Apply EarlyBidner only to TraitRef in ImplTraitHeader

Y-Nak · Y-Nak · commit f543c8d2bfc5 · 2024-03-05T20:19:05.000+01:00
diff --git a/compiler/rustc_hir_analysis/src/astconv/mod.rs b/compiler/rustc_hir_analysis/src/astconv/mod.rs
@@ -1612,10 +1612,11 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                         .any(|impl_def_id| {
                             let impl_header = tcx.impl_trait_header(impl_def_id);
                             impl_header.is_some_and(|header| {
-                                let header = header.instantiate(
+                                let trait_ref = header.trait_ref.instantiate(
                                     tcx,
                                     infcx.fresh_args_for_item(DUMMY_SP, impl_def_id),
                                 );
+
                                 let value = tcx.fold_regions(qself_ty, |_, _| tcx.lifetimes.re_erased);
                                 // FIXME: Don't bother dealing with non-lifetime binders here...
                                 if value.has_escaping_bound_vars() {
@@ -1624,7 +1625,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                                 infcx
                                     .can_eq(
                                         ty::ParamEnv::empty(),
-                                        header.trait_ref.self_ty(),
+                                        trait_ref.self_ty(),
                                         value,
                                     ) && header.polarity != ty::ImplPolarity::Negative
                             })
@@ -1677,9 +1678,9 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     .filter(|header| {
                         // Consider only accessible traits
                         tcx.visibility(trait_def_id).is_accessible_from(self.item_def_id(), tcx)
-                            && header.skip_binder().polarity != ty::ImplPolarity::Negative
+                            && header.polarity != ty::ImplPolarity::Negative
                     })
-                    .map(|header| header.instantiate_identity().trait_ref.self_ty())
+                    .map(|header| header.trait_ref.instantiate_identity().self_ty())
                     // We don't care about blanket impls.
                     .filter(|self_ty| !self_ty.has_non_region_param())
                     .map(|self_ty| tcx.erase_regions(self_ty).to_string())
diff --git a/compiler/rustc_hir_analysis/src/check/check.rs b/compiler/rustc_hir_analysis/src/check/check.rs
@@ -540,11 +540,7 @@ pub(crate) fn check_item_type(tcx: TyCtxt<'_>, def_id: LocalDefId) {
         }
         DefKind::Impl { of_trait } => {
             if of_trait && let Some(impl_trait_header) = tcx.impl_trait_header(def_id) {
-                check_impl_items_against_trait(
-                    tcx,
-                    def_id,
-                    impl_trait_header.instantiate_identity(),
-                );
+                check_impl_items_against_trait(tcx, def_id, impl_trait_header);
                 check_on_unimplemented(tcx, def_id);
             }
         }
@@ -735,10 +731,11 @@ fn check_impl_items_against_trait<'tcx>(
     impl_id: LocalDefId,
     impl_trait_header: ty::ImplTraitHeader<'tcx>,
 ) {
+    let trait_ref = impl_trait_header.trait_ref.instantiate_identity();
     // If the trait reference itself is erroneous (so the compilation is going
     // to fail), skip checking the items here -- the `impl_item` table in `tcx`
     // isn't populated for such impls.
-    if impl_trait_header.references_error() {
+    if trait_ref.references_error() {
         return;
     }
 
@@ -762,7 +759,7 @@ fn check_impl_items_against_trait<'tcx>(
         }
     }
 
-    let trait_def = tcx.trait_def(impl_trait_header.trait_ref.def_id);
+    let trait_def = tcx.trait_def(trait_ref.def_id);
 
     for &impl_item in impl_item_refs {
         let ty_impl_item = tcx.associated_item(impl_item);
@@ -781,10 +778,10 @@ fn check_impl_items_against_trait<'tcx>(
                 ));
             }
             ty::AssocKind::Fn => {
-                compare_impl_method(tcx, ty_impl_item, ty_trait_item, impl_trait_header.trait_ref);
+                compare_impl_method(tcx, ty_impl_item, ty_trait_item, trait_ref);
             }
             ty::AssocKind::Type => {
-                compare_impl_ty(tcx, ty_impl_item, ty_trait_item, impl_trait_header.trait_ref);
+                compare_impl_ty(tcx, ty_impl_item, ty_trait_item, trait_ref);
             }
         }
 
@@ -804,7 +801,7 @@ fn check_impl_items_against_trait<'tcx>(
         let mut must_implement_one_of: Option<&[Ident]> =
             trait_def.must_implement_one_of.as_deref();
 
-        for &trait_item_id in tcx.associated_item_def_ids(impl_trait_header.trait_ref.def_id) {
+        for &trait_item_id in tcx.associated_item_def_ids(trait_ref.def_id) {
             let leaf_def = ancestors.leaf_def(tcx, trait_item_id);
 
             let is_implemented = leaf_def
@@ -882,7 +879,7 @@ fn check_impl_items_against_trait<'tcx>(
 
         if let Some(missing_items) = must_implement_one_of {
             let attr_span = tcx
-                .get_attr(impl_trait_header.trait_ref.def_id, sym::rustc_must_implement_one_of)
+                .get_attr(trait_ref.def_id, sym::rustc_must_implement_one_of)
                 .map(|attr| attr.span);
 
             missing_items_must_implement_one_of_err(
diff --git a/compiler/rustc_hir_analysis/src/check/wfcheck.rs b/compiler/rustc_hir_analysis/src/check/wfcheck.rs
@@ -247,7 +247,7 @@ fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) -> Result<()
         hir::ItemKind::Impl(impl_) => {
             let header = tcx.impl_trait_header(def_id);
             let is_auto = header
-                .is_some_and(|header| tcx.trait_is_auto(header.skip_binder().trait_ref.def_id));
+                .is_some_and(|header| tcx.trait_is_auto(header.trait_ref.skip_binder().def_id));
             let mut res = Ok(());
             if let (hir::Defaultness::Default { .. }, true) = (impl_.defaultness, is_auto) {
                 let sp = impl_.of_trait.as_ref().map_or(item.span, |t| t.path.span);
@@ -259,7 +259,7 @@ fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) -> Result<()
                     .emit());
             }
             // We match on both `ty::ImplPolarity` and `ast::ImplPolarity` just to get the `!` span.
-            match header.map(|h| h.skip_binder().polarity) {
+            match header.map(|h| h.polarity) {
                 // `None` means this is an inherent impl
                 Some(ty::ImplPolarity::Positive) | None => {
                     res = res.and(check_impl(tcx, item, impl_.self_ty, &impl_.of_trait));
diff --git a/compiler/rustc_hir_analysis/src/coherence/builtin.rs b/compiler/rustc_hir_analysis/src/coherence/builtin.rs
@@ -25,14 +25,14 @@ use rustc_trait_selection::traits::ObligationCtxt;
 use rustc_trait_selection::traits::{self, ObligationCause};
 use std::collections::BTreeMap;
 
-pub fn check_trait<'tcx>(
+pub(super) fn check_trait<'tcx>(
     tcx: TyCtxt<'tcx>,
     trait_def_id: DefId,
     impl_def_id: LocalDefId,
     impl_header: ty::ImplTraitHeader<'tcx>,
 ) -> Result<(), ErrorGuaranteed> {
     let lang_items = tcx.lang_items();
-    let checker = Checker { tcx, trait_def_id, impl_def_id, impl_header };
+    let checker = Checker::new(tcx, trait_def_id, impl_def_id, impl_header);
     let mut res = checker.check(lang_items.drop_trait(), visit_implementation_of_drop);
     res = res.and(checker.check(lang_items.copy_trait(), visit_implementation_of_copy));
     res = res.and(
@@ -52,9 +52,19 @@ struct Checker<'tcx> {
     trait_def_id: DefId,
     impl_def_id: LocalDefId,
     impl_header: ty::ImplTraitHeader<'tcx>,
+    trait_ref: ty::TraitRef<'tcx>,
 }
 
 impl<'tcx> Checker<'tcx> {
+    fn new(
+        tcx: TyCtxt<'tcx>,
+        trait_def_id: DefId,
+        impl_def_id: LocalDefId,
+        impl_header: ty::ImplTraitHeader<'tcx>,
+    ) -> Self {
+        let trait_ref = impl_header.trait_ref.instantiate_identity();
+        Self { tcx, trait_def_id, impl_def_id, impl_header, trait_ref }
+    }
     fn check(
         &self,
         trait_def_id: Option<DefId>,
@@ -66,10 +76,9 @@ impl<'tcx> Checker<'tcx> {
 
 fn visit_implementation_of_drop(checker: &Checker<'_>) -> Result<(), ErrorGuaranteed> {
     let tcx = checker.tcx;
-    let header = checker.impl_header;
     let impl_did = checker.impl_def_id;
     // Destructors only work on local ADT types.
-    match header.trait_ref.self_ty().kind() {
+    match checker.trait_ref.self_ty().kind() {
         ty::Adt(def, _) if def.did().is_local() => return Ok(()),
         ty::Error(_) => return Ok(()),
         _ => {}
@@ -86,7 +95,7 @@ fn visit_implementation_of_copy(checker: &Checker<'_>) -> Result<(), ErrorGuaran
     let impl_did = checker.impl_def_id;
     debug!("visit_implementation_of_copy: impl_did={:?}", impl_did);
 
-    let self_type = impl_header.trait_ref.self_ty();
+    let self_type = checker.trait_ref.self_ty();
     debug!("visit_implementation_of_copy: self_type={:?} (bound)", self_type);
 
     let param_env = tcx.param_env(impl_did);
@@ -120,7 +129,7 @@ fn visit_implementation_of_const_param_ty(checker: &Checker<'_>) -> Result<(), E
     let tcx = checker.tcx;
     let header = checker.impl_header;
     let impl_did = checker.impl_def_id;
-    let self_type = header.trait_ref.self_ty();
+    let self_type = checker.trait_ref.self_ty();
     assert!(!self_type.has_escaping_bound_vars());
 
     let param_env = tcx.param_env(impl_did);
@@ -157,9 +166,8 @@ fn visit_implementation_of_coerce_unsized(checker: &Checker<'_>) -> Result<(), E
 
 fn visit_implementation_of_dispatch_from_dyn(checker: &Checker<'_>) -> Result<(), ErrorGuaranteed> {
     let tcx = checker.tcx;
-    let header = checker.impl_header;
     let impl_did = checker.impl_def_id;
-    let trait_ref = header.trait_ref;
+    let trait_ref = checker.trait_ref;
     debug!("visit_implementation_of_dispatch_from_dyn: impl_did={:?}", impl_did);
 
     let span = tcx.def_span(impl_did);
diff --git a/compiler/rustc_hir_analysis/src/coherence/mod.rs b/compiler/rustc_hir_analysis/src/coherence/mod.rs
@@ -134,11 +134,12 @@ fn coherent_trait(tcx: TyCtxt<'_>, def_id: DefId) -> Result<(), ErrorGuaranteed>
     let mut res = tcx.ensure().specialization_graph_of(def_id);
 
     for &impl_def_id in impls {
-        let trait_header = tcx.impl_trait_header(impl_def_id).unwrap().instantiate_identity();
-        let trait_def = tcx.trait_def(trait_header.trait_ref.def_id);
+        let trait_header = tcx.impl_trait_header(impl_def_id).unwrap();
+        let trait_ref = trait_header.trait_ref.instantiate_identity();
+        let trait_def = tcx.trait_def(trait_ref.def_id);
 
-        res = res.and(check_impl(tcx, impl_def_id, trait_header.trait_ref, trait_def));
-        res = res.and(check_object_overlap(tcx, impl_def_id, trait_header.trait_ref));
+        res = res.and(check_impl(tcx, impl_def_id, trait_ref, trait_def));
+        res = res.and(check_object_overlap(tcx, impl_def_id, trait_ref));
 
         res = res.and(unsafety::check_item(tcx, impl_def_id, trait_header, trait_def));
         res = res.and(tcx.ensure().orphan_check_impl(impl_def_id));
diff --git a/compiler/rustc_hir_analysis/src/coherence/unsafety.rs b/compiler/rustc_hir_analysis/src/coherence/unsafety.rs
@@ -13,9 +13,10 @@ pub(super) fn check_item(
     trait_header: ImplTraitHeader<'_>,
     trait_def: &TraitDef,
 ) -> Result<(), ErrorGuaranteed> {
-    let trait_ref = trait_header.trait_ref;
     let unsafe_attr =
         tcx.generics_of(def_id).params.iter().find(|p| p.pure_wrt_drop).map(|_| "may_dangle");
+    let trait_ref = trait_header.trait_ref.instantiate_identity();
+
     match (trait_def.unsafety, unsafe_attr, trait_header.unsafety, trait_header.polarity) {
         (Unsafety::Normal, None, Unsafety::Unsafe, Positive | Reservation) => {
             let span = tcx.def_span(def_id);
diff --git a/compiler/rustc_hir_analysis/src/collect.rs b/compiler/rustc_hir_analysis/src/collect.rs
@@ -1514,10 +1514,7 @@ fn suggest_impl_trait<'tcx>(
     None
 }
 
-fn impl_trait_header(
-    tcx: TyCtxt<'_>,
-    def_id: LocalDefId,
-) -> Option<ty::EarlyBinder<ty::ImplTraitHeader<'_>>> {
+fn impl_trait_header(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option<ty::ImplTraitHeader<'_>> {
     let icx = ItemCtxt::new(tcx, def_id);
     let item = tcx.hir().expect_item(def_id);
     let impl_ = item.expect_impl();
@@ -1553,11 +1550,11 @@ fn impl_trait_header(
             } else {
                 icx.astconv().instantiate_mono_trait_ref(ast_trait_ref, selfty)
             };
-            ty::EarlyBinder::bind(ty::ImplTraitHeader {
-                trait_ref,
+            ty::ImplTraitHeader {
+                trait_ref: ty::EarlyBinder::bind(trait_ref),
                 unsafety: impl_.unsafety,
                 polarity: polarity_of_impl(tcx, def_id,  impl_, item.span)
-            })
+            }
         })
 }
 
diff --git a/compiler/rustc_hir_typeck/src/method/suggest.rs b/compiler/rustc_hir_typeck/src/method/suggest.rs
@@ -3368,11 +3368,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 "inherent impls can't be candidates, only trait impls can be",
                             )
                         })
-                        .filter(|header| {
-                            header.skip_binder().polarity == ty::ImplPolarity::Negative
-                        })
+                        .filter(|header| header.polarity == ty::ImplPolarity::Negative)
                         .any(|header| {
-                            let imp = header.instantiate_identity().trait_ref;
+                            let imp = header.trait_ref.instantiate_identity();
                             let imp_simp =
                                 simplify_type(self.tcx, imp.self_ty(), TreatParams::ForLookup);
                             imp_simp.is_some_and(|s| s == simp_rcvr_ty)
diff --git a/compiler/rustc_metadata/src/rmeta/encoder.rs b/compiler/rustc_metadata/src/rmeta/encoder.rs
@@ -1981,7 +1981,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
 
             if of_trait && let Some(header) = tcx.impl_trait_header(def_id) {
                 record!(self.tables.impl_trait_header[def_id] <- header);
-                let trait_ref = header.map_bound(|h| h.trait_ref);
+                let trait_ref = header.trait_ref;
 
                 let trait_ref = trait_ref.instantiate_identity();
                 let simplified_self_ty = fast_reject::simplify_type(
diff --git a/compiler/rustc_metadata/src/rmeta/mod.rs b/compiler/rustc_metadata/src/rmeta/mod.rs
@@ -423,7 +423,7 @@ define_tables! {
     variances_of: Table<DefIndex, LazyArray<ty::Variance>>,
     fn_sig: Table<DefIndex, LazyValue<ty::EarlyBinder<ty::PolyFnSig<'static>>>>,
     codegen_fn_attrs: Table<DefIndex, LazyValue<CodegenFnAttrs>>,
-    impl_trait_header: Table<DefIndex, LazyValue<ty::EarlyBinder<ty::ImplTraitHeader<'static>>>>,
+    impl_trait_header: Table<DefIndex, LazyValue<ty::ImplTraitHeader<'static>>>,
     const_param_default: Table<DefIndex, LazyValue<ty::EarlyBinder<rustc_middle::ty::Const<'static>>>>,
     object_lifetime_default: Table<DefIndex, LazyValue<ObjectLifetimeDefault>>,
     optimized_mir: Table<DefIndex, LazyValue<mir::Body<'static>>>,
diff --git a/compiler/rustc_middle/src/query/erase.rs b/compiler/rustc_middle/src/query/erase.rs
@@ -177,8 +177,8 @@ impl EraseType for Option<mir::DestructuredConstant<'_>> {
     type Result = [u8; size_of::<Option<mir::DestructuredConstant<'static>>>()];
 }
 
-impl EraseType for Option<ty::EarlyBinder<ty::ImplTraitHeader<'_>>> {
-    type Result = [u8; size_of::<Option<ty::EarlyBinder<ty::ImplTraitHeader<'static>>>>()];
+impl EraseType for Option<ty::ImplTraitHeader<'_>> {
+    type Result = [u8; size_of::<Option<ty::ImplTraitHeader<'static>>>()];
 }
 
 impl EraseType for Option<ty::EarlyBinder<Ty<'_>>> {
diff --git a/compiler/rustc_middle/src/query/mod.rs b/compiler/rustc_middle/src/query/mod.rs
@@ -849,7 +849,7 @@ rustc_queries! {
 
     /// Given an `impl_id`, return the trait it implements along with some header information.
     /// Return `None` if this is an inherent impl.
-    query impl_trait_header(impl_id: DefId) -> Option<ty::EarlyBinder<ty::ImplTraitHeader<'tcx>>> {
+    query impl_trait_header(impl_id: DefId) -> Option<ty::ImplTraitHeader<'tcx>> {
         desc { |tcx| "computing trait implemented by `{}`", tcx.def_path_str(impl_id) }
         cache_on_disk_if { impl_id.is_local() }
         separate_provide_extern
diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
@@ -2310,12 +2310,11 @@ impl<'tcx> TyCtxt<'tcx> {
         self,
         def_id: impl IntoQueryParam<DefId>,
     ) -> Option<ty::EarlyBinder<ty::TraitRef<'tcx>>> {
-        Some(self.impl_trait_header(def_id)?.map_bound(|h| h.trait_ref))
+        Some(self.impl_trait_header(def_id)?.trait_ref)
     }
 
     pub fn impl_polarity(self, def_id: impl IntoQueryParam<DefId>) -> ty::ImplPolarity {
-        self.impl_trait_header(def_id)
-            .map_or(ty::ImplPolarity::Positive, |h| h.skip_binder().polarity)
+        self.impl_trait_header(def_id).map_or(ty::ImplPolarity::Positive, |h| h.polarity)
     }
 }
 
diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs
@@ -251,9 +251,9 @@ pub struct ImplHeader<'tcx> {
     pub predicates: Vec<Predicate<'tcx>>,
 }
 
-#[derive(Copy, Clone, Debug, TypeFoldable, TypeVisitable, TyEncodable, TyDecodable, HashStable)]
+#[derive(Copy, Clone, Debug, TyEncodable, TyDecodable, HashStable)]
 pub struct ImplTraitHeader<'tcx> {
-    pub trait_ref: ty::TraitRef<'tcx>,
+    pub trait_ref: ty::EarlyBinder<ty::TraitRef<'tcx>>,
     pub polarity: ImplPolarity,
     pub unsafety: hir::Unsafety,
 }
@@ -1625,12 +1625,15 @@ impl<'tcx> TyCtxt<'tcx> {
         def_id1: DefId,
         def_id2: DefId,
     ) -> Option<ImplOverlapKind> {
-        let impl1 = self.impl_trait_header(def_id1).unwrap().instantiate_identity();
-        let impl2 = self.impl_trait_header(def_id2).unwrap().instantiate_identity();
+        let impl1 = self.impl_trait_header(def_id1).unwrap();
+        let impl2 = self.impl_trait_header(def_id2).unwrap();
+
+        let trait_ref1 = impl1.trait_ref.instantiate_identity();
+        let trait_ref2 = impl2.trait_ref.instantiate_identity();
 
         // If either trait impl references an error, they're allowed to overlap,
         // as one of them essentially doesn't exist.
-        if impl1.references_error() || impl2.references_error() {
+        if trait_ref1.references_error() || trait_ref2.references_error() {
             return Some(ImplOverlapKind::Permitted { marker: false });
         }
 
@@ -1651,7 +1654,7 @@ impl<'tcx> TyCtxt<'tcx> {
         let is_marker_overlap = {
             let is_marker_impl =
                 |trait_ref: TraitRef<'_>| -> bool { self.trait_def(trait_ref.def_id).is_marker };
-            is_marker_impl(impl1.trait_ref) && is_marker_impl(impl2.trait_ref)
+            is_marker_impl(trait_ref1) && is_marker_impl(trait_ref2)
         };
 
         if is_marker_overlap {
diff --git a/compiler/rustc_monomorphize/src/collector.rs b/compiler/rustc_monomorphize/src/collector.rs
@@ -1361,7 +1361,7 @@ fn create_mono_items_for_default_impls<'tcx>(
         return;
     };
 
-    if matches!(impl_.skip_binder().polarity, ty::ImplPolarity::Negative) {
+    if matches!(impl_.polarity, ty::ImplPolarity::Negative) {
         return;
     }
 
@@ -1385,7 +1385,7 @@ fn create_mono_items_for_default_impls<'tcx>(
         }
     };
     let impl_args = GenericArgs::for_item(tcx, item.owner_id.to_def_id(), only_region_params);
-    let trait_ref = impl_.instantiate(tcx, impl_args).trait_ref;
+    let trait_ref = impl_.trait_ref.instantiate(tcx, impl_args);
 
     // Unlike 'lazy' monomorphization that begins by collecting items transitively
     // called by `main` or other global items, when eagerly monomorphizing impl
diff --git a/compiler/rustc_trait_selection/src/solve/normalizes_to/mod.rs b/compiler/rustc_trait_selection/src/solve/normalizes_to/mod.rs
diff --git a/compiler/rustc_trait_selection/src/solve/trait_goals.rs b/compiler/rustc_trait_selection/src/solve/trait_goals.rs
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs
diff --git a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs
diff --git a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs
diff --git a/compiler/rustc_ty_utils/src/ty.rs b/compiler/rustc_ty_utils/src/ty.rs

Original file line number	Diff line number	Diff line change
`@@ -540,11 +540,7 @@ pub(crate) fn check_item_type(tcx: TyCtxt<'_>, def_id: LocalDefId) {`
`540`	`540`	`}`
`541`	`541`	`DefKind::Impl { of_trait } => {`
`542`	`542`	`if of_trait && let Some(impl_trait_header) = tcx.impl_trait_header(def_id) {`
`543`		`- check_impl_items_against_trait(`
`544`		`- tcx,`
`545`		`- def_id,`
`546`		`- impl_trait_header.instantiate_identity(),`
`547`		`- );`
	`543`	`+ check_impl_items_against_trait(tcx, def_id, impl_trait_header);`
`548`	`544`	`check_on_unimplemented(tcx, def_id);`
`549`	`545`	`}`
`550`	`546`	`}`
`@@ -735,10 +731,11 @@ fn check_impl_items_against_trait<'tcx>(`
`735`	`731`	`impl_id: LocalDefId,`
`736`	`732`	`impl_trait_header: ty::ImplTraitHeader<'tcx>,`
`737`	`733`	`) {`
	`734`	`+ let trait_ref = impl_trait_header.trait_ref.instantiate_identity();`
`738`	`735`	`// If the trait reference itself is erroneous (so the compilation is going`
`739`	`736`	// to fail), skip checking the items here -- the `impl_item` table in `tcx`
`740`	`737`	`// isn't populated for such impls.`
`741`		`- if impl_trait_header.references_error() {`
	`738`	`+ if trait_ref.references_error() {`
`742`	`739`	`return;`
`743`	`740`	`}`
`744`	`741`
`@@ -762,7 +759,7 @@ fn check_impl_items_against_trait<'tcx>(`
`762`	`759`	`}`
`763`	`760`	`}`
`764`	`761`
`765`		`- let trait_def = tcx.trait_def(impl_trait_header.trait_ref.def_id);`
	`762`	`+ let trait_def = tcx.trait_def(trait_ref.def_id);`
`766`	`763`
`767`	`764`	`for &impl_item in impl_item_refs {`
`768`	`765`	`let ty_impl_item = tcx.associated_item(impl_item);`
`@@ -781,10 +778,10 @@ fn check_impl_items_against_trait<'tcx>(`
`781`	`778`	`));`
`782`	`779`	`}`
`783`	`780`	`ty::AssocKind::Fn => {`
`784`		`- compare_impl_method(tcx, ty_impl_item, ty_trait_item, impl_trait_header.trait_ref);`
	`781`	`+ compare_impl_method(tcx, ty_impl_item, ty_trait_item, trait_ref);`
`785`	`782`	`}`
`786`	`783`	`ty::AssocKind::Type => {`
`787`		`- compare_impl_ty(tcx, ty_impl_item, ty_trait_item, impl_trait_header.trait_ref);`
	`784`	`+ compare_impl_ty(tcx, ty_impl_item, ty_trait_item, trait_ref);`
`788`	`785`	`}`
`789`	`786`	`}`
`790`	`787`
`@@ -804,7 +801,7 @@ fn check_impl_items_against_trait<'tcx>(`
`804`	`801`	`let mut must_implement_one_of: Option<&[Ident]> =`
`805`	`802`	`trait_def.must_implement_one_of.as_deref();`
`806`	`803`
`807`		`- for &trait_item_id in tcx.associated_item_def_ids(impl_trait_header.trait_ref.def_id) {`
	`804`	`+ for &trait_item_id in tcx.associated_item_def_ids(trait_ref.def_id) {`
`808`	`805`	`let leaf_def = ancestors.leaf_def(tcx, trait_item_id);`
`809`	`806`
`810`	`807`	`let is_implemented = leaf_def`
`@@ -882,7 +879,7 @@ fn check_impl_items_against_trait<'tcx>(`
`882`	`879`
`883`	`880`	`if let Some(missing_items) = must_implement_one_of {`
`884`	`881`	`let attr_span = tcx`
`885`		`- .get_attr(impl_trait_header.trait_ref.def_id, sym::rustc_must_implement_one_of)`
	`882`	`+ .get_attr(trait_ref.def_id, sym::rustc_must_implement_one_of)`
`886`	`883`	`.map(\|attr\| attr.span);`
`887`	`884`
`888`	`885`	`missing_items_must_implement_one_of_err(`