diff options
5 files changed, 94 insertions, 16 deletions
diff --git a/compiler/rustc_hir_analysis/src/astconv/mod.rs b/compiler/rustc_hir_analysis/src/astconv/mod.rs index 40c68953788..6cb008bc5f8 100644 --- a/compiler/rustc_hir_analysis/src/astconv/mod.rs +++ b/compiler/rustc_hir_analysis/src/astconv/mod.rs @@ -56,6 +56,9 @@ use std::slice; #[derive(Debug)] pub struct PathSeg(pub DefId, pub usize); +#[derive(Copy, Clone, Debug)] +pub struct OnlySelfBounds(pub bool); + pub trait AstConv<'tcx> { fn tcx(&self) -> TyCtxt<'tcx>; @@ -670,6 +673,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { args: &GenericArgs<'_>, infer_args: bool, self_ty: Ty<'tcx>, + only_self_bounds: OnlySelfBounds, ) -> GenericArgCountResult { let (substs, arg_count) = self.create_substs_for_ast_path( trait_ref_span, @@ -706,6 +710,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { &mut dup_bindings, binding_span.unwrap_or(binding.span), constness, + only_self_bounds, ); // Okay to ignore `Err` because of `ErrorGuaranteed` (see above). } @@ -741,6 +746,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { self_ty: Ty<'tcx>, bounds: &mut Bounds<'tcx>, speculative: bool, + only_self_bounds: OnlySelfBounds, ) -> GenericArgCountResult { let hir_id = trait_ref.hir_ref_id; let binding_span = None; @@ -766,6 +772,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { args, infer_args, self_ty, + only_self_bounds, ) } @@ -777,6 +784,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { args: &GenericArgs<'_>, self_ty: Ty<'tcx>, bounds: &mut Bounds<'tcx>, + only_self_bounds: OnlySelfBounds, ) { let binding_span = Some(span); let constness = ty::BoundConstness::NotConst; @@ -799,6 +807,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { args, infer_args, self_ty, + only_self_bounds, ); } @@ -947,6 +956,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { ast_bounds: I, bounds: &mut Bounds<'tcx>, bound_vars: &'tcx ty::List<ty::BoundVariableKind>, + only_self_bounds: OnlySelfBounds, ) { for ast_bound in ast_bounds { match ast_bound { @@ -964,11 +974,18 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { param_ty, bounds, false, + only_self_bounds, ); } &hir::GenericBound::LangItemTrait(lang_item, span, hir_id, args) => { self.instantiate_lang_item_trait_ref( - lang_item, span, hir_id, args, param_ty, bounds, + lang_item, + span, + hir_id, + args, + param_ty, + bounds, + only_self_bounds, ); } hir::GenericBound::Outlives(lifetime) => { @@ -1006,9 +1023,16 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { &self, param_ty: Ty<'tcx>, ast_bounds: &[hir::GenericBound<'_>], + only_self_bounds: OnlySelfBounds, ) -> Bounds<'tcx> { let mut bounds = Bounds::default(); - self.add_bounds(param_ty, ast_bounds.iter(), &mut bounds, ty::List::empty()); + self.add_bounds( + param_ty, + ast_bounds.iter(), + &mut bounds, + ty::List::empty(), + only_self_bounds, + ); debug!(?bounds); bounds @@ -1034,7 +1058,13 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } let mut bounds = Bounds::default(); - self.add_bounds(param_ty, result.iter(), &mut bounds, ty::List::empty()); + self.add_bounds( + param_ty, + result.iter(), + &mut bounds, + ty::List::empty(), + OnlySelfBounds(true), + ); debug!(?bounds); bounds @@ -1057,6 +1087,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { dup_bindings: &mut FxHashMap<DefId, Span>, path_span: Span, constness: ty::BoundConstness, + only_self_bounds: OnlySelfBounds, ) -> Result<(), ErrorGuaranteed> { // Given something like `U: SomeTrait<T = X>`, we want to produce a // predicate like `<U as SomeTrait>::T = X`. This is somewhat @@ -1356,8 +1387,20 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { // // Calling `skip_binder` is okay, because `add_bounds` expects the `param_ty` // parameter to have a skipped binder. - let param_ty = tcx.mk_alias(ty::Projection, projection_ty.skip_binder()); - self.add_bounds(param_ty, ast_bounds.iter(), bounds, projection_ty.bound_vars()); + // + // NOTE: If `only_self_bounds` is true, do NOT expand this associated + // type bound into a trait predicate, since we only want to add predicates + // for the `Self` type. + if !only_self_bounds.0 { + let param_ty = tcx.mk_alias(ty::Projection, projection_ty.skip_binder()); + self.add_bounds( + param_ty, + ast_bounds.iter(), + bounds, + projection_ty.bound_vars(), + only_self_bounds, + ); + } } } Ok(()) @@ -1398,6 +1441,10 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { dummy_self, &mut bounds, false, + // FIXME: This should be `true`, but we don't really handle + // associated type bounds or type aliases in objects in a way + // that makes this meaningful, I think. + OnlySelfBounds(false), ) { potential_assoc_types.extend(cur_potential_assoc_types); } diff --git a/compiler/rustc_hir_analysis/src/collect/item_bounds.rs b/compiler/rustc_hir_analysis/src/collect/item_bounds.rs index 80d6bc7db9e..948b903e509 100644 --- a/compiler/rustc_hir_analysis/src/collect/item_bounds.rs +++ b/compiler/rustc_hir_analysis/src/collect/item_bounds.rs @@ -1,5 +1,5 @@ use super::ItemCtxt; -use crate::astconv::AstConv; +use crate::astconv::{AstConv, OnlySelfBounds}; use rustc_hir as hir; use rustc_infer::traits::util; use rustc_middle::ty::subst::InternalSubsts; @@ -26,7 +26,7 @@ fn associated_type_bounds<'tcx>( ); let icx = ItemCtxt::new(tcx, assoc_item_def_id); - let mut bounds = icx.astconv().compute_bounds(item_ty, ast_bounds); + let mut bounds = icx.astconv().compute_bounds(item_ty, ast_bounds, OnlySelfBounds(false)); // Associated types are implicitly sized unless a `?Sized` bound is found icx.astconv().add_implicitly_sized(&mut bounds, item_ty, ast_bounds, None, span); @@ -67,7 +67,7 @@ fn opaque_type_bounds<'tcx>( ) -> &'tcx [(ty::Predicate<'tcx>, Span)] { ty::print::with_no_queries!({ let icx = ItemCtxt::new(tcx, opaque_def_id); - let mut bounds = icx.astconv().compute_bounds(item_ty, ast_bounds); + let mut bounds = icx.astconv().compute_bounds(item_ty, ast_bounds, OnlySelfBounds(false)); // Opaque types are implicitly sized unless a `?Sized` bound is found icx.astconv().add_implicitly_sized(&mut bounds, item_ty, ast_bounds, None, span); debug!(?bounds); diff --git a/compiler/rustc_hir_analysis/src/collect/predicates_of.rs b/compiler/rustc_hir_analysis/src/collect/predicates_of.rs index 935b561945c..b142e4ae1a6 100644 --- a/compiler/rustc_hir_analysis/src/collect/predicates_of.rs +++ b/compiler/rustc_hir_analysis/src/collect/predicates_of.rs @@ -1,4 +1,4 @@ -use crate::astconv::AstConv; +use crate::astconv::{AstConv, OnlySelfBounds}; use crate::bounds::Bounds; use crate::collect::ItemCtxt; use crate::constrained_generic_params as cgp; @@ -14,9 +14,6 @@ use rustc_middle::ty::{GenericPredicates, ToPredicate}; use rustc_span::symbol::{sym, Ident}; use rustc_span::{Span, DUMMY_SP}; -#[derive(Debug)] -struct OnlySelfBounds(bool); - /// Returns a list of all type predicates (explicit and implicit) for the definition with /// ID `def_id`. This includes all predicates returned by `predicates_defined_on`, plus /// `Self: Trait` predicates for traits. @@ -225,7 +222,13 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Gen } let mut bounds = Bounds::default(); - icx.astconv().add_bounds(ty, bound_pred.bounds.iter(), &mut bounds, bound_vars); + icx.astconv().add_bounds( + ty, + bound_pred.bounds.iter(), + &mut bounds, + bound_vars, + OnlySelfBounds(false), + ); predicates.extend(bounds.predicates()); } @@ -608,7 +611,7 @@ pub(super) fn implied_predicates_with_filter( let (superbounds, where_bounds_that_match) = match filter { PredicateFilter::All => ( // Convert the bounds that follow the colon (or equal in trait aliases) - icx.astconv().compute_bounds(self_param_ty, bounds), + icx.astconv().compute_bounds(self_param_ty, bounds, OnlySelfBounds(false)), // Also include all where clause bounds icx.type_parameter_bounds_in_generics( generics, @@ -620,7 +623,7 @@ pub(super) fn implied_predicates_with_filter( ), PredicateFilter::SelfOnly => ( // Convert the bounds that follow the colon (or equal in trait aliases) - icx.astconv().compute_bounds(self_param_ty, bounds), + icx.astconv().compute_bounds(self_param_ty, bounds, OnlySelfBounds(true)), // Include where clause bounds for `Self` icx.type_parameter_bounds_in_generics( generics, @@ -798,6 +801,7 @@ impl<'tcx> ItemCtxt<'tcx> { }), &mut bounds, bound_vars, + only_self_bounds, ); } diff --git a/compiler/rustc_hir_analysis/src/lib.rs b/compiler/rustc_hir_analysis/src/lib.rs index a4b797f77f7..961457b7579 100644 --- a/compiler/rustc_hir_analysis/src/lib.rs +++ b/compiler/rustc_hir_analysis/src/lib.rs @@ -116,7 +116,7 @@ use rustc_trait_selection::traits::{self, ObligationCause, ObligationCauseCode, use std::ops::Not; -use astconv::AstConv; +use astconv::{AstConv, OnlySelfBounds}; use bounds::Bounds; fluent_messages! { "../messages.ftl" } @@ -531,6 +531,7 @@ pub fn hir_trait_to_predicates<'tcx>( self_ty, &mut bounds, true, + OnlySelfBounds(false), ); bounds diff --git a/tests/ui/associated-type-bounds/supertrait-defines-ty.rs b/tests/ui/associated-type-bounds/supertrait-defines-ty.rs new file mode 100644 index 00000000000..b6f37cb908e --- /dev/null +++ b/tests/ui/associated-type-bounds/supertrait-defines-ty.rs @@ -0,0 +1,26 @@ +// check-pass + +// Make sure that we don't look into associated type bounds when looking for +// supertraits that define an associated type. Fixes #76593. + +#![feature(associated_type_bounds)] + +trait Load: Sized { + type Blob; +} + +trait Primitive: Load<Blob = Self> {} + +trait BlobPtr: Primitive {} + +trait CleanPtr: Load<Blob: BlobPtr> { + fn to_blob(&self) -> Self::Blob; +} + +impl Load for () { + type Blob = Self; +} +impl Primitive for () {} +impl BlobPtr for () {} + +fn main() {} |