b386 100644
--- a/library/std/Cargo.toml
+++ b/library/std/Cargo.toml
@@ -18,7 +18,7 @@ cfg-if = { version = "1.0", features = ['rustc-dep-of-std'] }
 panic_unwind = { path = "../panic_unwind", optional = true }
 panic_abort = { path = "../panic_abort" }
 core = { path = "../core", public = true }
-compiler_builtins = { version = "=0.1.159" }
+compiler_builtins = { version = "=0.1.160" }
 unwind = { path = "../unwind" }
 hashbrown = { version = "0.15", default-features = false, features = [
     'rustc-dep-of-std',
diff --git a/library/std/src/fs.rs b/library/std/src/fs.rs
index 8ed5800e9d06..711efc7d011c 100644
--- a/library/std/src/fs.rs
+++ b/library/std/src/fs.rs
@@ -2915,17 +2915,28 @@ pub fn remove_dir<P: AsRef<Path>>(path: P) -> io::Result<()> {
 ///
 /// # Platform-specific behavior
 ///
-/// This function currently corresponds to `openat`, `fdopendir`, `unlinkat` and `lstat` functions
-/// on Unix (except for REDOX) and the `CreateFileW`, `GetFileInformationByHandleEx`,
-/// `SetFileInformationByHandle`, and `NtCreateFile` functions on Windows. Note that, this
-/// [may change in the future][changes].
+/// These implementation details [may change in the future][changes].
+///
+/// - "Unix-like": By default, this function currently corresponds to
+/// `openat`, `fdopendir`, `unlinkat` and `lstat`
+/// on Unix-family platforms, except where noted otherwise.
+/// - "Windows": This function currently corresponds to `CreateFileW`,
+/// `GetFileInformationByHandleEx`, `SetFileInformationByHandle`, and `NtCreateFile`.
+///
+/// ## Time-of-check to time-of-use (TOCTOU) race conditions
+/// On a few platforms there is no way to remove a directory's contents without following symlinks
+/// unless you perform a check and then operate on paths based on that directory.
+/// This allows concurrently-running code to replace the directory with a symlink after the check,
+/// causing a removal to instead operate on a path based on the symlink. This is a TOCTOU race.
+/// By default, `fs::remove_dir_all` protects against a symlink TOCTOU race on all platforms
+/// except the following. It should not be used in security-sensitive contexts on these platforms:
+/// - Miri: Even when emulating targets where the underlying implementation will protect against
+/// TOCTOU races, Miri will not do so.
+/// - Redox OS: This function does not protect against TOCTOU races, as Redox does not implement
+/// the required platform support to do so.
 ///
 /// [changes]: io#platform-specific-behavior
 ///
-/// On REDOX, as well as when running in Miri for any target, this function is not protected against
-/// time-of-check to time-of-use (TOCTOU) race conditions, and should not be used in
-/// security-sensitive code on those platforms. All other platforms are protected.
-///
 /// # Errors
 ///
 /// See [`fs::remove_file`] and [`fs::remove_dir`].
diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs
index a3f0f3cc55a1..74a343398602 100644
--- a/library/std/src/lib.rs
+++ b/library/std/src/lib.rs
@@ -335,6 +335,7 @@
 #![feature(bstr_internals)]
 #![feature(char_internals)]
 #![feature(clone_to_uninit)]
+#![feature(const_float_round_methods)]
 #![feature(core_intrinsics)]
 #![feature(core_io_borrowed_buf)]
 #![feature(duration_constants)]
diff --git a/library/std/src/num/f32.rs b/library/std/src/num/f32.rs
index 5210e75ec453..b7f6529ac402 100644
--- a/library/std/src/num/f32.rs
+++ b/library/std/src/num/f32.rs
@@ -44,8 +44,9 @@ impl f32 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[inline]
-    pub fn floor(self) -> f32 {
+    pub const fn floor(self) -> f32 {
         core::f32::math::floor(self)
     }
 
@@ -66,8 +67,9 @@ impl f32 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[inline]
-    pub fn ceil(self) -> f32 {
+    pub const fn ceil(self) -> f32 {
         core::f32::math::ceil(self)
     }
 
@@ -94,8 +96,9 @@ impl f32 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[inline]
-    pub fn round(self) -> f32 {
+    pub const fn round(self) -> f32 {
         core::f32::math::round(self)
     }
 
@@ -120,8 +123,9 @@ impl f32 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "round_ties_even", since = "1.77.0")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[inline]
-    pub fn round_ties_even(self) -> f32 {
+    pub const fn round_ties_even(self) -> f32 {
         core::f32::math::round_ties_even(self)
     }
 
@@ -145,8 +149,9 @@ impl f32 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[inline]
-    pub fn trunc(self) -> f32 {
+    pub const fn trunc(self) -> f32 {
         core::f32::math::trunc(self)
     }
 
@@ -168,8 +173,9 @@ impl f32 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[inline]
-    pub fn fract(self) -> f32 {
+    pub const fn fract(self) -> f32 {
         core::f32::math::fract(self)
     }
 
diff --git a/library/std/src/num/f64.rs b/library/std/src/num/f64.rs
index f837800d6634..75e35a8db335 100644
--- a/library/std/src/num/f64.rs
+++ b/library/std/src/num/f64.rs
@@ -44,8 +44,9 @@ impl f64 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[inline]
-    pub fn floor(self) -> f64 {
+    pub const fn floor(self) -> f64 {
         core::f64::math::floor(self)
     }
 
@@ -66,8 +67,9 @@ impl f64 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[inline]
-    pub fn ceil(self) -> f64 {
+    pub const fn ceil(self) -> f64 {
         core::f64::math::ceil(self)
     }
 
@@ -94,8 +96,9 @@ impl f64 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[inline]
-    pub fn round(self) -> f64 {
+    pub const fn round(self) -> f64 {
         core::f64::math::round(self)
     }
 
@@ -120,8 +123,9 @@ impl f64 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "round_ties_even", since = "1.77.0")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[inline]
-    pub fn round_ties_even(self) -> f64 {
+    pub const fn round_ties_even(self) -> f64 {
         core::f64::math::round_ties_even(self)
     }
 
@@ -145,8 +149,9 @@ impl f64 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[inline]
-    pub fn trunc(self) -> f64 {
+    pub const fn trunc(self) -> f64 {
         core::f64::math::trunc(self)
     }
 
@@ -168,8 +173,9 @@ impl f64 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
     #[inline]
-    pub fn fract(self) -> f64 {
+    pub const fn fract(self) -> f64 {
         core::f64::math::fract(self)
     }
 
diff --git a/library/std/src/sys/thread_local/native/lazy.rs b/library/std/src/sys/thread_local/native/lazy.rs
index 51294285ba01..b556dd9aa25e 100644
--- a/library/std/src/sys/thread_local/native/lazy.rs
+++ b/library/std/src/sys/thread_local/native/lazy.rs
@@ -1,9 +1,9 @@
-use crate::cell::UnsafeCell;
-use crate::hint::unreachable_unchecked;
+use crate::cell::{Cell, UnsafeCell};
+use crate::mem::MaybeUninit;
 use crate::ptr;
 use crate::sys::thread_local::{abort_on_dtor_unwind, destructors};
 
-pub unsafe trait DestroyedState: Sized {
+pub unsafe trait DestroyedState: Sized + Copy {
     fn register_dtor<T>(s: &Storage<T, Self>);
 }
 
@@ -19,15 +19,17 @@ unsafe impl DestroyedState for () {
     }
 }
 
-enum State<T, D> {
-    Initial,
-    Alive(T),
+#[derive(Copy, Clone)]
+enum State<D> {
+    Uninitialized,
+    Alive,
     Destroyed(D),
 }
 
 #[allow(missing_debug_implementations)]
 pub struct Storage<T, D> {
-    state: UnsafeCell<State<T, D>>,
+    state: Cell<State<D>>,
+    value: UnsafeCell<MaybeUninit<T>>,
 }
 
 impl<T, D> Storage<T, D>
@@ -35,7 +37,10 @@ where
     D: DestroyedState,
 {
     pub const fn new() -> Storage<T, D> {
-        Storage { state: UnsafeCell::new(State::Initial) }
+        Storage {
+            state: Cell::new(State::Uninitialized),
+            value: UnsafeCell::new(MaybeUninit::uninit()),
+        }
     }
 
     /// Gets a pointer to the TLS value, potentially initializing it with the
@@ -49,35 +54,49 @@ where
     /// The `self` reference must remain valid until the TLS destructor is run.
     #[inline]
     pub unsafe fn get_or_init(&self, i: Option<&mut Option<T>>, f: impl FnOnce() -> T) -> *const T {
-        let state = unsafe { &*self.state.get() };
-        match state {
-            State::Alive(v) => v,
-            State::Destroyed(_) => ptr::null(),
-            State::Initial => unsafe { self.initialize(i, f) },
+        if let State::Alive = self.state.get() {
+            self.value.get().cast()
+        } else {
+            unsafe { self.get_or_init_slow(i, f) }
         }
     }
 
+    /// # Safety
+    /// The `self` reference must remain valid until the TLS destructor is run.
     #[cold]
-    unsafe fn initialize(&self, i: Option<&mut Option<T>>, f: impl FnOnce() -> T) -> *const T {
-        // Perform initialization
+    unsafe fn get_or_init_slow(
+        &self,
+        i: Option<&mut Option<T>>,
+        f: impl FnOnce() -> T,
+    ) -> *const T {
+        match self.state.get() {
+            State::Uninitialized => {}
+            State::Alive => return self.value.get().cast(),
+            State::Destroyed(_) => return ptr::null(),
+        }
 
         let v = i.and_then(Option::take).unwrap_or_else(f);
 
-        let old = unsafe { self.state.get().replace(State::Alive(v)) };
-        match old {
+        // SAFETY: we cannot be inside a `LocalKey::with` scope, as the initializer
+        // has already returned and the next scope only starts after we return
+        // the pointer. Therefore, there can be no references to the old value,
+        // even if it was initialized. Thus because we are !Sync we have exclusive
+        // access to self.value and may replace it.
+        let mut old_value = unsafe { self.value.get().replace(MaybeUninit::new(v)) };
+        match self.state.replace(State::Alive) {
             // If the variable is not being recursively initialized, register
             // the destructor. This might be a noop if the value does not need
             // destruction.
-            State::Initial => D::register_dtor(self),
-            // Else, drop the old value. This might be changed to a panic.
-            val => drop(val),
+            State::Uninitialized => D::register_dtor(self),
+
+            // Recursive initialization, we only need to drop the old value
+            // as we've already registered the destructor.
+            State::Alive => unsafe { old_value.assume_init_drop() },
+
+            State::Destroyed(_) => unreachable!(),
         }
 
-        // SAFETY: the state was just set to `Alive`
-        unsafe {
-            let State::Alive(v) = &*self.state.get() else { unreachable_unchecked() };
-            v
-        }
+        self.value.get().cast()
     }
 }
 
@@ -92,9 +111,12 @@ unsafe extern "C" fn destroy<T>(ptr: *mut u8) {
     // Print a nice abort message if a panic occurs.
     abort_on_dtor_unwind(|| {
         let storage = unsafe { &*(ptr as *const Storage<T, ()>) };
-        // Update the state before running the destructor as it may attempt to
-        // access the variable.
-        let val = unsafe { storage.state.get().replace(State::Destroyed(())) };
-        drop(val);
+        if let State::Alive = storage.state.replace(State::Destroyed(())) {
+            // SAFETY: we ensured the state was Alive so the value was initialized.
+            // We also updated the state to Destroyed to prevent the destructor
+            // from accessing the thread-local variable, as this would violate
+            // the exclusive access provided by &mut T in Drop::drop.
+            unsafe { (*storage.value.get()).assume_init_drop() }
+        }
     })
 }
diff --git a/src/bootstrap/src/core/build_steps/compile.rs b/src/bootstrap/src/core/build_steps/compile.rs
index d5ea96b43f56..8668550bddf3 100644
--- a/src/bootstrap/src/core/build_steps/compile.rs
+++ b/src/bootstrap/src/core/build_steps/compile.rs
@@ -1409,7 +1409,7 @@ fn rustc_llvm_env(builder: &Builder<'_>, cargo: &mut Cargo, target: TargetSelect
         cargo.env("LLVM_LINKER_FLAGS", llvm_linker_flags);
     }
 
-    // Building with a static libstdc++ is only supported on linux right now,
+    // Building with a static libstdc++ is only supported on Linux and windows-gnu* right now,
     // not for MSVC or macOS
     if builder.config.llvm_static_stdcpp
         && !target.contains("freebsd")
@@ -1417,12 +1417,14 @@ fn rustc_llvm_env(builder: &Builder<'_>, cargo: &mut Cargo, target: TargetSelect
         && !target.contains("apple")
         && !target.contains("solaris")
     {
+        let libstdcxx_name =
+            if target.contains("windows-gnullvm") { "libc++.a" } else { "libstdc++.a" };
         let file = compiler_file(
             builder,
             &builder.cxx(target).unwrap(),
             target,
             CLang::Cxx,
-            "libstdc++.a",
+            libstdcxx_name,
         );
         cargo.env("LLVM_STATIC_STDCPP", file);
     }
diff --git a/src/bootstrap/src/core/build_steps/llvm.rs b/src/bootstrap/src/core/build_steps/llvm.rs
index 5e4a1c7d9f07..979ff3992672 100644
--- a/src/bootstrap/src/core/build_steps/llvm.rs
+++ b/src/bootstrap/src/core/build_steps/llvm.rs
@@ -285,7 +285,8 @@ impl Step for Llvm {
             LlvmBuildStatus::ShouldBuild(m) => m,
         };
 
-        if builder.llvm_link_shared() && target.is_windows() {
+        if builder.llvm_link_shared() && target.is_windows() && !target.ends_with("windows-gnullvm")
+        {
             panic!("shared linking to LLVM is not currently supported on {}", target.triple);
         }
 
diff --git a/src/build_helper/src/lib.rs b/src/build_helper/src/lib.rs
index 7e580db48aa9..1f5cf7236411 100644
--- a/src/build_helper/src/lib.rs
+++ b/src/build_helper/src/lib.rs
@@ -29,4 +29,5 @@ pub const RUSTC_PGO_CRATES: &[&str] = &[
     "tuple-stress",
     "diesel-2.2.10",
     "bitmaps-3.2.1",
+    "serde-1.0.219-new-solver",
 ];
diff --git a/src/ci/docker/host-x86_64/x86_64-gnu-tools/checktools.sh b/src/ci/docker/host-x86_64/x86_64-gnu-tools/checktools.sh
index 9222710b8437..62e0451814b3 100755
--- a/src/ci/docker/host-x86_64/x86_64-gnu-tools/checktools.sh
+++ b/src/ci/docker/host-x86_64/x86_64-gnu-tools/checktools.sh
@@ -53,8 +53,8 @@ MIRIFLAGS="-Zmiri-force-intrinsic-fallback --cfg force_intrinsic_fallback -O -Zm
 case $HOST_TARGET in
   x86_64-unknown-linux-gnu)
     # Only this branch runs in PR CI.
-    # Fully test all main OSes, including a 32bit target.
-    python3 "$X_PY" test --stage 2 src/tools/miri src/tools/miri/cargo-miri --target x86_64-apple-darwin
+    # Fully test all main OSes, and all main architectures.
+    python3 "$X_PY" test --stage 2 src/tools/miri src/tools/miri/cargo-miri --target aarch64-apple-darwin
     python3 "$X_PY" test --stage 2 src/tools/miri src/tools/miri/cargo-miri --target i686-pc-windows-msvc
     # Only run "pass" tests for the remaining targets, which is quite a bit faster.
     python3 "$X_PY" test --stage 2 src/tools/miri --target x86_64-pc-windows-gnu --test-args pass
@@ -69,7 +69,7 @@ case $HOST_TARGET in
     #FIXME: Re-enable this once CI issues are fixed
     # See <https://github.com/rust-lang/rust/issues/127883>
     # For now, these tests are moved to `x86_64-msvc-ext2` in `src/ci/github-actions/jobs.yml`.
-    #python3 "$X_PY" test --stage 2 src/tools/miri --target aarch64-apple-darwin --test-args pass
+    #python3 "$X_PY" test --stage 2 src/tools/miri --target x86_64-apple-darwin --test-args pass
     ;;
   *)
     echo "FATAL: unexpected host $HOST_TARGET"
diff --git a/src/ci/github-actions/jobs.yml b/src/ci/github-actions/jobs.yml
index dc6a0e1ebad8..9eedbd451d86 100644
--- a/src/ci/github-actions/jobs.yml
+++ b/src/ci/github-actions/jobs.yml
@@ -530,11 +530,13 @@ auto:
   - name: x86_64-msvc-ext2
     env:
       SCRIPT: >
-        python x.py test --stage 2 src/tools/miri --target aarch64-apple-darwin --test-args pass &&
+        python x.py test --stage 2 src/tools/miri --target x86_64-apple-darwin --test-args pass &&
         python x.py test --stage 2 src/tools/miri --target x86_64-pc-windows-gnu --test-args pass &&
         python x.py miri --stage 2 library/core --test-args notest &&
         python x.py miri --stage 2 library/alloc --test-args notest &&
         python x.py miri --stage 2 library/std --test-args notest
+      # The last 3 lines smoke-test `x.py miri`. This doesn't run any actual tests (that would take
+      # too long), but it ensures that the crates build properly when tested with Miri.
       RUST_CONFIGURE_ARGS: --build=x86_64-pc-windows-msvc --enable-lld
     <<: *job-windows
 
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index 0fbffc7808de..7e8e087c3a20 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -1749,7 +1749,7 @@ fn maybe_expand_private_type_alias<'tcx>(
     } else {
         return None;
     };
-    let hir::ItemKind::TyAlias(_, ty, generics) = alias else { return None };
+    let hir::ItemKind::TyAlias(_, generics, ty) = alias else { return None };
 
     let final_seg = &path.segments.last().expect("segments were empty");
     let mut args = DefIdMap::default();
@@ -2803,21 +2803,21 @@ fn clean_maybe_renamed_item<'tcx>(
         let mut name = get_name(cx, item, renamed).unwrap();
 
         let kind = match item.kind {
-            ItemKind::Static(_, ty, mutability, body_id) => StaticItem(Static {
+            ItemKind::Static(mutability, _, ty, body_id) => StaticItem(Static {
                 type_: Box::new(clean_ty(ty, cx)),
                 mutability,
                 expr: Some(body_id),
             }),
-            ItemKind::Const(_, ty, generics, body_id) => ConstantItem(Box::new(Constant {
+            ItemKind::Const(_, generics, ty, body_id) => ConstantItem(Box::new(Constant {
                 generics: clean_generics(generics, cx),
                 type_: clean_ty(ty, cx),
                 kind: ConstantKind::Local { body: body_id, def_id },
             })),
-            ItemKind::TyAlias(_, hir_ty, generics) => {
+            ItemKind::TyAlias(_, generics, ty) => {
                 *cx.current_type_aliases.entry(def_id).or_insert(0) += 1;
-                let rustdoc_ty = clean_ty(hir_ty, cx);
+                let rustdoc_ty = clean_ty(ty, cx);
                 let type_ =
-                    clean_middle_ty(ty::Binder::dummy(lower_ty(cx.tcx, hir_ty)), cx, None, None);
+                    clean_middle_ty(ty::Binder::dummy(lower_ty(cx.tcx, ty)), cx, None, None);
                 let generics = clean_generics(generics, cx);
                 if let Some(count) = cx.current_type_aliases.get_mut(&def_id) {
                     *count -= 1;
@@ -2846,7 +2846,7 @@ fn clean_maybe_renamed_item<'tcx>(
                 ));
                 return ret;
             }
-            ItemKind::Enum(_, def, generics) => EnumItem(Enum {
+            ItemKind::Enum(_, generics, def) => EnumItem(Enum {
                 variants: def.variants.iter().map(|v| clean_variant(v, cx)).collect(),
                 generics: clean_generics(generics, cx),
             }),
@@ -2854,11 +2854,11 @@ fn clean_maybe_renamed_item<'tcx>(
                 generics: clean_generics(generics, cx),
                 bounds: bounds.iter().filter_map(|x| clean_generic_bound(x, cx)).collect(),
             }),
-            ItemKind::Union(_, variant_data, generics) => UnionItem(Union {
+            ItemKind::Union(_, generics, variant_data) => UnionItem(Union {
                 generics: clean_generics(generics, cx),
                 fields: variant_data.fields().iter().map(|x| clean_field(x, cx)).collect(),
             }),
-            ItemKind::Struct(_, variant_data, generics) => StructItem(Struct {
+            ItemKind::Struct(_, generics, variant_data) => StructItem(Struct {
                 ctor_kind: variant_data.ctor_kind(),
                 generics: clean_generics(generics, cx),
                 fields: variant_data.fields().iter().map(|x| clean_field(x, cx)).collect(),
diff --git a/src/librustdoc/passes/calculate_doc_coverage.rs b/src/librustdoc/passes/calculate_doc_coverage.rs
index c9f0baaaa4c1..66d8b667a4ca 100644
--- a/src/librustdoc/passes/calculate_doc_coverage.rs
+++ b/src/librustdoc/passes/calculate_doc_coverage.rs
@@ -241,7 +241,7 @@ impl DocVisitor<'_> for CoverageCalculator<'_, '_> {
                                 data: hir::VariantData::Tuple(_, _, _),
                                 ..
                             }) | hir::Node::Item(hir::Item {
-                                kind: hir::ItemKind::Struct(_, hir::VariantData::Tuple(_, _, _), _),
+                                kind: hir::ItemKind::Struct(_, _, hir::VariantData::Tuple(_, _, _)),
                                 ..
                             })
                         )
diff --git a/src/tools/clippy/clippy_lints/src/arbitrary_source_item_ordering.rs b/src/tools/clippy/clippy_lints/src/arbitrary_source_item_ordering.rs
index 5c1c85d39184..59a0c7c88684 100644
--- a/src/tools/clippy/clippy_lints/src/arbitrary_source_item_ordering.rs
+++ b/src/tools/clippy/clippy_lints/src/arbitrary_source_item_ordering.rs
@@ -272,7 +272,7 @@ impl<'tcx> LateLintPass<'tcx> for ArbitrarySourceItemOrdering {
             return;
         }
         match &item.kind {
-            ItemKind::Enum(_, enum_def, _generics) if self.enable_ordering_for_enum => {
+            ItemKind::Enum(_, _generics, enum_def) if self.enable_ordering_for_enum => {
                 let mut cur_v: Option<&Variant<'_>> = None;
                 for variant in enum_def.variants {
                     if variant.span.in_external_macro(cx.sess().source_map()) {
@@ -288,7 +288,7 @@ impl<'tcx> LateLintPass<'tcx> for ArbitrarySourceItemOrdering {
                     cur_v = Some(variant);
                 }
             },
-            ItemKind::Struct(_, VariantData::Struct { fields, .. }, _generics) if self.enable_ordering_for_struct => {
+            ItemKind::Struct(_, _generics, VariantData::Struct { fields, .. }) if self.enable_ordering_for_struct => {
                 let mut cur_f: Option<&FieldDef<'_>> = None;
                 for field in *fields {
                     if field.span.in_external_macro(cx.sess().source_map()) {
diff --git a/src/tools/clippy/clippy_lints/src/empty_with_brackets.rs b/src/tools/clippy/clippy_lints/src/empty_with_brackets.rs
index 8c12364883c7..4414aebbf9a3 100644
--- a/src/tools/clippy/clippy_lints/src/empty_with_brackets.rs
+++ b/src/tools/clippy/clippy_lints/src/empty_with_brackets.rs
@@ -92,7 +92,7 @@ impl_lint_pass!(EmptyWithBrackets => [EMPTY_STRUCTS_WITH_BRACKETS, EMPTY_ENUM_VA
 
 impl LateLintPass<'_> for EmptyWithBrackets {
     fn check_item(&mut self, cx: &LateContext<'_>, item: &Item<'_>) {
-        if let ItemKind::Struct(ident, var_data, _) = &item.kind
+        if let ItemKind::Struct(ident, _, var_data) = &item.kind
             && !item.span.from_expansion()
             && has_brackets(var_data)
             && let span_after_ident = item.span.with_lo(ident.span.hi())
diff --git a/src/tools/clippy/clippy_lints/src/enum_clike.rs b/src/tools/clippy/clippy_lints/src/enum_clike.rs
index ec81294624ef..098571a53512 100644
--- a/src/tools/clippy/clippy_lints/src/enum_clike.rs
+++ b/src/tools/clippy/clippy_lints/src/enum_clike.rs
@@ -38,7 +38,7 @@ impl<'tcx> LateLintPass<'tcx> for UnportableVariant {
         if cx.tcx.data_layout.pointer_size.bits() != 64 {
             return;
         }
-        if let ItemKind::Enum(_, def, _) = &item.kind {
+        if let ItemKind::Enum(_, _, def) = &item.kind {
             for var in def.variants {
                 if let Some(anon_const) = &var.disr_expr {
                     let def_id = cx.tcx.hir_body_owner_def_id(anon_const.body);
diff --git a/src/tools/clippy/clippy_lints/src/excessive_bools.rs b/src/tools/clippy/clippy_lints/src/excessive_bools.rs
index 38d115b878c7..686dc5c3c4fc 100644
--- a/src/tools/clippy/clippy_lints/src/excessive_bools.rs
+++ b/src/tools/clippy/clippy_lints/src/excessive_bools.rs
@@ -127,7 +127,7 @@ fn check_fn_decl(cx: &LateContext<'_>, decl: &FnDecl<'_>, sp: Span, max: u64) {
 
 impl<'tcx> LateLintPass<'tcx> for ExcessiveBools {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'tcx>) {
-        if let ItemKind::Struct(_, variant_data, _) = &item.kind
+        if let ItemKind::Struct(_, _, variant_data) = &item.kind
             && variant_data.fields().len() as u64 > self.max_struct_bools
             && has_n_bools(
                 variant_data.fields().iter().map(|field| field.ty),
diff --git a/src/tools/clippy/clippy_lints/src/exhaustive_items.rs b/src/tools/clippy/clippy_lints/src/exhaustive_items.rs
index 5a74e97c97c5..1fb0e4d24d06 100644
--- a/src/tools/clippy/clippy_lints/src/exhaustive_items.rs
+++ b/src/tools/clippy/clippy_lints/src/exhaustive_items.rs
@@ -76,7 +76,7 @@ impl LateLintPass<'_> for ExhaustiveItems {
                 "exported enums should not be exhaustive",
                 [].as_slice(),
             ),
-            ItemKind::Struct(_, v, ..) => (
+            ItemKind::Struct(_, _, v) => (
                 EXHAUSTIVE_STRUCTS,
                 "exported structs should not be exhaustive",
                 v.fields(),
diff --git a/src/tools/clippy/clippy_lints/src/functions/result.rs b/src/tools/clippy/clippy_lints/src/functions/result.rs
index 00ce4cfcc526..bb98ae826111 100644
--- a/src/tools/clippy/clippy_lints/src/functions/result.rs
+++ b/src/tools/clippy/clippy_lints/src/functions/result.rs
@@ -103,7 +103,7 @@ fn check_result_large_err<'tcx>(cx: &LateContext<'tcx>, err_ty: Ty<'tcx>, hir_ty
             .did()
             .as_local()
         && let hir::Node::Item(item) = cx.tcx.hir_node_by_def_id(local_def_id)
-        && let hir::ItemKind::Enum(_, ref def, _) = item.kind
+        && let hir::ItemKind::Enum(_, _, ref def) = item.kind
     {
         let variants_size = AdtVariantInfo::new(cx, *adt, subst);
         if let Some((first_variant, variants)) = variants_size.split_first()
diff --git a/src/tools/clippy/clippy_lints/src/item_name_repetitions.rs b/src/tools/clippy/clippy_lints/src/item_name_repetitions.rs
index 3d4dcd020702..9c91cf680851 100644
--- a/src/tools/clippy/clippy_lints/src/item_name_repetitions.rs
+++ b/src/tools/clippy/clippy_lints/src/item_name_repetitions.rs
@@ -535,10 +535,10 @@ impl LateLintPass<'_> for ItemNameRepetitions {
 
         if span_is_local(item.span) {
             match item.kind {
-                ItemKind::Enum(_, def, _) => {
+                ItemKind::Enum(_, _, def) => {
                     self.check_variants(cx, item, &def);
                 },
-                ItemKind::Struct(_, VariantData::Struct { fields, .. }, _) => {
+                ItemKind::Struct(_, _, VariantData::Struct { fields, .. }) => {
                     self.check_fields(cx, item, fields);
                 },
                 _ => (),
diff --git a/src/tools/clippy/clippy_lints/src/large_const_arrays.rs b/src/tools/clippy/clippy_lints/src/large_const_arrays.rs
index 394005e99129..cee8ca1261e5 100644
--- a/src/tools/clippy/clippy_lints/src/large_const_arrays.rs
+++ b/src/tools/clippy/clippy_lints/src/large_const_arrays.rs
@@ -48,7 +48,7 @@ impl_lint_pass!(LargeConstArrays => [LARGE_CONST_ARRAYS]);
 
 impl<'tcx> LateLintPass<'tcx> for LargeConstArrays {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
-        if let ItemKind::Const(ident, _, generics, _) = &item.kind
+        if let ItemKind::Const(ident, generics, _, _) = &item.kind
             // Since static items may not have generics, skip generic const items.
             // FIXME(generic_const_items): I don't think checking `generics.hwcp` suffices as it
             // doesn't account for empty where-clauses that only consist of keyword `where` IINM.
diff --git a/src/tools/clippy/clippy_lints/src/large_enum_variant.rs b/src/tools/clippy/clippy_lints/src/large_enum_variant.rs
index d08efa0ec9cc..e85d779b4880 100644
--- a/src/tools/clippy/clippy_lints/src/large_enum_variant.rs
+++ b/src/tools/clippy/clippy_lints/src/large_enum_variant.rs
@@ -73,7 +73,7 @@ impl_lint_pass!(LargeEnumVariant => [LARGE_ENUM_VARIANT]);
 
 impl<'tcx> LateLintPass<'tcx> for LargeEnumVariant {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &Item<'tcx>) {
-        if let ItemKind::Enum(ident, ref def, _) = item.kind
+        if let ItemKind::Enum(ident, _, ref def) = item.kind
             && let ty = cx.tcx.type_of(item.owner_id).instantiate_identity()
             && let ty::Adt(adt, subst) = ty.kind()
             && adt.variants().len() > 1
diff --git a/src/tools/clippy/clippy_lints/src/manual_non_exhaustive.rs b/src/tools/clippy/clippy_lints/src/manual_non_exhaustive.rs
index 067b92cd46ee..3562b1ff5cce 100644
--- a/src/tools/clippy/clippy_lints/src/manual_non_exhaustive.rs
+++ b/src/tools/clippy/clippy_lints/src/manual_non_exhaustive.rs
@@ -87,7 +87,7 @@ impl<'tcx> LateLintPass<'tcx> for ManualNonExhaustive {
         }
 
         match item.kind {
-            ItemKind::Enum(_, def, _) if def.variants.len() > 1 => {
+            ItemKind::Enum(_, _, def) if def.variants.len() > 1 => {
                 let iter = def.variants.iter().filter_map(|v| {
                     (matches!(v.data, VariantData::Unit(_, _)) && is_doc_hidden(cx.tcx.hir_attrs(v.hir_id)))
                         .then_some((v.def_id, v.span))
@@ -98,7 +98,7 @@ impl<'tcx> LateLintPass<'tcx> for ManualNonExhaustive {
                     self.potential_enums.push((item.owner_id.def_id, id, item.span, span));
                 }
             },
-            ItemKind::Struct(_, variant_data, _) => {
+            ItemKind::Struct(_, _, variant_data) => {
                 let fields = variant_data.fields();
                 let private_fields = fields
                     .iter()
diff --git a/src/tools/clippy/clippy_lints/src/missing_fields_in_debug.rs b/src/tools/clippy/clippy_lints/src/missing_fields_in_debug.rs
index be7dd74fd62b..d4d33029dbdb 100644
--- a/src/tools/clippy/clippy_lints/src/missing_fields_in_debug.rs
+++ b/src/tools/clippy/clippy_lints/src/missing_fields_in_debug.rs
@@ -225,7 +225,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingFieldsInDebug {
             && let typeck_results = cx.tcx.typeck_body(*body_id)
             && should_lint(cx, typeck_results, block)
             // we intentionally only lint structs, see lint description
-            && let ItemKind::Struct(_, data, _) = &self_item.kind
+            && let ItemKind::Struct(_, _, data) = &self_item.kind
         {
             check_struct(cx, typeck_results, block, self_ty, item, data);
         }
diff --git a/src/tools/clippy/clippy_lints/src/non_std_lazy_statics.rs b/src/tools/clippy/clippy_lints/src/non_std_lazy_statics.rs
index f66b9519317b..abee3c44c5a3 100644
--- a/src/tools/clippy/clippy_lints/src/non_std_lazy_statics.rs
+++ b/src/tools/clippy/clippy_lints/src/non_std_lazy_statics.rs
@@ -187,7 +187,7 @@ struct LazyInfo {
 impl LazyInfo {
     fn from_item(cx: &LateContext<'_>, item: &Item<'_>) -> Option<Self> {
         // Check if item is a `once_cell:sync::Lazy` static.
-        if let ItemKind::Static(_, ty, _, body_id) = item.kind
+        if let ItemKind::Static(_, _, ty, body_id) = item.kind
             && let Some(path_def_id) = path_def_id(cx, ty)
             && let hir::TyKind::Path(hir::QPath::Resolved(_, path)) = ty.kind
             && paths::ONCE_CELL_SYNC_LAZY.matches(cx, path_def_id)
diff --git a/src/tools/clippy/clippy_lints/src/pub_underscore_fields.rs b/src/tools/clippy/clippy_lints/src/pub_underscore_fields.rs
index e4a9bf7a8481..66c59cb70d36 100644
--- a/src/tools/clippy/clippy_lints/src/pub_underscore_fields.rs
+++ b/src/tools/clippy/clippy_lints/src/pub_underscore_fields.rs
@@ -58,7 +58,7 @@ impl PubUnderscoreFields {
 impl<'tcx> LateLintPass<'tcx> for PubUnderscoreFields {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
         // This lint only pertains to structs.
-        let ItemKind::Struct(_, variant_data, _) = &item.kind else {
+        let ItemKind::Struct(_, _, variant_data) = &item.kind else {
             return;
         };
 
diff --git a/src/tools/clippy/clippy_lints/src/trailing_empty_array.rs b/src/tools/clippy/clippy_lints/src/trailing_empty_array.rs
index 20bf3a0bff1c..75a82770af04 100644
--- a/src/tools/clippy/clippy_lints/src/trailing_empty_array.rs
+++ b/src/tools/clippy/clippy_lints/src/trailing_empty_array.rs
@@ -57,7 +57,7 @@ impl<'tcx> LateLintPass<'tcx> for TrailingEmptyArray {
 }
 
 fn is_struct_with_trailing_zero_sized_array<'tcx>(cx: &LateContext<'tcx>, item: &Item<'tcx>) -> bool {
-    if let ItemKind::Struct(_, data, _) = &item.kind
+    if let ItemKind::Struct(_, _, data) = &item.kind
         && let Some(last_field) = data.fields().last()
         && let field_ty = cx.tcx.normalize_erasing_regions(
             cx.typing_env(),
diff --git a/src/tools/clippy/clippy_lints/src/types/mod.rs b/src/tools/clippy/clippy_lints/src/types/mod.rs
index c1c7cc516565..515be5adeed0 100644
--- a/src/tools/clippy/clippy_lints/src/types/mod.rs
+++ b/src/tools/clippy/clippy_lints/src/types/mod.rs
@@ -447,7 +447,7 @@ impl<'tcx> LateLintPass<'tcx> for Types {
         let is_exported = cx.effective_visibilities.is_exported(item.owner_id.def_id);
 
         match item.kind {
-            ItemKind::Static(_, ty, _, _) | ItemKind::Const(_, ty, _, _) => self.check_ty(
+            ItemKind::Static(_, _, ty, _) | ItemKind::Const(_, _, ty, _) => self.check_ty(
                 cx,
                 ty,
                 CheckTyContext {
diff --git a/src/tools/clippy/clippy_lints/src/upper_case_acronyms.rs b/src/tools/clippy/clippy_lints/src/upper_case_acronyms.rs
index 8922478e7183..02281b9e9223 100644
--- a/src/tools/clippy/clippy_lints/src/upper_case_acronyms.rs
+++ b/src/tools/clippy/clippy_lints/src/upper_case_acronyms.rs
@@ -134,7 +134,7 @@ impl LateLintPass<'_> for UpperCaseAcronyms {
             ItemKind::TyAlias(ident, ..) | ItemKind::Struct(ident, ..) | ItemKind::Trait(_, _, ident, ..) => {
                 check_ident(cx, &ident, it.hir_id(), self.upper_case_acronyms_aggressive);
             },
-            ItemKind::Enum(ident, ref enumdef, _) => {
+            ItemKind::Enum(ident, _, ref enumdef) => {
                 check_ident(cx, &ident, it.hir_id(), self.upper_case_acronyms_aggressive);
                 // check enum variants separately because again we only want to lint on private enums and
                 // the fn check_variant does not know about the vis of the enum of its variants
diff --git a/src/tools/clippy/clippy_utils/src/check_proc_macro.rs b/src/tools/clippy/clippy_utils/src/check_proc_macro.rs
index 004c840c3310..407e92d88fb0 100644
--- a/src/tools/clippy/clippy_utils/src/check_proc_macro.rs
+++ b/src/tools/clippy/clippy_utils/src/check_proc_macro.rs
@@ -249,7 +249,7 @@ fn item_search_pat(item: &Item<'_>) -> (Pat, Pat) {
         ItemKind::ForeignMod { .. } => (Pat::Str("extern"), Pat::Str("}")),
         ItemKind::TyAlias(..) => (Pat::Str("type"), Pat::Str(";")),
         ItemKind::Enum(..) => (Pat::Str("enum"), Pat::Str("}")),
-        ItemKind::Struct(_, VariantData::Struct { .. }, _) => (Pat::Str("struct"), Pat::Str("}")),
+        ItemKind::Struct(_, _, VariantData::Struct { .. }) => (Pat::Str("struct"), Pat::Str("}")),
         ItemKind::Struct(..) => (Pat::Str("struct"), Pat::Str(";")),
         ItemKind::Union(..) => (Pat::Str("union"), Pat::Str("}")),
         ItemKind::Trait(_, Safety::Unsafe, ..)
diff --git a/src/tools/clippy/clippy_utils/src/lib.rs b/src/tools/clippy/clippy_utils/src/lib.rs
index 8716ee48c88f..2020f3d6b5bd 100644
--- a/src/tools/clippy/clippy_utils/src/lib.rs
+++ b/src/tools/clippy/clippy_utils/src/lib.rs
@@ -2362,7 +2362,7 @@ fn with_test_item_names(tcx: TyCtxt<'_>, module: LocalModDefId, f: impl FnOnce(&
             for id in tcx.hir_module_free_items(module) {
                 if matches!(tcx.def_kind(id.owner_id), DefKind::Const)
                     && let item = tcx.hir_item(id)
-                    && let ItemKind::Const(ident, ty, _generics, _body) = item.kind
+                    && let ItemKind::Const(ident, _generics, ty, _body) = item.kind
                     && let TyKind::Path(QPath::Resolved(_, path)) = ty.kind
                         // We could also check for the type name `test::TestDescAndFn`
                         && let Res::Def(DefKind::Struct, _) = path.res
diff --git a/src/tools/clippy/tests/ui/map_flatten.rs b/src/tools/clippy/tests/ui/map_flatten.rs
index d7e9c9d9900d..0970da8039a4 100644
--- a/src/tools/clippy/tests/ui/map_flatten.rs
+++ b/src/tools/clippy/tests/ui/map_flatten.rs
@@ -1,5 +1,5 @@
 #![warn(clippy::map_flatten)]
-#![feature(result_flattening)]
+
 //@no-rustfix
 // issue #8506, multi-line
 #[rustfmt::skip]
diff --git a/src/tools/clippy/tests/ui/map_flatten_fixable.fixed b/src/tools/clippy/tests/ui/map_flatten_fixable.fixed
index f8379ed23c5b..6d8a27d3018d 100644
--- a/src/tools/clippy/tests/ui/map_flatten_fixable.fixed
+++ b/src/tools/clippy/tests/ui/map_flatten_fixable.fixed
@@ -1,4 +1,3 @@
-#![feature(result_flattening)]
 #![allow(
     clippy::let_underscore_untyped,
     clippy::missing_docs_in_private_items,
diff --git a/src/tools/clippy/tests/ui/map_flatten_fixable.rs b/src/tools/clippy/tests/ui/map_flatten_fixable.rs
index 040a9ca85f64..845e3a79ae2b 100644
--- a/src/tools/clippy/tests/ui/map_flatten_fixable.rs
+++ b/src/tools/clippy/tests/ui/map_flatten_fixable.rs
@@ -1,4 +1,3 @@
-#![feature(result_flattening)]
 #![allow(
     clippy::let_underscore_untyped,
     clippy::missing_docs_in_private_items,
diff --git a/src/tools/clippy/tests/ui/map_flatten_fixable.stderr b/src/tools/clippy/tests/ui/map_flatten_fixable.stderr
index fe68eb7e4ab4..05d4d9a6ad85 100644
--- a/src/tools/clippy/tests/ui/map_flatten_fixable.stderr
+++ b/src/tools/clippy/tests/ui/map_flatten_fixable.stderr
@@ -1,5 +1,5 @@
 error: called `map(..).flatten()` on `Iterator`
-  --> tests/ui/map_flatten_fixable.rs:17:47
+  --> tests/ui/map_flatten_fixable.rs:16:47
    |
 LL |     let _: Vec<_> = vec![5_i8; 6].into_iter().map(option_id).flatten().collect();
    |                                               ^^^^^^^^^^^^^^^^^^^^^^^^ help: try replacing `map` with `filter_map` and remove the `.flatten()`: `filter_map(option_id)`
@@ -8,43 +8,43 @@ LL |     let _: Vec<_> = vec![5_i8; 6].into_iter().map(option_id).flatten().coll
    = help: to override `-D warnings` add `#[allow(clippy::map_flatten)]`
 
 error: called `map(..).flatten()` on `Iterator`
-  --> tests/ui/map_flatten_fixable.rs:19:47
+  --> tests/ui/map_flatten_fixable.rs:18:47
    |
 LL |     let _: Vec<_> = vec![5_i8; 6].into_iter().map(option_id_ref).flatten().collect();
    |                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try replacing `map` with `filter_map` and remove the `.flatten()`: `filter_map(option_id_ref)`
 
 error: called `map(..).flatten()` on `Iterator`
-  --> tests/ui/map_flatten_fixable.rs:21:47
+  --> tests/ui/map_flatten_fixable.rs:20:47
    |
 LL |     let _: Vec<_> = vec![5_i8; 6].into_iter().map(option_id_closure).flatten().collect();
    |                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try replacing `map` with `filter_map` and remove the `.flatten()`: `filter_map(option_id_closure)`
 
 error: called `map(..).flatten()` on `Iterator`
-  --> tests/ui/map_flatten_fixable.rs:23:47
+  --> tests/ui/map_flatten_fixable.rs:22:47
    |
 LL |     let _: Vec<_> = vec![5_i8; 6].into_iter().map(|x| x.checked_add(1)).flatten().collect();
    |                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try replacing `map` with `filter_map` and remove the `.flatten()`: `filter_map(|x| x.checked_add(1))`
 
 error: called `map(..).flatten()` on `Iterator`
-  --> tests/ui/map_flatten_fixable.rs:27:47
+  --> tests/ui/map_flatten_fixable.rs:26:47
    |
 LL |     let _: Vec<_> = vec![5_i8; 6].into_iter().map(|x| 0..x).flatten().collect();
    |                                               ^^^^^^^^^^^^^^^^^^^^^^^ help: try replacing `map` with `flat_map` and remove the `.flatten()`: `flat_map(|x| 0..x)`
 
 error: called `map(..).flatten()` on `Option`
-  --> tests/ui/map_flatten_fixable.rs:31:40
+  --> tests/ui/map_flatten_fixable.rs:30:40
    |
 LL |     let _: Option<_> = (Some(Some(1))).map(|x| x).flatten();
    |                                        ^^^^^^^^^^^^^^^^^^^^ help: try replacing `map` with `and_then` and remove the `.flatten()`: `and_then(|x| x)`
 
 error: called `map(..).flatten()` on `Result`
-  --> tests/ui/map_flatten_fixable.rs:35:42
+  --> tests/ui/map_flatten_fixable.rs:34:42
    |
 LL |     let _: Result<_, &str> = (Ok(Ok(1))).map(|x| x).flatten();
    |                                          ^^^^^^^^^^^^^^^^^^^^ help: try replacing `map` with `and_then` and remove the `.flatten()`: `and_then(|x| x)`
 
 error: called `map(..).flatten()` on `Iterator`
-  --> tests/ui/map_flatten_fixable.rs:45:10
+  --> tests/ui/map_flatten_fixable.rs:44:10
    |
 LL |           .map(|n| match n {
    |  __________^
@@ -74,7 +74,7 @@ LL ~         });
    |
 
 error: called `map(..).flatten()` on `Option`
-  --> tests/ui/map_flatten_fixable.rs:66:10
+  --> tests/ui/map_flatten_fixable.rs:65:10
    |
 LL |           .map(|_| {
    |  __________^
diff --git a/src/tools/miri/src/intrinsics/mod.rs b/src/tools/miri/src/intrinsics/mod.rs
index 581005bc9a1e..a4882a201481 100644
--- a/src/tools/miri/src/intrinsics/mod.rs
+++ b/src/tools/miri/src/intrinsics/mod.rs
@@ -159,67 +159,6 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 this.write_scalar(Scalar::from_bool(branch), dest)?;
             }
 
-            "floorf16" | "ceilf16" | "truncf16" | "roundf16" | "round_ties_even_f16" => {
-                let [f] = check_intrinsic_arg_count(args)?;
-                let f = this.read_scalar(f)?.to_f16()?;
-                let mode = match intrinsic_name {
-                    "floorf16" => Round::TowardNegative,
-                    "ceilf16" => Round::TowardPositive,
-                    "truncf16" => Round::TowardZero,
-                    "roundf16" => Round::NearestTiesToAway,
-                    "round_ties_even_f16" => Round::NearestTiesToEven,
-                    _ => bug!(),
-                };
-                let res = f.round_to_integral(mode).value;
-                let res = this.adjust_nan(res, &[f]);
-                this.write_scalar(res, dest)?;
-            }
-            "floorf32" | "ceilf32" | "truncf32" | "roundf32" | "round_ties_even_f32" => {
-                let [f] = check_intrinsic_arg_count(args)?;
-                let f = this.read_scalar(f)?.to_f32()?;
-                let mode = match intrinsic_name {
-                    "floorf32" => Round::TowardNegative,
-                    "ceilf32" => Round::TowardPositive,
-                    "truncf32" => Round::TowardZero,
-                    "roundf32" => Round::NearestTiesToAway,
-                    "round_ties_even_f32" => Round::NearestTiesToEven,
-                    _ => bug!(),
-                };
-                let res = f.round_to_integral(mode).value;
-                let res = this.adjust_nan(res, &[f]);
-                this.write_scalar(res, dest)?;
-            }
-            "floorf64" | "ceilf64" | "truncf64" | "roundf64" | "round_ties_even_f64" => {
-                let [f] = check_intrinsic_arg_count(args)?;
-                let f = this.read_scalar(f)?.to_f64()?;
-                let mode = match intrinsic_name {
-                    "floorf64" => Round::TowardNegative,
-                    "ceilf64" => Round::TowardPositive,
-                    "truncf64" => Round::TowardZero,
-                    "roundf64" => Round::NearestTiesToAway,
-                    "round_ties_even_f64" => Round::NearestTiesToEven,
-                    _ => bug!(),
-                };
-                let res = f.round_to_integral(mode).value;
-                let res = this.adjust_nan(res, &[f]);
-                this.write_scalar(res, dest)?;
-            }
-            "floorf128" | "ceilf128" | "truncf128" | "roundf128" | "round_ties_even_f128" => {
-                let [f] = check_intrinsic_arg_count(args)?;
-                let f = this.read_scalar(f)?.to_f128()?;
-                let mode = match intrinsic_name {
-                    "floorf128" => Round::TowardNegative,
-                    "ceilf128" => Round::TowardPositive,
-                    "truncf128" => Round::TowardZero,
-                    "roundf128" => Round::NearestTiesToAway,
-                    "round_ties_even_f128" => Round::NearestTiesToEven,
-                    _ => bug!(),
-                };
-                let res = f.round_to_integral(mode).value;
-                let res = this.adjust_nan(res, &[f]);
-                this.write_scalar(res, dest)?;
-            }
-
             "sqrtf32" => {
                 let [f] = check_intrinsic_arg_count(args)?;
                 let f = this.read_scalar(f)?.to_f32()?;
diff --git a/tests/mir-opt/dataflow.main.maybe_init.borrowck.dot b/tests/mir-opt/dataflow.main.maybe_init.borrowck.dot
deleted file mode 100644
index 7c7d8921fb36..000000000000
--- a/tests/mir-opt/dataflow.main.maybe_init.borrowck.dot
+++ /dev/null
@@ -1,6 +0,0 @@
-digraph graph_for_def_id_0_3 {
-    graph[fontname="Courier, monospace"];
-    node[fontname="Courier, monospace"];
-    edge[fontname="Courier, monospace"];
-    bb_0[label=<<table border="1" cellborder="1" cellspacing="0" cellpadding="3" sides="rb"><tr><td colspan="3" sides="tl">bb0</td></tr><tr><td colspan="2" bgcolor="#a0a0a0" sides="tl">MIR</td><td bgcolor="#a0a0a0" sides="tl">STATE</td></tr><tr><td valign="bottom" sides="tl"  align="right"></td><td valign="bottom" sides="tl"  align="left">(on start)</td><td colspan="1" valign="bottom" sides="tl"  align="left">{}</td></tr><tr><td valign="top" sides="tl" bgcolor="#f0f0f0" align="right">0</td><td valign="top" sides="tl" bgcolor="#f0f0f0" align="left">_0 = const ()</td><td valign="top" sides="tl" bgcolor="#f0f0f0" align="left"><font color="darkgreen">+_0</font></td></tr><tr><td valign="top" sides="tl"  align="right">T</td><td valign="top" sides="tl"  align="left">return</td><td valign="top" sides="tl"  align="left"></td></tr><tr><td valign="bottom" sides="tl" bgcolor="#f0f0f0" align="right"></td><td valign="bottom" sides="tl" bgcolor="#f0f0f0" align="left">(on end)</td><td colspan="1" valign="bottom" sides="tl" bgcolor="#f0f0f0" align="left">{_0}</td></tr></table>>][shape="none"];
-}
diff --git a/tests/mir-opt/dataflow.main.maybe_uninit.borrowck.dot b/tests/mir-opt/dataflow.main.maybe_uninit.borrowck.dot
new file mode 100644
index 000000000000..258404b8da78
--- /dev/null
+++ b/tests/mir-opt/dataflow.main.maybe_uninit.borrowck.dot
@@ -0,0 +1,6 @@
+digraph graph_for_def_id_0_3 {
+    graph[fontname="Courier, monospace"];
+    node[fontname="Courier, monospace"];
+    edge[fontname="Courier, monospace"];
+    bb_0[label=<<table border="1" cellborder="1" cellspacing="0" cellpadding="3" sides="rb"><tr><td colspan="3" sides="tl">bb0</td></tr><tr><td colspan="2" bgcolor="#a0a0a0" sides="tl">MIR</td><td bgcolor="#a0a0a0" sides="tl">STATE</td></tr><tr><td valign="bottom" sides="tl"  align="right"></td><td valign="bottom" sides="tl"  align="left">(on start)</td><td colspan="1" valign="bottom" sides="tl"  align="left">{_0}</td></tr><tr><td valign="top" sides="tl" bgcolor="#f0f0f0" align="right">0</td><td valign="top" sides="tl" bgcolor="#f0f0f0" align="left">_0 = const ()</td><td valign="top" sides="tl" bgcolor="#f0f0f0" align="left"><font color="red">-_0</font></td></tr><tr><td valign="top" sides="tl"  align="right">T</td><td valign="top" sides="tl"  align="left">return</td><td valign="top" sides="tl"  align="left"></td></tr><tr><td valign="bottom" sides="tl" bgcolor="#f0f0f0" align="right"></td><td valign="bottom" sides="tl" bgcolor="#f0f0f0" align="left">(on end)</td><td colspan="1" valign="bottom" sides="tl" bgcolor="#f0f0f0" align="left">{}</td></tr></table>>][shape="none"];
+}
diff --git a/tests/mir-opt/dataflow.rs b/tests/mir-opt/dataflow.rs
index 3a28f5d47b9a..5ed3da4c531a 100644
--- a/tests/mir-opt/dataflow.rs
+++ b/tests/mir-opt/dataflow.rs
@@ -2,5 +2,5 @@
 // Test graphviz dataflow output
 //@ compile-flags: -Z dump-mir=main -Z dump-mir-dataflow
 
-// EMIT_MIR dataflow.main.maybe_init.borrowck.dot
+// EMIT_MIR dataflow.main.maybe_uninit.borrowck.dot
 fn main() {}
diff --git a/tests/mir-opt/lower_intrinsics.rs b/tests/mir-opt/lower_intrinsics.rs
index 4e000b05a4b4..1e4f20241947 100644
--- a/tests/mir-opt/lower_intrinsics.rs
+++ b/tests/mir-opt/lower_intrinsics.rs
@@ -263,3 +263,24 @@ pub fn get_metadata(a: *const i32, b: *const [u8], c: *const dyn std::fmt::Debug
     let _usize = ptr_metadata(b);
     let _vtable = ptr_metadata(c);
 }
+
+// EMIT_MIR lower_intrinsics.slice_get.LowerIntrinsics.diff
+pub unsafe fn slice_get<'a, 'b>(
+    r: &'a [i8],
+    rm: &'b mut [i16],
+    p: *const [i32],
+    pm: *mut [i64],
+    i: usize,
+) -> (&'a i8, &'b mut i16, *const i32, *mut i64) {
+    use std::intrinsics::slice_get_unchecked;
+    // CHECK: = &(*_{{[0-9]+}})[_{{[0-9]+}}]
+    // CHECK: = &mut (*_{{[0-9]+}})[_{{[0-9]+}}]
+    // CHECK: = &raw const (*_{{[0-9]+}})[_{{[0-9]+}}]
+    // CHECK: = &raw mut (*_{{[0-9]+}})[_{{[0-9]+}}]
+    (
+        slice_get_unchecked(r, i),
+        slice_get_unchecked(rm, i),
+        slice_get_unchecked(p, i),
+        slice_get_unchecked(pm, i),
+    )
+}
diff --git a/tests/mir-opt/lower_intrinsics.slice_get.LowerIntrinsics.panic-abort.diff b/tests/mir-opt/lower_intrinsics.slice_get.LowerIntrinsics.panic-abort.diff
new file mode 100644
index 000000000000..d18bdc431683
--- /dev/null
+++ b/tests/mir-opt/lower_intrinsics.slice_get.LowerIntrinsics.panic-abort.diff
@@ -0,0 +1,85 @@
+- // MIR for `slice_get` before LowerIntrinsics
++ // MIR for `slice_get` after LowerIntrinsics
+  
+  fn slice_get(_1: &[i8], _2: &mut [i16], _3: *const [i32], _4: *mut [i64], _5: usize) -> (&i8, &mut i16, *const i32, *mut i64) {
+      debug r => _1;
+      debug rm => _2;
+      debug p => _3;
+      debug pm => _4;
+      debug i => _5;
+      let mut _0: (&i8, &mut i16, *const i32, *mut i64);
+      let mut _6: &i8;
+      let mut _7: &[i8];
+      let mut _8: usize;
+      let mut _9: &mut i16;
+      let mut _10: &mut [i16];
+      let mut _11: usize;
+      let mut _12: *const i32;
+      let mut _13: *const [i32];
+      let mut _14: usize;
+      let mut _15: *mut i64;
+      let mut _16: *mut [i64];
+      let mut _17: usize;
+  
+      bb0: {
+          StorageLive(_6);
+          StorageLive(_7);
+          _7 = copy _1;
+          StorageLive(_8);
+          _8 = copy _5;
+-         _6 = slice_get_unchecked::<&i8, &[i8], i8>(move _7, move _8) -> [return: bb1, unwind unreachable];
++         _6 = &(*_7)[_8];
++         goto -> bb1;
+      }
+  
+      bb1: {
+          StorageDead(_8);
+          StorageDead(_7);
+          StorageLive(_9);
+          StorageLive(_10);
+          _10 = move _2;
+          StorageLive(_11);
+          _11 = copy _5;
+-         _9 = slice_get_unchecked::<&mut i16, &mut [i16], i16>(move _10, move _11) -> [return: bb2, unwind unreachable];
++         _9 = &mut (*_10)[_11];
++         goto -> bb2;
+      }
+  
+      bb2: {
+          StorageDead(_11);
+          StorageDead(_10);
+          StorageLive(_12);
+          StorageLive(_13);
+          _13 = copy _3;
+          StorageLive(_14);
+          _14 = copy _5;
+-         _12 = slice_get_unchecked::<*const i32, *const [i32], i32>(move _13, move _14) -> [return: bb3, unwind unreachable];
++         _12 = &raw const (*_13)[_14];
++         goto -> bb3;
+      }
+  
+      bb3: {
+          StorageDead(_14);
+          StorageDead(_13);
+          StorageLive(_15);
+          StorageLive(_16);
+          _16 = copy _4;
+          StorageLive(_17);
+          _17 = copy _5;
+-         _15 = slice_get_unchecked::<*mut i64, *mut [i64], i64>(move _16, move _17) -> [return: bb4, unwind unreachable];
++         _15 = &raw mut (*_16)[_17];
++         goto -> bb4;
+      }
+  
+      bb4: {
+          StorageDead(_17);
+          StorageDead(_16);
+          _0 = (move _6, move _9, move _12, move _15);
+          StorageDead(_15);
+          StorageDead(_12);
+          StorageDead(_9);
+          StorageDead(_6);
+          return;
+      }
+  }
+  
diff --git a/tests/mir-opt/lower_intrinsics.slice_get.LowerIntrinsics.panic-unwind.diff b/tests/mir-opt/lower_intrinsics.slice_get.LowerIntrinsics.panic-unwind.diff
new file mode 100644
index 000000000000..d18bdc431683
--- /dev/null
+++ b/tests/mir-opt/lower_intrinsics.slice_get.LowerIntrinsics.panic-unwind.diff
@@ -0,0 +1,85 @@
+- // MIR for `slice_get` before LowerIntrinsics
++ // MIR for `slice_get` after LowerIntrinsics
+  
+  fn slice_get(_1: &[i8], _2: &mut [i16], _3: *const [i32], _4: *mut [i64], _5: usize) -> (&i8, &mut i16, *const i32, *mut i64) {
+      debug r => _1;
+      debug rm => _2;
+      debug p => _3;
+      debug pm => _4;
+      debug i => _5;
+      let mut _0: (&i8, &mut i16, *const i32, *mut i64);
+      let mut _6: &i8;
+      let mut _7: &[i8];
+      let mut _8: usize;
+      let mut _9: &mut i16;
+      let mut _10: &mut [i16];
+      let mut _11: usize;
+      let mut _12: *const i32;
+      let mut _13: *const [i32];
+      let mut _14: usize;
+      let mut _15: *mut i64;
+      let mut _16: *mut [i64];
+      let mut _17: usize;
+  
+      bb0: {
+          StorageLive(_6);
+          StorageLive(_7);
+          _7 = copy _1;
+          StorageLive(_8);
+          _8 = copy _5;
+-         _6 = slice_get_unchecked::<&i8, &[i8], i8>(move _7, move _8) -> [return: bb1, unwind unreachable];
++         _6 = &(*_7)[_8];
++         goto -> bb1;
+      }
+  
+      bb1: {
+          StorageDead(_8);
+          StorageDead(_7);
+          StorageLive(_9);
+          StorageLive(_10);
+          _10 = move _2;
+          StorageLive(_11);
+          _11 = copy _5;
+-         _9 = slice_get_unchecked::<&mut i16, &mut [i16], i16>(move _10, move _11) -> [return: bb2, unwind unreachable];
++         _9 = &mut (*_10)[_11];
++         goto -> bb2;
+      }
+  
+      bb2: {
+          StorageDead(_11);
+          StorageDead(_10);
+          StorageLive(_12);
+          StorageLive(_13);
+          _13 = copy _3;
+          StorageLive(_14);
+          _14 = copy _5;
+-         _12 = slice_get_unchecked::<*const i32, *const [i32], i32>(move _13, move _14) -> [return: bb3, unwind unreachable];
++         _12 = &raw const (*_13)[_14];
++         goto -> bb3;
+      }
+  
+      bb3: {
+          StorageDead(_14);
+          StorageDead(_13);
+          StorageLive(_15);
+          StorageLive(_16);
+          _16 = copy _4;
+          StorageLive(_17);
+          _17 = copy _5;
+-         _15 = slice_get_unchecked::<*mut i64, *mut [i64], i64>(move _16, move _17) -> [return: bb4, unwind unreachable];
++         _15 = &raw mut (*_16)[_17];
++         goto -> bb4;
+      }
+  
+      bb4: {
+          StorageDead(_17);
+          StorageDead(_16);
+          _0 = (move _6, move _9, move _12, move _15);
+          StorageDead(_15);
+          StorageDead(_12);
+          StorageDead(_9);
+          StorageDead(_6);
+          return;
+      }
+  }
+  
diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-abort.mir b/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-abort.mir
index ec67193bc794..d1b1e3d7dd73 100644
--- a/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-abort.mir
+++ b/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-abort.mir
@@ -8,19 +8,11 @@ fn slice_get_mut_usize(_1: &mut [u32], _2: usize) -> Option<&mut u32> {
         scope 2 (inlined <usize as SliceIndex<[u32]>>::get_mut) {
             let mut _3: usize;
             let mut _4: bool;
-            let mut _5: *mut [u32];
-            let mut _7: *mut u32;
-            let mut _8: &mut u32;
-            scope 3 (inlined core::slice::index::get_mut_noubcheck::<u32>) {
-                let _6: *mut u32;
-                scope 4 {
-                }
-            }
+            let mut _5: &mut u32;
         }
     }
 
     bb0: {
-        StorageLive(_8);
         StorageLive(_4);
         StorageLive(_3);
         _3 = PtrMetadata(copy _1);
@@ -36,23 +28,15 @@ fn slice_get_mut_usize(_1: &mut [u32], _2: usize) -> Option<&mut u32> {
 
     bb2: {
         StorageDead(_3);
-        StorageLive(_7);
         StorageLive(_5);
-        _5 = &raw mut (*_1);
-        StorageLive(_6);
-        _6 = copy _5 as *mut u32 (PtrToPtr);
-        _7 = Offset(copy _6, copy _2);
-        StorageDead(_6);
+        _5 = &mut (*_1)[_2];
+        _0 = Option::<&mut u32>::Some(move _5);
         StorageDead(_5);
-        _8 = &mut (*_7);
-        _0 = Option::<&mut u32>::Some(copy _8);
-        StorageDead(_7);
         goto -> bb3;
     }
 
     bb3: {
         StorageDead(_4);
-        StorageDead(_8);
         return;
     }
 }
diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-unwind.mir b/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-unwind.mir
index ec67193bc794..d1b1e3d7dd73 100644
--- a/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-unwind.mir
+++ b/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-unwind.mir
@@ -8,19 +8,11 @@ fn slice_get_mut_usize(_1: &mut [u32], _2: usize) -> Option<&mut u32> {
         scope 2 (inlined <usize as SliceIndex<[u32]>>::get_mut) {
             let mut _3: usize;
             let mut _4: bool;
-            let mut _5: *mut [u32];
-            let mut _7: *mut u32;
-            let mut _8: &mut u32;
-            scope 3 (inlined core::slice::index::get_mut_noubcheck::<u32>) {
-                let _6: *mut u32;
-                scope 4 {
-                }
-            }
+            let mut _5: &mut u32;
         }
     }
 
     bb0: {
-        StorageLive(_8);
         StorageLive(_4);
         StorageLive(_3);
         _3 = PtrMetadata(copy _1);
@@ -36,23 +28,15 @@ fn slice_get_mut_usize(_1: &mut [u32], _2: usize) -> Option<&mut u32> {
 
     bb2: {
         StorageDead(_3);
-        StorageLive(_7);
         StorageLive(_5);
-        _5 = &raw mut (*_1);
-        StorageLive(_6);
-        _6 = copy _5 as *mut u32 (PtrToPtr);
-        _7 = Offset(copy _6, copy _2);
-        StorageDead(_6);
+        _5 = &mut (*_1)[_2];
+        _0 = Option::<&mut u32>::Some(move _5);
         StorageDead(_5);
-        _8 = &mut (*_7);
-        _0 = Option::<&mut u32>::Some(copy _8);
-        StorageDead(_7);
         goto -> bb3;
     }
 
     bb3: {
         StorageDead(_4);
-        StorageDead(_8);
         return;
     }
 }
diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-abort.mir b/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-abort.mir
index 597f02e837ab..6fb1637a6e02 100644
--- a/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-abort.mir
+++ b/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-abort.mir
@@ -15,12 +15,10 @@ fn slice_get_unchecked_mut_range(_1: &mut [u32], _2: std::ops::Range<usize>) ->
             let _8: usize;
             scope 3 {
                 scope 6 (inlined core::slice::index::get_offset_len_mut_noubcheck::<u32>) {
-                    let _10: *mut u32;
+                    let _9: *mut u32;
                     scope 7 {
-                    }
-                    scope 8 (inlined core::slice::index::get_mut_noubcheck::<u32>) {
-                        let _9: *mut u32;
-                        scope 9 {
+                        let _10: *mut u32;
+                        scope 8 {
                         }
                     }
                 }
@@ -47,13 +45,13 @@ fn slice_get_unchecked_mut_range(_1: &mut [u32], _2: std::ops::Range<usize>) ->
     bb1: {
         StorageDead(_6);
         _8 = SubUnchecked(copy _4, copy _3);
-        StorageLive(_10);
         StorageLive(_9);
+        StorageLive(_10);
         _9 = copy _5 as *mut u32 (PtrToPtr);
         _10 = Offset(copy _9, copy _3);
-        StorageDead(_9);
         _11 = *mut [u32] from (copy _10, copy _8);
         StorageDead(_10);
+        StorageDead(_9);
         StorageDead(_8);
         StorageDead(_5);
         _0 = &mut (*_11);
diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-unwind.mir b/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-unwind.mir
index 597f02e837ab..6fb1637a6e02 100644
--- a/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-unwind.mir
+++ b/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-unwind.mir
@@ -15,12 +15,10 @@ fn slice_get_unchecked_mut_range(_1: &mut [u32], _2: std::ops::Range<usize>) ->
             let _8: usize;
             scope 3 {
                 scope 6 (inlined core::slice::index::get_offset_len_mut_noubcheck::<u32>) {
-                    let _10: *mut u32;
+                    let _9: *mut u32;
                     scope 7 {
-                    }
-                    scope 8 (inlined core::slice::index::get_mut_noubcheck::<u32>) {
-                        let _9: *mut u32;
-                        scope 9 {
+                        let _10: *mut u32;
+                        scope 8 {
                         }
                     }
                 }
@@ -47,13 +45,13 @@ fn slice_get_unchecked_mut_range(_1: &mut [u32], _2: std::ops::Range<usize>) ->
     bb1: {
         StorageDead(_6);
         _8 = SubUnchecked(copy _4, copy _3);
-        StorageLive(_10);
         StorageLive(_9);
+        StorageLive(_10);
         _9 = copy _5 as *mut u32 (PtrToPtr);
         _10 = Offset(copy _9, copy _3);
-        StorageDead(_9);
         _11 = *mut [u32] from (copy _10, copy _8);
         StorageDead(_10);
+        StorageDead(_9);
         StorageDead(_8);
         StorageDead(_5);
         _0 = &mut (*_11);
diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-abort.mir b/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-abort.mir
index e34723898e4a..ad1ca5dff43a 100644
--- a/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-abort.mir
+++ b/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-abort.mir
@@ -13,12 +13,10 @@ fn slice_ptr_get_unchecked_range(_1: *const [u32], _2: std::ops::Range<usize>) -
             let _7: usize;
             scope 3 {
                 scope 6 (inlined core::slice::index::get_offset_len_noubcheck::<u32>) {
-                    let _9: *const u32;
+                    let _8: *const u32;
                     scope 7 {
-                    }
-                    scope 8 (inlined core::slice::index::get_noubcheck::<u32>) {
-                        let _8: *const u32;
-                        scope 9 {
+                        let _9: *const u32;
+                        scope 8 {
                         }
                     }
                 }
@@ -42,13 +40,13 @@ fn slice_ptr_get_unchecked_range(_1: *const [u32], _2: std::ops::Range<usize>) -
     bb1: {
         StorageDead(_5);
         _7 = SubUnchecked(copy _4, copy _3);
-        StorageLive(_9);
         StorageLive(_8);
+        StorageLive(_9);
         _8 = copy _1 as *const u32 (PtrToPtr);
         _9 = Offset(copy _8, copy _3);
-        StorageDead(_8);
         _0 = *const [u32] from (copy _9, copy _7);
         StorageDead(_9);
+        StorageDead(_8);
         StorageDead(_7);
         return;
     }
diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-unwind.mir b/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-unwind.mir
index e34723898e4a..ad1ca5dff43a 100644
--- a/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-unwind.mir
+++ b/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-unwind.mir
@@ -13,12 +13,10 @@ fn slice_ptr_get_unchecked_range(_1: *const [u32], _2: std::ops::Range<usize>) -
             let _7: usize;
             scope 3 {
                 scope 6 (inlined core::slice::index::get_offset_len_noubcheck::<u32>) {
-                    let _9: *const u32;
+                    let _8: *const u32;
                     scope 7 {
-                    }
-                    scope 8 (inlined core::slice::index::get_noubcheck::<u32>) {
-                        let _8: *const u32;
-                        scope 9 {
+                        let _9: *const u32;
+                        scope 8 {
                         }
                     }
                 }
@@ -42,13 +40,13 @@ fn slice_ptr_get_unchecked_range(_1: *const [u32], _2: std::ops::Range<usize>) -
     bb1: {
         StorageDead(_5);
         _7 = SubUnchecked(copy _4, copy _3);
-        StorageLive(_9);
         StorageLive(_8);
+        StorageLive(_9);
         _8 = copy _1 as *const u32 (PtrToPtr);
         _9 = Offset(copy _8, copy _3);
-        StorageDead(_8);
         _0 = *const [u32] from (copy _9, copy _7);
         StorageDead(_9);
+        StorageDead(_8);
         StorageDead(_7);
         return;
     }
diff --git a/tests/ui/cast/func-pointer-issue-140491.rs b/tests/ui/cast/func-pointer-issue-140491.rs
new file mode 100644
index 000000000000..d5d86a66f5a9
--- /dev/null
+++ b/tests/ui/cast/func-pointer-issue-140491.rs
@@ -0,0 +1,7 @@
+fn my_fn(event: &Event<'_>) {}
+
+struct Event<'a>(&'a ());
+
+fn main() {
+    const ptr: &fn(&Event<'_>) = &my_fn as _; //~ ERROR non-primitive cast: `&for<'a, 'b> fn(&'a Event<'b>) {my_fn}` as `&for<'a, 'b> fn(&'a Event<'b>)` [E0605]
+}
diff --git a/tests/ui/cast/func-pointer-issue-140491.stderr b/tests/ui/cast/func-pointer-issue-140491.stderr
new file mode 100644
index 000000000000..e1c07010e691
--- /dev/null
+++ b/tests/ui/cast/func-pointer-issue-140491.stderr
@@ -0,0 +1,11 @@
+error[E0605]: non-primitive cast: `&for<'a, 'b> fn(&'a Event<'b>) {my_fn}` as `&for<'a, 'b> fn(&'a Event<'b>)`
+  --> $DIR/func-pointer-issue-140491.rs:6:34
+   |
+LL | ..._>) = &my_fn as _;
+   |          ^^^^^^^^^^^ an `as` expression can only be used to convert between primitive types or to coerce to a specific trait object
+   |
+   = note: casting reference expression `&my_fn` because `&` binds tighter than `as`
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0605`.
diff --git a/tests/ui/coercion/issue-73886.stderr b/tests/ui/coercion/issue-73886.stderr
index 0d4c90017cf1..a287aa29e118 100644
--- a/tests/ui/coercion/issue-73886.stderr
+++ b/tests/ui/coercion/issue-73886.stderr
@@ -3,6 +3,8 @@ error[E0605]: non-primitive cast: `&&[i32; 1]` as `&[_]`
    |
 LL |     let _ = &&[0] as &[_];
    |             ^^^^^^^^^^^^^ an `as` expression can only be used to convert between primitive types or to coerce to a specific trait object
+   |
+   = note: casting reference expression `&&[0]` because `&` binds tighter than `as`
 
 error[E0605]: non-primitive cast: `u32` as `Option<_>`
   --> $DIR/issue-73886.rs:4:13
diff --git a/tests/ui/threads-sendsync/tls-dont-move-after-init.rs b/tests/ui/threads-sendsync/tls-dont-move-after-init.rs
new file mode 100644
index 000000000000..54fcc32e9bd7
--- /dev/null
+++ b/tests/ui/threads-sendsync/tls-dont-move-after-init.rs
@@ -0,0 +1,37 @@
+//@ run-pass
+//@ needs-threads
+
+use std::cell::Cell;
+use std::thread;
+
+#[derive(Default)]
+struct Foo {
+    ptr: Cell<*const Foo>,
+}
+
+impl Foo {
+    fn touch(&self) {
+        if self.ptr.get().is_null() {
+            self.ptr.set(self);
+        } else {
+            assert!(self.ptr.get() == self);
+        }
+    }
+}
+
+impl Drop for Foo {
+    fn drop(&mut self) {
+        self.touch();
+    }
+}
+
+thread_local!(static FOO: Foo = Foo::default());
+
+fn main() {
+    thread::spawn(|| {
+        FOO.with(|foo| foo.touch());
+        FOO.with(|foo| foo.touch());
+    })
+    .join()
+    .unwrap();
+}
diff --git a/tests/ui/typeck/consider-borrowing-141810-1.rs b/tests/ui/typeck/consider-borrowing-141810-1.rs
new file mode 100644
index 000000000000..94c2d6909151
--- /dev/null
+++ b/tests/ui/typeck/consider-borrowing-141810-1.rs
@@ -0,0 +1,9 @@
+fn main() {
+    let x = if true {
+        &true
+    } else if false { //~ ERROR `if` and `else` have incompatible types [E0308]
+        true //~ HELP consider borrowing here
+    } else {
+        true
+    };
+}
diff --git a/tests/ui/typeck/consider-borrowing-141810-1.stderr b/tests/ui/typeck/consider-borrowing-141810-1.stderr
new file mode 100644
index 000000000000..9291721ac712
--- /dev/null
+++ b/tests/ui/typeck/consider-borrowing-141810-1.stderr
@@ -0,0 +1,28 @@
+error[E0308]: `if` and `else` have incompatible types
+  --> $DIR/consider-borrowing-141810-1.rs:4:12
+   |
+LL |        let x = if true {
+   |  ______________-
+LL | |          &true
+   | |          ----- expected because of this
+LL | |      } else if false {
+   | | ____________^
+LL | ||         true
+LL | ||     } else {
+LL | ||         true
+LL | ||     };
+   | ||     ^
+   | ||_____|
+   |  |_____`if` and `else` have incompatible types
+   |        expected `&bool`, found `bool`
+   |
+help: consider borrowing here
+   |
+LL ~         &true
+LL |     } else {
+LL ~         &true
+   |
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/tests/ui/typeck/consider-borrowing-141810-2.rs b/tests/ui/typeck/consider-borrowing-141810-2.rs
new file mode 100644
index 000000000000..e32e689efb7e
--- /dev/null
+++ b/tests/ui/typeck/consider-borrowing-141810-2.rs
@@ -0,0 +1,8 @@
+fn main() {
+    let x = if true {
+        &()
+    } else if false { //~ ERROR `if` and `else` have incompatible types [E0308]
+    } else {
+    };
+
+}
diff --git a/tests/ui/typeck/consider-borrowing-141810-2.stderr b/tests/ui/typeck/consider-borrowing-141810-2.stderr
new file mode 100644
index 000000000000..dd229897283b
--- /dev/null
+++ b/tests/ui/typeck/consider-borrowing-141810-2.stderr
@@ -0,0 +1,19 @@
+error[E0308]: `if` and `else` have incompatible types
+  --> $DIR/consider-borrowing-141810-2.rs:4:12
+   |
+LL |        let x = if true {
+   |  ______________-
+LL | |          &()
+   | |          --- expected because of this
+LL | |      } else if false {
+   | | ____________^
+LL | ||     } else {
+LL | ||     };
+   | ||     ^
+   | ||_____|
+   |  |_____`if` and `else` have incompatible types
+   |        expected `&()`, found `()`
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/tests/ui/typeck/consider-borrowing-141810-3.rs b/tests/ui/typeck/consider-borrowing-141810-3.rs
new file mode 100644
index 000000000000..d38828de7c17
--- /dev/null
+++ b/tests/ui/typeck/consider-borrowing-141810-3.rs
@@ -0,0 +1,7 @@
+fn main() {
+    let x = if true {
+        &()
+    } else if false { //~ ERROR `if` and `else` have incompatible types [E0308]
+
+    };
+}
diff --git a/tests/ui/typeck/consider-borrowing-141810-3.stderr b/tests/ui/typeck/consider-borrowing-141810-3.stderr
new file mode 100644
index 000000000000..0b0c5f191a0d
--- /dev/null
+++ b/tests/ui/typeck/consider-borrowing-141810-3.stderr
@@ -0,0 +1,22 @@
+error[E0308]: `if` and `else` have incompatible types
+  --> $DIR/consider-borrowing-141810-3.rs:4:12
+   |
+LL |        let x = if true {
+   |  ______________-
+LL | |          &()
+   | |          --- expected because of this
+LL | |      } else if false {
+   | | ____________^
+LL | ||
+LL | ||     };
+   | ||     ^
+   | ||_____|
+   |  |_____`if` and `else` have incompatible types
+   |        expected `&()`, found `()`
+   |
+   = note: `if` expressions without `else` evaluate to `()`
+   = note: consider adding an `else` block that evaluates to the expected type
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/tests/ui/typeck/consider-borrowing-141810-4.rs b/tests/ui/typeck/consider-borrowing-141810-4.rs
new file mode 100644
index 000000000000..754af7920a85
--- /dev/null
+++ b/tests/ui/typeck/consider-borrowing-141810-4.rs
@@ -0,0 +1,11 @@
+fn baz(x: &String) {}
+
+fn bar() {
+    baz({
+        String::from("hi") //~ ERROR mismatched types
+    });
+}
+
+fn main() {
+    bar();
+}
diff --git a/tests/ui/typeck/consider-borrowing-141810-4.stderr b/tests/ui/typeck/consider-borrowing-141810-4.stderr
new file mode 100644
index 000000000000..80869d4a5d5c
--- /dev/null
+++ b/tests/ui/typeck/consider-borrowing-141810-4.stderr
@@ -0,0 +1,14 @@
+error[E0308]: mismatched types
+  --> $DIR/consider-borrowing-141810-4.rs:5:9
+   |
+LL |         String::from("hi")
+   |         ^^^^^^^^^^^^^^^^^^ expected `&String`, found `String`
+   |
+help: consider borrowing here
+   |
+LL |         &String::from("hi")
+   |         +
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0308`.