static void outb(unsigned char value, unsigned short port) { __builtin_outb(value, port); } static void uart_init(void) { int a; if (1 == 1) { a = 1; outb(a, 0x3f8); } else { a = 2; outb(a, 0x3f8); } outb(a, 0x3f8); } static void main(void) { uart_init(); }