diff --git a/src/testdir/Make_os2.mak b/src/testdir/Make_os2.mak
index 0b3ce26..bab000d 100644
--- a/src/testdir/Make_os2.mak
+++ b/src/testdir/Make_os2.mak
@@ -49,6 +49,7 @@
 		test_listlbr.out \
 		test_listlbr_utf8.out \
 		test_mapping.out \
+		test_marks.out \
 		test_nested_function.out \
 		test_options.out \
 		test_qf_title.out \