diff options
Diffstat (limited to 'compiler')
11 files changed, 97 insertions, 62 deletions
diff --git a/compiler/rustc_error_codes/src/error_codes/E0719.md b/compiler/rustc_error_codes/src/error_codes/E0719.md index cd981db1058..6aec38b42a3 100644 --- a/compiler/rustc_error_codes/src/error_codes/E0719.md +++ b/compiler/rustc_error_codes/src/error_codes/E0719.md @@ -1,4 +1,4 @@ -An associated type value was specified more than once. +An associated item was specified more than once in a trait object. Erroneous code example: @@ -7,21 +7,15 @@ trait FooTrait {} trait BarTrait {} // error: associated type `Item` in trait `Iterator` is specified twice -struct Foo<T: Iterator<Item: FooTrait, Item: BarTrait>> { f: T } +type Foo = dyn Iterator<Item = u32, Item = u32>; ``` -`Item` in trait `Iterator` cannot be specified multiple times for struct `Foo`. -To fix this, create a new trait that is a combination of the desired traits and -specify the associated type with the new trait. +To fix this, remove the duplicate specifier: Corrected example: ``` -trait FooTrait {} -trait BarTrait {} -trait FooBarTrait: FooTrait + BarTrait {} - -struct Foo<T: Iterator<Item: FooBarTrait>> { f: T } // ok! +type Foo = dyn Iterator<Item = u32>; // ok! ``` For more information about associated types, see [the book][bk-at]. For more diff --git a/compiler/rustc_hir_analysis/src/coherence/inherent_impls.rs b/compiler/rustc_hir_analysis/src/coherence/inherent_impls.rs index 38ae7852ca9..b069a74bf5a 100644 --- a/compiler/rustc_hir_analysis/src/coherence/inherent_impls.rs +++ b/compiler/rustc_hir_analysis/src/coherence/inherent_impls.rs @@ -195,11 +195,10 @@ impl<'tcx> InherentCollect<'tcx> { | ty::Closure(..) | ty::CoroutineClosure(..) | ty::Coroutine(..) - | ty::CoroutineWitness(..) - | ty::Alias(ty::Free, _) - | ty::Bound(..) - | ty::Placeholder(_) - | ty::Infer(_) => { + | ty::CoroutineWitness(..) => { + Err(self.tcx.dcx().delayed_bug("cannot define inherent `impl` for closure types")) + } + ty::Alias(ty::Free, _) | ty::Bound(..) | ty::Placeholder(_) | ty::Infer(_) => { bug!("unexpected impl self type of impl: {:?} {:?}", id, self_ty); } // We could bail out here, but that will silence other useful errors. diff --git a/compiler/rustc_hir_analysis/src/coherence/orphan.rs b/compiler/rustc_hir_analysis/src/coherence/orphan.rs index 621431ae234..5a61248cab8 100644 --- a/compiler/rustc_hir_analysis/src/coherence/orphan.rs +++ b/compiler/rustc_hir_analysis/src/coherence/orphan.rs @@ -230,10 +230,12 @@ pub(crate) fn orphan_check_impl( ty::Closure(..) | ty::CoroutineClosure(..) | ty::Coroutine(..) - | ty::CoroutineWitness(..) - | ty::Bound(..) - | ty::Placeholder(..) - | ty::Infer(..) => { + | ty::CoroutineWitness(..) => { + return Err(tcx + .dcx() + .delayed_bug("cannot define inherent `impl` for closure types")); + } + ty::Bound(..) | ty::Placeholder(..) | ty::Infer(..) => { let sp = tcx.def_span(impl_def_id); span_bug!(sp, "weird self type for autotrait impl") } diff --git a/compiler/rustc_hir_analysis/src/collect/item_bounds.rs b/compiler/rustc_hir_analysis/src/collect/item_bounds.rs index ba54fa8cc0d..9841fafc82c 100644 --- a/compiler/rustc_hir_analysis/src/collect/item_bounds.rs +++ b/compiler/rustc_hir_analysis/src/collect/item_bounds.rs @@ -12,7 +12,7 @@ use tracing::{debug, instrument}; use super::ItemCtxt; use super::predicates_of::assert_only_contains_predicates_from; -use crate::hir_ty_lowering::{HirTyLowerer, PredicateFilter}; +use crate::hir_ty_lowering::{HirTyLowerer, OverlappingAsssocItemConstraints, PredicateFilter}; /// For associated types we include both bounds written on the type /// (`type X: Trait`) and predicates from the trait: `where Self::X: Trait`. @@ -37,7 +37,14 @@ fn associated_type_bounds<'tcx>( let icx = ItemCtxt::new(tcx, assoc_item_def_id); let mut bounds = Vec::new(); - icx.lowerer().lower_bounds(item_ty, hir_bounds, &mut bounds, ty::List::empty(), filter); + icx.lowerer().lower_bounds( + item_ty, + hir_bounds, + &mut bounds, + ty::List::empty(), + filter, + OverlappingAsssocItemConstraints::Allowed, + ); match filter { PredicateFilter::All @@ -347,7 +354,14 @@ fn opaque_type_bounds<'tcx>( ty::print::with_reduced_queries!({ let icx = ItemCtxt::new(tcx, opaque_def_id); let mut bounds = Vec::new(); - icx.lowerer().lower_bounds(item_ty, hir_bounds, &mut bounds, ty::List::empty(), filter); + icx.lowerer().lower_bounds( + item_ty, + hir_bounds, + &mut bounds, + ty::List::empty(), + filter, + OverlappingAsssocItemConstraints::Allowed, + ); // Implicit bounds are added to opaque types unless a `?Trait` bound is found match filter { PredicateFilter::All diff --git a/compiler/rustc_hir_analysis/src/collect/predicates_of.rs b/compiler/rustc_hir_analysis/src/collect/predicates_of.rs index dd3590f9ac5..ffdf2a2f4c0 100644 --- a/compiler/rustc_hir_analysis/src/collect/predicates_of.rs +++ b/compiler/rustc_hir_analysis/src/collect/predicates_of.rs @@ -18,7 +18,9 @@ use super::item_bounds::explicit_item_bounds_with_filter; use crate::collect::ItemCtxt; use crate::constrained_generic_params as cgp; use crate::delegation::inherit_predicates_for_delegation_item; -use crate::hir_ty_lowering::{HirTyLowerer, PredicateFilter, RegionInferReason}; +use crate::hir_ty_lowering::{ + HirTyLowerer, OverlappingAsssocItemConstraints, PredicateFilter, RegionInferReason, +}; /// Returns a list of all type predicates (explicit and implicit) for the definition with /// ID `def_id`. This includes all predicates returned by `explicit_predicates_of`, plus @@ -187,6 +189,7 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Gen &mut bounds, ty::List::empty(), PredicateFilter::All, + OverlappingAsssocItemConstraints::Allowed, ); icx.lowerer().add_sizedness_bounds( &mut bounds, @@ -289,6 +292,7 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Gen &mut bounds, bound_vars, PredicateFilter::All, + OverlappingAsssocItemConstraints::Allowed, ); predicates.extend(bounds); } @@ -659,7 +663,14 @@ pub(super) fn implied_predicates_with_filter<'tcx>( let self_param_ty = tcx.types.self_param; let mut bounds = Vec::new(); - icx.lowerer().lower_bounds(self_param_ty, superbounds, &mut bounds, ty::List::empty(), filter); + icx.lowerer().lower_bounds( + self_param_ty, + superbounds, + &mut bounds, + ty::List::empty(), + filter, + OverlappingAsssocItemConstraints::Allowed, + ); match filter { PredicateFilter::All | PredicateFilter::SelfOnly @@ -984,6 +995,7 @@ impl<'tcx> ItemCtxt<'tcx> { &mut bounds, bound_vars, filter, + OverlappingAsssocItemConstraints::Allowed, ); } @@ -1063,6 +1075,7 @@ pub(super) fn const_conditions<'tcx>( &mut bounds, bound_vars, PredicateFilter::ConstIfConst, + OverlappingAsssocItemConstraints::Allowed, ); } _ => {} @@ -1083,6 +1096,7 @@ pub(super) fn const_conditions<'tcx>( &mut bounds, ty::List::empty(), PredicateFilter::ConstIfConst, + OverlappingAsssocItemConstraints::Allowed, ); } diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/bounds.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/bounds.rs index 99dc8e6e522..8682fdc5494 100644 --- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/bounds.rs +++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/bounds.rs @@ -21,7 +21,8 @@ use tracing::{debug, instrument}; use super::errors::GenericsArgsErrExtend; use crate::errors; use crate::hir_ty_lowering::{ - AssocItemQSelf, FeedConstTy, HirTyLowerer, PredicateFilter, RegionInferReason, + AssocItemQSelf, FeedConstTy, HirTyLowerer, OverlappingAsssocItemConstraints, PredicateFilter, + RegionInferReason, }; #[derive(Debug, Default)] @@ -338,6 +339,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { bounds: &mut Vec<(ty::Clause<'tcx>, Span)>, bound_vars: &'tcx ty::List<ty::BoundVariableKind>, predicate_filter: PredicateFilter, + overlapping_assoc_constraints: OverlappingAsssocItemConstraints, ) where 'tcx: 'hir, { @@ -362,6 +364,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { param_ty, bounds, predicate_filter, + overlapping_assoc_constraints, ); } hir::GenericBound::Outlives(lifetime) => { @@ -402,7 +405,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { trait_ref: ty::PolyTraitRef<'tcx>, constraint: &hir::AssocItemConstraint<'tcx>, bounds: &mut Vec<(ty::Clause<'tcx>, Span)>, - duplicates: &mut FxIndexMap<DefId, Span>, + duplicates: Option<&mut FxIndexMap<DefId, Span>>, path_span: Span, predicate_filter: PredicateFilter, ) -> Result<(), ErrorGuaranteed> { @@ -458,17 +461,19 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { ) .expect("failed to find associated item"); - duplicates - .entry(assoc_item.def_id) - .and_modify(|prev_span| { - self.dcx().emit_err(errors::ValueOfAssociatedStructAlreadySpecified { - span: constraint.span, - prev_span: *prev_span, - item_name: constraint.ident, - def_path: tcx.def_path_str(assoc_item.container_id(tcx)), - }); - }) - .or_insert(constraint.span); + if let Some(duplicates) = duplicates { + duplicates + .entry(assoc_item.def_id) + .and_modify(|prev_span| { + self.dcx().emit_err(errors::ValueOfAssociatedStructAlreadySpecified { + span: constraint.span, + prev_span: *prev_span, + item_name: constraint.ident, + def_path: tcx.def_path_str(assoc_item.container_id(tcx)), + }); + }) + .or_insert(constraint.span); + } let projection_term = if let ty::AssocTag::Fn = assoc_tag { let bound_vars = tcx.late_bound_vars(constraint.hir_id); @@ -600,6 +605,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { bounds, projection_ty.bound_vars(), predicate_filter, + OverlappingAsssocItemConstraints::Allowed, ); } PredicateFilter::SelfOnly diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/dyn_trait.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/dyn_trait.rs index c248cd7fec2..c0b13773089 100644 --- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/dyn_trait.rs +++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/dyn_trait.rs @@ -23,7 +23,9 @@ use tracing::{debug, instrument}; use super::HirTyLowerer; use crate::errors::SelfInTypeAlias; -use crate::hir_ty_lowering::{GenericArgCountMismatch, PredicateFilter, RegionInferReason}; +use crate::hir_ty_lowering::{ + GenericArgCountMismatch, OverlappingAsssocItemConstraints, PredicateFilter, RegionInferReason, +}; impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { /// Lower a trait object type from the HIR to our internal notion of a type. @@ -60,6 +62,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { dummy_self, &mut user_written_bounds, PredicateFilter::SelfOnly, + OverlappingAsssocItemConstraints::Forbidden, ); if let Err(GenericArgCountMismatch { invalid_args, .. }) = result.correct { potential_assoc_types.extend(invalid_args); @@ -157,10 +160,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { self.dcx() .struct_span_err( span, - format!( - "conflicting associated type bounds for `{item}` when \ - expanding trait alias" - ), + format!("conflicting associated type bounds for `{item}`"), ) .with_span_label( old_proj_span, diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs index 9b198d04454..eb660804c2b 100644 --- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs +++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs @@ -332,6 +332,15 @@ pub(crate) enum GenericArgPosition { MethodCall, } +/// Whether to allow duplicate associated iten constraints in a trait ref, e.g. +/// `Trait<Assoc = Ty, Assoc = Ty>`. This is forbidden in `dyn Trait<...>` +/// but allowed everywhere else. +#[derive(Clone, Copy, Debug, PartialEq)] +pub(crate) enum OverlappingAsssocItemConstraints { + Allowed, + Forbidden, +} + /// A marker denoting that the generic arguments that were /// provided did not match the respective generic parameters. #[derive(Clone, Debug)] @@ -752,6 +761,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { self_ty: Ty<'tcx>, bounds: &mut Vec<(ty::Clause<'tcx>, Span)>, predicate_filter: PredicateFilter, + overlapping_assoc_item_constraints: OverlappingAsssocItemConstraints, ) -> GenericArgCountResult { let tcx = self.tcx(); @@ -908,7 +918,10 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { } } - let mut dup_constraints = FxIndexMap::default(); + let mut dup_constraints = (overlapping_assoc_item_constraints + == OverlappingAsssocItemConstraints::Forbidden) + .then_some(FxIndexMap::default()); + for constraint in trait_segment.args().constraints { // Don't register any associated item constraints for negative bounds, // since we should have emitted an error for them earlier, and they @@ -927,7 +940,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { poly_trait_ref, constraint, bounds, - &mut dup_constraints, + dup_constraints.as_mut(), constraint.span, predicate_filter, ); @@ -2484,6 +2497,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { &mut bounds, ty::List::empty(), PredicateFilter::All, + OverlappingAsssocItemConstraints::Allowed, ); self.add_sizedness_bounds( &mut bounds, diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs index 833ce433d56..35253e4c291 100644 --- a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs +++ b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs @@ -611,19 +611,13 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { typeck_results.rvalue_scopes = rvalue_scopes; } - /// Unify the inference variables corresponding to coroutine witnesses, and save all the - /// predicates that were stalled on those inference variables. - /// - /// This process allows to conservatively save all predicates that do depend on the coroutine - /// interior types, for later processing by `check_coroutine_obligations`. - /// - /// We must not attempt to select obligations after this method has run, or risk query cycle - /// ICE. + /// Drain all obligations that are stalled on coroutines defined in this body. #[instrument(level = "debug", skip(self))] - pub(crate) fn resolve_coroutine_interiors(&self) { - // Try selecting all obligations that are not blocked on inference variables. - // Once we start unifying coroutine witnesses, trying to select obligations on them will - // trigger query cycle ICEs, as doing so requires MIR. + pub(crate) fn drain_stalled_coroutine_obligations(&self) { + // Make as much inference progress as possible before + // draining the stalled coroutine obligations as this may + // change obligations from being stalled on infer vars to + // being stalled on a coroutine. self.select_obligations_where_possible(|_| {}); let ty::TypingMode::Analysis { defining_opaque_types_and_generators } = self.typing_mode() diff --git a/compiler/rustc_hir_typeck/src/lib.rs b/compiler/rustc_hir_typeck/src/lib.rs index acc0481e457..9f5a85b6926 100644 --- a/compiler/rustc_hir_typeck/src/lib.rs +++ b/compiler/rustc_hir_typeck/src/lib.rs @@ -243,18 +243,15 @@ fn typeck_with_inspect<'tcx>( debug!(pending_obligations = ?fcx.fulfillment_cx.borrow().pending_obligations()); - // This must be the last thing before `report_ambiguity_errors`. - fcx.resolve_coroutine_interiors(); - - debug!(pending_obligations = ?fcx.fulfillment_cx.borrow().pending_obligations()); - // We need to handle opaque types before emitting ambiguity errors as applying // defining uses may guide type inference. if fcx.next_trait_solver() { fcx.handle_opaque_type_uses_next(); } - fcx.select_obligations_where_possible(|_| {}); + // This must be the last thing before `report_ambiguity_errors` below except `select_obligations_where_possible`. + // So don't put anything after this. + fcx.drain_stalled_coroutine_obligations(); if fcx.infcx.tainted_by_errors().is_none() { fcx.report_ambiguity_errors(); } diff --git a/compiler/rustc_type_ir/src/flags.rs b/compiler/rustc_type_ir/src/flags.rs index 24704c5bb53..ea3903d401e 100644 --- a/compiler/rustc_type_ir/src/flags.rs +++ b/compiler/rustc_type_ir/src/flags.rs @@ -347,6 +347,7 @@ impl<I: Interner> FlagComputation<I> { fn add_ty_pat(&mut self, pat: <I as Interner>::Pat) { self.add_flags(pat.flags()); + self.add_exclusive_binder(pat.outer_exclusive_binder()); } fn add_predicate(&mut self, binder: ty::Binder<I, ty::PredicateKind<I>>) { |