字节对齐之包含嵌套struct

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struct example1
{
  short a;
  long b;
};

struct example2
{
  char c;
  example1 struct1;    ---------------这里structur1就是一个自定义类型的变量,它的自身对齐长度为struct example1的有效对齐长度4,它所占内存为sizeof(t example1)的长度
  short e;
}

int main(int argc,char*argv[])
{
   example2 e2;
   int d = (unsigned int)&e2.struct1 - (unsigned int)&e2.c;
   printf("%d,%d,%d\n", sizeof(example1),sizeof(example2),d);
}

8bytes 对齐时,结果为:
8,16,4

内存分布为连续内存:

                         <-------4bytes------>
example2 ---->-------------------------
                         | c    |    补0            |
                         |       |                      |
example1----->-------------------------
                         |a     |     补0           |
                         |       |                       |
                         ---------------------------
                         | b                           |
                         |                              |
                         --------------------------
                         |e      |   补0            |
                         |        |                      |

                         --------------------------
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