diff options
Diffstat (limited to 'compiler/rustc_trait_selection/src/traits/coherence.rs')
| -rw-r--r-- | compiler/rustc_trait_selection/src/traits/coherence.rs | 79 |
1 files changed, 38 insertions, 41 deletions
diff --git a/compiler/rustc_trait_selection/src/traits/coherence.rs b/compiler/rustc_trait_selection/src/traits/coherence.rs index 86e7c42376a..59725ce9de0 100644 --- a/compiler/rustc_trait_selection/src/traits/coherence.rs +++ b/compiler/rustc_trait_selection/src/traits/coherence.rs @@ -6,12 +6,9 @@ use crate::infer::outlives::env::OutlivesEnvironment; use crate::infer::InferOk; -use crate::regions::InferCtxtRegionExt; use crate::solve::inspect::{InspectGoal, ProofTreeInferCtxtExt, ProofTreeVisitor}; -use crate::solve::{deeply_normalize_for_diagnostics, inspect, FulfillmentCtxt}; -use crate::traits::engine::TraitEngineExt as _; +use crate::solve::{deeply_normalize_for_diagnostics, inspect}; use crate::traits::select::IntercrateAmbiguityCause; -use crate::traits::structural_normalize::StructurallyNormalizeExt; use crate::traits::NormalizeExt; use crate::traits::SkipLeakCheck; use crate::traits::{ @@ -22,7 +19,7 @@ use rustc_errors::{Diag, EmissionGuarantee}; use rustc_hir::def::DefKind; use rustc_hir::def_id::DefId; use rustc_infer::infer::{DefineOpaqueTypes, InferCtxt, TyCtxtInferExt}; -use rustc_infer::traits::{util, FulfillmentErrorCode, TraitEngine, TraitEngineExt}; +use rustc_infer::traits::{util, FulfillmentErrorCode}; use rustc_middle::traits::query::NoSolution; use rustc_middle::traits::solve::{CandidateSource, Certainty, Goal}; use rustc_middle::traits::specialization_graph::OverlapMode; @@ -35,6 +32,7 @@ use std::fmt::Debug; use std::ops::ControlFlow; use super::error_reporting::suggest_new_overflow_limit; +use super::ObligationCtxt; /// Whether we do the orphan check relative to this crate or to some remote crate. #[derive(Copy, Clone, Debug)] @@ -361,23 +359,27 @@ fn impl_intersection_has_impossible_obligation<'a, 'cx, 'tcx>( let infcx = selcx.infcx; if infcx.next_trait_solver() { - let mut fulfill_cx = FulfillmentCtxt::new(infcx); - fulfill_cx.register_predicate_obligations(infcx, obligations.iter().cloned()); - + let ocx = ObligationCtxt::new(infcx); + ocx.register_obligations(obligations.iter().cloned()); + let errors_and_ambiguities = ocx.select_all_or_error(); // We only care about the obligations that are *definitely* true errors. // Ambiguities do not prove the disjointness of two impls. - let errors = fulfill_cx.select_where_possible(infcx); + let (errors, ambiguities): (Vec<_>, Vec<_>) = + errors_and_ambiguities.into_iter().partition(|error| error.is_true_error()); + if errors.is_empty() { - let overflow_errors = fulfill_cx.collect_remaining_errors(infcx); - let overflowing_predicates = overflow_errors - .into_iter() - .filter(|e| match e.code { - FulfillmentErrorCode::Ambiguity { overflow: Some(true) } => true, - _ => false, - }) - .map(|e| infcx.resolve_vars_if_possible(e.obligation.predicate)) - .collect(); - IntersectionHasImpossibleObligations::No { overflowing_predicates } + IntersectionHasImpossibleObligations::No { + overflowing_predicates: ambiguities + .into_iter() + .filter(|error| { + matches!( + error.code, + FulfillmentErrorCode::Ambiguity { overflow: Some(true) } + ) + }) + .map(|e| infcx.resolve_vars_if_possible(e.obligation.predicate)) + .collect(), + } } else { IntersectionHasImpossibleObligations::Yes } @@ -589,13 +591,14 @@ fn try_prove_negated_where_clause<'tcx>( // Without this, we over-eagerly register coherence ambiguity candidates when // impl candidates do exist. let ref infcx = root_infcx.fork_with_intercrate(false); - let mut fulfill_cx = FulfillmentCtxt::new(infcx); - - fulfill_cx.register_predicate_obligation( - infcx, - Obligation::new(infcx.tcx, ObligationCause::dummy(), param_env, negative_predicate), - ); - if !fulfill_cx.select_all_or_error(infcx).is_empty() { + let ocx = ObligationCtxt::new(infcx); + ocx.register_obligation(Obligation::new( + infcx.tcx, + ObligationCause::dummy(), + param_env, + negative_predicate, + )); + if !ocx.select_all_or_error().is_empty() { return false; } @@ -603,8 +606,7 @@ fn try_prove_negated_where_clause<'tcx>( // if that wasn't implemented just for LocalDefId, and we'd need to do // the normalization ourselves since this is totally fallible... let outlives_env = OutlivesEnvironment::new(param_env); - - let errors = infcx.resolve_regions(&outlives_env); + let errors = ocx.resolve_regions(&outlives_env); if !errors.is_empty() { return false; } @@ -1129,22 +1131,17 @@ impl<'a, 'tcx> ProofTreeVisitor<'tcx> for AmbiguityCausesVisitor<'a, 'tcx> { result: Ok(_), } = cand.kind() { - let lazily_normalize_ty = |ty: Ty<'tcx>| { - let mut fulfill_cx = <dyn TraitEngine<'tcx>>::new(infcx); + let lazily_normalize_ty = |mut ty: Ty<'tcx>| { if matches!(ty.kind(), ty::Alias(..)) { - // FIXME(-Znext-solver=coherence): we currently don't - // normalize opaque types here, resulting in diverging behavior - // for TAITs. - match infcx - .at(&ObligationCause::dummy(), param_env) - .structurally_normalize(ty, &mut *fulfill_cx) - { - Ok(ty) => Ok(ty), - Err(_errs) => Err(()), + let ocx = ObligationCtxt::new(infcx); + ty = ocx + .structurally_normalize(&ObligationCause::dummy(), param_env, ty) + .map_err(|_| ())?; + if !ocx.select_where_possible().is_empty() { + return Err(()); } - } else { - Ok(ty) } + Ok(ty) }; infcx.probe(|_| { |