{"ast_node_type":"other","tokens":[{"end":50,"kind":"keyword","start":0,"text":"debug_assert!(!infcx.next_trait_solver());"}]}
        debug_assert!(!infcx.next_trait_solver());
        let infcx = self.type_checker.infcx;
        // `handle_opaque_type` cannot handle subtyping, so to support subtyping