C语言结构体的字节对齐

Test Code:

 1 #include <iostream>
 2 #include <cstring>
 3
 4 using namespace std;
 5
 6 struct A{
 7     int a;
 8     short b;
 9     char d;
10     char e[10];
11 };
12
13 struct B{
14     int a;
15     short b;
16     char *c;
17     char d;
18     char e[10];
19 };
20
21 int main(){
22
23     cout<<sizeof(A)<<endl;
24     cout<<sizeof(B)<<endl;
25     cout<<"short "<<sizeof(short)<<endl;
26     cout<<"int "<<sizeof(int)<<endl;
27     cout<<"long "<<sizeof(long)<<endl;
28     cout<<"char* "<<sizeof(char*)<<endl;
29
30     return 0;
31
32 }

Output(Fedora 64bit):

20
32
short 2
int 4
long 8
char* 8