c++ string memcpy

//----------------------------------------------------

//AUTHOR: lanyang123456

//DATE: 2014-10-30

//---------------------------------------------------

/*
str5.cpp
$ g++ -o test str5.cpp
OS Ubuntu
*/

#include <string>
#include <iostream>

#include <string.h>
#include <stdio.h>

using namespace std;

int main()
{
string t1("123456789");
string t2;

cout<<"t1 string:"<<t1<<endl;
printf("t1 string:%s ",t1.c_str());//返回一个以null终止的c字符串
printf("sizeof t1 = %lu ", sizeof(t1));
printf("t1.capacity = %lu ", t1.capacity());//返回当前容量（即string中不必增加内存即可存放的元素个数）
printf("t1.max_size = %lu ", t1.max_size());//返回string对象中可存放的最大字符串的长度
printf("t1.size = %lu ", t1.size());//返回当前字符串的大小
printf("t1.length = %lu ", t1.length());//返回当前字符串的长度

memcpy(&t2, &t1, sizeof(t1));//problem

cout<<"t2 string:"<<t2<<endl;
printf("t2 string:%s ",t2.c_str());//返回一个以null终止的c字符串
printf("sizeof t2 = %lu ", sizeof(t2));
printf("t2.capacity = %lu ", t2.capacity());//返回当前容量（即string中不必增加内存即可存放的元素个数）
printf("t2.max_size = %lu ", t2.max_size());//返回string对象中可存放的最大字符串的长度
printf("t2.size = %lu ", t2.size());//返回当前字符串的大小
printf("t2.length = %lu ", t2.length());//返回当前字符串的长度

return 0;
}

$ ./test
t1 string:123456789
t1 string:123456789
sizeof t1 = 4
t1.capacity = 9
t1.max_size = 1073741820
t1.size = 9
t1.length = 9
t2 string:123456789
t2 string:123456789
sizeof t2 = 4
t2.capacity = 9
t2.max_size = 1073741820
t2.size = 9
t2.length = 9
*** Error in `./test': double free or corruption (fasttop): 0x08120008 ***
Aborted (core dumped)

字符串真是存放地址如下：