diff --git a/tests/msc_vlr/msc_vlr_tests.h b/tests/msc_vlr/msc_vlr_tests.h
index ee26ac4..eaec340 100644
--- a/tests/msc_vlr/msc_vlr_tests.h
+++ b/tests/msc_vlr/msc_vlr_tests.h
@@ -122,7 +122,7 @@
 	int run_test_nr;
 };
 
-typedef void (* msc_vlr_test_func_t )(void);
+typedef void (* msc_vlr_test_func_t )(const char *);
 extern msc_vlr_test_func_t msc_vlr_tests[];
 
 struct msgb *msgb_from_hex(const char *label, uint16_t size, const char *hex);