diff --git a/compiler/rustc_middle/src/traits/mod.rs b/compiler/rustc_middle/src/traits/mod.rs index 0a77c3bc42fb9..8aa01801daf58 100644 --- a/compiler/rustc_middle/src/traits/mod.rs +++ b/compiler/rustc_middle/src/traits/mod.rs @@ -126,6 +126,15 @@ impl<'tcx> ObligationCause<'tcx> { self } + pub fn derived_host_cause( + mut self, + parent_host_pred: ty::Binder<'tcx, ty::HostEffectPredicate<'tcx>>, + variant: impl FnOnce(DerivedHostCause<'tcx>) -> ObligationCauseCode<'tcx>, + ) -> ObligationCause<'tcx> { + self.code = variant(DerivedHostCause { parent_host_pred, parent_code: self.code }).into(); + self + } + pub fn to_constraint_category(&self) -> ConstraintCategory<'tcx> { match self.code() { ObligationCauseCode::MatchImpl(cause, _) => cause.to_constraint_category(), @@ -279,6 +288,14 @@ pub enum ObligationCauseCode<'tcx> { /// Derived obligation for WF goals. WellFormedDerived(DerivedCause<'tcx>), + /// Derived obligation (i.e. `where` clause) on an user-provided impl + /// or a trait alias. + ImplDerivedHost(Box>), + + /// Derived obligation (i.e. `where` clause) on an user-provided impl + /// or a trait alias. + BuiltinDerivedHost(DerivedHostCause<'tcx>), + /// Derived obligation refined to point at a specific argument in /// a call or method expression. FunctionArg { @@ -438,36 +455,38 @@ pub enum WellFormedLoc { }, } -#[derive(Clone, Debug, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)] -#[derive(TypeVisitable, TypeFoldable)] -pub struct ImplDerivedCause<'tcx> { - pub derived: DerivedCause<'tcx>, - /// The `DefId` of the `impl` that gave rise to the `derived` obligation. - /// If the `derived` obligation arose from a trait alias, which conceptually has a synthetic impl, - /// then this will be the `DefId` of that trait alias. Care should therefore be taken to handle - /// that exceptional case where appropriate. - pub impl_or_alias_def_id: DefId, - /// The index of the derived predicate in the parent impl's predicates. - pub impl_def_predicate_index: Option, - pub span: Span, -} - impl<'tcx> ObligationCauseCode<'tcx> { /// Returns the base obligation, ignoring derived obligations. pub fn peel_derives(&self) -> &Self { let mut base_cause = self; - while let Some((parent_code, _)) = base_cause.parent() { + while let Some(parent_code) = base_cause.parent() { base_cause = parent_code; } base_cause } + pub fn parent(&self) -> Option<&Self> { + match self { + ObligationCauseCode::FunctionArg { parent_code, .. } => Some(parent_code), + ObligationCauseCode::BuiltinDerived(derived) + | ObligationCauseCode::WellFormedDerived(derived) + | ObligationCauseCode::ImplDerived(box ImplDerivedCause { derived, .. }) => { + Some(&derived.parent_code) + } + ObligationCauseCode::BuiltinDerivedHost(derived) + | ObligationCauseCode::ImplDerivedHost(box ImplDerivedHostCause { derived, .. }) => { + Some(&derived.parent_code) + } + _ => None, + } + } + /// Returns the base obligation and the base trait predicate, if any, ignoring /// derived obligations. pub fn peel_derives_with_predicate(&self) -> (&Self, Option>) { let mut base_cause = self; let mut base_trait_pred = None; - while let Some((parent_code, parent_pred)) = base_cause.parent() { + while let Some((parent_code, parent_pred)) = base_cause.parent_with_predicate() { base_cause = parent_code; if let Some(parent_pred) = parent_pred { base_trait_pred = Some(parent_pred); @@ -477,7 +496,7 @@ impl<'tcx> ObligationCauseCode<'tcx> { (base_cause, base_trait_pred) } - pub fn parent(&self) -> Option<(&Self, Option>)> { + pub fn parent_with_predicate(&self) -> Option<(&Self, Option>)> { match self { ObligationCauseCode::FunctionArg { parent_code, .. } => Some((parent_code, None)), ObligationCauseCode::BuiltinDerived(derived) @@ -555,6 +574,42 @@ pub struct DerivedCause<'tcx> { pub parent_code: InternedObligationCauseCode<'tcx>, } +#[derive(Clone, Debug, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)] +#[derive(TypeVisitable, TypeFoldable)] +pub struct ImplDerivedCause<'tcx> { + pub derived: DerivedCause<'tcx>, + /// The `DefId` of the `impl` that gave rise to the `derived` obligation. + /// If the `derived` obligation arose from a trait alias, which conceptually has a synthetic impl, + /// then this will be the `DefId` of that trait alias. Care should therefore be taken to handle + /// that exceptional case where appropriate. + pub impl_or_alias_def_id: DefId, + /// The index of the derived predicate in the parent impl's predicates. + pub impl_def_predicate_index: Option, + pub span: Span, +} + +#[derive(Clone, Debug, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)] +#[derive(TypeVisitable, TypeFoldable)] +pub struct DerivedHostCause<'tcx> { + /// The trait predicate of the parent obligation that led to the + /// current obligation. Note that only trait obligations lead to + /// derived obligations, so we just store the trait predicate here + /// directly. + pub parent_host_pred: ty::Binder<'tcx, ty::HostEffectPredicate<'tcx>>, + + /// The parent trait had this cause. + pub parent_code: InternedObligationCauseCode<'tcx>, +} + +#[derive(Clone, Debug, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)] +#[derive(TypeVisitable, TypeFoldable)] +pub struct ImplDerivedHostCause<'tcx> { + pub derived: DerivedHostCause<'tcx>, + /// The `DefId` of the `impl` that gave rise to the `derived` obligation. + pub impl_def_id: DefId, + pub span: Span, +} + #[derive(Clone, Debug, PartialEq, Eq, TypeVisitable)] pub enum SelectionError<'tcx> { /// The trait is not implemented. diff --git a/compiler/rustc_middle/src/ty/predicate.rs b/compiler/rustc_middle/src/ty/predicate.rs index 3ecaa3e22d39c..32d6455e82557 100644 --- a/compiler/rustc_middle/src/ty/predicate.rs +++ b/compiler/rustc_middle/src/ty/predicate.rs @@ -634,6 +634,28 @@ impl<'tcx> UpcastFrom, PolyProjectionPredicate<'tcx>> for Clause<'t } } +impl<'tcx> UpcastFrom, ty::Binder<'tcx, ty::HostEffectPredicate<'tcx>>> + for Predicate<'tcx> +{ + fn upcast_from( + from: ty::Binder<'tcx, ty::HostEffectPredicate<'tcx>>, + tcx: TyCtxt<'tcx>, + ) -> Self { + from.map_bound(ty::ClauseKind::HostEffect).upcast(tcx) + } +} + +impl<'tcx> UpcastFrom, ty::Binder<'tcx, ty::HostEffectPredicate<'tcx>>> + for Clause<'tcx> +{ + fn upcast_from( + from: ty::Binder<'tcx, ty::HostEffectPredicate<'tcx>>, + tcx: TyCtxt<'tcx>, + ) -> Self { + from.map_bound(ty::ClauseKind::HostEffect).upcast(tcx) + } +} + impl<'tcx> UpcastFrom, NormalizesTo<'tcx>> for Predicate<'tcx> { fn upcast_from(from: NormalizesTo<'tcx>, tcx: TyCtxt<'tcx>) -> Self { PredicateKind::NormalizesTo(from).upcast(tcx) diff --git a/compiler/rustc_next_trait_solver/src/solve/effect_goals.rs b/compiler/rustc_next_trait_solver/src/solve/effect_goals.rs index 81b5199002b23..9cffcb7c6b773 100644 --- a/compiler/rustc_next_trait_solver/src/solve/effect_goals.rs +++ b/compiler/rustc_next_trait_solver/src/solve/effect_goals.rs @@ -352,7 +352,7 @@ where ecx.probe_builtin_trait_candidate(BuiltinImplSource::Misc).enter(|ecx| { ecx.add_goals( - GoalSource::Misc, + GoalSource::ImplWhereBound, const_conditions.into_iter().map(|trait_ref| { goal.with( cx, diff --git a/compiler/rustc_trait_selection/src/error_reporting/traits/fulfillment_errors.rs b/compiler/rustc_trait_selection/src/error_reporting/traits/fulfillment_errors.rs index 4fb02f609438e..0e918e531ef3d 100644 --- a/compiler/rustc_trait_selection/src/error_reporting/traits/fulfillment_errors.rs +++ b/compiler/rustc_trait_selection/src/error_reporting/traits/fulfillment_errors.rs @@ -754,7 +754,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { applied_do_not_recommend = true; } } - if let Some((parent_cause, _parent_pred)) = base_cause.parent() { + if let Some(parent_cause) = base_cause.parent() { base_cause = parent_cause.clone(); } else { break; @@ -779,7 +779,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { trait_ref.skip_binder().args.type_at(1).to_opt_closure_kind() && !found_kind.extends(expected_kind) { - if let Some((_, Some(parent))) = obligation.cause.code().parent() { + if let Some((_, Some(parent))) = obligation.cause.code().parent_with_predicate() { // If we have a derived obligation, then the parent will be a `AsyncFn*` goal. trait_ref = parent.to_poly_trait_ref(); } else if let &ObligationCauseCode::FunctionArg { arg_hir_id, .. } = @@ -925,7 +925,8 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { let Some(typeck) = &self.typeck_results else { return false; }; - let Some((ObligationCauseCode::QuestionMark, Some(y))) = obligation.cause.code().parent() + let Some((ObligationCauseCode::QuestionMark, Some(y))) = + obligation.cause.code().parent_with_predicate() else { return false; }; @@ -1178,7 +1179,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { let mut code = obligation.cause.code(); let mut pred = obligation.predicate.as_trait_clause(); - while let Some((next_code, next_pred)) = code.parent() { + while let Some((next_code, next_pred)) = code.parent_with_predicate() { if let Some(pred) = pred { self.enter_forall(pred, |pred| { diag.note(format!( @@ -2093,7 +2094,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { let mut code = obligation.cause.code(); let mut trait_pred = trait_predicate; let mut peeled = false; - while let Some((parent_code, parent_trait_pred)) = code.parent() { + while let Some((parent_code, parent_trait_pred)) = code.parent_with_predicate() { code = parent_code; if let Some(parent_trait_pred) = parent_trait_pred { trait_pred = parent_trait_pred; diff --git a/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs b/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs index 94682f501a8c4..81333d95f57dd 100644 --- a/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs +++ b/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs @@ -460,7 +460,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { { // Suggest dereferencing the argument to a function/method call if possible let mut real_trait_pred = trait_pred; - while let Some((parent_code, parent_trait_pred)) = code.parent() { + while let Some((parent_code, parent_trait_pred)) = code.parent_with_predicate() { code = parent_code; if let Some(parent_trait_pred) = parent_trait_pred { real_trait_pred = parent_trait_pred; @@ -1476,7 +1476,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { let mut span = obligation.cause.span; let mut trait_pred = trait_pred; let mut code = obligation.cause.code(); - while let Some((c, Some(parent_trait_pred))) = code.parent() { + while let Some((c, Some(parent_trait_pred))) = code.parent_with_predicate() { // We want the root obligation, in order to detect properly handle // `for _ in &mut &mut vec![] {}`. code = c; @@ -3501,6 +3501,59 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { ) }); } + ObligationCauseCode::ImplDerivedHost(ref data) => { + let self_ty = + self.resolve_vars_if_possible(data.derived.parent_host_pred.self_ty()); + let msg = format!( + "required for `{self_ty}` to implement `{} {}`", + data.derived.parent_host_pred.skip_binder().constness, + data.derived + .parent_host_pred + .map_bound(|pred| pred.trait_ref) + .print_only_trait_path(), + ); + match tcx.hir().get_if_local(data.impl_def_id) { + Some(Node::Item(hir::Item { + kind: hir::ItemKind::Impl(hir::Impl { of_trait, self_ty, .. }), + .. + })) => { + let mut spans = vec![self_ty.span]; + spans.extend(of_trait.as_ref().map(|t| t.path.span)); + let mut spans: MultiSpan = spans.into(); + spans.push_span_label(data.span, "unsatisfied trait bound introduced here"); + err.span_note(spans, msg); + } + _ => { + err.note(msg); + } + } + ensure_sufficient_stack(|| { + self.note_obligation_cause_code( + body_id, + err, + data.derived.parent_host_pred, + param_env, + &data.derived.parent_code, + obligated_types, + seen_requirements, + long_ty_file, + ) + }); + } + ObligationCauseCode::BuiltinDerivedHost(ref data) => { + ensure_sufficient_stack(|| { + self.note_obligation_cause_code( + body_id, + err, + data.parent_host_pred, + param_env, + &data.parent_code, + obligated_types, + seen_requirements, + long_ty_file, + ) + }); + } ObligationCauseCode::WellFormedDerived(ref data) => { let parent_trait_ref = self.resolve_vars_if_possible(data.parent_trait_pred); let parent_predicate = parent_trait_ref; diff --git a/compiler/rustc_trait_selection/src/solve/fulfill.rs b/compiler/rustc_trait_selection/src/solve/fulfill.rs index 2b2623a050ec9..7aa82c52c9f26 100644 --- a/compiler/rustc_trait_selection/src/solve/fulfill.rs +++ b/compiler/rustc_trait_selection/src/solve/fulfill.rs @@ -474,8 +474,11 @@ impl<'tcx> ProofTreeVisitor<'tcx> for BestObligation<'tcx> { // for normalizes-to. let pred_kind = goal.goal().predicate.kind(); let child_mode = match pred_kind.skip_binder() { - ty::PredicateKind::Clause(ty::ClauseKind::Trait(parent_trait_pred)) => { - ChildMode::Trait(pred_kind.rebind(parent_trait_pred)) + ty::PredicateKind::Clause(ty::ClauseKind::Trait(pred)) => { + ChildMode::Trait(pred_kind.rebind(pred)) + } + ty::PredicateKind::Clause(ty::ClauseKind::HostEffect(pred)) => { + ChildMode::Host(pred_kind.rebind(pred)) } ty::PredicateKind::NormalizesTo(normalizes_to) if matches!( @@ -492,6 +495,7 @@ impl<'tcx> ProofTreeVisitor<'tcx> for BestObligation<'tcx> { }; let mut impl_where_bound_count = 0; + let mut impl_const_condition_bound_count = 0; for nested_goal in candidate.instantiate_nested_goals(self.span()) { trace!(nested_goal = ?(nested_goal.goal(), nested_goal.source(), nested_goal.result())); @@ -504,7 +508,7 @@ impl<'tcx> ProofTreeVisitor<'tcx> for BestObligation<'tcx> { let obligation; match (child_mode, nested_goal.source()) { - (ChildMode::Trait(_), GoalSource::Misc) => { + (ChildMode::Trait(_) | ChildMode::Host(_), GoalSource::Misc) => { continue; } (ChildMode::Trait(parent_trait_pred), GoalSource::ImplWhereBound) => { @@ -517,6 +521,16 @@ impl<'tcx> ProofTreeVisitor<'tcx> for BestObligation<'tcx> { )); impl_where_bound_count += 1; } + (ChildMode::Host(parent_host_pred), GoalSource::ImplWhereBound) => { + obligation = make_obligation(derive_host_cause( + tcx, + candidate.kind(), + self.obligation.cause.clone(), + impl_const_condition_bound_count, + parent_host_pred, + )); + impl_const_condition_bound_count += 1; + } // Skip over a higher-ranked predicate. (_, GoalSource::InstantiateHigherRanked) => { obligation = self.obligation.clone(); @@ -575,6 +589,10 @@ enum ChildMode<'tcx> { // and skip all `GoalSource::Misc`, which represent useless obligations // such as alias-eq which may not hold. Trait(ty::PolyTraitPredicate<'tcx>), + // Try to derive an `ObligationCause::{ImplDerived,BuiltinDerived}`, + // and skip all `GoalSource::Misc`, which represent useless obligations + // such as alias-eq which may not hold. + Host(ty::Binder<'tcx, ty::HostEffectPredicate<'tcx>>), // Skip trying to derive an `ObligationCause` from this obligation, and // report *all* sub-obligations as if they came directly from the parent // obligation. @@ -616,3 +634,52 @@ fn derive_cause<'tcx>( }; cause } + +fn derive_host_cause<'tcx>( + tcx: TyCtxt<'tcx>, + candidate_kind: inspect::ProbeKind>, + mut cause: ObligationCause<'tcx>, + idx: usize, + parent_host_pred: ty::Binder<'tcx, ty::HostEffectPredicate<'tcx>>, +) -> ObligationCause<'tcx> { + match candidate_kind { + inspect::ProbeKind::TraitCandidate { + source: CandidateSource::Impl(impl_def_id), + result: _, + } => { + if let Some((_, span)) = tcx + .predicates_of(impl_def_id) + .instantiate_identity(tcx) + .into_iter() + .chain(tcx.const_conditions(impl_def_id).instantiate_identity(tcx).into_iter().map( + |(trait_ref, span)| { + ( + trait_ref.to_host_effect_clause( + tcx, + parent_host_pred.skip_binder().constness, + ), + span, + ) + }, + )) + .nth(idx) + { + cause = + cause.derived_host_cause(parent_host_pred, |derived| { + ObligationCauseCode::ImplDerivedHost(Box::new( + traits::ImplDerivedHostCause { derived, impl_def_id, span }, + )) + }) + } + } + inspect::ProbeKind::TraitCandidate { + source: CandidateSource::BuiltinImpl(..), + result: _, + } => { + cause = + cause.derived_host_cause(parent_host_pred, ObligationCauseCode::BuiltinDerivedHost); + } + _ => {} + }; + cause +} diff --git a/compiler/rustc_trait_selection/src/traits/effects.rs b/compiler/rustc_trait_selection/src/traits/effects.rs index 07fb2efb7fed3..24d7f6adec6de 100644 --- a/compiler/rustc_trait_selection/src/traits/effects.rs +++ b/compiler/rustc_trait_selection/src/traits/effects.rs @@ -1,6 +1,8 @@ use rustc_hir as hir; use rustc_infer::infer::{BoundRegionConversionTime, DefineOpaqueTypes, InferCtxt}; -use rustc_infer::traits::{ImplSource, Obligation, PredicateObligation}; +use rustc_infer::traits::{ + ImplDerivedHostCause, ImplSource, Obligation, ObligationCauseCode, PredicateObligation, +}; use rustc_middle::span_bug; use rustc_middle::ty::fast_reject::DeepRejectCtxt; use rustc_middle::ty::{self, TypingMode}; @@ -137,9 +139,22 @@ fn evaluate_host_effect_from_selection_candiate<'tcx>( tcx.const_conditions(impl_.impl_def_id) .instantiate(tcx, impl_.args) .into_iter() - .map(|(trait_ref, _)| { - obligation.with( + .map(|(trait_ref, span)| { + Obligation::new( tcx, + obligation.cause.clone().derived_host_cause( + ty::Binder::dummy(obligation.predicate), + |derived| { + ObligationCauseCode::ImplDerivedHost(Box::new( + ImplDerivedHostCause { + derived, + impl_def_id: impl_.impl_def_id, + span, + }, + )) + }, + ), + obligation.param_env, trait_ref .to_host_effect_clause(tcx, obligation.predicate.constness), ) diff --git a/compiler/rustc_type_ir/src/binder.rs b/compiler/rustc_type_ir/src/binder.rs index c06a578d8ec70..484c9968d7565 100644 --- a/compiler/rustc_type_ir/src/binder.rs +++ b/compiler/rustc_type_ir/src/binder.rs @@ -91,6 +91,7 @@ impl_binder_encode_decode! { ty::ExistentialPredicate, ty::TraitRef, ty::ExistentialTraitRef, + ty::HostEffectPredicate, } impl Binder diff --git a/tests/ui/const-generics/issues/issue-88119.stderr b/tests/ui/const-generics/issues/issue-88119.stderr index 370244fe8c984..f219c90849a26 100644 --- a/tests/ui/const-generics/issues/issue-88119.stderr +++ b/tests/ui/const-generics/issues/issue-88119.stderr @@ -11,12 +11,30 @@ error[E0284]: type annotations needed: cannot normalize `<&T as ConstName>::{con | LL | impl const ConstName for &T | ^^ cannot normalize `<&T as ConstName>::{constant#0}` + | +note: required for `&T` to implement `~const ConstName` + --> $DIR/issue-88119.rs:19:35 + | +LL | impl const ConstName for &T + | ^^^^^^^^^ ^^ +LL | where +LL | [(); name_len::()]:, + | --------------------- unsatisfied trait bound introduced here error[E0284]: type annotations needed: cannot normalize `<&mut T as ConstName>::{constant#0}` --> $DIR/issue-88119.rs:26:49 | LL | impl const ConstName for &mut T | ^^^^^^ cannot normalize `<&mut T as ConstName>::{constant#0}` + | +note: required for `&mut T` to implement `~const ConstName` + --> $DIR/issue-88119.rs:26:35 + | +LL | impl const ConstName for &mut T + | ^^^^^^^^^ ^^^^^^ +LL | where +LL | [(); name_len::()]:, + | --------------------- unsatisfied trait bound introduced here error: aborting due to 3 previous errors diff --git a/tests/ui/traits/const-traits/assoc-type-const-bound-usage-fail.rs b/tests/ui/traits/const-traits/assoc-type-const-bound-usage-fail.rs index ce01086f0dc0b..fe375b25b8c8c 100644 --- a/tests/ui/traits/const-traits/assoc-type-const-bound-usage-fail.rs +++ b/tests/ui/traits/const-traits/assoc-type-const-bound-usage-fail.rs @@ -14,9 +14,9 @@ trait Trait { const fn unqualified() { T::Assoc::func(); - //~^ ERROR the trait bound `T: ~const Trait` is not satisfied + //~^ ERROR the trait bound `::Assoc: ~const Trait` is not satisfied ::Assoc::func(); - //~^ ERROR the trait bound `T: ~const Trait` is not satisfied + //~^ ERROR the trait bound `::Assoc: ~const Trait` is not satisfied } const fn works() { diff --git a/tests/ui/traits/const-traits/assoc-type-const-bound-usage-fail.stderr b/tests/ui/traits/const-traits/assoc-type-const-bound-usage-fail.stderr index 99fc924ad06b9..ce355083b90e4 100644 --- a/tests/ui/traits/const-traits/assoc-type-const-bound-usage-fail.stderr +++ b/tests/ui/traits/const-traits/assoc-type-const-bound-usage-fail.stderr @@ -1,10 +1,10 @@ -error[E0277]: the trait bound `T: ~const Trait` is not satisfied +error[E0277]: the trait bound `::Assoc: ~const Trait` is not satisfied --> $DIR/assoc-type-const-bound-usage-fail.rs:16:5 | LL | T::Assoc::func(); | ^^^^^^^^ -error[E0277]: the trait bound `T: ~const Trait` is not satisfied +error[E0277]: the trait bound `::Assoc: ~const Trait` is not satisfied --> $DIR/assoc-type-const-bound-usage-fail.rs:18:5 | LL | ::Assoc::func(); diff --git a/tests/ui/traits/const-traits/const-opaque.no.stderr b/tests/ui/traits/const-traits/const-opaque.no.stderr index 1278e1257467b..33aa1065df356 100644 --- a/tests/ui/traits/const-traits/const-opaque.no.stderr +++ b/tests/ui/traits/const-traits/const-opaque.no.stderr @@ -12,7 +12,7 @@ note: required by a bound in `bar` LL | const fn bar(t: T) -> impl ~const Foo { | ^^^^^^ required by this bound in `bar` -error[E0277]: the trait bound `(): const Foo` is not satisfied +error[E0277]: the trait bound `impl Foo: const Foo` is not satisfied --> $DIR/const-opaque.rs:33:12 | LL | opaque.method(); diff --git a/tests/ui/traits/const-traits/const-opaque.rs b/tests/ui/traits/const-traits/const-opaque.rs index 96cdd7d9f2619..bfcadd521a54e 100644 --- a/tests/ui/traits/const-traits/const-opaque.rs +++ b/tests/ui/traits/const-traits/const-opaque.rs @@ -31,7 +31,7 @@ const _: () = { let opaque = bar(()); //[no]~^ ERROR the trait bound `(): const Foo` is not satisfied opaque.method(); - //[no]~^ ERROR the trait bound `(): const Foo` is not satisfied + //[no]~^ ERROR the trait bound `impl Foo: const Foo` is not satisfied std::mem::forget(opaque); }; diff --git a/tests/ui/traits/const-traits/item-bound-entailment-fails.stderr b/tests/ui/traits/const-traits/item-bound-entailment-fails.stderr index 3fc6f58470947..0d53bc5897ef3 100644 --- a/tests/ui/traits/const-traits/item-bound-entailment-fails.stderr +++ b/tests/ui/traits/const-traits/item-bound-entailment-fails.stderr @@ -16,6 +16,11 @@ error[E0277]: the trait bound `T: ~const Bar` is not satisfied LL | type Assoc = C | ^^^^ | +note: required for `C` to implement `~const Bar` + --> $DIR/item-bound-entailment-fails.rs:14:15 + | +LL | impl const Bar for C where T: ~const Bar {} + | ^^^ ^^^^ ------ unsatisfied trait bound introduced here note: required by a bound in `Foo::Assoc` --> $DIR/item-bound-entailment-fails.rs:5:20 |