diff --git a/src/lib/iso_ext.pl b/src/lib/iso_ext.pl
index 7ddc6bb7..378d495a 100644
--- a/src/lib/iso_ext.pl
+++ b/src/lib/iso_ext.pl
@@ -23,11 +23,11 @@
                                type_error/3]).
 
 
-:- meta_predicate call_cleanup(0, 0).
+:- meta_predicate(call_cleanup(0, 0)).
 
-:- meta_predicate setup_call_cleanup(0, 0, 0).
+:- meta_predicate(setup_call_cleanup(0, 0, 0)).
 
-:- meta_predicate forall(0, 0).
+:- meta_predicate(forall(0, 0)).
 
 forall(Generate, Test) :-
     \+ (Generate, \+ Test).
@@ -131,7 +131,7 @@ handle_ile(B, E, _) :-
     '$remove_call_policy_check'(B),
     '$call_with_default_policy'(throw(E)).
 
-:- meta_predicate call_with_inference_limit(0, ?, ?).
+:- meta_predicate(call_with_inference_limit(0, ?, ?)).
 
 call_with_inference_limit(G, L, R) :-
     '$get_current_block'(Bb),