STACK_IRQ_FLAG
[STACK_IRQ_FLAG] = 'f'
slot->slot_type[i] = STACK_IRQ_FLAG;
if (slot->slot_type[i] == STACK_IRQ_FLAG)
if (slot->slot_type[i] != STACK_IRQ_FLAG)
case STACK_IRQ_FLAG:
case STACK_IRQ_FLAG: