Question

例如：

#!cpp
#define IS_SET(flag, bit) ((flag) & (bit))
#define SET_BIT(var, bit) ((var) |= (bit))
#define REMOVE_BIT(var, bit) ((var) &= ~(bit))
int f(int a)
{
    int rt=a;
    SET_BIT (rt, 0x4000);
    REMOVE_BIT (rt, 0x200);

    return rt;
};