Update compiler/rustc_trait_selection/src/traits/outlives_bounds.rs

Author: aliemjay

compiler/rustc_trait_selection/src/traits/outlives_bounds.rs

@@ -56,8 +56,9 @@ impl<'a, 'tcx: 'a> InferCtxtExt<'a, 'tcx> for InferCtxt<'tcx> {
         let ty = self.resolve_vars_if_possible(ty);
         let ty = OpportunisticRegionResolver::new(self).fold_ty(ty);
 
-        // We must avoid processing unconstrained lifetime variables in implied
-        // bounds. See #110161 for context.
+        // We do not expect existential variables in implied bounds.
+        // We may however encounter unconstrained lifetime variables in invalid
+        // code. See #110161 for context.
         assert!(!ty.has_non_region_infer());
         if ty.needs_infer() {
             self.tcx.sess.delay_span_bug(