我们经常会定义一个char数组作为缓存接收数据，然后将接收的数据转换为某一个结构体。这里通常要求数组按照结构体的要求对齐。那么默认的cha数组是对齐到多少呢？1还是？如果为1的话，意味着我们要显示地给出对齐要求。查到的资料是，局部或全局数组如果大于16个字节会对齐到16字节。
https://stackoverflow.com/questions/22598992/alignment-of-char-array-struct-members-in-c-standard
An array uses the same alignment as its elements, except that a local or global array variable of length at least 16 bytes or a C99 variable-length array variable always has alignment of at least 16 bytes