diff --git a/src/emu/hashfile.c b/src/emu/hashfile.c
index f5b6561652c..f80b21158d8 100644
--- a/src/emu/hashfile.c
+++ b/src/emu/hashfile.c
@@ -576,21 +576,25 @@ const char *hashfile_extrainfo(device_image_interface &image)
 	/* now read the hash file */
 	image.crc();
 	extra_info = NULL;
-	int compat, drv = driver_list::find(image.device().machine().system());
+	int drv = driver_list::find(image.device().machine().system());
+	int compat, open = drv;
 	do
 	{
-		rc = read_hash_config(image, driver_list::driver(drv).name);
+		rc = read_hash_config(image, driver_list::driver(open).name);
 		// first check if there are compatible systems
-		compat = driver_list::compatible_with(drv);
+		compat = driver_list::compatible_with(open);
 		// if so, try to open its hashfile
 		if (compat != -1)
-			drv = compat;
+			open = compat;
 		// otherwise, try with the parent
 		else
+		{
 			drv = driver_list::clone(drv);
+			open = drv;
+		}
 	}
 	// if no extrainfo has been found but we can try a compatible or a parent set, go back
-	while (rc == NULL && drv != -1);
+	while (rc == NULL && open != -1);
 	return rc;
 }