Merging upstream version 1.69.0+dfsg1.

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

7 files changed, 476 insertions, 68 deletions

diff --git a/compiler/rustc_hir/src/def.rs b/compiler/rustc_hir/src/def.rs
index cca5ead0f..8c58129c8 100644
--- a/compiler/rustc_hir/src/def.rs
+++ b/compiler/rustc_hir/src/def.rs
@@ -2,6 +2,8 @@ use crate::hir;
 
 use rustc_ast as ast;
 use rustc_ast::NodeId;
+use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::stable_hasher::ToStableHashKey;
 use rustc_macros::HashStable_Generic;
 use rustc_span::def_id::{DefId, LocalDefId};
 use rustc_span::hygiene::MacroKind;
@@ -114,12 +116,19 @@ pub enum DefKind {
     LifetimeParam,
     /// A use of `global_asm!`.
     GlobalAsm,
-    Impl,
+    Impl {
+        of_trait: bool,
+    },
     Closure,
     Generator,
 }
 
 impl DefKind {
+    /// Get an English description for the item's kind.
+    ///
+    /// If you have access to `TyCtxt`, use `TyCtxt::def_descr` or
+    /// `TyCtxt::def_kind_descr` instead, because they give better
+    /// information for generators and associated functions.
     pub fn descr(self, def_id: DefId) -> &'static str {
         match self {
             DefKind::Fn => "function",
@@ -153,7 +162,7 @@ impl DefKind {
             DefKind::AnonConst => "constant expression",
             DefKind::InlineConst => "inline constant",
             DefKind::Field => "field",
-            DefKind::Impl => "implementation",
+            DefKind::Impl { .. } => "implementation",
             DefKind::Closure => "closure",
             DefKind::Generator => "generator",
             DefKind::ExternCrate => "extern crate",
@@ -162,6 +171,10 @@ impl DefKind {
     }
 
     /// Gets an English article for the definition.
+    ///
+    /// If you have access to `TyCtxt`, use `TyCtxt::def_descr_article` or
+    /// `TyCtxt::def_kind_descr_article` instead, because they give better
+    /// information for generators and associated functions.
     pub fn article(&self) -> &'static str {
         match *self {
             DefKind::AssocTy
@@ -169,7 +182,7 @@ impl DefKind {
             | DefKind::AssocFn
             | DefKind::Enum
             | DefKind::OpaqueTy
-            | DefKind::Impl
+            | DefKind::Impl { .. }
             | DefKind::Use
             | DefKind::InlineConst
             | DefKind::ExternCrate => "an",
@@ -214,7 +227,7 @@ impl DefKind {
             | DefKind::Use
             | DefKind::ForeignMod
             | DefKind::GlobalAsm
-            | DefKind::Impl
+            | DefKind::Impl { .. }
             | DefKind::ImplTraitPlaceholder => None,
         }
     }
@@ -253,7 +266,7 @@ impl DefKind {
             | DefKind::ForeignMod
             | DefKind::OpaqueTy
             | DefKind::ImplTraitPlaceholder
-            | DefKind::Impl
+            | DefKind::Impl { .. }
             | DefKind::Field
             | DefKind::TyParam
             | DefKind::ConstParam
@@ -472,7 +485,8 @@ impl PartialRes {
 
 /// Different kinds of symbols can coexist even if they share the same textual name.
 /// Therefore, they each have a separate universe (known as a "namespace").
-#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
+#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug, Encodable, Decodable)]
+#[derive(HashStable_Generic)]
 pub enum Namespace {
     /// The type namespace includes `struct`s, `enum`s, `union`s, `trait`s, and `mod`s
     /// (and, by extension, crates).
@@ -499,6 +513,15 @@ impl Namespace {
     }
 }
 
+impl<CTX: crate::HashStableContext> ToStableHashKey<CTX> for Namespace {
+    type KeyType = Namespace;
+
+    #[inline]
+    fn to_stable_hash_key(&self, _: &CTX) -> Namespace {
+        *self
+    }
+}
+
 /// Just a helper ‒ separate structure for each namespace.
 #[derive(Copy, Clone, Default, Debug)]
 pub struct PerNS<T> {
@@ -760,3 +783,5 @@ pub enum LifetimeRes {
     /// HACK: This is used to recover the NodeId of an elided lifetime.
     ElidedAnchor { start: NodeId, end: NodeId },
 }
+
+pub type DocLinkResMap = FxHashMap<(Symbol, Namespace), Option<Res<NodeId>>>;
diff --git a/compiler/rustc_hir/src/definitions.rs b/compiler/rustc_hir/src/definitions.rs
index 21cf214e4..8ceb17649 100644
--- a/compiler/rustc_hir/src/definitions.rs
+++ b/compiler/rustc_hir/src/definitions.rs
@@ -92,7 +92,7 @@ impl DefPathTable {
 /// The definition table containing node definitions.
 /// It holds the `DefPathTable` for `LocalDefId`s/`DefPath`s.
 /// It also stores mappings to convert `LocalDefId`s to/from `HirId`s.
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 pub struct Definitions {
     table: DefPathTable,
     next_disambiguator: FxHashMap<(LocalDefId, DefPathData), u32>,
@@ -280,6 +280,8 @@ pub enum DefPathData {
     AnonConst,
     /// An `impl Trait` type node.
     ImplTrait,
+    /// `impl Trait` generated associated type node.
+    ImplTraitAssocTy,
 }
 
 impl Definitions {
@@ -403,7 +405,7 @@ impl DefPathData {
             TypeNs(name) | ValueNs(name) | MacroNs(name) | LifetimeNs(name) => Some(name),
 
             Impl | ForeignMod | CrateRoot | Use | GlobalAsm | ClosureExpr | Ctor | AnonConst
-            | ImplTrait => None,
+            | ImplTrait | ImplTraitAssocTy => None,
         }
     }
 
@@ -422,7 +424,7 @@ impl DefPathData {
             ClosureExpr => DefPathDataName::Anon { namespace: sym::closure },
             Ctor => DefPathDataName::Anon { namespace: sym::constructor },
             AnonConst => DefPathDataName::Anon { namespace: sym::constant },
-            ImplTrait => DefPathDataName::Anon { namespace: sym::opaque },
+            ImplTrait | ImplTraitAssocTy => DefPathDataName::Anon { namespace: sym::opaque },
         }
     }
 }
diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs
index d6566860f..19d3d41c9 100644
--- a/compiler/rustc_hir/src/hir.rs
+++ b/compiler/rustc_hir/src/hir.rs
@@ -369,10 +369,10 @@ impl<'hir> GenericArgs<'hir> {
 
     pub fn has_err(&self) -> bool {
         self.args.iter().any(|arg| match arg {
-            GenericArg::Type(ty) => matches!(ty.kind, TyKind::Err),
+            GenericArg::Type(ty) => matches!(ty.kind, TyKind::Err(_)),
             _ => false,
         }) || self.bindings.iter().any(|arg| match arg.kind {
-            TypeBindingKind::Equality { term: Term::Ty(ty) } => matches!(ty.kind, TyKind::Err),
+            TypeBindingKind::Equality { term: Term::Ty(ty) } => matches!(ty.kind, TyKind::Err(_)),
             _ => false,
         })
     }
@@ -498,6 +498,7 @@ pub struct GenericParam<'hir> {
     pub pure_wrt_drop: bool,
     pub kind: GenericParamKind<'hir>,
     pub colon_span: Option<Span>,
+    pub source: GenericParamSource,
 }
 
 impl<'hir> GenericParam<'hir> {
@@ -516,6 +517,20 @@ impl<'hir> GenericParam<'hir> {
     }
 }
 
+/// Records where the generic parameter originated from.
+///
+/// This can either be from an item's generics, in which case it's typically
+/// early-bound (but can be a late-bound lifetime in functions, for example),
+/// or from a `for<...>` binder, in which case it's late-bound (and notably,
+/// does not show up in the parent item's generics).
+#[derive(Debug, HashStable_Generic, PartialEq, Eq, Copy, Clone)]
+pub enum GenericParamSource {
+    // Early or late-bound parameters defined on an item
+    Generics,
+    // Late-bound parameters defined via a `for<...>`
+    Binder,
+}
+
 #[derive(Default)]
 pub struct GenericParamCount {
     pub lifetimes: usize,
@@ -574,14 +589,11 @@ impl<'hir> Generics<'hir> {
 
     /// If there are generic parameters, return where to introduce a new one.
     pub fn span_for_param_suggestion(&self) -> Option<Span> {
-        if self.params.iter().any(|p| self.span.contains(p.span)) {
+        self.params.iter().any(|p| self.span.contains(p.span)).then(|| {
             // `fn foo<A>(t: impl Trait)`
             //          ^ suggest `, T: Trait` here
-            let span = self.span.with_lo(self.span.hi() - BytePos(1)).shrink_to_lo();
-            Some(span)
-        } else {
-            None
-        }
+            self.span.with_lo(self.span.hi() - BytePos(1)).shrink_to_lo()
+        })
     }
 
     /// `Span` where further predicates would be suggested, accounting for trailing commas, like
@@ -639,7 +651,7 @@ impl<'hir> Generics<'hir> {
                 // We include bounds that come from a `#[derive(_)]` but point at the user's code,
                 // as we use this method to get a span appropriate for suggestions.
                 let bs = bound.span();
-                if bs.can_be_used_for_suggestions() { Some(bs.shrink_to_hi()) } else { None }
+                bs.can_be_used_for_suggestions().then(|| bs.shrink_to_hi())
             },
         )
     }
@@ -831,8 +843,6 @@ pub struct OwnerNodes<'tcx> {
     pub nodes: IndexVec<ItemLocalId, Option<ParentedNode<'tcx>>>,
     /// Content of local bodies.
     pub bodies: SortedMap<ItemLocalId, &'tcx Body<'tcx>>,
-    /// Non-owning definitions contained in this owner.
-    pub local_id_to_def_id: SortedMap<ItemLocalId, LocalDefId>,
 }
 
 impl<'tcx> OwnerNodes<'tcx> {
@@ -862,7 +872,6 @@ impl fmt::Debug for OwnerNodes<'_> {
                     .collect::<Vec<_>>(),
             )
             .field("bodies", &self.bodies)
-            .field("local_id_to_def_id", &self.local_id_to_def_id)
             .field("hash_without_bodies", &self.hash_without_bodies)
             .field("hash_including_bodies", &self.hash_including_bodies)
             .finish()
@@ -993,7 +1002,6 @@ pub struct Pat<'hir> {
 }
 
 impl<'hir> Pat<'hir> {
-    // FIXME(#19596) this is a workaround, but there should be a better way
     fn walk_short_(&self, it: &mut impl FnMut(&Pat<'hir>) -> bool) -> bool {
         if !it(self) {
             return false;
@@ -1021,7 +1029,6 @@ impl<'hir> Pat<'hir> {
         self.walk_short_(&mut it)
     }
 
-    // FIXME(#19596) this is a workaround, but there should be a better way
     fn walk_(&self, it: &mut impl FnMut(&Pat<'hir>) -> bool) {
         if !it(self) {
             return;
@@ -1696,7 +1703,7 @@ impl Expr<'_> {
             ExprKind::Struct(..) => ExprPrecedence::Struct,
             ExprKind::Repeat(..) => ExprPrecedence::Repeat,
             ExprKind::Yield(..) => ExprPrecedence::Yield,
-            ExprKind::Err => ExprPrecedence::Err,
+            ExprKind::Err(_) => ExprPrecedence::Err,
         }
     }
 
@@ -1762,7 +1769,7 @@ impl Expr<'_> {
             | ExprKind::Yield(..)
             | ExprKind::Cast(..)
             | ExprKind::DropTemps(..)
-            | ExprKind::Err => false,
+            | ExprKind::Err(_) => false,
         }
     }
 
@@ -1848,7 +1855,7 @@ impl Expr<'_> {
             | ExprKind::Binary(..)
             | ExprKind::Yield(..)
             | ExprKind::DropTemps(..)
-            | ExprKind::Err => true,
+            | ExprKind::Err(_) => true,
         }
     }
 
@@ -2021,7 +2028,7 @@ pub enum ExprKind<'hir> {
     Yield(&'hir Expr<'hir>, YieldSource),
 
     /// A placeholder for an expression that wasn't syntactically well formed in some way.
-    Err,
+    Err(rustc_span::ErrorGuaranteed),
 }
 
 /// Represents an optionally `Self`-qualified value/type path or associated extension.
@@ -2106,8 +2113,8 @@ pub enum LocalSource {
 }
 
 /// Hints at the original code for a `match _ { .. }`.
-#[derive(Copy, Clone, PartialEq, Eq, Encodable, Hash, Debug)]
-#[derive(HashStable_Generic)]
+#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
+#[derive(HashStable_Generic, Encodable, Decodable)]
 pub enum MatchSource {
     /// A `match _ { .. }`.
     Normal,
@@ -2117,6 +2124,8 @@ pub enum MatchSource {
     TryDesugar,
     /// A desugared `<expr>.await`.
     AwaitDesugar,
+    /// A desugared `format_args!()`.
+    FormatArgs,
 }
 
 impl MatchSource {
@@ -2128,6 +2137,7 @@ impl MatchSource {
             ForLoopDesugar => "for",
             TryDesugar => "?",
             AwaitDesugar => ".await",
+            FormatArgs => "format_args!()",
         }
     }
 }
@@ -2263,7 +2273,7 @@ pub struct TraitItem<'hir> {
     pub defaultness: Defaultness,
 }
 
-impl TraitItem<'_> {
+impl<'hir> TraitItem<'hir> {
     #[inline]
     pub fn hir_id(&self) -> HirId {
         // Items are always HIR owners.
@@ -2273,6 +2283,32 @@ impl TraitItem<'_> {
     pub fn trait_item_id(&self) -> TraitItemId {
         TraitItemId { owner_id: self.owner_id }
     }
+
+    /// Expect an [`TraitItemKind::Const`] or panic.
+    #[track_caller]
+    pub fn expect_const(&self) -> (&'hir Ty<'hir>, Option<BodyId>) {
+        let TraitItemKind::Const(ty, body) = self.kind else { self.expect_failed("a constant") };
+        (ty, body)
+    }
+
+    /// Expect an [`TraitItemKind::Fn`] or panic.
+    #[track_caller]
+    pub fn expect_fn(&self) -> (&FnSig<'hir>, &TraitFn<'hir>) {
+        let TraitItemKind::Fn(ty, trfn) = &self.kind else { self.expect_failed("a function") };
+        (ty, trfn)
+    }
+
+    /// Expect an [`TraitItemKind::Type`] or panic.
+    #[track_caller]
+    pub fn expect_type(&self) -> (GenericBounds<'hir>, Option<&'hir Ty<'hir>>) {
+        let TraitItemKind::Type(bounds, ty) = self.kind else { self.expect_failed("a type") };
+        (bounds, ty)
+    }
+
+    #[track_caller]
+    fn expect_failed(&self, expected: &'static str) -> ! {
+        panic!("expected {expected} item, found {self:?}")
+    }
 }
 
 /// Represents a trait method's body (or just argument names).
@@ -2325,7 +2361,7 @@ pub struct ImplItem<'hir> {
     pub vis_span: Span,
 }
 
-impl ImplItem<'_> {
+impl<'hir> ImplItem<'hir> {
     #[inline]
     pub fn hir_id(&self) -> HirId {
         // Items are always HIR owners.
@@ -2335,6 +2371,32 @@ impl ImplItem<'_> {
     pub fn impl_item_id(&self) -> ImplItemId {
         ImplItemId { owner_id: self.owner_id }
     }
+
+    /// Expect an [`ImplItemKind::Const`] or panic.
+    #[track_caller]
+    pub fn expect_const(&self) -> (&'hir Ty<'hir>, BodyId) {
+        let ImplItemKind::Const(ty, body) = self.kind else { self.expect_failed("a constant") };
+        (ty, body)
+    }
+
+    /// Expect an [`ImplItemKind::Fn`] or panic.
+    #[track_caller]
+    pub fn expect_fn(&self) -> (&FnSig<'hir>, BodyId) {
+        let ImplItemKind::Fn(ty, body) = &self.kind else { self.expect_failed("a function") };
+        (ty, *body)
+    }
+
+    /// Expect an [`ImplItemKind::Type`] or panic.
+    #[track_caller]
+    pub fn expect_type(&self) -> &'hir Ty<'hir> {
+        let ImplItemKind::Type(ty) = self.kind else { self.expect_failed("a type") };
+        ty
+    }
+
+    #[track_caller]
+    fn expect_failed(&self, expected: &'static str) -> ! {
+        panic!("expected {expected} item, found {self:?}")
+    }
 }
 
 /// Represents various kinds of content within an `impl`.
@@ -2629,7 +2691,7 @@ pub enum TyKind<'hir> {
     /// specified. This can appear anywhere in a type.
     Infer,
     /// Placeholder for a type that has failed to be defined.
-    Err,
+    Err(rustc_span::ErrorGuaranteed),
 }
 
 #[derive(Debug, HashStable_Generic)]
@@ -2995,7 +3057,7 @@ pub struct Item<'hir> {
     pub vis_span: Span,
 }
 
-impl Item<'_> {
+impl<'hir> Item<'hir> {
     #[inline]
     pub fn hir_id(&self) -> HirId {
         // Items are always HIR owners.
@@ -3005,6 +3067,132 @@ impl Item<'_> {
     pub fn item_id(&self) -> ItemId {
         ItemId { owner_id: self.owner_id }
     }
+
+    /// Expect an [`ItemKind::ExternCrate`] or panic.
+    #[track_caller]
+    pub fn expect_extern_crate(&self) -> Option<Symbol> {
+        let ItemKind::ExternCrate(s) = self.kind else { self.expect_failed("an extern crate") };
+        s
+    }
+
+    /// Expect an [`ItemKind::Use`] or panic.
+    #[track_caller]
+    pub fn expect_use(&self) -> (&'hir UsePath<'hir>, UseKind) {
+        let ItemKind::Use(p, uk) = self.kind else { self.expect_failed("a use") };
+        (p, uk)
+    }
+
+    /// Expect an [`ItemKind::Static`] or panic.
+    #[track_caller]
+    pub fn expect_static(&self) -> (&'hir Ty<'hir>, Mutability, BodyId) {
+        let ItemKind::Static(ty, mutbl, body) = self.kind else { self.expect_failed("a static") };
+        (ty, mutbl, body)
+    }
+    /// Expect an [`ItemKind::Const`] or panic.
+    #[track_caller]
+    pub fn expect_const(&self) -> (&'hir Ty<'hir>, BodyId) {
+        let ItemKind::Const(ty, body) = self.kind else { self.expect_failed("a constant") };
+        (ty, body)
+    }
+    /// Expect an [`ItemKind::Fn`] or panic.
+    #[track_caller]
+    pub fn expect_fn(&self) -> (&FnSig<'hir>, &'hir Generics<'hir>, BodyId) {
+        let ItemKind::Fn(sig, gen, body) = &self.kind else { self.expect_failed("a function") };
+        (sig, gen, *body)
+    }
+
+    /// Expect an [`ItemKind::Macro`] or panic.
+    #[track_caller]
+    pub fn expect_macro(&self) -> (&ast::MacroDef, MacroKind) {
+        let ItemKind::Macro(def, mk) = &self.kind else { self.expect_failed("a macro") };
+        (def, *mk)
+    }
+
+    /// Expect an [`ItemKind::Mod`] or panic.
+    #[track_caller]
+    pub fn expect_mod(&self) -> &'hir Mod<'hir> {
+        let ItemKind::Mod(m) = self.kind else { self.expect_failed("a module") };
+        m
+    }
+
+    /// Expect an [`ItemKind::ForeignMod`] or panic.
+    #[track_caller]
+    pub fn expect_foreign_mod(&self) -> (Abi, &'hir [ForeignItemRef]) {
+        let ItemKind::ForeignMod { abi, items } = self.kind else { self.expect_failed("a foreign module") };
+        (abi, items)
+    }
+
+    /// Expect an [`ItemKind::GlobalAsm`] or panic.
+    #[track_caller]
+    pub fn expect_global_asm(&self) -> &'hir InlineAsm<'hir> {
+        let ItemKind::GlobalAsm(asm) = self.kind else { self.expect_failed("a global asm") };
+        asm
+    }
+
+    /// Expect an [`ItemKind::TyAlias`] or panic.
+    #[track_caller]
+    pub fn expect_ty_alias(&self) -> (&'hir Ty<'hir>, &'hir Generics<'hir>) {
+        let ItemKind::TyAlias(ty, gen) = self.kind else { self.expect_failed("a type alias") };
+        (ty, gen)
+    }
+
+    /// An opaque `impl Trait` type alias, e.g., `type Foo = impl Bar;`.
+    /// Expect an [`ItemKind::OpaqueTy`] or panic.
+    #[track_caller]
+    pub fn expect_opaque_ty(&self) -> &OpaqueTy<'hir> {
+        let ItemKind::OpaqueTy(ty) = &self.kind else { self.expect_failed("an opaque type") };
+        ty
+    }
+
+    /// Expect an [`ItemKind::Enum`] or panic.
+    #[track_caller]
+    pub fn expect_enum(&self) -> (&EnumDef<'hir>, &'hir Generics<'hir>) {
+        let ItemKind::Enum(def, gen) = &self.kind else { self.expect_failed("an enum") };
+        (def, gen)
+    }
+
+    /// Expect an [`ItemKind::Struct`] or panic.
+    #[track_caller]
+    pub fn expect_struct(&self) -> (&VariantData<'hir>, &'hir Generics<'hir>) {
+        let ItemKind::Struct(data, gen) = &self.kind else { self.expect_failed("a struct") };
+        (data, gen)
+    }
+
+    /// A union definition, e.g., `union Foo<A, B> {x: A, y: B}`.
+    /// Expect an [`ItemKind::Union`] or panic.
+    #[track_caller]
+    pub fn expect_union(&self) -> (&VariantData<'hir>, &'hir Generics<'hir>) {
+        let ItemKind::Union(data, gen) = &self.kind else { self.expect_failed("a union") };
+        (data, gen)
+    }
+
+    /// Expect an [`ItemKind::Trait`] or panic.
+    #[track_caller]
+    pub fn expect_trait(
+        self,
+    ) -> (IsAuto, Unsafety, &'hir Generics<'hir>, GenericBounds<'hir>, &'hir [TraitItemRef]) {
+        let ItemKind::Trait(is_auto, unsafety, gen, bounds, items) = self.kind else { self.expect_failed("a trait") };
+        (is_auto, unsafety, gen, bounds, items)
+    }
+
+    /// Expect an [`ItemKind::TraitAlias`] or panic.
+    #[track_caller]
+    pub fn expect_trait_alias(&self) -> (&'hir Generics<'hir>, GenericBounds<'hir>) {
+        let ItemKind::TraitAlias(gen, bounds) = self.kind else { self.expect_failed("a trait alias") };
+        (gen, bounds)
+    }
+
+    /// Expect an [`ItemKind::Impl`] or panic.
+    #[track_caller]
+    pub fn expect_impl(&self) -> &'hir Impl<'hir> {
+        let ItemKind::Impl(imp) = self.kind else { self.expect_failed("an impl") };
+        imp
+    }
+
+    #[track_caller]
+    fn expect_failed(&self, expected: &'static str) -> ! {
+        panic!("expected {expected} item, found {self:?}")
+    }
 }
 
 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
@@ -3282,7 +3470,7 @@ pub struct Upvar {
 // The TraitCandidate's import_ids is empty if the trait is defined in the same module, and
 // has length > 0 if the trait is found through an chain of imports, starting with the
 // import/use statement in the scope where the trait is used.
-#[derive(Encodable, Decodable, Clone, Debug, HashStable_Generic)]
+#[derive(Encodable, Decodable, Debug, HashStable_Generic)]
 pub struct TraitCandidate {
     pub def_id: DefId,
     pub import_ids: SmallVec<[LocalDefId; 1]>,
@@ -3524,6 +3712,13 @@ impl<'hir> Node<'hir> {
         }
     }
 
+    pub fn alias_ty(self) -> Option<&'hir Ty<'hir>> {
+        match self {
+            Node::Item(Item { kind: ItemKind::TyAlias(ty, ..), .. }) => Some(ty),
+            _ => None,
+        }
+    }
+
     pub fn body_id(&self) -> Option<BodyId> {
         match self {
             Node::TraitItem(TraitItem {
@@ -3590,6 +3785,185 @@ impl<'hir> Node<'hir> {
     pub fn tuple_fields(&self) -> Option<&'hir [FieldDef<'hir>]> {
         if let Node::Ctor(&VariantData::Tuple(fields, _, _)) = self { Some(fields) } else { None }
     }
+
+    /// Expect a [`Node::Param`] or panic.
+    #[track_caller]
+    pub fn expect_param(self) -> &'hir Param<'hir> {
+        let Node::Param(this) = self else { self.expect_failed("a parameter") };
+        this
+    }
+
+    /// Expect a [`Node::Item`] or panic.
+    #[track_caller]
+    pub fn expect_item(self) -> &'hir Item<'hir> {
+        let Node::Item(this) = self else { self.expect_failed("a item") };
+        this
+    }
+
+    /// Expect a [`Node::ForeignItem`] or panic.
+    #[track_caller]
+    pub fn expect_foreign_item(self) -> &'hir ForeignItem<'hir> {
+        let Node::ForeignItem(this) = self else { self.expect_failed("a foreign item") };
+        this
+    }
+
+    /// Expect a [`Node::TraitItem`] or panic.
+    #[track_caller]
+    pub fn expect_trait_item(self) -> &'hir TraitItem<'hir> {
+        let Node::TraitItem(this) = self else { self.expect_failed("a trait item") };
+        this
+    }
+
+    /// Expect a [`Node::ImplItem`] or panic.
+    #[track_caller]
+    pub fn expect_impl_item(self) -> &'hir ImplItem<'hir> {
+        let Node::ImplItem(this) = self else { self.expect_failed("an implementation item") };
+        this
+    }
+
+    /// Expect a [`Node::Variant`] or panic.
+    #[track_caller]
+    pub fn expect_variant(self) -> &'hir Variant<'hir> {
+        let Node::Variant(this) = self else { self.expect_failed("a variant") };
+        this
+    }
+
+    /// Expect a [`Node::Field`] or panic.
+    #[track_caller]
+    pub fn expect_field(self) -> &'hir FieldDef<'hir> {
+        let Node::Field(this) = self else { self.expect_failed("a field definition") };
+        this
+    }
+
+    /// Expect a [`Node::AnonConst`] or panic.
+    #[track_caller]
+    pub fn expect_anon_const(self) -> &'hir AnonConst {
+        let Node::AnonConst(this) = self else { self.expect_failed("an anonymous constant") };
+        this
+    }
+
+    /// Expect a [`Node::Expr`] or panic.
+    #[track_caller]
+    pub fn expect_expr(self) -> &'hir Expr<'hir> {
+        let Node::Expr(this) = self else { self.expect_failed("an expression") };
+        this
+    }
+    /// Expect a [`Node::ExprField`] or panic.
+    #[track_caller]
+    pub fn expect_expr_field(self) -> &'hir ExprField<'hir> {
+        let Node::ExprField(this) = self else { self.expect_failed("an expression field") };
+        this
+    }
+
+    /// Expect a [`Node::Stmt`] or panic.
+    #[track_caller]
+    pub fn expect_stmt(self) -> &'hir Stmt<'hir> {
+        let Node::Stmt(this) = self else { self.expect_failed("a statement") };
+        this
+    }
+
+    /// Expect a [`Node::PathSegment`] or panic.
+    #[track_caller]
+    pub fn expect_path_segment(self) -> &'hir PathSegment<'hir> {
+        let Node::PathSegment(this) = self else { self.expect_failed("a path segment") };
+        this
+    }
+
+    /// Expect a [`Node::Ty`] or panic.
+    #[track_caller]
+    pub fn expect_ty(self) -> &'hir Ty<'hir> {
+        let Node::Ty(this) = self else { self.expect_failed("a type") };
+        this
+    }
+
+    /// Expect a [`Node::TypeBinding`] or panic.
+    #[track_caller]
+    pub fn expect_type_binding(self) -> &'hir TypeBinding<'hir> {
+        let Node::TypeBinding(this) = self else { self.expect_failed("a type binding") };
+        this
+    }
+
+    /// Expect a [`Node::TraitRef`] or panic.
+    #[track_caller]
+    pub fn expect_trait_ref(self) -> &'hir TraitRef<'hir> {
+        let Node::TraitRef(this) = self else { self.expect_failed("a trait reference") };
+        this
+    }
+
+    /// Expect a [`Node::Pat`] or panic.
+    #[track_caller]
+    pub fn expect_pat(self) -> &'hir Pat<'hir> {
+        let Node::Pat(this) = self else { self.expect_failed("a pattern") };
+        this
+    }
+
+    /// Expect a [`Node::PatField`] or panic.
+    #[track_caller]
+    pub fn expect_pat_field(self) -> &'hir PatField<'hir> {
+        let Node::PatField(this) = self else { self.expect_failed("a pattern field") };
+        this
+    }
+
+    /// Expect a [`Node::Arm`] or panic.
+    #[track_caller]
+    pub fn expect_arm(self) -> &'hir Arm<'hir> {
+        let Node::Arm(this) = self else { self.expect_failed("an arm") };
+        this
+    }
+
+    /// Expect a [`Node::Block`] or panic.
+    #[track_caller]
+    pub fn expect_block(self) -> &'hir Block<'hir> {
+        let Node::Block(this) = self else { self.expect_failed("a block") };
+        this
+    }
+
+    /// Expect a [`Node::Local`] or panic.
+    #[track_caller]
+    pub fn expect_local(self) -> &'hir Local<'hir> {
+        let Node::Local(this) = self else { self.expect_failed("a local") };
+        this
+    }
+
+    /// Expect a [`Node::Ctor`] or panic.
+    #[track_caller]
+    pub fn expect_ctor(self) -> &'hir VariantData<'hir> {
+        let Node::Ctor(this) = self else { self.expect_failed("a constructor") };
+        this
+    }
+
+    /// Expect a [`Node::Lifetime`] or panic.
+    #[track_caller]
+    pub fn expect_lifetime(self) -> &'hir Lifetime {
+        let Node::Lifetime(this) = self else { self.expect_failed("a lifetime") };
+        this
+    }
+
+    /// Expect a [`Node::GenericParam`] or panic.
+    #[track_caller]
+    pub fn expect_generic_param(self) -> &'hir GenericParam<'hir> {
+        let Node::GenericParam(this) = self else { self.expect_failed("a generic parameter") };
+        this
+    }
+
+    /// Expect a [`Node::Crate`] or panic.
+    #[track_caller]
+    pub fn expect_crate(self) -> &'hir Mod<'hir> {
+        let Node::Crate(this) = self else { self.expect_failed("a crate") };
+        this
+    }
+
+    /// Expect a [`Node::Infer`] or panic.
+    #[track_caller]
+    pub fn expect_infer(self) -> &'hir InferArg {
+        let Node::Infer(this) = self else { self.expect_failed("an infer") };
+        this
+    }
+
+    #[track_caller]
+    fn expect_failed(&self, expected: &'static str) -> ! {
+        panic!("expected {expected} node, found {self:?}")
+    }
 }
 
 // Some nodes are used a lot. Make sure they don't unintentionally get bigger.
diff --git a/compiler/rustc_hir/src/intravisit.rs b/compiler/rustc_hir/src/intravisit.rs
index 02641b7cf..cc0f64017 100644
--- a/compiler/rustc_hir/src/intravisit.rs
+++ b/compiler/rustc_hir/src/intravisit.rs
@@ -67,6 +67,7 @@
 use crate::hir::*;
 use rustc_ast::walk_list;
 use rustc_ast::{Attribute, Label};
+use rustc_span::def_id::LocalDefId;
 use rustc_span::symbol::{Ident, Symbol};
 use rustc_span::Span;
 
@@ -364,7 +365,7 @@ pub trait Visitor<'v>: Sized {
     fn visit_fn_decl(&mut self, fd: &'v FnDecl<'v>) {
         walk_fn_decl(self, fd)
     }
-    fn visit_fn(&mut self, fk: FnKind<'v>, fd: &'v FnDecl<'v>, b: BodyId, _: Span, id: HirId) {
+    fn visit_fn(&mut self, fk: FnKind<'v>, fd: &'v FnDecl<'v>, b: BodyId, _: Span, id: LocalDefId) {
         walk_fn(self, fk, fd, b, id)
     }
     fn visit_use(&mut self, path: &'v UsePath<'v>, hir_id: HirId) {
@@ -468,13 +469,16 @@ pub fn walk_item<'v, V: Visitor<'v>>(visitor: &mut V, item: &'v Item<'v>) {
             visitor.visit_ty(typ);
             visitor.visit_nested_body(body);
         }
-        ItemKind::Fn(ref sig, ref generics, body_id) => visitor.visit_fn(
-            FnKind::ItemFn(item.ident, generics, sig.header),
-            sig.decl,
-            body_id,
-            item.span,
-            item.hir_id(),
-        ),
+        ItemKind::Fn(ref sig, ref generics, body_id) => {
+            visitor.visit_id(item.hir_id());
+            visitor.visit_fn(
+                FnKind::ItemFn(item.ident, generics, sig.header),
+                sig.decl,
+                body_id,
+                item.span,
+                item.owner_id.def_id,
+            )
+        }
         ItemKind::Macro(..) => {
             visitor.visit_id(item.hir_id());
         }
@@ -733,7 +737,7 @@ pub fn walk_expr<'v, V: Visitor<'v>>(visitor: &mut V, expression: &'v Expr<'v>)
             walk_list!(visitor, visit_arm, arms);
         }
         ExprKind::Closure(&Closure {
-            def_id: _,
+            def_id,
             binder: _,
             bound_generic_params,
             fn_decl,
@@ -745,7 +749,7 @@ pub fn walk_expr<'v, V: Visitor<'v>>(visitor: &mut V, expression: &'v Expr<'v>)
             constness: _,
         }) => {
             walk_list!(visitor, visit_generic_param, bound_generic_params);
-            visitor.visit_fn(FnKind::Closure, fn_decl, body, expression.span, expression.hir_id)
+            visitor.visit_fn(FnKind::Closure, fn_decl, body, expression.span, def_id)
         }
         ExprKind::Block(ref block, ref opt_label) => {
             walk_list!(visitor, visit_label, opt_label);
@@ -786,7 +790,7 @@ pub fn walk_expr<'v, V: Visitor<'v>>(visitor: &mut V, expression: &'v Expr<'v>)
         ExprKind::Yield(ref subexpression, _) => {
             visitor.visit_expr(subexpression);
         }
-        ExprKind::Lit(_) | ExprKind::Err => {}
+        ExprKind::Lit(_) | ExprKind::Err(_) => {}
     }
 }
 
@@ -840,7 +844,7 @@ pub fn walk_ty<'v, V: Visitor<'v>>(visitor: &mut V, typ: &'v Ty<'v>) {
             visitor.visit_lifetime(lifetime);
         }
         TyKind::Typeof(ref expression) => visitor.visit_anon_const(expression),
-        TyKind::Infer | TyKind::Err => {}
+        TyKind::Infer | TyKind::Err(_) => {}
     }
 }
 
@@ -923,9 +927,8 @@ pub fn walk_fn<'v, V: Visitor<'v>>(
     function_kind: FnKind<'v>,
     function_declaration: &'v FnDecl<'v>,
     body_id: BodyId,
-    id: HirId,
+    _: LocalDefId,
 ) {
-    visitor.visit_id(id);
     visitor.visit_fn_decl(function_declaration);
     walk_fn_kind(visitor, function_kind);
     visitor.visit_nested_body(body_id)
@@ -953,26 +956,30 @@ pub fn walk_trait_item<'v, V: Visitor<'v>>(visitor: &mut V, trait_item: &'v Trai
     let TraitItem { ident, generics, ref defaultness, ref kind, span, owner_id: _ } = *trait_item;
     let hir_id = trait_item.hir_id();
     visitor.visit_ident(ident);
-    visitor.visit_generics(generics);
-    visitor.visit_defaultness(defaultness);
+    visitor.visit_generics(&generics);
+    visitor.visit_defaultness(&defaultness);
+    visitor.visit_id(hir_id);
     match *kind {
         TraitItemKind::Const(ref ty, default) => {
-            visitor.visit_id(hir_id);
             visitor.visit_ty(ty);
             walk_list!(visitor, visit_nested_body, default);
         }
         TraitItemKind::Fn(ref sig, TraitFn::Required(param_names)) => {
-            visitor.visit_id(hir_id);
             visitor.visit_fn_decl(sig.decl);
             for &param_name in param_names {
                 visitor.visit_ident(param_name);
             }
         }
         TraitItemKind::Fn(ref sig, TraitFn::Provided(body_id)) => {
-            visitor.visit_fn(FnKind::Method(ident, sig), sig.decl, body_id, span, hir_id);
+            visitor.visit_fn(
+                FnKind::Method(ident, sig),
+                sig.decl,
+                body_id,
+                span,
+                trait_item.owner_id.def_id,
+            );
         }
         TraitItemKind::Type(bounds, ref default) => {
-            visitor.visit_id(hir_id);
             walk_list!(visitor, visit_param_bound, bounds);
             walk_list!(visitor, visit_ty, default);
         }
@@ -1002,9 +1009,9 @@ pub fn walk_impl_item<'v, V: Visitor<'v>>(visitor: &mut V, impl_item: &'v ImplIt
     visitor.visit_ident(ident);
     visitor.visit_generics(generics);
     visitor.visit_defaultness(defaultness);
+    visitor.visit_id(impl_item.hir_id());
     match *kind {
         ImplItemKind::Const(ref ty, body) => {
-            visitor.visit_id(impl_item.hir_id());
             visitor.visit_ty(ty);
             visitor.visit_nested_body(body);
         }
@@ -1014,11 +1021,10 @@ pub fn walk_impl_item<'v, V: Visitor<'v>>(visitor: &mut V, impl_item: &'v ImplIt
                 sig.decl,
                 body_id,
                 impl_item.span,
-                impl_item.hir_id(),
+                impl_item.owner_id.def_id,
             );
         }
         ImplItemKind::Type(ref ty) => {
-            visitor.visit_id(impl_item.hir_id());
             visitor.visit_ty(ty);
         }
     }
diff --git a/compiler/rustc_hir/src/lang_items.rs b/compiler/rustc_hir/src/lang_items.rs
index 54fa5702f..60fa5a99e 100644
--- a/compiler/rustc_hir/src/lang_items.rs
+++ b/compiler/rustc_hir/src/lang_items.rs
@@ -244,6 +244,14 @@ language_item_table! {
     /// libstd panic entry point. Necessary for const eval to be able to catch it
     BeginPanic,              sym::begin_panic,         begin_panic_fn,             Target::Fn,             GenericRequirement::None;
 
+    // Lang items needed for `format_args!()`.
+    FormatAlignment,         sym::format_alignment,    format_alignment,           Target::Enum,           GenericRequirement::None;
+    FormatArgument,          sym::format_argument,     format_argument,            Target::Struct,         GenericRequirement::None;
+    FormatArguments,         sym::format_arguments,    format_arguments,           Target::Struct,         GenericRequirement::None;
+    FormatCount,             sym::format_count,        format_count,               Target::Enum,           GenericRequirement::None;
+    FormatPlaceholder,       sym::format_placeholder,  format_placeholder,         Target::Struct,         GenericRequirement::None;
+    FormatUnsafeArg,         sym::format_unsafe_arg,   format_unsafe_arg,          Target::Struct,         GenericRequirement::None;
+
     ExchangeMalloc,          sym::exchange_malloc,     exchange_malloc_fn,         Target::Fn,             GenericRequirement::None;
     BoxFree,                 sym::box_free,            box_free_fn,                Target::Fn,             GenericRequirement::Minimum(1);
     DropInPlace,             sym::drop_in_place,       drop_in_place_fn,           Target::Fn,             GenericRequirement::Minimum(1);
@@ -279,7 +287,7 @@ language_item_table! {
     TryTraitBranch,          sym::branch,              branch_fn,                  Target::Method(MethodKind::Trait { body: false }), GenericRequirement::None;
     TryTraitFromYeet,        sym::from_yeet,           from_yeet_fn,               Target::Fn,             GenericRequirement::None;
 
-    PointerSized,            sym::pointer_sized,       pointer_sized,              Target::Trait,          GenericRequirement::Exact(0);
+    PointerLike,             sym::pointer_like,        pointer_like,               Target::Trait,          GenericRequirement::Exact(0);
 
     Poll,                    sym::Poll,                poll,                       Target::Enum,           GenericRequirement::None;
     PollReady,               sym::Ready,               poll_ready_variant,         Target::Variant,        GenericRequirement::None;
@@ -294,8 +302,6 @@ language_item_table! {
     Context,                 sym::Context,             context,                    Target::Struct,         GenericRequirement::None;
     FuturePoll,              sym::poll,                future_poll_fn,             Target::Method(MethodKind::Trait { body: false }), GenericRequirement::None;
 
-    FromFrom,                sym::from,                from_fn,                    Target::Method(MethodKind::Trait { body: false }), GenericRequirement::None;
-
     OptionSome,              sym::Some,                option_some_variant,        Target::Variant,        GenericRequirement::None;
     OptionNone,              sym::None,                option_none_variant,        Target::Variant,        GenericRequirement::None;
 
diff --git a/compiler/rustc_hir/src/stable_hash_impls.rs b/compiler/rustc_hir/src/stable_hash_impls.rs
index 23423e8f3..85d0e02d0 100644
--- a/compiler/rustc_hir/src/stable_hash_impls.rs
+++ b/compiler/rustc_hir/src/stable_hash_impls.rs
@@ -100,13 +100,8 @@ impl<'tcx, HirCtx: crate::HashStableContext> HashStable<HirCtx> for OwnerNodes<'
         // `local_id_to_def_id` is also ignored because is dependent on the body, then just hashing
         // the body satisfies the condition of two nodes being different have different
         // `hash_stable` results.
-        let OwnerNodes {
-            hash_including_bodies,
-            hash_without_bodies: _,
-            nodes: _,
-            bodies: _,
-            local_id_to_def_id: _,
-        } = *self;
+        let OwnerNodes { hash_including_bodies, hash_without_bodies: _, nodes: _, bodies: _ } =
+            *self;
         hash_including_bodies.hash_stable(hcx, hasher);
     }
 }
diff --git a/compiler/rustc_hir/src/target.rs b/compiler/rustc_hir/src/target.rs
index 5917d5e34..961deac54 100644
--- a/compiler/rustc_hir/src/target.rs
+++ b/compiler/rustc_hir/src/target.rs
@@ -116,7 +116,7 @@ impl Target {
             DefKind::Union => Target::Union,
             DefKind::Trait => Target::Trait,
             DefKind::TraitAlias => Target::TraitAlias,
-            DefKind::Impl => Target::Impl,
+            DefKind::Impl { .. } => Target::Impl,
             _ => panic!("impossible case reached"),
         }
     }