Consolidate OutlivesEnv construction with resolve_regions

compiler/rustc_borrowck/src/region_infer/opaque_types.rs

@@ -439,7 +439,7 @@ impl<'tcx> LazyOpaqueTyEnv<'tcx> {
             tcx.dcx().span_delayed_bug(tcx.def_span(def_id), "error getting implied bounds");
             Default::default()
         });
-        let implied_bounds = infcx.implied_bounds_tys(param_env, parent, &wf_tys);
+        let implied_bounds = infcx.implied_bounds_tys(parent, param_env, wf_tys);
         let outlives_env = OutlivesEnvironment::with_bounds(param_env, implied_bounds);
 
         let mut seen = vec![tcx.lifetimes.re_static];

compiler/rustc_hir_analysis/src/check/check.rs

@@ -27,7 +27,6 @@ use rustc_session::lint::builtin::UNINHABITED_STATIC;
 use rustc_trait_selection::error_reporting::InferCtxtErrorExt;
 use rustc_trait_selection::error_reporting::traits::on_unimplemented::OnUnimplementedDirective;
 use rustc_trait_selection::traits;
-use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt as _;
 use rustc_type_ir::fold::TypeFoldable;
 use tracing::{debug, instrument};
 use ty::TypingMode;
@@ -417,9 +416,7 @@ fn check_opaque_meets_bounds<'tcx>(
     }
 
     let wf_tys = ocx.assumed_wf_types_and_report_errors(param_env, defining_use_anchor)?;
-    let implied_bounds = infcx.implied_bounds_tys(param_env, def_id, &wf_tys);
+    ocx.resolve_regions_and_report_errors(defining_use_anchor, param_env, wf_tys)?;
-    let outlives_env = OutlivesEnvironment::with_bounds(param_env, implied_bounds);
-    ocx.resolve_regions_and_report_errors(defining_use_anchor, &outlives_env)?;
 
     if infcx.next_trait_solver() {
         Ok(())

compiler/rustc_hir_analysis/src/check/compare_impl_item.rs

@@ -9,7 +9,6 @@ use rustc_errors::{Applicability, ErrorGuaranteed, pluralize, struct_span_code_e
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::intravisit::VisitorExt;
 use rustc_hir::{self as hir, AmbigArg, GenericParamKind, ImplItemKind, intravisit};
-use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{self, InferCtxt, TyCtxtInferExt};
 use rustc_infer::traits::util;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
@@ -24,7 +23,6 @@ use rustc_span::Span;
 use rustc_trait_selection::error_reporting::InferCtxtErrorExt;
 use rustc_trait_selection::infer::InferCtxtExt;
 use rustc_trait_selection::regions::InferCtxtRegionExt;
-use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt as _;
 use rustc_trait_selection::traits::{
     self, FulfillmentError, ObligationCause, ObligationCauseCode, ObligationCtxt,
 };
@@ -416,11 +414,7 @@ fn compare_method_predicate_entailment<'tcx>(
 
     // Finally, resolve all regions. This catches wily misuses of
     // lifetime parameters.
-    let outlives_env = OutlivesEnvironment::with_bounds(
+    let errors = infcx.resolve_regions(impl_m_def_id, param_env, wf_tys);
-        param_env,
-        infcx.implied_bounds_tys(param_env, impl_m_def_id, &wf_tys),
-    );
-    let errors = infcx.resolve_regions(&outlives_env);
     if !errors.is_empty() {
         return Err(infcx
             .tainted_by_errors()
@@ -725,11 +719,7 @@ pub(super) fn collect_return_position_impl_trait_in_trait_tys<'tcx>(
 
     // Finally, resolve all regions. This catches wily misuses of
     // lifetime parameters.
-    let outlives_env = OutlivesEnvironment::with_bounds(
+    ocx.resolve_regions_and_report_errors(impl_m_def_id, param_env, wf_tys)?;
-        param_env,
-        infcx.implied_bounds_tys(param_env, impl_m_def_id, &wf_tys),
-    );
-    ocx.resolve_regions_and_report_errors(impl_m_def_id, &outlives_env)?;
 
     let mut remapped_types = DefIdMap::default();
     for (def_id, (ty, args)) in collected_types {
@@ -1883,8 +1873,7 @@ fn compare_const_predicate_entailment<'tcx>(
         return Err(infcx.err_ctxt().report_fulfillment_errors(errors));
     }
 
-    let outlives_env = OutlivesEnvironment::new(param_env);
+    ocx.resolve_regions_and_report_errors(impl_ct_def_id, param_env, [])
-    ocx.resolve_regions_and_report_errors(impl_ct_def_id, &outlives_env)
 }
 
 #[instrument(level = "debug", skip(tcx))]
@@ -2017,8 +2006,7 @@ fn compare_type_predicate_entailment<'tcx>(
 
     // Finally, resolve all regions. This catches wily misuses of
     // lifetime parameters.
-    let outlives_env = OutlivesEnvironment::new(param_env);
+    ocx.resolve_regions_and_report_errors(impl_ty_def_id, param_env, [])
-    ocx.resolve_regions_and_report_errors(impl_ty_def_id, &outlives_env)
 }
 
 /// Validate that `ProjectionCandidate`s created for this associated type will
@@ -2147,9 +2135,7 @@ pub(super) fn check_type_bounds<'tcx>(
 
     // Finally, resolve all regions. This catches wily misuses of
     // lifetime parameters.
-    let implied_bounds = infcx.implied_bounds_tys(param_env, impl_ty_def_id, &assumed_wf_types);
+    ocx.resolve_regions_and_report_errors(impl_ty_def_id, param_env, assumed_wf_types)
-    let outlives_env = OutlivesEnvironment::with_bounds(param_env, implied_bounds);
-    ocx.resolve_regions_and_report_errors(impl_ty_def_id, &outlives_env)
 }
 
 struct ReplaceTy<'tcx> {

compiler/rustc_hir_analysis/src/check/compare_impl_item/refine.rs

@@ -3,7 +3,6 @@ use rustc_data_structures::fx::FxIndexSet;
 use rustc_hir as hir;
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_infer::infer::TyCtxtInferExt;
-use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_lint_defs::builtin::{REFINING_IMPL_TRAIT_INTERNAL, REFINING_IMPL_TRAIT_REACHABLE};
 use rustc_middle::span_bug;
 use rustc_middle::traits::ObligationCause;
@@ -13,7 +12,6 @@ use rustc_middle::ty::{
 };
 use rustc_span::Span;
 use rustc_trait_selection::regions::InferCtxtRegionExt;
-use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt;
 use rustc_trait_selection::traits::{ObligationCtxt, elaborate, normalize_param_env_or_error};
 
 /// Check that an implementation does not refine an RPITIT from a trait method signature.
@@ -170,11 +168,7 @@ pub(crate) fn check_refining_return_position_impl_trait_in_trait<'tcx>(
         tcx.dcx().delayed_bug("encountered errors when checking RPITIT refinement (selection)");
         return;
     }
-    let outlives_env = OutlivesEnvironment::with_bounds(
+    let errors = infcx.resolve_regions(impl_m.def_id.expect_local(), param_env, implied_wf_types);
-        param_env,
-        infcx.implied_bounds_tys(param_env, impl_m.def_id.expect_local(), &implied_wf_types),
-    );
-    let errors = infcx.resolve_regions(&outlives_env);
     if !errors.is_empty() {
         tcx.dcx().delayed_bug("encountered errors when checking RPITIT refinement (regions)");
         return;

compiler/rustc_hir_analysis/src/check/dropck.rs

@@ -5,7 +5,6 @@
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::codes::*;
 use rustc_errors::{ErrorGuaranteed, struct_span_code_err};
-use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{RegionResolutionError, TyCtxtInferExt};
 use rustc_infer::traits::{ObligationCause, ObligationCauseCode};
 use rustc_middle::ty::util::CheckRegions;
@@ -192,7 +191,7 @@ fn ensure_drop_predicates_are_implied_by_item_defn<'tcx>(
         return Err(guar.unwrap());
     }
 
-    let errors = ocx.infcx.resolve_regions(&OutlivesEnvironment::new(adt_env));
+    let errors = ocx.infcx.resolve_regions(adt_def_id, adt_env, []);
     if !errors.is_empty() {
         let mut guar = None;
         for error in errors {

compiler/rustc_hir_analysis/src/check/mod.rs

@@ -80,7 +80,6 @@ use rustc_errors::{Diag, ErrorGuaranteed, pluralize, struct_span_code_err};
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::intravisit::Visitor;
 use rustc_index::bit_set::DenseBitSet;
-use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{self, TyCtxtInferExt as _};
 use rustc_infer::traits::ObligationCause;
 use rustc_middle::query::Providers;
@@ -655,8 +654,7 @@ pub fn check_function_signature<'tcx>(
         }
     }
 
-    let outlives_env = OutlivesEnvironment::new(param_env);
+    if let Err(e) = ocx.resolve_regions_and_report_errors(local_id, param_env, []) {
-    if let Err(e) = ocx.resolve_regions_and_report_errors(local_id, &outlives_env) {
         return Err(e);
     }
 

compiler/rustc_hir_analysis/src/check/wfcheck.rs

@@ -128,13 +128,17 @@ where
     let infcx_compat = infcx.fork();
 
     // We specifically want to call the non-compat version of `implied_bounds_tys`; we do this always.
-    let implied_bounds =
+    let implied_bounds = infcx.implied_bounds_tys_compat(
-        infcx.implied_bounds_tys_compat(param_env, body_def_id, &assumed_wf_types, false);
+        body_def_id,
+        param_env,
+        assumed_wf_types.iter().copied(),
+        false,
+    );
     let outlives_env = OutlivesEnvironment::with_bounds(param_env, implied_bounds);
 
     lint_redundant_lifetimes(tcx, body_def_id, &outlives_env);
 
-    let errors = infcx.resolve_regions(&outlives_env);
+    let errors = infcx.resolve_regions_with_outlives_env(&outlives_env);
     if errors.is_empty() {
         return Ok(());
     }
@@ -173,9 +177,9 @@ where
     // just obscures what we mean here anyways. Let's just be explicit.
     if is_bevy && !infcx.tcx.sess.opts.unstable_opts.no_implied_bounds_compat {
         let implied_bounds =
-            infcx_compat.implied_bounds_tys_compat(param_env, body_def_id, &assumed_wf_types, true);
+            infcx_compat.implied_bounds_tys_compat(body_def_id, param_env, assumed_wf_types, true);
         let outlives_env = OutlivesEnvironment::with_bounds(param_env, implied_bounds);
-        let errors_compat = infcx_compat.resolve_regions(&outlives_env);
+        let errors_compat = infcx_compat.resolve_regions_with_outlives_env(&outlives_env);
         if errors_compat.is_empty() {
             Ok(())
         } else {
@@ -769,12 +773,7 @@ fn test_region_obligations<'tcx>(
 
     add_constraints(&infcx);
 
-    let outlives_environment = OutlivesEnvironment::with_bounds(
+    let errors = infcx.resolve_regions(id, param_env, wf_tys.iter().copied());
-        param_env,
-        infcx.implied_bounds_tys(param_env, id, wf_tys),
-    );
-
-    let errors = infcx.resolve_regions(&outlives_environment);
     debug!(?errors, "errors");
 
     // If we were able to prove that the type outlives the region without

compiler/rustc_hir_analysis/src/coherence/builtin.rs

@@ -10,7 +10,6 @@ use rustc_hir as hir;
 use rustc_hir::ItemKind;
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::lang_items::LangItem;
-use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{self, RegionResolutionError, TyCtxtInferExt};
 use rustc_infer::traits::Obligation;
 use rustc_middle::ty::adjustment::CoerceUnsizedInfo;
@@ -346,8 +345,7 @@ fn visit_implementation_of_dispatch_from_dyn(checker: &Checker<'_>) -> Result<()
                 }
 
                 // Finally, resolve all regions.
-                let outlives_env = OutlivesEnvironment::new(param_env);
+                res = res.and(ocx.resolve_regions_and_report_errors(impl_did, param_env, []));
-                res = res.and(ocx.resolve_regions_and_report_errors(impl_did, &outlives_env));
             }
             res
         }
@@ -564,8 +562,7 @@ pub(crate) fn coerce_unsized_info<'tcx>(
     }
 
     // Finally, resolve all regions.
-    let outlives_env = OutlivesEnvironment::new(param_env);
+    let _ = ocx.resolve_regions_and_report_errors(impl_did, param_env, []);
-    let _ = ocx.resolve_regions_and_report_errors(impl_did, &outlives_env);
 
     Ok(CoerceUnsizedInfo { custom_kind: kind })
 }

compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs

@@ -68,7 +68,6 @@
 use rustc_data_structures::fx::FxHashSet;
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_infer::infer::TyCtxtInferExt;
-use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::traits::ObligationCause;
 use rustc_infer::traits::specialization_graph::Node;
 use rustc_middle::ty::trait_def::TraitSpecializationKind;
@@ -77,7 +76,6 @@ use rustc_middle::ty::{
 };
 use rustc_span::{ErrorGuaranteed, Span};
 use rustc_trait_selection::error_reporting::InferCtxtErrorExt;
-use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt as _;
 use rustc_trait_selection::traits::{self, ObligationCtxt, translate_args_with_cause, wf};
 use tracing::{debug, instrument};
 
@@ -176,7 +174,6 @@ fn get_impl_args(
     let ocx = ObligationCtxt::new_with_diagnostics(infcx);
     let param_env = tcx.param_env(impl1_def_id);
     let impl1_span = tcx.def_span(impl1_def_id);
-    let assumed_wf_types = ocx.assumed_wf_types_and_report_errors(param_env, impl1_def_id)?;
 
     let impl1_args = GenericArgs::identity_for_item(tcx, impl1_def_id);
     let impl2_args = translate_args_with_cause(
@@ -194,9 +191,8 @@ fn get_impl_args(
         return Err(guar);
     }
 
-    let implied_bounds = infcx.implied_bounds_tys(param_env, impl1_def_id, &assumed_wf_types);
+    let assumed_wf_types = ocx.assumed_wf_types_and_report_errors(param_env, impl1_def_id)?;
-    let outlives_env = OutlivesEnvironment::with_bounds(param_env, implied_bounds);
+    let _ = ocx.resolve_regions_and_report_errors(impl1_def_id, param_env, assumed_wf_types);
-    let _ = ocx.resolve_regions_and_report_errors(impl1_def_id, &outlives_env);
     let Ok(impl2_args) = infcx.fully_resolve(impl2_args) else {
         let span = tcx.def_span(impl1_def_id);
         let guar = tcx.dcx().emit_err(GenericArgsOnOverriddenImpl { span });

compiler/rustc_lint/src/impl_trait_overcaptures.rs

@@ -191,7 +191,7 @@ fn check_fn(tcx: TyCtxt<'_>, parent_def_id: LocalDefId) {
             let ocx = ObligationCtxt::new(&infcx);
             let assumed_wf_tys = ocx.assumed_wf_types(param_env, parent_def_id).unwrap_or_default();
             let implied_bounds =
-                infcx.implied_bounds_tys_compat(param_env, parent_def_id, &assumed_wf_tys, false);
+                infcx.implied_bounds_tys_compat(parent_def_id, param_env, assumed_wf_tys, false);
             OutlivesEnvironment::with_bounds(param_env, implied_bounds)
         }),
     });

compiler/rustc_trait_selection/src/regions.rs

@@ -1,10 +1,13 @@
+use rustc_hir::def_id::LocalDefId;
 use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{InferCtxt, RegionResolutionError};
 use rustc_macros::extension;
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::traits::query::NoSolution;
+use rustc_middle::ty::{self, Ty};
 
 use crate::traits::ScrubbedTraitError;
+use crate::traits::outlives_bounds::InferCtxtExt;
 
 #[extension(pub trait InferCtxtRegionExt<'tcx>)]
 impl<'tcx> InferCtxt<'tcx> {
@@ -15,10 +18,23 @@ impl<'tcx> InferCtxt<'tcx> {
     /// Prefer this method over `resolve_regions_with_normalize`, unless you are
     /// doing something specific for normalization.
     fn resolve_regions(
+        &self,
+        body_id: LocalDefId,
+        param_env: ty::ParamEnv<'tcx>,
+        assumed_wf_tys: impl IntoIterator<Item = Ty<'tcx>>,
+    ) -> Vec<RegionResolutionError<'tcx>> {
+        self.resolve_regions_with_outlives_env(&OutlivesEnvironment::with_bounds(
+            param_env,
+            self.implied_bounds_tys(body_id, param_env, assumed_wf_tys),
+        ))
+    }
+
+    /// Don't call this directly unless you know what you're doing.
+    fn resolve_regions_with_outlives_env(
         &self,
         outlives_env: &OutlivesEnvironment<'tcx>,
     ) -> Vec<RegionResolutionError<'tcx>> {
-        self.resolve_regions_with_normalize(outlives_env, |ty, origin| {
+        self.resolve_regions_with_normalize(&outlives_env, |ty, origin| {
             let ty = self.resolve_vars_if_possible(ty);
 
             if self.next_trait_solver() {

compiler/rustc_trait_selection/src/traits/coherence.rs

@@ -9,7 +9,7 @@ use std::fmt::Debug;
 use rustc_data_structures::fx::{FxHashSet, FxIndexSet};
 use rustc_errors::{Diag, EmissionGuarantee};
 use rustc_hir::def::DefKind;
-use rustc_hir::def_id::DefId;
+use rustc_hir::def_id::{CRATE_DEF_ID, DefId};
 use rustc_infer::infer::{DefineOpaqueTypes, InferCtxt, TyCtxtInferExt};
 use rustc_infer::traits::PredicateObligations;
 use rustc_middle::bug;
@@ -27,7 +27,6 @@ use tracing::{debug, instrument, warn};
 use super::ObligationCtxt;
 use crate::error_reporting::traits::suggest_new_overflow_limit;
 use crate::infer::InferOk;
-use crate::infer::outlives::env::OutlivesEnvironment;
 use crate::solve::inspect::{InspectGoal, ProofTreeInferCtxtExt, ProofTreeVisitor};
 use crate::solve::{SolverDelegate, deeply_normalize_for_diagnostics, inspect};
 use crate::traits::query::evaluate_obligation::InferCtxtExt;
@@ -596,8 +595,7 @@ fn try_prove_negated_where_clause<'tcx>(
     // FIXME: We could use the assumed_wf_types from both impls, I think,
     // 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 = ocx.resolve_regions(CRATE_DEF_ID, param_env, []);
-    let errors = ocx.resolve_regions(&outlives_env);
     if !errors.is_empty() {
         return false;
     }

compiler/rustc_trait_selection/src/traits/engine.rs

@@ -8,7 +8,6 @@ use rustc_infer::infer::at::ToTrace;
 use rustc_infer::infer::canonical::{
     Canonical, CanonicalQueryResponse, CanonicalVarValues, QueryResponse,
 };
-use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{DefineOpaqueTypes, InferCtxt, InferOk, RegionResolutionError, TypeTrace};
 use rustc_infer::traits::PredicateObligations;
 use rustc_macros::extension;
@@ -217,14 +216,15 @@ where
     /// will result in region constraints getting ignored.
     pub fn resolve_regions_and_report_errors(
         self,
-        generic_param_scope: LocalDefId,
+        body_id: LocalDefId,
-        outlives_env: &OutlivesEnvironment<'tcx>,
+        param_env: ty::ParamEnv<'tcx>,
+        assumed_wf_tys: impl IntoIterator<Item = Ty<'tcx>>,
     ) -> Result<(), ErrorGuaranteed> {
-        let errors = self.infcx.resolve_regions(outlives_env);
+        let errors = self.infcx.resolve_regions(body_id, param_env, assumed_wf_tys);
         if errors.is_empty() {
             Ok(())
         } else {
-            Err(self.infcx.err_ctxt().report_region_errors(generic_param_scope, &errors))
+            Err(self.infcx.err_ctxt().report_region_errors(body_id, &errors))
         }
     }
 
@@ -235,9 +235,11 @@ where
     #[must_use]
     pub fn resolve_regions(
         self,
-        outlives_env: &OutlivesEnvironment<'tcx>,
+        body_id: LocalDefId,
+        param_env: ty::ParamEnv<'tcx>,
+        assumed_wf_tys: impl IntoIterator<Item = Ty<'tcx>>,
     ) -> Vec<RegionResolutionError<'tcx>> {
-        self.infcx.resolve_regions(outlives_env)
+        self.infcx.resolve_regions(body_id, param_env, assumed_wf_tys)
     }
 }
 

compiler/rustc_trait_selection/src/traits/misc.rs

@@ -4,13 +4,10 @@ use std::assert_matches::assert_matches;
 
 use hir::LangItem;
 use rustc_ast::Mutability;
-use rustc_data_structures::fx::FxIndexSet;
 use rustc_hir as hir;
-use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{RegionResolutionError, TyCtxtInferExt};
 use rustc_middle::ty::{self, AdtDef, Ty, TyCtxt, TypeVisitableExt, TypingMode};
 
-use super::outlives_bounds::InferCtxtExt;
 use crate::regions::InferCtxtRegionExt;
 use crate::traits::{self, FulfillmentError, ObligationCause};
 
@@ -170,15 +167,7 @@ pub fn type_allowed_to_implement_const_param_ty<'tcx>(
         }
 
         // Check regions assuming the self type of the impl is WF
-        let outlives_env = OutlivesEnvironment::with_bounds(
+        let errors = infcx.resolve_regions(parent_cause.body_id, param_env, [self_type]);
-            param_env,
-            infcx.implied_bounds_tys(
-                param_env,
-                parent_cause.body_id,
-                &FxIndexSet::from_iter([self_type]),
-            ),
-        );
-        let errors = infcx.resolve_regions(&outlives_env);
         if !errors.is_empty() {
             infringing_inner_tys.push((inner_ty, InfringingFieldsReason::Regions(errors)));
             continue;
@@ -261,15 +250,7 @@ pub fn all_fields_implement_trait<'tcx>(
             }
 
             // Check regions assuming the self type of the impl is WF
-            let outlives_env = OutlivesEnvironment::with_bounds(
+            let errors = infcx.resolve_regions(parent_cause.body_id, param_env, [self_type]);
-                param_env,
-                infcx.implied_bounds_tys(
-                    param_env,
-                    parent_cause.body_id,
-                    &FxIndexSet::from_iter([self_type]),
-                ),
-            );
-            let errors = infcx.resolve_regions(&outlives_env);
             if !errors.is_empty() {
                 infringing.push((field, ty, InfringingFieldsReason::Regions(errors)));
             }

compiler/rustc_trait_selection/src/traits/mod.rs

@@ -290,12 +290,10 @@ fn do_normalize_predicates<'tcx>(
 
     // 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);
+    let errors = infcx.resolve_regions(cause.body_id, elaborated_env, []);
     if !errors.is_empty() {
         tcx.dcx().span_delayed_bug(
             span,

compiler/rustc_trait_selection/src/traits/outlives_bounds.rs

@@ -1,4 +1,3 @@
-use rustc_data_structures::fx::FxIndexSet;
 use rustc_infer::infer::InferOk;
 use rustc_infer::infer::resolve::OpportunisticRegionResolver;
 use rustc_infer::traits::query::type_op::ImpliedOutlivesBounds;
@@ -12,9 +11,6 @@ use tracing::instrument;
 use crate::infer::InferCtxt;
 use crate::traits::{ObligationCause, ObligationCtxt};
 
-pub type BoundsCompat<'a, 'tcx: 'a> = impl Iterator<Item = OutlivesBound<'tcx>> + 'a;
-pub type Bounds<'a, 'tcx: 'a> = impl Iterator<Item = OutlivesBound<'tcx>> + 'a;
-
 /// Implied bounds are region relationships that we deduce
 /// automatically. The idea is that (e.g.) a caller must check that a
 /// function's argument types are well-formed immediately before
@@ -110,36 +106,33 @@ fn implied_outlives_bounds<'a, 'tcx>(
     bounds
 }
 
-#[extension(pub trait InferCtxtExt<'a, 'tcx>)]
+#[extension(pub trait InferCtxtExt<'tcx>)]
-impl<'a, 'tcx: 'a> InferCtxt<'tcx> {
+impl<'tcx> InferCtxt<'tcx> {
     /// Do *NOT* call this directly.
-    fn implied_bounds_tys_compat(
+    fn implied_bounds_tys_compat<Tys: IntoIterator<Item = Ty<'tcx>>>(
-        &'a self,
+        &self,
-        param_env: ParamEnv<'tcx>,
         body_id: LocalDefId,
-        tys: &'a FxIndexSet<Ty<'tcx>>,
+        param_env: ParamEnv<'tcx>,
+        tys: Tys,
         compat: bool,
-    ) -> BoundsCompat<'a, 'tcx> {
+    ) -> impl Iterator<Item = OutlivesBound<'tcx>> {
-        tys.iter()
+        tys.into_iter()
-            .flat_map(move |ty| implied_outlives_bounds(self, param_env, body_id, *ty, compat))
+            .flat_map(move |ty| implied_outlives_bounds(self, param_env, body_id, ty, compat))
     }
 
     /// If `-Z no-implied-bounds-compat` is set, calls `implied_bounds_tys_compat`
     /// with `compat` set to `true`, otherwise `false`.
     fn implied_bounds_tys(
-        &'a self,
+        &self,
-        param_env: ParamEnv<'tcx>,
         body_id: LocalDefId,
-        tys: &'a FxIndexSet<Ty<'tcx>>,
+        param_env: ParamEnv<'tcx>,
-    ) -> Bounds<'a, 'tcx> {
+        tys: impl IntoIterator<Item = Ty<'tcx>>,
-        tys.iter().flat_map(move |ty| {
+    ) -> impl Iterator<Item = OutlivesBound<'tcx>> {
-            implied_outlives_bounds(
+        self.implied_bounds_tys_compat(
-                self,
+            body_id,
-                param_env,
+            param_env,
-                body_id,
+            tys,
-                *ty,
+            !self.tcx.sess.opts.unstable_opts.no_implied_bounds_compat,
-                !self.tcx.sess.opts.unstable_opts.no_implied_bounds_compat,
+        )
-            )
-        })
     }
 }