diff --git a/daemon/df.c b/daemon/df.c
index ad662fa79..563760d20 100644
--- a/daemon/df.c
+++ b/daemon/df.c
@@ -28,7 +28,7 @@
 #include "actions.h"
 
 char *
-do_df ()
+do_df (void)
 {
   int r;
   char *out, *err;
@@ -49,7 +49,7 @@ do_df ()
 }
 
 char *
-do_df_h ()
+do_df_h (void)
 {
   int r;
   char *out, *err;
diff --git a/daemon/sync.c b/daemon/sync.c
index b353b6c60..e96bf032a 100644
--- a/daemon/sync.c
+++ b/daemon/sync.c
@@ -24,7 +24,7 @@
 #include "actions.h"
 
 int
-do_sync ()
+do_sync (void)
 {
   sync ();
   return 0;