diff --git a/pl/arith.yap b/pl/arith.yap
index 8e0aec8c5..4dba7616c 100644
--- a/pl/arith.yap
+++ b/pl/arith.yap
@@ -406,9 +406,9 @@ expand_expr(Op, X, Y, O, Q, P) :-
 '$contains_illegal_dcgnt'(NT) :-
     functor(NT, _, A),
     between(1, A, I),
-    arg(I, NT),
-    nonvar(I),
-    ( I = ! ; I = phrase(_,_,_) ), !.
+    arg(I, NT, AI),
+    nonvar(AI),
+    ( AI = ! ; AI = phrase(_,_,_) ), !.
 %	write(contains_illegal_nt(NT)),		% JW: we do not want to write
 %	nl.
 
diff --git a/pl/modules.yap b/pl/modules.yap
index c055fee00..33f50fda4 100644
--- a/pl/modules.yap
+++ b/pl/modules.yap
@@ -960,7 +960,7 @@ meta_predicate declaration
 
 '$meta_expansion0'(G, _HM, _BM, SM, SM:G, _HVars) :-
     var(G), !.
-'$meta_expansion0'(M:G, _HM, _BM, SM, G1, _HVars) :-
+'$meta_expansion0'(M:G, _HM, _BM, _SM, G1, _HVars) :-
     var(M), !,
     G1 = '$execute_wo_mod'(G,M).
 % support for all/3
@@ -1006,7 +1006,7 @@ its parent goal.
 
 '$is_mt'(M, H, CM, B, (context_module(CM),B)) :-
 	'$module_transparent'(_, M, _, H), !.
-'$is_mt'(_M, _H, CM, B, B).
+'$is_mt'(_M, _H, _CM, B, B).
 
 % comma has its own problems.
 :- '$install_meta_predicate'(','(0,0), prolog).