Dejargnonize subst

compiler/rustc_trait_selection/src/traits/query/type_op/ascribe_user_type.rs

@@ -116,7 +116,7 @@ fn relate_mir_and_user_args<'tcx>(
         ocx.register_obligation(Obligation::new(tcx, cause, param_env, instantiated_predicate));
     }
 
-    // Now prove the well-formedness of `def_id` with `substs`.
+    // Now prove the well-formedness of `def_id` with `args`.
     // Note for some items, proving the WF of `ty` is not sufficient because the
     // well-formedness of an item may depend on the WF of gneneric args not present in the
     // item's type. Currently this is true for associated consts, e.g.:

compiler/rustc_trait_selection/src/traits/query/type_op/implied_outlives_bounds.rs

@@ -170,7 +170,7 @@ pub fn compute_implied_outlives_bounds_compat_inner<'tcx>(
         }
 
         // Compute the obligations for `arg` to be well-formed. If `arg` is
-        // an unresolved inference variable, just substituted an empty set
+        // an unresolved inference variable, just instantiated an empty set
         // -- because the return type here is going to be things we *add*
         // to the environment, it's always ok for this set to be smaller
         // than the ultimate set. (Note: normally there won't be