use type alias impl trait in `outlives_bounds::InferCtxtExt`

compiler/rustc_mir_dataflow/src/framework/mod.rs

@@ -256,6 +256,7 @@ pub trait Analysis<'tcx>: AnalysisDomain<'tcx> {
     ///     .iterate_to_fixpoint()
     ///     .into_results_cursor(body);
     /// ```
+    #[inline]
     fn into_engine<'mir>(
         self,
         tcx: TyCtxt<'tcx>,
@@ -413,7 +414,7 @@ where
     }
 
     /* Extension methods */
-
+    #[inline]
     fn into_engine<'mir>(
         self,
         tcx: TyCtxt<'tcx>,

compiler/rustc_typeck/src/check/wfcheck.rs

@@ -699,7 +699,7 @@ fn resolve_regions_with_wf_tys<'tcx>(
         let outlives_environment = OutlivesEnvironment::with_bounds(
             param_env,
             Some(&infcx),
-            infcx.implied_bounds_tys(param_env, id, wf_tys.iter().map(|ty| *ty)),
+            infcx.implied_bounds_tys(param_env, id, wf_tys.clone()),
         );
         let region_bound_pairs = outlives_environment.region_bound_pairs();
 

compiler/rustc_typeck/src/impl_wf_check/min_specialization.rs

@@ -158,6 +158,16 @@ fn get_impl_substs<'tcx>(
 
 
 
+
+
+
+
+
+
+
+
+
+
         let errors = ocx.select_all_or_error();
         if !errors.is_empty() {
             ocx.infcx.report_fulfillment_errors(&errors, None, false);

compiler/rustc_typeck/src/lib.rs

@@ -72,6 +72,7 @@ This API is completely unstable and subject to change.
 #![feature(slice_partition_dedup)]
 #![feature(try_blocks)]
 #![feature(is_some_with)]
+#![feature(type_alias_impl_trait)]
 #![recursion_limit = "256"]
 
 #[macro_use]

compiler/rustc_typeck/src/outlives/outlives_bounds.rs

@@ -1,3 +1,4 @@
+use rustc_data_structures::fx::FxHashSet;
 use rustc_hir as hir;
 use rustc_hir::HirId;
 use rustc_middle::ty::{self, ParamEnv, Ty};
@@ -8,6 +9,7 @@ use rustc_trait_selection::traits::{ObligationCause, TraitEngine, TraitEngineExt
 
 pub use rustc_middle::traits::query::OutlivesBound;
 
+type Bounds<'a, 'tcx: 'a> = impl Iterator<Item = OutlivesBound<'tcx>> + 'a;
 pub trait InferCtxtExt<'a, 'tcx> {
     fn implied_outlives_bounds(
         &self,
@@ -20,8 +22,8 @@ pub trait InferCtxtExt<'a, 'tcx> {
         &'a self,
         param_env: ty::ParamEnv<'tcx>,
         body_id: hir::HirId,
-        tys: impl IntoIterator<Item = Ty<'tcx>> + 'a,
-    ) -> Box<dyn Iterator<Item = OutlivesBound<'tcx>> + 'a>;
+        tys: FxHashSet<Ty<'tcx>>,
+    ) -> Bounds<'a, 'tcx>;
 }
 
 impl<'a, 'cx, 'tcx: 'a> InferCtxtExt<'a, 'tcx> for InferCtxt<'cx, 'tcx> {
@@ -100,15 +102,13 @@ impl<'a, 'cx, 'tcx: 'a> InferCtxtExt<'a, 'tcx> for InferCtxt<'cx, 'tcx> {
         &'a self,
         param_env: ParamEnv<'tcx>,
         body_id: HirId,
-        tys: impl IntoIterator<Item = Ty<'tcx>> + 'a,
-    ) -> Box<dyn Iterator<Item = OutlivesBound<'tcx>> + 'a> {
-        Box::new(
-            tys.into_iter()
-                .map(move |ty| {
-                    let ty = self.resolve_vars_if_possible(ty);
-                    self.implied_outlives_bounds(param_env, body_id, ty)
-                })
-                .flatten(),
-        )
+        tys: FxHashSet<Ty<'tcx>>,
+    ) -> Bounds<'a, 'tcx> {
+        tys.into_iter()
+            .map(move |ty| {
+                let ty = self.resolve_vars_if_possible(ty);
+                self.implied_outlives_bounds(param_env, body_id, ty)
+            })
+            .flatten()
     }
 }