diff options
Diffstat (limited to 'compiler/rustc_borrowck/src/region_infer/opaque_types.rs')
| -rw-r--r-- | compiler/rustc_borrowck/src/region_infer/opaque_types.rs | 149 |
1 files changed, 83 insertions, 66 deletions
diff --git a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs index 7fc89e89a..1a227f2d1 100644 --- a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs +++ b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs @@ -61,7 +61,7 @@ impl<'tcx> RegionInferenceContext<'tcx> { pub(crate) fn infer_opaque_types( &self, infcx: &InferCtxt<'tcx>, - opaque_ty_decls: FxIndexMap<OpaqueTypeKey<'tcx>, (OpaqueHiddenType<'tcx>, OpaqueTyOrigin)>, + opaque_ty_decls: FxIndexMap<OpaqueTypeKey<'tcx>, OpaqueHiddenType<'tcx>>, ) -> FxIndexMap<LocalDefId, OpaqueHiddenType<'tcx>> { let mut result: FxIndexMap<LocalDefId, OpaqueHiddenType<'tcx>> = FxIndexMap::default(); @@ -72,7 +72,7 @@ impl<'tcx> RegionInferenceContext<'tcx> { .collect(); debug!(?member_constraints); - for (opaque_type_key, (concrete_type, origin)) in opaque_ty_decls { + for (opaque_type_key, concrete_type) in opaque_ty_decls { let substs = opaque_type_key.substs; debug!(?concrete_type, ?substs); @@ -92,7 +92,8 @@ impl<'tcx> RegionInferenceContext<'tcx> { } None => { subst_regions.push(vid); - infcx.tcx.mk_re_error_with_message( + ty::Region::new_error_with_message( + infcx.tcx, concrete_type.span, "opaque type with non-universal region substs", ) @@ -142,7 +143,6 @@ impl<'tcx> RegionInferenceContext<'tcx> { let ty = infcx.infer_opaque_definition_from_instantiation( opaque_type_key, universal_concrete_type, - origin, ); // Sometimes two opaque types are the same only after we remap the generic parameters // back to the opaque type definition. E.g. we may have `OpaqueType<X, Y>` mapped to `(X, Y)` @@ -158,7 +158,7 @@ impl<'tcx> RegionInferenceContext<'tcx> { ) .emit() }); - prev.ty = infcx.tcx.ty_error(guar); + prev.ty = Ty::new_error(infcx.tcx, guar); } // Pick a better span if there is one. // FIXME(oli-obk): collect multiple spans for better diagnostics down the road. @@ -214,7 +214,6 @@ pub trait InferCtxtExt<'tcx> { &self, opaque_type_key: OpaqueTypeKey<'tcx>, instantiated_ty: OpaqueHiddenType<'tcx>, - origin: OpaqueTyOrigin, ) -> Ty<'tcx>; } @@ -247,99 +246,117 @@ impl<'tcx> InferCtxtExt<'tcx> for InferCtxt<'tcx> { &self, opaque_type_key: OpaqueTypeKey<'tcx>, instantiated_ty: OpaqueHiddenType<'tcx>, - origin: OpaqueTyOrigin, ) -> Ty<'tcx> { if let Some(e) = self.tainted_by_errors() { - return self.tcx.ty_error(e); + return Ty::new_error(self.tcx, e); + } + + if let Err(guar) = + check_opaque_type_parameter_valid(self.tcx, opaque_type_key, instantiated_ty.span) + { + return Ty::new_error(self.tcx, guar); } let definition_ty = instantiated_ty .remap_generic_params_to_declaration_params(opaque_type_key, self.tcx, false) .ty; - if let Err(guar) = check_opaque_type_parameter_valid( + // `definition_ty` does not live in of the current inference context, + // so lets make sure that we don't accidentally misuse our current `infcx`. + match check_opaque_type_well_formed( self.tcx, - opaque_type_key, - origin, + self.next_trait_solver(), + opaque_type_key.def_id, instantiated_ty.span, + definition_ty, ) { - return self.tcx.ty_error(guar); + Ok(hidden_ty) => hidden_ty, + Err(guar) => Ty::new_error(self.tcx, guar), } + } +} - // Only check this for TAIT. RPIT already supports `tests/ui/impl-trait/nested-return-type2.rs` - // on stable and we'd break that. - let OpaqueTyOrigin::TyAlias { .. } = origin else { - return definition_ty; - }; - let def_id = opaque_type_key.def_id; - // This logic duplicates most of `check_opaque_meets_bounds`. - // FIXME(oli-obk): Also do region checks here and then consider removing `check_opaque_meets_bounds` entirely. - let param_env = self.tcx.param_env(def_id); - // HACK This bubble is required for this tests to pass: - // nested-return-type2-tait2.rs - // nested-return-type2-tait3.rs - let infcx = - self.tcx.infer_ctxt().with_opaque_type_inference(DefiningAnchor::Bubble).build(); - let ocx = ObligationCtxt::new(&infcx); - // Require the hidden type to be well-formed with only the generics of the opaque type. - // Defining use functions may have more bounds than the opaque type, which is ok, as long as the - // hidden type is well formed even without those bounds. - let predicate = ty::Binder::dummy(ty::PredicateKind::WellFormed(definition_ty.into())); - - let id_substs = InternalSubsts::identity_for_item(self.tcx, def_id); +/// This logic duplicates most of `check_opaque_meets_bounds`. +/// FIXME(oli-obk): Also do region checks here and then consider removing +/// `check_opaque_meets_bounds` entirely. +fn check_opaque_type_well_formed<'tcx>( + tcx: TyCtxt<'tcx>, + next_trait_solver: bool, + def_id: LocalDefId, + definition_span: Span, + definition_ty: Ty<'tcx>, +) -> Result<Ty<'tcx>, ErrorGuaranteed> { + // Only check this for TAIT. RPIT already supports `tests/ui/impl-trait/nested-return-type2.rs` + // on stable and we'd break that. + let opaque_ty_hir = tcx.hir().expect_item(def_id); + let OpaqueTyOrigin::TyAlias { .. } = opaque_ty_hir.expect_opaque_ty().origin else { + return Ok(definition_ty); + }; + let param_env = tcx.param_env(def_id); + // HACK This bubble is required for this tests to pass: + // nested-return-type2-tait2.rs + // nested-return-type2-tait3.rs + // FIXME(-Ztrait-solver=next): We probably should use `DefiningAnchor::Error` + // and prepopulate this `InferCtxt` with known opaque values, rather than + // using the `Bind` anchor here. For now it's fine. + let infcx = tcx + .infer_ctxt() + .with_next_trait_solver(next_trait_solver) + .with_opaque_type_inference(if next_trait_solver { + DefiningAnchor::Bind(def_id) + } else { + DefiningAnchor::Bubble + }) + .build(); + let ocx = ObligationCtxt::new(&infcx); + let identity_substs = InternalSubsts::identity_for_item(tcx, def_id); - // Require that the hidden type actually fulfills all the bounds of the opaque type, even without - // the bounds that the function supplies. - let opaque_ty = self.tcx.mk_opaque(def_id.to_def_id(), id_substs); - if let Err(err) = ocx.eq( - &ObligationCause::misc(instantiated_ty.span, def_id), - param_env, - opaque_ty, - definition_ty, - ) { + // Require that the hidden type actually fulfills all the bounds of the opaque type, even without + // the bounds that the function supplies. + let opaque_ty = Ty::new_opaque(tcx, def_id.to_def_id(), identity_substs); + ocx.eq(&ObligationCause::misc(definition_span, def_id), param_env, opaque_ty, definition_ty) + .map_err(|err| { infcx .err_ctxt() .report_mismatched_types( - &ObligationCause::misc(instantiated_ty.span, def_id), + &ObligationCause::misc(definition_span, def_id), opaque_ty, definition_ty, err, ) - .emit(); - } + .emit() + })?; - ocx.register_obligation(Obligation::misc( - infcx.tcx, - instantiated_ty.span, - def_id, - param_env, - predicate, - )); + // Require the hidden type to be well-formed with only the generics of the opaque type. + // Defining use functions may have more bounds than the opaque type, which is ok, as long as the + // hidden type is well formed even without those bounds. + let predicate = ty::Binder::dummy(ty::PredicateKind::Clause(ty::ClauseKind::WellFormed( + definition_ty.into(), + ))); + ocx.register_obligation(Obligation::misc(tcx, definition_span, def_id, param_env, predicate)); - // Check that all obligations are satisfied by the implementation's - // version. - let errors = ocx.select_all_or_error(); + // Check that all obligations are satisfied by the implementation's + // version. + let errors = ocx.select_all_or_error(); - // This is still required for many(half of the tests in ui/type-alias-impl-trait) - // tests to pass - let _ = infcx.take_opaque_types(); + // This is still required for many(half of the tests in ui/type-alias-impl-trait) + // tests to pass + let _ = infcx.take_opaque_types(); - if errors.is_empty() { - definition_ty - } else { - let reported = infcx.err_ctxt().report_fulfillment_errors(&errors); - self.tcx.ty_error(reported) - } + if errors.is_empty() { + Ok(definition_ty) + } else { + Err(infcx.err_ctxt().report_fulfillment_errors(&errors)) } } fn check_opaque_type_parameter_valid( tcx: TyCtxt<'_>, opaque_type_key: OpaqueTypeKey<'_>, - origin: OpaqueTyOrigin, span: Span, ) -> Result<(), ErrorGuaranteed> { - match origin { + let opaque_ty_hir = tcx.hir().expect_item(opaque_type_key.def_id); + match opaque_ty_hir.expect_opaque_ty().origin { // No need to check return position impl trait (RPIT) // because for type and const parameters they are correct // by construction: we convert |