diff --git a/test_regress/driver.pl b/test_regress/driver.pl
index 1d967ba8c..6edcc3ed8 100755
--- a/test_regress/driver.pl
+++ b/test_regress/driver.pl
@@ -277,7 +277,7 @@ sub _calc_hashset {
             local $/;
             unpack("%32W*", $t);
         };
-        if ($set == ($checksum % $nsets)) {
+        if (($set % $nsets) == ($checksum % $nsets)) {
             push @new, $t;
         }
     }