diff --git a/menu/menu_event.c b/menu/menu_event.c
index 4d532bdce8..3150189b12 100644
--- a/menu/menu_event.c
+++ b/menu/menu_event.c
@@ -99,7 +99,7 @@ static const char *katakana_page2_grid[] = {
                           "マ","ミ","ム","メ","モ","ン","ッ","ャ","ュ","ョ","⇧",
                           "ヤ","ユ","ヨ","ワ","ヲ","ァ","ィ","ゥ","ェ","ォ","⊕"};
 
-int menu_event_get_osk_ptr()
+int menu_event_get_osk_ptr(void)
 {
    return osk_ptr;
 }
@@ -131,7 +131,7 @@ void menu_event_osk_append(int ptr)
    }
 }
 
-const char** menu_event_get_osk_grid()
+const char** menu_event_get_osk_grid(void)
 {
    return osk_grid;
 }
diff --git a/menu/menu_event.h b/menu/menu_event.h
index a16ce753b8..c083dafb78 100644
--- a/menu/menu_event.h
+++ b/menu/menu_event.h
@@ -39,10 +39,13 @@ void menu_event_keyboard_set(bool down, enum retro_key key);
 
 unsigned char menu_event_keyboard_is_set(enum retro_key key);
 
-int menu_event_get_osk_ptr();
-void menu_event_set_osk_ptr(int);
-void menu_event_osk_append(int);
-const char** menu_event_get_osk_grid();
+int menu_event_get_osk_ptr(void);
+
+void menu_event_set_osk_ptr(int a);
+
+void menu_event_osk_append(int a);
+
+const char** menu_event_get_osk_grid(void);
 
 RETRO_END_DECLS