Rollup merge of #135902 - compiler-errors:item-non-self-bound-in-new-solver, r=lcnr

Do not consider child bound assumptions for rigid alias

r? lcnr

See first commit for the important details. For second commit, I also stacked a somewhat opinionated name change, though I can separate that if needed.

Fixes https://github.com/rust-lang/trait-system-refactor-initiative/issues/149

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,
+        item_self_bounds: item_bounds::item_self_bounds,
-        explicit_item_super_predicates: item_bounds::explicit_item_super_predicates,
+        explicit_item_self_bounds: item_bounds::explicit_item_self_bounds,
-        item_non_self_assumptions: item_bounds::item_non_self_assumptions,
+        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<_> =
+    let own_bounds: FxIndexSet<_> = tcx.item_self_bounds(def_id).skip_binder().iter().collect();
-        tcx.item_super_predicates(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)),
                 ),
@@ -1019,7 +1019,7 @@ 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(
+                    fcx.tcx.item_self_bounds(rpit_def_id).iter_identity().filter_map(|clause| {
-                        |clause| {
+                        let predicate = clause
-                            let predicate = clause
+                            .kind()
-                                .kind()
+                            .map_bound(|clause| match clause {
-                                .map_bound(|clause| match clause {
+                                ty::ClauseKind::Trait(trait_pred) => Some(ty::ClauseKind::Trait(
-                                    ty::ClauseKind::Trait(trait_pred) => Some(
+                                    trait_pred.with_self_ty(fcx.tcx, ty),
-                                        ty::ClauseKind::Trait(trait_pred.with_self_ty(fcx.tcx, ty)),
+                                )),
-                                    ),
+                                ty::ClauseKind::Projection(proj_pred) => Some(
-                                    ty::ClauseKind::Projection(proj_pred) => {
+                                    ty::ClauseKind::Projection(proj_pred.with_self_ty(fcx.tcx, ty)),
-                                        Some(ty::ClauseKind::Projection(
+                                ),
-                                            proj_pred.with_self_ty(fcx.tcx, ty),
+                                _ => None,
-                                        ))
+                            })
-                                    }
+                            .transpose()?;
-                                    _ => None,
+                        Some(Obligation::new(
-                                })
+                            fcx.tcx,
-                                .transpose()?;
+                            ObligationCause::dummy(),
-                            Some(Obligation::new(
+                            fcx.param_env,
-                                fcx.tcx,
+                            predicate,
-                                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(
+                    elaborate(cx.tcx, cx.tcx.explicit_item_self_bounds(def).iter_identity_copied())
-                        cx.tcx,
+                        // We only care about self bounds for the impl-trait
-                        cx.tcx.explicit_item_super_predicates(def).iter_identity_copied(),
+                        .filter_only_self()
-                    )
+                        .find_map(|(pred, _span)| {
-                    // We only care about self bounds for the impl-trait
+                            // We only look at the `DefId`, so it is safe to skip the binder here.
-                    .filter_only_self()
+                            if let ty::ClauseKind::Trait(ref poly_trait_predicate) =
-                    .find_map(|(pred, _span)| {
+                                pred.kind().skip_binder()
-                        // We only look at the `DefId`, so it is safe to skip the binder here.
+                            {
-                        if let ty::ClauseKind::Trait(ref poly_trait_predicate) =
+                                let def_id = poly_trait_predicate.trait_ref.def_id;
-                            pred.kind().skip_binder()
-                        {
-                            let def_id = poly_trait_predicate.trait_ref.def_id;
 
-                            is_def_must_use(cx, def_id, span)
+                                is_def_must_use(cx, def_id, span)
-                        } else {
+                            } else {
-                            None
+                                None
-                        }
+                            }
-                    })
+                        })
-                    .map(|inner| MustUsePath::Opaque(Box::new(inner)))
+                        .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) {
+    fn encode_explicit_item_self_bounds(&mut self, def_id: DefId) {
-        debug!("EncodeContext::encode_explicit_item_super_predicates({:?})", def_id);
+        debug!("EncodeContext::encode_explicit_item_self_bounds({:?})", def_id);
-        let bounds = self.tcx.explicit_item_super_predicates(def_id).skip_binder();
+        let bounds = self.tcx.explicit_item_self_bounds(def_id).skip_binder();
-        record_defaulted_array!(self.tables.explicit_item_super_predicates[def_id] <- bounds);
+        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

compiler/rustc_next_trait_solver/src/solve/assembly/mod.rs

@@ -19,6 +19,11 @@ use crate::solve::{
     MaybeCause, NoSolution, QueryResult,
 };
 
+enum AliasBoundKind {
+    SelfBounds,
+    NonSelfBounds,
+}
+
 /// A candidate is a possible way to prove a goal.
 ///
 /// It consists of both the `source`, which describes how that goal would be proven,
@@ -510,7 +515,12 @@ where
         candidates: &mut Vec<Candidate<I>>,
     ) {
         let () = self.probe(|_| ProbeKind::NormalizedSelfTyAssembly).enter(|ecx| {
-            ecx.assemble_alias_bound_candidates_recur(goal.predicate.self_ty(), goal, candidates);
+            ecx.assemble_alias_bound_candidates_recur(
+                goal.predicate.self_ty(),
+                goal,
+                candidates,
+                AliasBoundKind::SelfBounds,
+            );
         });
     }
 
@@ -528,6 +538,7 @@ where
         self_ty: I::Ty,
         goal: Goal<I, G>,
         candidates: &mut Vec<Candidate<I>>,
+        consider_self_bounds: AliasBoundKind,
     ) {
         let (kind, alias_ty) = match self_ty.kind() {
             ty::Bool
@@ -580,16 +591,37 @@ where
             }
         };
 
-        for assumption in
+        match consider_self_bounds {
-            self.cx().item_bounds(alias_ty.def_id).iter_instantiated(self.cx(), alias_ty.args)
+            AliasBoundKind::SelfBounds => {
-        {
+                for assumption in self
-            candidates.extend(G::probe_and_consider_implied_clause(
+                    .cx()
-                self,
+                    .item_self_bounds(alias_ty.def_id)
-                CandidateSource::AliasBound,
+                    .iter_instantiated(self.cx(), alias_ty.args)
-                goal,
+                {
-                assumption,
+                    candidates.extend(G::probe_and_consider_implied_clause(
-                [],
+                        self,
-            ));
+                        CandidateSource::AliasBound,
+                        goal,
+                        assumption,
+                        [],
+                    ));
+                }
+            }
+            AliasBoundKind::NonSelfBounds => {
+                for assumption in self
+                    .cx()
+                    .item_non_self_bounds(alias_ty.def_id)
+                    .iter_instantiated(self.cx(), alias_ty.args)
+                {
+                    candidates.extend(G::probe_and_consider_implied_clause(
+                        self,
+                        CandidateSource::AliasBound,
+                        goal,
+                        assumption,
+                        [],
+                    ));
+                }
+            }
         }
 
         candidates.extend(G::consider_additional_alias_assumptions(self, goal, alias_ty));
@@ -600,9 +632,12 @@ where
 
         // Recurse on the self type of the projection.
         match self.structurally_normalize_ty(goal.param_env, alias_ty.self_ty()) {
-            Ok(next_self_ty) => {
+            Ok(next_self_ty) => self.assemble_alias_bound_candidates_recur(
-                self.assemble_alias_bound_candidates_recur(next_self_ty, goal, candidates)
+                next_self_ty,
-            }
+                goal,
+                candidates,
+                AliasBoundKind::NonSelfBounds,
+            ),
             Err(NoSolution) => {}
         }
     }

compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs

@@ -196,7 +196,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
         let item_def_id = self.tcx.associated_item_def_ids(future_trait)[0];
 
         self.tcx
-            .explicit_item_super_predicates(def_id)
+            .explicit_item_self_bounds(def_id)
             .iter_instantiated_copied(self.tcx, args)
             .find_map(|(predicate, _)| {
                 predicate

compiler/rustc_trait_selection/src/error_reporting/infer/note_and_explain.rs

@@ -293,7 +293,7 @@ impl<T> Trait<T> for X {
                     (ty::Dynamic(t, _, ty::DynKind::Dyn), ty::Alias(ty::Opaque, alias))
                         if let Some(def_id) = t.principal_def_id()
                             && tcx
-                                .explicit_item_super_predicates(alias.def_id)
+                                .explicit_item_self_bounds(alias.def_id)
                                 .skip_binder()
                                 .iter()
                                 .any(|(pred, _span)| match pred.kind().skip_binder() {
@@ -422,7 +422,7 @@ impl<T> Trait<T> for X {
                             ty::Alias(..) => values.expected,
                             _ => values.found,
                         };
-                        let preds = tcx.explicit_item_super_predicates(opaque_ty.def_id);
+                        let preds = tcx.explicit_item_self_bounds(opaque_ty.def_id);
                         for (pred, _span) in preds.skip_binder() {
                             let ty::ClauseKind::Trait(trait_predicate) = pred.kind().skip_binder()
                             else {

compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs

@@ -1087,28 +1087,27 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
                         sig_parts.map_bound(|sig| sig.tupled_inputs_ty.tuple_fields().as_slice()),
                     ))
                 }
-                ty::Alias(ty::Opaque, ty::AliasTy { def_id, args, .. }) => self
+                ty::Alias(ty::Opaque, ty::AliasTy { def_id, args, .. }) => {
-                    .tcx
+                    self.tcx.item_self_bounds(def_id).instantiate(self.tcx, args).iter().find_map(
-                    .item_super_predicates(def_id)
+                        |pred| {
-                    .instantiate(self.tcx, args)
+                            if let ty::ClauseKind::Projection(proj) = pred.kind().skip_binder()
-                    .iter()
-                    .find_map(|pred| {
-                        if let ty::ClauseKind::Projection(proj) = pred.kind().skip_binder()
                             && self
                                 .tcx
                                 .is_lang_item(proj.projection_term.def_id, LangItem::FnOnceOutput)
                             // args tuple will always be args[1]
                             && let ty::Tuple(args) = proj.projection_term.args.type_at(1).kind()
-                        {
+                            {
-                            Some((
+                                Some((
-                                DefIdOrName::DefId(def_id),
+                                    DefIdOrName::DefId(def_id),
-                                pred.kind().rebind(proj.term.expect_type()),
+                                    pred.kind().rebind(proj.term.expect_type()),
-                                pred.kind().rebind(args.as_slice()),
+                                    pred.kind().rebind(args.as_slice()),
-                            ))
+                                ))
-                        } else {
+                            } else {
-                            None
+                                None
-                        }
+                            }
-                    }),
+                        },
+                    )
+                }
                 ty::Dynamic(data, _, ty::Dyn) => data.iter().find_map(|pred| {
                     if let ty::ExistentialPredicate::Projection(proj) = pred.skip_binder()
                         && self.tcx.is_lang_item(proj.def_id, LangItem::FnOnceOutput)

compiler/rustc_trait_selection/src/traits/select/mod.rs

@@ -1620,9 +1620,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             // projections, we will never be able to equate, e.g. `<T as Tr>::A`
             // with `<<T as Tr>::A as Tr>::A`.
             let relevant_bounds = if in_parent_alias_type {
-                self.tcx().item_non_self_assumptions(alias_ty.def_id)
+                self.tcx().item_non_self_bounds(alias_ty.def_id)
             } else {
-                self.tcx().item_super_predicates(alias_ty.def_id)
+                self.tcx().item_self_bounds(alias_ty.def_id)
             };
 
             for bound in relevant_bounds.instantiate(self.tcx(), alias_ty.args) {

compiler/rustc_type_ir/src/interner.rs

@@ -203,6 +203,16 @@ pub trait Interner:
         def_id: Self::DefId,
     ) -> ty::EarlyBinder<Self, impl IntoIterator<Item = Self::Clause>>;
 
+    fn item_self_bounds(
+        self,
+        def_id: Self::DefId,
+    ) -> ty::EarlyBinder<Self, impl IntoIterator<Item = Self::Clause>>;
+
+    fn item_non_self_bounds(
+        self,
+        def_id: Self::DefId,
+    ) -> ty::EarlyBinder<Self, impl IntoIterator<Item = Self::Clause>>;
+
     fn predicates_of(
         self,
         def_id: Self::DefId,

src/tools/clippy/clippy_lints/src/future_not_send.rs

@@ -79,7 +79,7 @@ impl<'tcx> LateLintPass<'tcx> for FutureNotSend {
             && let Some(future_trait) = cx.tcx.lang_items().future_trait()
             && let Some(send_trait) = cx.tcx.get_diagnostic_item(sym::Send)
         {
-            let preds = cx.tcx.explicit_item_super_predicates(def_id);
+            let preds = cx.tcx.explicit_item_self_bounds(def_id);
             let is_future = preds.iter_instantiated_copied(cx.tcx, args).any(|(p, _)| {
                 p.as_trait_clause()
                     .is_some_and(|trait_pred| trait_pred.skip_binder().trait_ref.def_id == future_trait)

src/tools/clippy/clippy_utils/src/ty/mod.rs

@@ -96,7 +96,7 @@ pub fn contains_ty_adt_constructor_opaque<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'
                         return false;
                     }
 
-                    for (predicate, _span) in cx.tcx.explicit_item_super_predicates(def_id).iter_identity_copied() {
+                    for (predicate, _span) in cx.tcx.explicit_item_self_bounds(def_id).iter_identity_copied() {
                         match predicate.kind().skip_binder() {
                             // For `impl Trait<U>`, it will register a predicate of `T: Trait<U>`, so we go through
                             // and check substitutions to find `U`.
@@ -322,7 +322,7 @@ pub fn is_must_use_ty<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool {
         },
         ty::Tuple(args) => args.iter().any(|ty| is_must_use_ty(cx, ty)),
         ty::Alias(ty::Opaque, AliasTy { def_id, .. }) => {
-            for (predicate, _) in cx.tcx.explicit_item_super_predicates(def_id).skip_binder() {
+            for (predicate, _) in cx.tcx.explicit_item_self_bounds(def_id).skip_binder() {
                 if let ty::ClauseKind::Trait(trait_predicate) = predicate.kind().skip_binder() {
                     if cx.tcx.has_attr(trait_predicate.trait_ref.def_id, sym::must_use) {
                         return true;
@@ -712,7 +712,7 @@ pub fn ty_sig<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> Option<ExprFnSig<'t
         ty::Alias(ty::Opaque, AliasTy { def_id, args, .. }) => sig_from_bounds(
             cx,
             ty,
-            cx.tcx.item_super_predicates(def_id).iter_instantiated(cx.tcx, args),
+            cx.tcx.item_self_bounds(def_id).iter_instantiated(cx.tcx, args),
             cx.tcx.opt_parent(def_id),
         ),
         ty::FnPtr(sig_tys, hdr) => Some(ExprFnSig::Sig(sig_tys.with(hdr), None)),

tests/ui/associated-type-bounds/cant-see-copy-bound-from-child-rigid.current.stderr

@@ -1,5 +1,5 @@
 error[E0382]: use of moved value: `x`
-  --> $DIR/cant-see-copy-bound-from-child-rigid.rs:14:9
+  --> $DIR/cant-see-copy-bound-from-child-rigid.rs:18:9
    |
 LL | fn foo<T: Trait>(x: T::Assoc) -> (T::Assoc, T::Assoc)
    |                  - move occurs because `x` has type `<T as Trait>::Assoc`, which does not implement the `Copy` trait

tests/ui/associated-type-bounds/cant-see-copy-bound-from-child-rigid.next.stderr

@@ -0,0 +1,14 @@
+error[E0382]: use of moved value: `x`
+  --> $DIR/cant-see-copy-bound-from-child-rigid.rs:18:9
+   |
+LL | fn foo<T: Trait>(x: T::Assoc) -> (T::Assoc, T::Assoc)
+   |                  - move occurs because `x` has type `<T as Trait>::Assoc`, which does not implement the `Copy` trait
+...
+LL |     (x, x)
+   |      -  ^ value used here after move
+   |      |
+   |      value moved here
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0382`.

tests/ui/associated-type-bounds/cant-see-copy-bound-from-child-rigid.rs

@@ -1,3 +1,7 @@
+//@ revisions: current next
+//@ ignore-compare-mode-next-solver (explicit revisions)
+//@[next] compile-flags: -Znext-solver
+
 trait Id {
     type This: ?Sized;
 }

tests/ui/traits/const-traits/const-impl-trait.stderr

@@ -99,26 +99,6 @@ note: `PartialEq` can't be used with `~const` because it isn't annotated with `#
   --> $SRC_DIR/core/src/cmp.rs:LL:COL
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
-error: `~const` can only be applied to `#[const_trait]` traits
-  --> $DIR/const-impl-trait.rs:23:22
-   |
-LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
-   |                      ^^^^^^ can't be applied to `PartialEq`
-   |
-note: `PartialEq` can't be used with `~const` because it isn't annotated with `#[const_trait]`
-  --> $SRC_DIR/core/src/cmp.rs:LL:COL
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: `~const` can only be applied to `#[const_trait]` traits
-  --> $DIR/const-impl-trait.rs:23:22
-   |
-LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
-   |                      ^^^^^^ can't be applied to `PartialEq`
-   |
-note: `PartialEq` can't be used with `~const` because it isn't annotated with `#[const_trait]`
-  --> $SRC_DIR/core/src/cmp.rs:LL:COL
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
 error: `~const` can only be applied to `#[const_trait]` traits
   --> $DIR/const-impl-trait.rs:27:22
    |
@@ -149,6 +129,36 @@ note: `PartialEq` can't be used with `~const` because it isn't annotated with `#
   --> $SRC_DIR/core/src/cmp.rs:LL:COL
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:23:22
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
+   |                      ^^^^^^ can't be applied to `PartialEq`
+   |
+note: `PartialEq` can't be used with `~const` because it isn't annotated with `#[const_trait]`
+  --> $SRC_DIR/core/src/cmp.rs:LL:COL
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:23:22
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
+   |                      ^^^^^^ can't be applied to `PartialEq`
+   |
+note: `PartialEq` can't be used with `~const` because it isn't annotated with `#[const_trait]`
+  --> $SRC_DIR/core/src/cmp.rs:LL:COL
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:23:22
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
+   |                      ^^^^^^ can't be applied to `PartialEq`
+   |
+note: `PartialEq` can't be used with `~const` because it isn't annotated with `#[const_trait]`
+  --> $SRC_DIR/core/src/cmp.rs:LL:COL
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
 error[E0015]: cannot call non-const operator in constants
   --> $DIR/const-impl-trait.rs:35:13
    |
@@ -181,7 +191,7 @@ LL |     a == a
    |
    = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants
 
-error: aborting due to 20 previous errors
+error: aborting due to 21 previous errors
 
 Some errors have detailed explanations: E0015, E0635.
 For more information about an error, try `rustc --explain E0015`.