Do not consider child bound assumptions for rigid alias

compiler/rustc_hir_analysis/src/check/mod.rs

@@ -457,7 +457,7 @@ fn fn_sig_suggestion<'tcx>(
 
     let asyncness = if tcx.asyncness(assoc.def_id).is_async() {
         output = if let ty::Alias(_, alias_ty) = *output.kind() {
-            tcx.explicit_item_super_predicates(alias_ty.def_id)
+            tcx.explicit_item_self_bounds(alias_ty.def_id)
                 .iter_instantiated_copied(tcx, alias_ty.args)
                 .find_map(|(bound, _)| {
                     bound.as_projection_clause()?.no_bound_vars()?.term.as_type()

compiler/rustc_hir_analysis/src/collect.rs

@@ -65,9 +65,9 @@ pub fn provide(providers: &mut Providers) {
         type_alias_is_lazy: type_of::type_alias_is_lazy,
         item_bounds: item_bounds::item_bounds,
         explicit_item_bounds: item_bounds::explicit_item_bounds,
-        item_super_predicates: item_bounds::item_super_predicates,
-        explicit_item_super_predicates: item_bounds::explicit_item_super_predicates,
-        item_non_self_assumptions: item_bounds::item_non_self_assumptions,
+        item_self_bounds: item_bounds::item_self_bounds,
+        explicit_item_self_bounds: item_bounds::explicit_item_self_bounds,
+        item_non_self_bounds: item_bounds::item_non_self_bounds,
         impl_super_outlives: item_bounds::impl_super_outlives,
         generics_of: generics_of::generics_of,
         predicates_of: predicates_of::predicates_of,
@@ -328,9 +328,9 @@ impl<'tcx> Visitor<'tcx> for CollectItemTypesVisitor<'tcx> {
         self.tcx.ensure().generics_of(def_id);
         self.tcx.ensure().predicates_of(def_id);
         self.tcx.ensure().explicit_item_bounds(def_id);
-        self.tcx.ensure().explicit_item_super_predicates(def_id);
+        self.tcx.ensure().explicit_item_self_bounds(def_id);
         self.tcx.ensure().item_bounds(def_id);
-        self.tcx.ensure().item_super_predicates(def_id);
+        self.tcx.ensure().item_self_bounds(def_id);
         if self.tcx.is_conditionally_const(def_id) {
             self.tcx.ensure().explicit_implied_const_bounds(def_id);
             self.tcx.ensure().const_conditions(def_id);
@@ -822,7 +822,7 @@ fn lower_trait_item(tcx: TyCtxt<'_>, trait_item_id: hir::TraitItemId) {
 
         hir::TraitItemKind::Type(_, Some(_)) => {
             tcx.ensure().item_bounds(def_id);
-            tcx.ensure().item_super_predicates(def_id);
+            tcx.ensure().item_self_bounds(def_id);
             tcx.ensure().type_of(def_id);
             // Account for `type T = _;`.
             let mut visitor = HirPlaceholderCollector::default();
@@ -839,7 +839,7 @@ fn lower_trait_item(tcx: TyCtxt<'_>, trait_item_id: hir::TraitItemId) {
 
         hir::TraitItemKind::Type(_, None) => {
             tcx.ensure().item_bounds(def_id);
-            tcx.ensure().item_super_predicates(def_id);
+            tcx.ensure().item_self_bounds(def_id);
             // #74612: Visit and try to find bad placeholders
             // even if there is no concrete type.
             let mut visitor = HirPlaceholderCollector::default();

compiler/rustc_hir_analysis/src/collect/item_bounds.rs

@@ -350,7 +350,7 @@ pub(super) fn explicit_item_bounds(
     explicit_item_bounds_with_filter(tcx, def_id, PredicateFilter::All)
 }
 
-pub(super) fn explicit_item_super_predicates(
+pub(super) fn explicit_item_self_bounds(
     tcx: TyCtxt<'_>,
     def_id: LocalDefId,
 ) -> ty::EarlyBinder<'_, &'_ [(ty::Clause<'_>, Span)]> {
@@ -434,11 +434,11 @@ pub(super) fn item_bounds(tcx: TyCtxt<'_>, def_id: DefId) -> ty::EarlyBinder<'_,
     })
 }
 
-pub(super) fn item_super_predicates(
+pub(super) fn item_self_bounds(
     tcx: TyCtxt<'_>,
     def_id: DefId,
 ) -> ty::EarlyBinder<'_, ty::Clauses<'_>> {
-    tcx.explicit_item_super_predicates(def_id).map_bound(|bounds| {
+    tcx.explicit_item_self_bounds(def_id).map_bound(|bounds| {
         tcx.mk_clauses_from_iter(
             util::elaborate(tcx, bounds.iter().map(|&(bound, _span)| bound)).filter_only_self(),
         )
@@ -447,13 +447,12 @@ pub(super) fn item_super_predicates(
 
 /// This exists as an optimization to compute only the item bounds of the item
 /// that are not `Self` bounds.
-pub(super) fn item_non_self_assumptions(
+pub(super) fn item_non_self_bounds(
     tcx: TyCtxt<'_>,
     def_id: DefId,
 ) -> ty::EarlyBinder<'_, ty::Clauses<'_>> {
     let all_bounds: FxIndexSet<_> = tcx.item_bounds(def_id).skip_binder().iter().collect();
-    let own_bounds: FxIndexSet<_> =
-        tcx.item_super_predicates(def_id).skip_binder().iter().collect();
+    let own_bounds: FxIndexSet<_> = tcx.item_self_bounds(def_id).skip_binder().iter().collect();
     if all_bounds.len() == own_bounds.len() {
         ty::EarlyBinder::bind(ty::ListWithCachedTypeInfo::empty())
     } else {

compiler/rustc_hir_typeck/src/closure.rs

@@ -308,7 +308,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     expected_ty,
                     closure_kind,
                     self.tcx
-                        .explicit_item_super_predicates(def_id)
+                        .explicit_item_self_bounds(def_id)
                         .iter_instantiated_copied(self.tcx, args)
                         .map(|(c, s)| (c.as_predicate(), s)),
                 ),
@@ -981,7 +981,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             }
             ty::Alias(ty::Opaque, ty::AliasTy { def_id, args, .. }) => self
                 .tcx
-                .explicit_item_super_predicates(def_id)
+                .explicit_item_self_bounds(def_id)
                 .iter_instantiated_copied(self.tcx, args)
                 .find_map(|(p, s)| get_future_output(p.as_predicate(), s))?,
             ty::Error(_) => return Some(ret_ty),

compiler/rustc_hir_typeck/src/coercion.rs

@@ -1847,30 +1847,26 @@ impl<'tcx, 'exprs, E: AsCoercionSite> CoerceMany<'tcx, 'exprs, E> {
             fcx.probe(|_| {
                 let ocx = ObligationCtxt::new(fcx);
                 ocx.register_obligations(
-                    fcx.tcx.item_super_predicates(rpit_def_id).iter_identity().filter_map(
-                        |clause| {
-                            let predicate = clause
-                                .kind()
-                                .map_bound(|clause| match clause {
-                                    ty::ClauseKind::Trait(trait_pred) => Some(
-                                        ty::ClauseKind::Trait(trait_pred.with_self_ty(fcx.tcx, ty)),
-                                    ),
-                                    ty::ClauseKind::Projection(proj_pred) => {
-                                        Some(ty::ClauseKind::Projection(
-                                            proj_pred.with_self_ty(fcx.tcx, ty),
-                                        ))
-                                    }
-                                    _ => None,
-                                })
-                                .transpose()?;
-                            Some(Obligation::new(
-                                fcx.tcx,
-                                ObligationCause::dummy(),
-                                fcx.param_env,
-                                predicate,
-                            ))
-                        },
-                    ),
+                    fcx.tcx.item_self_bounds(rpit_def_id).iter_identity().filter_map(|clause| {
+                        let predicate = clause
+                            .kind()
+                            .map_bound(|clause| match clause {
+                                ty::ClauseKind::Trait(trait_pred) => Some(ty::ClauseKind::Trait(
+                                    trait_pred.with_self_ty(fcx.tcx, ty),
+                                )),
+                                ty::ClauseKind::Projection(proj_pred) => Some(
+                                    ty::ClauseKind::Projection(proj_pred.with_self_ty(fcx.tcx, ty)),
+                                ),
+                                _ => None,
+                            })
+                            .transpose()?;
+                        Some(Obligation::new(
+                            fcx.tcx,
+                            ObligationCause::dummy(),
+                            fcx.param_env,
+                            predicate,
+                        ))
+                    }),
                 );
                 ocx.select_where_possible().is_empty()
             })

compiler/rustc_infer/src/infer/outlives/verify.rs

@@ -281,7 +281,7 @@ impl<'cx, 'tcx> VerifyBoundCx<'cx, 'tcx> {
         alias_ty: ty::AliasTy<'tcx>,
     ) -> impl Iterator<Item = ty::Region<'tcx>> {
         let tcx = self.tcx;
-        let bounds = tcx.item_super_predicates(alias_ty.def_id);
+        let bounds = tcx.item_self_bounds(alias_ty.def_id);
         trace!("{:#?}", bounds.skip_binder());
         bounds
             .iter_instantiated(tcx, alias_ty.args)

compiler/rustc_lint/src/unused.rs

@@ -289,25 +289,22 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults {
                 }
                 ty::Adt(def, _) => is_def_must_use(cx, def.did(), span),
                 ty::Alias(ty::Opaque | ty::Projection, ty::AliasTy { def_id: def, .. }) => {
-                    elaborate(
-                        cx.tcx,
-                        cx.tcx.explicit_item_super_predicates(def).iter_identity_copied(),
-                    )
-                    // We only care about self bounds for the impl-trait
-                    .filter_only_self()
-                    .find_map(|(pred, _span)| {
-                        // We only look at the `DefId`, so it is safe to skip the binder here.
-                        if let ty::ClauseKind::Trait(ref poly_trait_predicate) =
-                            pred.kind().skip_binder()
-                        {
-                            let def_id = poly_trait_predicate.trait_ref.def_id;
-
-                            is_def_must_use(cx, def_id, span)
-                        } else {
-                            None
-                        }
-                    })
-                    .map(|inner| MustUsePath::Opaque(Box::new(inner)))
+                    elaborate(cx.tcx, cx.tcx.explicit_item_self_bounds(def).iter_identity_copied())
+                        // We only care about self bounds for the impl-trait
+                        .filter_only_self()
+                        .find_map(|(pred, _span)| {
+                            // We only look at the `DefId`, so it is safe to skip the binder here.
+                            if let ty::ClauseKind::Trait(ref poly_trait_predicate) =
+                                pred.kind().skip_binder()
+                            {
+                                let def_id = poly_trait_predicate.trait_ref.def_id;
+
+                                is_def_must_use(cx, def_id, span)
+                            } else {
+                                None
+                            }
+                        })
+                        .map(|inner| MustUsePath::Opaque(Box::new(inner)))
                 }
                 ty::Dynamic(binders, _, _) => binders.iter().find_map(|predicate| {
                     if let ty::ExistentialPredicate::Trait(ref trait_ref) = predicate.skip_binder()

compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs

@@ -241,7 +241,7 @@ impl IntoArgs for (CrateNum, SimplifiedType) {
 
 provide! { tcx, def_id, other, cdata,
     explicit_item_bounds => { table_defaulted_array }
-    explicit_item_super_predicates => { table_defaulted_array }
+    explicit_item_self_bounds => { table_defaulted_array }
     explicit_predicates_of => { table }
     generics_of => { table }
     inferred_outlives_of => { table_defaulted_array }

compiler/rustc_metadata/src/rmeta/encoder.rs

@@ -1554,7 +1554,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             }
             if let DefKind::OpaqueTy = def_kind {
                 self.encode_explicit_item_bounds(def_id);
-                self.encode_explicit_item_super_predicates(def_id);
+                self.encode_explicit_item_self_bounds(def_id);
                 record!(self.tables.opaque_ty_origin[def_id] <- self.tcx.opaque_ty_origin(def_id));
                 self.encode_precise_capturing_args(def_id);
                 if tcx.is_conditionally_const(def_id) {
@@ -1667,10 +1667,10 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
         record_defaulted_array!(self.tables.explicit_item_bounds[def_id] <- bounds);
     }
 
-    fn encode_explicit_item_super_predicates(&mut self, def_id: DefId) {
-        debug!("EncodeContext::encode_explicit_item_super_predicates({:?})", def_id);
-        let bounds = self.tcx.explicit_item_super_predicates(def_id).skip_binder();
-        record_defaulted_array!(self.tables.explicit_item_super_predicates[def_id] <- bounds);
+    fn encode_explicit_item_self_bounds(&mut self, def_id: DefId) {
+        debug!("EncodeContext::encode_explicit_item_self_bounds({:?})", def_id);
+        let bounds = self.tcx.explicit_item_self_bounds(def_id).skip_binder();
+        record_defaulted_array!(self.tables.explicit_item_self_bounds[def_id] <- bounds);
     }
 
     #[instrument(level = "debug", skip(self))]
@@ -1685,7 +1685,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             AssocItemContainer::Trait => {
                 if let ty::AssocKind::Type = item.kind {
                     self.encode_explicit_item_bounds(def_id);
-                    self.encode_explicit_item_super_predicates(def_id);
+                    self.encode_explicit_item_self_bounds(def_id);
                     if tcx.is_conditionally_const(def_id) {
                         record_defaulted_array!(self.tables.explicit_implied_const_bounds[def_id]
                             <- self.tcx.explicit_implied_const_bounds(def_id).skip_binder());

compiler/rustc_metadata/src/rmeta/mod.rs

@@ -386,7 +386,7 @@ define_tables! {
     // corresponding DefPathHash.
     def_path_hashes: Table<DefIndex, u64>,
     explicit_item_bounds: Table<DefIndex, LazyArray<(ty::Clause<'static>, Span)>>,
-    explicit_item_super_predicates: Table<DefIndex, LazyArray<(ty::Clause<'static>, Span)>>,
+    explicit_item_self_bounds: Table<DefIndex, LazyArray<(ty::Clause<'static>, Span)>>,
     inferred_outlives_of: Table<DefIndex, LazyArray<(ty::Clause<'static>, Span)>>,
     explicit_super_predicates_of: Table<DefIndex, LazyArray<(ty::Clause<'static>, Span)>>,
     explicit_implied_predicates_of: Table<DefIndex, LazyArray<(ty::Clause<'static>, Span)>>,

compiler/rustc_middle/src/query/mod.rs

@@ -393,7 +393,7 @@ rustc_queries! {
     /// like closure signature deduction.
     ///
     /// [explicit item bounds]: Self::explicit_item_bounds
-    query explicit_item_super_predicates(key: DefId) -> ty::EarlyBinder<'tcx, &'tcx [(ty::Clause<'tcx>, Span)]> {
+    query explicit_item_self_bounds(key: DefId) -> ty::EarlyBinder<'tcx, &'tcx [(ty::Clause<'tcx>, Span)]> {
         desc { |tcx| "finding item bounds for `{}`", tcx.def_path_str(key) }
         cache_on_disk_if { key.is_local() }
         separate_provide_extern
@@ -427,11 +427,11 @@ rustc_queries! {
         desc { |tcx| "elaborating item bounds for `{}`", tcx.def_path_str(key) }
     }
 
-    query item_super_predicates(key: DefId) -> ty::EarlyBinder<'tcx, ty::Clauses<'tcx>> {
+    query item_self_bounds(key: DefId) -> ty::EarlyBinder<'tcx, ty::Clauses<'tcx>> {
         desc { |tcx| "elaborating item assumptions for `{}`", tcx.def_path_str(key) }
     }
 
-    query item_non_self_assumptions(key: DefId) -> ty::EarlyBinder<'tcx, ty::Clauses<'tcx>> {
+    query item_non_self_bounds(key: DefId) -> ty::EarlyBinder<'tcx, ty::Clauses<'tcx>> {
         desc { |tcx| "elaborating item assumptions for `{}`", tcx.def_path_str(key) }
     }
 

compiler/rustc_middle/src/ty/context.rs

@@ -345,6 +345,20 @@ impl<'tcx> Interner for TyCtxt<'tcx> {
         self.item_bounds(def_id).map_bound(IntoIterator::into_iter)
     }
 
+    fn item_self_bounds(
+        self,
+        def_id: DefId,
+    ) -> ty::EarlyBinder<'tcx, impl IntoIterator<Item = ty::Clause<'tcx>>> {
+        self.item_self_bounds(def_id).map_bound(IntoIterator::into_iter)
+    }
+
+    fn item_non_self_bounds(
+        self,
+        def_id: DefId,
+    ) -> ty::EarlyBinder<'tcx, impl IntoIterator<Item = ty::Clause<'tcx>>> {
+        self.item_non_self_bounds(def_id).map_bound(IntoIterator::into_iter)
+    }
+
     fn predicates_of(
         self,
         def_id: DefId,
@@ -2577,7 +2591,7 @@ impl<'tcx> TyCtxt<'tcx> {
         let ty::Alias(ty::Opaque, ty::AliasTy { def_id, .. }) = ty.kind() else { return false };
         let future_trait = self.require_lang_item(LangItem::Future, None);
 
-        self.explicit_item_super_predicates(def_id).skip_binder().iter().any(|&(predicate, _)| {
+        self.explicit_item_self_bounds(def_id).skip_binder().iter().any(|&(predicate, _)| {
             let ty::ClauseKind::Trait(trait_predicate) = predicate.kind().skip_binder() else {
                 return false;
             };

compiler/rustc_middle/src/ty/return_position_impl_trait_in_trait.rs

@@ -64,7 +64,7 @@ impl<'tcx> TyCtxt<'tcx> {
         args: ty::GenericArgsRef<'tcx>,
     ) -> &'tcx ty::List<ty::PolyExistentialPredicate<'tcx>> {
         let mut bounds: Vec<_> = self
-            .item_super_predicates(def_id)
+            .item_self_bounds(def_id)
             .iter_instantiated(self, args)
             .filter_map(|clause| {
                 clause