diff --git a/src/smt/theory_str.cpp b/src/smt/theory_str.cpp
index aa0ee21675b..823cb382471 100644
--- a/src/smt/theory_str.cpp
+++ b/src/smt/theory_str.cpp
@@ -8417,7 +8417,7 @@ namespace smt {
                     TRACE("str", tout << "found string-integer conversion term: " << mk_pp(ex, get_manager()) << std::endl;);
                     string_int_conversion_terms.push_back(ap);
                     m_library_aware_axiom_todo.push_back(n);
-                } else if (ap->get_num_args() == 0 && !u.str.is_string(ap)) {
+                } else if (/*ap->get_num_args() == 0 &&*/ !u.str.is_string(ap)) {
                     // if ex is a variable, add it to our list of variables
                     TRACE("str", tout << "tracking variable " << mk_ismt2_pp(ap, get_manager()) << std::endl;);
                     variable_set.insert(ex);