diff --git a/test/unit/test_TermPrinter.cc b/test/unit/test_TermPrinter.cc
index 9e82da448..546e25b3b 100644
--- a/test/unit/test_TermPrinter.cc
+++ b/test/unit/test_TermPrinter.cc
@@ -13,8 +13,8 @@ class TermPrinterTest : public ::testing::Test {
 
     PTRef buildExampleFormula1() {
         SRef sort = logic.declareUninterpretedSort("U");
-        PTRef x = logic.mkVar(sort, "x");
-        PTRef y = logic.mkVar(sort, "y");
+        PTRef x = logic.mkVar(sort, "?20");
+        PTRef y = logic.mkVar(sort, "????");
         SymRef g_s = logic.declareFun("g", sort, {sort, sort});
         SymRef h_s = logic.declareFun("h", sort, {sort});
         SymRef f_s = logic.declareFun("f", sort, {sort, sort, sort});