why it is not working when I use function pointer for macro function as below?

int func(int a, int b)
{
    return a*b;
}

#define multiple1(num) func(1u, num)
#define multiple2(num) func(2u, num)

typedef int (*func_multiple) (int a);

func_multiple func_array[] = {multiple1, multiple2};

I want to know what is wrong here?