diff --git a/include/functions.h b/include/functions.h
index c86b2b444e..f89f7241c5 100644
--- a/include/functions.h
+++ b/include/functions.h
@@ -2263,7 +2263,7 @@ void func_800F574C(f32 arg0, UNK_TYPE arg2);
 void func_800F595C(u16);
 void func_800F59E8(u16);
 void func_800F5ACC(u32 bgmID);
-void func_800F5B58();
+void func_800F5B58(void);
 void func_800F5C64(u16);
 // ? func_800F5CF8(?);
 // ? func_800F5E18(?);