先定义一个简单的结构：
typedef struct stu
{
char name[10];
int ID;
int score;
}stu;

函数返回引用
stu &fun(stu &student)
{
stu stu1;
stu1 = student;
return stu1;
}

int main()
{
stu student1 = {"name", 10101, 100};
stu &student2 = fun(student1);
cout << "score: " << student2.score << endl;
cout << "ID: " << student2.ID << endl;
cout << "name: " << student2.name << endl;
system("pause");
return 1;
}
运行后如图, 为什么出错？:

stu &fun(stu &student)
{
stu stu1;
stu1 = student;
return stu1;
}

int main()
{
stu student1 = {"name", 10101, 100};

stu student2 = fun(student1);

cout << "score: " << student2.score << endl;
cout << "ID: " << student2.ID << endl;
cout << "name: " << student2.name << endl;

//delete &student2;
//&student2 = NULL;
system("pause");
return 1;
}
运行后如图, 为什么正确？:

请woodhead兄台明示。。。:)

Kai, 在copy这个动作上，系统应该是给这个拷贝分配了空间的，那么这个存储空间的生存期如何？是从哪个内存块中分配出来的？