Until C23, you could declare a pointer to a procedure that takes an unspecified amount of any type arguments like this

    void foo( int (*f)() )
    {
        f(1);
        f(1, "2" , 3.0);
    }

If you compile with -std=c23, both gcc and clang will throw an error ( (*f)() is now the same as (*f)(void) )