diff options
Diffstat (limited to 'compiler/rustc_trait_selection')
10 files changed, 308 insertions, 378 deletions
diff --git a/compiler/rustc_trait_selection/src/infer.rs b/compiler/rustc_trait_selection/src/infer.rs index 91c91d4e52f..1b58c9b864e 100644 --- a/compiler/rustc_trait_selection/src/infer.rs +++ b/compiler/rustc_trait_selection/src/infer.rs @@ -177,18 +177,10 @@ impl<'tcx> InferCtxtBuilderExt<'tcx> for InferCtxtBuilder<'tcx> { R: Debug + TypeFoldable<'tcx>, Canonical<'tcx, QueryResponse<'tcx, R>>: ArenaAllocatable<'tcx>, { - self.enter_with_canonical( - DUMMY_SP, - canonical_key, - |ref infcx, key, canonical_inference_vars| { - let mut fulfill_cx = <dyn TraitEngine<'_>>::new(infcx.tcx); - let value = operation(infcx, &mut *fulfill_cx, key)?; - infcx.make_canonicalized_query_response( - canonical_inference_vars, - value, - &mut *fulfill_cx, - ) - }, - ) + let (ref infcx, key, canonical_inference_vars) = + self.build_with_canonical(DUMMY_SP, canonical_key); + let mut fulfill_cx = <dyn TraitEngine<'_>>::new(infcx.tcx); + let value = operation(infcx, &mut *fulfill_cx, key)?; + infcx.make_canonicalized_query_response(canonical_inference_vars, value, &mut *fulfill_cx) } } diff --git a/compiler/rustc_trait_selection/src/traits/auto_trait.rs b/compiler/rustc_trait_selection/src/traits/auto_trait.rs index c02265ffdd7..c716c4b0be9 100644 --- a/compiler/rustc_trait_selection/src/traits/auto_trait.rs +++ b/compiler/rustc_trait_selection/src/traits/auto_trait.rs @@ -10,7 +10,7 @@ use crate::traits::project::ProjectAndUnifyResult; use rustc_middle::mir::interpret::ErrorHandled; use rustc_middle::ty::fold::{TypeFolder, TypeSuperFoldable}; use rustc_middle::ty::visit::TypeVisitable; -use rustc_middle::ty::{Region, RegionVid}; +use rustc_middle::ty::{PolyTraitRef, Region, RegionVid}; use rustc_data_structures::fx::{FxHashMap, FxHashSet}; @@ -90,143 +90,105 @@ impl<'tcx> AutoTraitFinder<'tcx> { let trait_pred = ty::Binder::dummy(trait_ref); - let bail_out = tcx.infer_ctxt().enter(|infcx| { - let mut selcx = SelectionContext::new(&infcx); - let result = selcx.select(&Obligation::new( - ObligationCause::dummy(), - orig_env, - trait_pred.to_poly_trait_predicate(), - )); - - match result { - Ok(Some(ImplSource::UserDefined(_))) => { - debug!( - "find_auto_trait_generics({:?}): \ - manual impl found, bailing out", - trait_ref - ); - return true; - } - _ => {} + let infcx = tcx.infer_ctxt().build(); + let mut selcx = SelectionContext::new(&infcx); + for f in [ + PolyTraitRef::to_poly_trait_predicate, + PolyTraitRef::to_poly_trait_predicate_negative_polarity, + ] { + let result = + selcx.select(&Obligation::new(ObligationCause::dummy(), orig_env, f(&trait_pred))); + if let Ok(Some(ImplSource::UserDefined(_))) = result { + debug!( + "find_auto_trait_generics({:?}): \ + manual impl found, bailing out", + trait_ref + ); + // If an explicit impl exists, it always takes priority over an auto impl + return AutoTraitResult::ExplicitImpl; } - - let result = selcx.select(&Obligation::new( - ObligationCause::dummy(), - orig_env, - trait_pred.to_poly_trait_predicate_negative_polarity(), - )); - - match result { - Ok(Some(ImplSource::UserDefined(_))) => { - debug!( - "find_auto_trait_generics({:?}): \ - manual impl found, bailing out", - trait_ref - ); - true - } - _ => false, - } - }); - - // If an explicit impl exists, it always takes priority over an auto impl - if bail_out { - return AutoTraitResult::ExplicitImpl; } - tcx.infer_ctxt().enter(|infcx| { - let mut fresh_preds = FxHashSet::default(); + let infcx = tcx.infer_ctxt().build(); + let mut fresh_preds = FxHashSet::default(); + + // Due to the way projections are handled by SelectionContext, we need to run + // evaluate_predicates twice: once on the original param env, and once on the result of + // the first evaluate_predicates call. + // + // The problem is this: most of rustc, including SelectionContext and traits::project, + // are designed to work with a concrete usage of a type (e.g., Vec<u8> + // fn<T>() { Vec<T> }. This information will generally never change - given + // the 'T' in fn<T>() { ... }, we'll never know anything else about 'T'. + // If we're unable to prove that 'T' implements a particular trait, we're done - + // there's nothing left to do but error out. + // + // However, synthesizing an auto trait impl works differently. Here, we start out with + // a set of initial conditions - the ParamEnv of the struct/enum/union we're dealing + // with - and progressively discover the conditions we need to fulfill for it to + // implement a certain auto trait. This ends up breaking two assumptions made by trait + // selection and projection: + // + // * We can always cache the result of a particular trait selection for the lifetime of + // an InfCtxt + // * Given a projection bound such as '<T as SomeTrait>::SomeItem = K', if 'T: + // SomeTrait' doesn't hold, then we don't need to care about the 'SomeItem = K' + // + // We fix the first assumption by manually clearing out all of the InferCtxt's caches + // in between calls to SelectionContext.select. This allows us to keep all of the + // intermediate types we create bound to the 'tcx lifetime, rather than needing to lift + // them between calls. + // + // We fix the second assumption by reprocessing the result of our first call to + // evaluate_predicates. Using the example of '<T as SomeTrait>::SomeItem = K', our first + // pass will pick up 'T: SomeTrait', but not 'SomeItem = K'. On our second pass, + // traits::project will see that 'T: SomeTrait' is in our ParamEnv, allowing + // SelectionContext to return it back to us. + + let Some((new_env, user_env)) = self.evaluate_predicates( + &infcx, + trait_did, + ty, + orig_env, + orig_env, + &mut fresh_preds, + false, + ) else { + return AutoTraitResult::NegativeImpl; + }; + + let (full_env, full_user_env) = self + .evaluate_predicates(&infcx, trait_did, ty, new_env, user_env, &mut fresh_preds, true) + .unwrap_or_else(|| { + panic!("Failed to fully process: {:?} {:?} {:?}", ty, trait_did, orig_env) + }); - // Due to the way projections are handled by SelectionContext, we need to run - // evaluate_predicates twice: once on the original param env, and once on the result of - // the first evaluate_predicates call. - // - // The problem is this: most of rustc, including SelectionContext and traits::project, - // are designed to work with a concrete usage of a type (e.g., Vec<u8> - // fn<T>() { Vec<T> }. This information will generally never change - given - // the 'T' in fn<T>() { ... }, we'll never know anything else about 'T'. - // If we're unable to prove that 'T' implements a particular trait, we're done - - // there's nothing left to do but error out. - // - // However, synthesizing an auto trait impl works differently. Here, we start out with - // a set of initial conditions - the ParamEnv of the struct/enum/union we're dealing - // with - and progressively discover the conditions we need to fulfill for it to - // implement a certain auto trait. This ends up breaking two assumptions made by trait - // selection and projection: - // - // * We can always cache the result of a particular trait selection for the lifetime of - // an InfCtxt - // * Given a projection bound such as '<T as SomeTrait>::SomeItem = K', if 'T: - // SomeTrait' doesn't hold, then we don't need to care about the 'SomeItem = K' - // - // We fix the first assumption by manually clearing out all of the InferCtxt's caches - // in between calls to SelectionContext.select. This allows us to keep all of the - // intermediate types we create bound to the 'tcx lifetime, rather than needing to lift - // them between calls. - // - // We fix the second assumption by reprocessing the result of our first call to - // evaluate_predicates. Using the example of '<T as SomeTrait>::SomeItem = K', our first - // pass will pick up 'T: SomeTrait', but not 'SomeItem = K'. On our second pass, - // traits::project will see that 'T: SomeTrait' is in our ParamEnv, allowing - // SelectionContext to return it back to us. - - let Some((new_env, user_env)) = self.evaluate_predicates( - &infcx, - trait_did, - ty, - orig_env, - orig_env, - &mut fresh_preds, - false, - ) else { - return AutoTraitResult::NegativeImpl; - }; - - let (full_env, full_user_env) = self - .evaluate_predicates( - &infcx, - trait_did, - ty, - new_env, - user_env, - &mut fresh_preds, - true, - ) - .unwrap_or_else(|| { - panic!("Failed to fully process: {:?} {:?} {:?}", ty, trait_did, orig_env) - }); - - debug!( - "find_auto_trait_generics({:?}): fulfilling \ - with {:?}", - trait_ref, full_env - ); - infcx.clear_caches(); - - // At this point, we already have all of the bounds we need. FulfillmentContext is used - // to store all of the necessary region/lifetime bounds in the InferContext, as well as - // an additional sanity check. - let errors = - super::fully_solve_bound(&infcx, ObligationCause::dummy(), full_env, ty, trait_did); - if !errors.is_empty() { - panic!("Unable to fulfill trait {:?} for '{:?}': {:?}", trait_did, ty, errors); - } + debug!( + "find_auto_trait_generics({:?}): fulfilling \ + with {:?}", + trait_ref, full_env + ); + infcx.clear_caches(); + + // At this point, we already have all of the bounds we need. FulfillmentContext is used + // to store all of the necessary region/lifetime bounds in the InferContext, as well as + // an additional sanity check. + let errors = + super::fully_solve_bound(&infcx, ObligationCause::dummy(), full_env, ty, trait_did); + if !errors.is_empty() { + panic!("Unable to fulfill trait {:?} for '{:?}': {:?}", trait_did, ty, errors); + } - infcx.process_registered_region_obligations(&Default::default(), full_env); + infcx.process_registered_region_obligations(&Default::default(), full_env); - let region_data = infcx - .inner - .borrow_mut() - .unwrap_region_constraints() - .region_constraint_data() - .clone(); + let region_data = + infcx.inner.borrow_mut().unwrap_region_constraints().region_constraint_data().clone(); - let vid_to_region = self.map_vid_to_region(®ion_data); + let vid_to_region = self.map_vid_to_region(®ion_data); - let info = AutoTraitInfo { full_user_env, region_data, vid_to_region }; + let info = AutoTraitInfo { full_user_env, region_data, vid_to_region }; - AutoTraitResult::PositiveImpl(auto_trait_callback(info)) - }) + AutoTraitResult::PositiveImpl(auto_trait_callback(info)) } } diff --git a/compiler/rustc_trait_selection/src/traits/codegen.rs b/compiler/rustc_trait_selection/src/traits/codegen.rs index dde7527302c..8a62bf01567 100644 --- a/compiler/rustc_trait_selection/src/traits/codegen.rs +++ b/compiler/rustc_trait_selection/src/traits/codegen.rs @@ -29,60 +29,61 @@ pub fn codegen_select_candidate<'tcx>( // Do the initial selection for the obligation. This yields the // shallow result we are looking for -- that is, what specific impl. - let mut infcx_builder = - tcx.infer_ctxt().ignoring_regions().with_opaque_type_inference(DefiningAnchor::Bubble); - infcx_builder.enter(|infcx| { - //~^ HACK `Bubble` is required for - // this test to pass: type-alias-impl-trait/assoc-projection-ice.rs - let mut selcx = SelectionContext::new(&infcx); + let infcx = tcx + .infer_ctxt() + .ignoring_regions() + .with_opaque_type_inference(DefiningAnchor::Bubble) + .build(); + //~^ HACK `Bubble` is required for + // this test to pass: type-alias-impl-trait/assoc-projection-ice.rs + let mut selcx = SelectionContext::new(&infcx); - let obligation_cause = ObligationCause::dummy(); - let obligation = - Obligation::new(obligation_cause, param_env, trait_ref.to_poly_trait_predicate()); + let obligation_cause = ObligationCause::dummy(); + let obligation = + Obligation::new(obligation_cause, param_env, trait_ref.to_poly_trait_predicate()); - let selection = match selcx.select(&obligation) { - Ok(Some(selection)) => selection, - Ok(None) => return Err(CodegenObligationError::Ambiguity), - Err(Unimplemented) => return Err(CodegenObligationError::Unimplemented), - Err(e) => { - bug!("Encountered error `{:?}` selecting `{:?}` during codegen", e, trait_ref) - } - }; + let selection = match selcx.select(&obligation) { + Ok(Some(selection)) => selection, + Ok(None) => return Err(CodegenObligationError::Ambiguity), + Err(Unimplemented) => return Err(CodegenObligationError::Unimplemented), + Err(e) => { + bug!("Encountered error `{:?}` selecting `{:?}` during codegen", e, trait_ref) + } + }; - debug!(?selection); + debug!(?selection); - // Currently, we use a fulfillment context to completely resolve - // all nested obligations. This is because they can inform the - // inference of the impl's type parameters. - let mut fulfill_cx = <dyn TraitEngine<'tcx>>::new(tcx); - let impl_source = selection.map(|predicate| { - fulfill_cx.register_predicate_obligation(&infcx, predicate); - }); + // Currently, we use a fulfillment context to completely resolve + // all nested obligations. This is because they can inform the + // inference of the impl's type parameters. + let mut fulfill_cx = <dyn TraitEngine<'tcx>>::new(tcx); + let impl_source = selection.map(|predicate| { + fulfill_cx.register_predicate_obligation(&infcx, predicate); + }); - // In principle, we only need to do this so long as `impl_source` - // contains unbound type parameters. It could be a slight - // optimization to stop iterating early. - let errors = fulfill_cx.select_all_or_error(&infcx); - if !errors.is_empty() { - // `rustc_monomorphize::collector` assumes there are no type errors. - // Cycle errors are the only post-monomorphization errors possible; emit them now so - // `rustc_ty_utils::resolve_associated_item` doesn't return `None` post-monomorphization. - for err in errors { - if let FulfillmentErrorCode::CodeCycle(cycle) = err.code { - infcx.err_ctxt().report_overflow_error_cycle(&cycle); - } + // In principle, we only need to do this so long as `impl_source` + // contains unbound type parameters. It could be a slight + // optimization to stop iterating early. + let errors = fulfill_cx.select_all_or_error(&infcx); + if !errors.is_empty() { + // `rustc_monomorphize::collector` assumes there are no type errors. + // Cycle errors are the only post-monomorphization errors possible; emit them now so + // `rustc_ty_utils::resolve_associated_item` doesn't return `None` post-monomorphization. + for err in errors { + if let FulfillmentErrorCode::CodeCycle(cycle) = err.code { + infcx.err_ctxt().report_overflow_error_cycle(&cycle); } - return Err(CodegenObligationError::FulfillmentError); } + return Err(CodegenObligationError::FulfillmentError); + } - let impl_source = infcx.resolve_vars_if_possible(impl_source); - let impl_source = infcx.tcx.erase_regions(impl_source); + let impl_source = infcx.resolve_vars_if_possible(impl_source); + let impl_source = infcx.tcx.erase_regions(impl_source); - // Opaque types may have gotten their hidden types constrained, but we can ignore them safely - // as they will get constrained elsewhere, too. - // (ouz-a) This is required for `type-alias-impl-trait/assoc-projection-ice.rs` to pass - let _ = infcx.inner.borrow_mut().opaque_type_storage.take_opaque_types(); + // Opaque types may have gotten their hidden types constrained, but we can ignore them safely + // as they will get constrained elsewhere, too. + // (ouz-a) This is required for `type-alias-impl-trait/assoc-projection-ice.rs` to pass + let _ = infcx.inner.borrow_mut().opaque_type_storage.take_opaque_types(); - Ok(&*tcx.arena.alloc(impl_source)) - }) + Ok(&*tcx.arena.alloc(impl_source)) } diff --git a/compiler/rustc_trait_selection/src/traits/coherence.rs b/compiler/rustc_trait_selection/src/traits/coherence.rs index c3144ff6b07..7fc5c2ed0ea 100644 --- a/compiler/rustc_trait_selection/src/traits/coherence.rs +++ b/compiler/rustc_trait_selection/src/traits/coherence.rs @@ -100,11 +100,10 @@ where return no_overlap(); } - let overlaps = tcx.infer_ctxt().enter(|infcx| { - let selcx = &mut SelectionContext::intercrate(&infcx); - overlap(selcx, skip_leak_check, impl1_def_id, impl2_def_id, overlap_mode).is_some() - }); - + let infcx = tcx.infer_ctxt().build(); + let selcx = &mut SelectionContext::intercrate(&infcx); + let overlaps = + overlap(selcx, skip_leak_check, impl1_def_id, impl2_def_id, overlap_mode).is_some(); if !overlaps { return no_overlap(); } @@ -112,13 +111,10 @@ where // In the case where we detect an error, run the check again, but // this time tracking intercrate ambiguity causes for better // diagnostics. (These take time and can lead to false errors.) - tcx.infer_ctxt().enter(|infcx| { - let selcx = &mut SelectionContext::intercrate(&infcx); - selcx.enable_tracking_intercrate_ambiguity_causes(); - on_overlap( - overlap(selcx, skip_leak_check, impl1_def_id, impl2_def_id, overlap_mode).unwrap(), - ) - }) + let infcx = tcx.infer_ctxt().build(); + let selcx = &mut SelectionContext::intercrate(&infcx); + selcx.enable_tracking_intercrate_ambiguity_causes(); + on_overlap(overlap(selcx, skip_leak_check, impl1_def_id, impl2_def_id, overlap_mode).unwrap()) } fn with_fresh_ty_vars<'cx, 'tcx>( @@ -298,33 +294,32 @@ fn negative_impl<'cx, 'tcx>( let tcx = selcx.infcx().tcx; // Create an infcx, taking the predicates of impl1 as assumptions: - tcx.infer_ctxt().enter(|infcx| { - // create a parameter environment corresponding to a (placeholder) instantiation of impl1 - let impl_env = tcx.param_env(impl1_def_id); - let subject1 = match traits::fully_normalize( - &infcx, - ObligationCause::dummy(), - impl_env, - tcx.impl_subject(impl1_def_id), - ) { - Ok(s) => s, - Err(err) => { - tcx.sess.delay_span_bug( - tcx.def_span(impl1_def_id), - format!("failed to fully normalize {:?}: {:?}", impl1_def_id, err), - ); - return false; - } - }; + let infcx = tcx.infer_ctxt().build(); + // create a parameter environment corresponding to a (placeholder) instantiation of impl1 + let impl_env = tcx.param_env(impl1_def_id); + let subject1 = match traits::fully_normalize( + &infcx, + ObligationCause::dummy(), + impl_env, + tcx.impl_subject(impl1_def_id), + ) { + Ok(s) => s, + Err(err) => { + tcx.sess.delay_span_bug( + tcx.def_span(impl1_def_id), + format!("failed to fully normalize {:?}: {:?}", impl1_def_id, err), + ); + return false; + } + }; - // Attempt to prove that impl2 applies, given all of the above. - let selcx = &mut SelectionContext::new(&infcx); - let impl2_substs = infcx.fresh_substs_for_item(DUMMY_SP, impl2_def_id); - let (subject2, obligations) = - impl_subject_and_oblig(selcx, impl_env, impl2_def_id, impl2_substs); + // Attempt to prove that impl2 applies, given all of the above. + let selcx = &mut SelectionContext::new(&infcx); + let impl2_substs = infcx.fresh_substs_for_item(DUMMY_SP, impl2_def_id); + let (subject2, obligations) = + impl_subject_and_oblig(selcx, impl_env, impl2_def_id, impl2_substs); - !equate(&infcx, impl_env, subject1, subject2, obligations, impl1_def_id) - }) + !equate(&infcx, impl_env, subject1, subject2, obligations, impl1_def_id) } fn equate<'tcx>( diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs index e7270bd7c2d..5b4fa1df426 100644 --- a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs @@ -1930,16 +1930,11 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> { } let normalize = |candidate| { - self.tcx.infer_ctxt().enter(|ref infcx| { - let normalized = infcx - .at(&ObligationCause::dummy(), ty::ParamEnv::empty()) - .normalize(candidate) - .ok(); - match normalized { - Some(normalized) => normalized.value, - None => candidate, - } - }) + let infcx = self.tcx.infer_ctxt().build(); + infcx + .at(&ObligationCause::dummy(), ty::ParamEnv::empty()) + .normalize(candidate) + .map_or(candidate, |normalized| normalized.value) }; // Sort impl candidates so that ordering is consistent for UI tests. diff --git a/compiler/rustc_trait_selection/src/traits/misc.rs b/compiler/rustc_trait_selection/src/traits/misc.rs index f0346e4ae69..be603c609cb 100644 --- a/compiler/rustc_trait_selection/src/traits/misc.rs +++ b/compiler/rustc_trait_selection/src/traits/misc.rs @@ -23,65 +23,64 @@ pub fn can_type_implement_copy<'tcx>( parent_cause: ObligationCause<'tcx>, ) -> Result<(), CopyImplementationError<'tcx>> { // FIXME: (@jroesch) float this code up - tcx.infer_ctxt().enter(|infcx| { - let (adt, substs) = match self_type.kind() { - // These types used to have a builtin impl. - // Now libcore provides that impl. - ty::Uint(_) - | ty::Int(_) - | ty::Bool - | ty::Float(_) - | ty::Char - | ty::RawPtr(..) - | ty::Never - | ty::Ref(_, _, hir::Mutability::Not) - | ty::Array(..) => return Ok(()), + let infcx = tcx.infer_ctxt().build(); + let (adt, substs) = match self_type.kind() { + // These types used to have a builtin impl. + // Now libcore provides that impl. + ty::Uint(_) + | ty::Int(_) + | ty::Bool + | ty::Float(_) + | ty::Char + | ty::RawPtr(..) + | ty::Never + | ty::Ref(_, _, hir::Mutability::Not) + | ty::Array(..) => return Ok(()), - ty::Adt(adt, substs) => (adt, substs), + ty::Adt(adt, substs) => (adt, substs), - _ => return Err(CopyImplementationError::NotAnAdt), - }; + _ => return Err(CopyImplementationError::NotAnAdt), + }; - let mut infringing = Vec::new(); - for variant in adt.variants() { - for field in &variant.fields { - let ty = field.ty(tcx, substs); - if ty.references_error() { - continue; - } - let span = tcx.def_span(field.did); - // FIXME(compiler-errors): This gives us better spans for bad - // projection types like in issue-50480. - // If the ADT has substs, point to the cause we are given. - // If it does not, then this field probably doesn't normalize - // to begin with, and point to the bad field's span instead. - let cause = if field - .ty(tcx, traits::InternalSubsts::identity_for_item(tcx, adt.did())) - .has_non_region_param() - { - parent_cause.clone() - } else { - ObligationCause::dummy_with_span(span) - }; - match traits::fully_normalize(&infcx, cause, param_env, ty) { - Ok(ty) => { - if !infcx.type_is_copy_modulo_regions(param_env, ty, span) { - infringing.push((field, ty)); - } - } - Err(errors) => { - infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); - } - }; + let mut infringing = Vec::new(); + for variant in adt.variants() { + for field in &variant.fields { + let ty = field.ty(tcx, substs); + if ty.references_error() { + continue; } + let span = tcx.def_span(field.did); + // FIXME(compiler-errors): This gives us better spans for bad + // projection types like in issue-50480. + // If the ADT has substs, point to the cause we are given. + // If it does not, then this field probably doesn't normalize + // to begin with, and point to the bad field's span instead. + let cause = if field + .ty(tcx, traits::InternalSubsts::identity_for_item(tcx, adt.did())) + .has_non_region_param() + { + parent_cause.clone() + } else { + ObligationCause::dummy_with_span(span) + }; + match traits::fully_normalize(&infcx, cause, param_env, ty) { + Ok(ty) => { + if !infcx.type_is_copy_modulo_regions(param_env, ty, span) { + infringing.push((field, ty)); + } + } + Err(errors) => { + infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); + } + }; } - if !infringing.is_empty() { - return Err(CopyImplementationError::InfrigingFields(infringing)); - } - if adt.has_dtor(tcx) { - return Err(CopyImplementationError::HasDestructor); - } + } + if !infringing.is_empty() { + return Err(CopyImplementationError::InfrigingFields(infringing)); + } + if adt.has_dtor(tcx) { + return Err(CopyImplementationError::HasDestructor); + } - Ok(()) - }) + Ok(()) } diff --git a/compiler/rustc_trait_selection/src/traits/mod.rs b/compiler/rustc_trait_selection/src/traits/mod.rs index 5153ce11ca0..274a366873c 100644 --- a/compiler/rustc_trait_selection/src/traits/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/mod.rs @@ -234,54 +234,51 @@ fn do_normalize_predicates<'tcx>( // by wfcheck anyway, so I'm not sure we have to check // them here too, and we will remove this function when // we move over to lazy normalization *anyway*. - tcx.infer_ctxt().ignoring_regions().enter(|infcx| { - let predicates = match fully_normalize(&infcx, cause, elaborated_env, predicates) { - Ok(predicates) => predicates, - Err(errors) => { - let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); - return Err(reported); - } - }; + let infcx = tcx.infer_ctxt().ignoring_regions().build(); + let predicates = match fully_normalize(&infcx, cause, elaborated_env, predicates) { + Ok(predicates) => predicates, + Err(errors) => { + let reported = infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); + return Err(reported); + } + }; - debug!("do_normalize_predictes: normalized predicates = {:?}", predicates); + debug!("do_normalize_predictes: normalized predicates = {:?}", predicates); - // We can use the `elaborated_env` here; the region code only - // cares about declarations like `'a: 'b`. - let outlives_env = OutlivesEnvironment::new(elaborated_env); + // We can use the `elaborated_env` here; the region code only + // cares about declarations like `'a: 'b`. + let outlives_env = OutlivesEnvironment::new(elaborated_env); + + // FIXME: It's very weird that we ignore region obligations but apparently + // still need to use `resolve_regions` as we need the resolved regions in + // the normalized predicates. + let errors = infcx.resolve_regions(&outlives_env); + if !errors.is_empty() { + tcx.sess.delay_span_bug( + span, + format!("failed region resolution while normalizing {elaborated_env:?}: {errors:?}"), + ); + } - // FIXME: It's very weird that we ignore region obligations but apparently - // still need to use `resolve_regions` as we need the resolved regions in - // the normalized predicates. - let errors = infcx.resolve_regions(&outlives_env); - if !errors.is_empty() { - tcx.sess.delay_span_bug( + match infcx.fully_resolve(predicates) { + Ok(predicates) => Ok(predicates), + Err(fixup_err) => { + // If we encounter a fixup error, it means that some type + // variable wound up unconstrained. I actually don't know + // if this can happen, and I certainly don't expect it to + // happen often, but if it did happen it probably + // represents a legitimate failure due to some kind of + // unconstrained variable. + // + // @lcnr: Let's still ICE here for now. I want a test case + // for that. + span_bug!( span, - format!( - "failed region resolution while normalizing {elaborated_env:?}: {errors:?}" - ), + "inference variables in normalized parameter environment: {}", + fixup_err ); } - - match infcx.fully_resolve(predicates) { - Ok(predicates) => Ok(predicates), - Err(fixup_err) => { - // If we encounter a fixup error, it means that some type - // variable wound up unconstrained. I actually don't know - // if this can happen, and I certainly don't expect it to - // happen often, but if it did happen it probably - // represents a legitimate failure due to some kind of - // unconstrained variable. - // - // @lcnr: Let's still ICE here for now. I want a test case - // for that. - span_bug!( - span, - "inference variables in normalized parameter environment: {}", - fixup_err - ); - } - } - }) + } } // FIXME: this is gonna need to be removed ... @@ -473,21 +470,20 @@ pub fn impossible_predicates<'tcx>( ) -> bool { debug!("impossible_predicates(predicates={:?})", predicates); - let result = tcx.infer_ctxt().enter(|infcx| { - let param_env = ty::ParamEnv::reveal_all(); - let ocx = ObligationCtxt::new(&infcx); - let predicates = ocx.normalize(ObligationCause::dummy(), param_env, predicates); - for predicate in predicates { - let obligation = Obligation::new(ObligationCause::dummy(), param_env, predicate); - ocx.register_obligation(obligation); - } - let errors = ocx.select_all_or_error(); + let infcx = tcx.infer_ctxt().build(); + let param_env = ty::ParamEnv::reveal_all(); + let ocx = ObligationCtxt::new(&infcx); + let predicates = ocx.normalize(ObligationCause::dummy(), param_env, predicates); + for predicate in predicates { + let obligation = Obligation::new(ObligationCause::dummy(), param_env, predicate); + ocx.register_obligation(obligation); + } + let errors = ocx.select_all_or_error(); - // Clean up after ourselves - let _ = infcx.inner.borrow_mut().opaque_type_storage.take_opaque_types(); + // Clean up after ourselves + let _ = infcx.inner.borrow_mut().opaque_type_storage.take_opaque_types(); - !errors.is_empty() - }); + let result = !errors.is_empty(); debug!("impossible_predicates = {:?}", result); result } @@ -578,18 +574,16 @@ fn is_impossible_method<'tcx>( } }); - tcx.infer_ctxt().ignoring_regions().enter(|ref infcx| { - for obligation in predicates_for_trait { - // Ignore overflow error, to be conservative. - if let Ok(result) = infcx.evaluate_obligation(&obligation) - && !result.may_apply() - { - return true; - } + let infcx = tcx.infer_ctxt().ignoring_regions().build(); + for obligation in predicates_for_trait { + // Ignore overflow error, to be conservative. + if let Ok(result) = infcx.evaluate_obligation(&obligation) + && !result.may_apply() + { + return true; } - - false - }) + } + false } #[derive(Clone, Debug)] @@ -952,10 +946,9 @@ pub fn vtable_trait_upcasting_coercion_new_vptr_slot<'tcx>( }), ); - let implsrc = tcx.infer_ctxt().enter(|infcx| { - let mut selcx = SelectionContext::new(&infcx); - selcx.select(&obligation).unwrap() - }); + let infcx = tcx.infer_ctxt().build(); + let mut selcx = SelectionContext::new(&infcx); + let implsrc = selcx.select(&obligation).unwrap(); let Some(ImplSource::TraitUpcasting(implsrc_traitcasting)) = implsrc else { bug!(); diff --git a/compiler/rustc_trait_selection/src/traits/object_safety.rs b/compiler/rustc_trait_selection/src/traits/object_safety.rs index 8f87a7fdeba..31dd30c5c6a 100644 --- a/compiler/rustc_trait_selection/src/traits/object_safety.rs +++ b/compiler/rustc_trait_selection/src/traits/object_safety.rs @@ -734,10 +734,9 @@ fn receiver_is_dispatchable<'tcx>( Obligation::new(ObligationCause::dummy(), param_env, predicate) }; - tcx.infer_ctxt().enter(|ref infcx| { - // the receiver is dispatchable iff the obligation holds - infcx.predicate_must_hold_modulo_regions(&obligation) - }) + let infcx = tcx.infer_ctxt().build(); + // the receiver is dispatchable iff the obligation holds + infcx.predicate_must_hold_modulo_regions(&obligation) } fn contains_illegal_self_type_reference<'tcx, T: TypeVisitable<'tcx>>( diff --git a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs index bfc3b760050..c891658582a 100644 --- a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs @@ -149,13 +149,9 @@ pub(super) fn specializes(tcx: TyCtxt<'_>, (impl1_def_id, impl2_def_id): (DefId, let impl1_trait_ref = tcx.impl_trait_ref(impl1_def_id).unwrap(); // Create an infcx, taking the predicates of impl1 as assumptions: - tcx.infer_ctxt().enter(|infcx| { - let impl1_trait_ref = match traits::fully_normalize( - &infcx, - ObligationCause::dummy(), - penv, - impl1_trait_ref, - ) { + let infcx = tcx.infer_ctxt().build(); + let impl1_trait_ref = + match traits::fully_normalize(&infcx, ObligationCause::dummy(), penv, impl1_trait_ref) { Ok(impl1_trait_ref) => impl1_trait_ref, Err(_errors) => { tcx.sess.delay_span_bug( @@ -166,9 +162,8 @@ pub(super) fn specializes(tcx: TyCtxt<'_>, (impl1_def_id, impl2_def_id): (DefId, } }; - // Attempt to prove that impl2 applies, given all of the above. - fulfill_implication(&infcx, penv, impl1_trait_ref, impl2_def_id).is_ok() - }) + // Attempt to prove that impl2 applies, given all of the above. + fulfill_implication(&infcx, penv, impl1_trait_ref, impl2_def_id).is_ok() } /// Attempt to fulfill all obligations of `target_impl` after unification with diff --git a/compiler/rustc_trait_selection/src/traits/structural_match.rs b/compiler/rustc_trait_selection/src/traits/structural_match.rs index b6cfff9eb0a..932dbbb81e5 100644 --- a/compiler/rustc_trait_selection/src/traits/structural_match.rs +++ b/compiler/rustc_trait_selection/src/traits/structural_match.rs @@ -265,9 +265,8 @@ impl<'tcx> TypeVisitor<'tcx> for Search<'tcx> { pub fn provide(providers: &mut Providers) { providers.has_structural_eq_impls = |tcx, ty| { - tcx.infer_ctxt().enter(|infcx| { - let cause = ObligationCause::dummy(); - type_marked_structural(&infcx, ty, cause) - }) + let infcx = tcx.infer_ctxt().build(); + let cause = ObligationCause::dummy(); + type_marked_structural(&infcx, ty, cause) }; } |