diff --git a/src/memfile_test.c b/src/memfile_test.c
index 672d30f..3fc1351 100644
--- a/src/memfile_test.c
+++ b/src/memfile_test.c
@@ -31,7 +31,7 @@
  * Test mf_hash_*() functions.
  */
     static void
-test_mf_hash()
+test_mf_hash(void)
 {
     mf_hashtab_T   ht;
     mf_hashitem_T  *item;
@@ -138,7 +138,7 @@
 }
 
     int
-main()
+main(void)
 {
     test_mf_hash();
     return 0;