diff --git a/tests/data_files/Makefile b/tests/data_files/Makefile
index 3d2d5dccd..d1aa3ce65 100644
--- a/tests/data_files/Makefile
+++ b/tests/data_files/Makefile
@@ -1602,3 +1602,5 @@ clean:
 neat: clean
 	rm -f $(all_final)
 .PHONY: clean neat
+
+.INTERMEDIATE: $(all_intermediate)