//测试c++中结构体的字节对齐
#include <iostream>
#include <cmath>
using namespace std;
void vsVersion();
//example 1
struct Node1
{
char a;
int b;
double c;
};
//example 2
struct Node2
{
char a;
int b;
char c;
};
//example 3
struct Node3
{
};
//example 4
struct Node4
{
char a;
int b;
static double c;
};
//example 5
struct Inside
{
int a;
double b;
float c;
};
struct Node5 {
char e[2];
int f;
short h;
struct Inside inside;
};
//example 6
struct Node6 {
char a;
int b;
float c;
double d;
int* p;
char* pc;
short e;
};
int main()
{
Node1 n1;
Node2 n2;
Node3 n3;
Node4 n4;
Node5 n5;
Node6 n6;
vsVersion();
//宏定义:https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros?redirectedfrom=MSDN&view=vs-2019
#ifdef _WIN64
cout << "--------x64----------------" << endl;
cout << "char:" << sizeof(char) << endl;
cout << "short:" << sizeof(short) << endl;
cout << "int:" << sizeof(int) << endl;
cout << "double:" << sizeof(double) << endl;
cout << "float:" << sizeof(float) << endl;
cout << "char *:" << sizeof(char *) << endl;
cout << "Node1 :" << sizeof(n1) << endl;
cout << "Node2 :" << sizeof(n2) << endl;
cout << "Node3 :" << sizeof(n3) << endl;
cout << "Node4 :" << sizeof(n4) << endl;
cout << "Node5 :" << sizeof(n5) << endl;
cout << "Node6 :" << sizeof(n6) << endl;
#else
cout << "--------x86----------------" << endl;
cout << "char:" << sizeof(char) << endl;
cout << "short:" << sizeof(short) << endl;
cout << "int:" << sizeof(int) << endl;
cout << "double:" << sizeof(double) << endl;
cout << "float:" << sizeof(float) << endl;
cout << "char *:" << sizeof(char*) << endl;
cout << "Node1 :" << sizeof(n1) << endl;
cout << "Node2 :" << sizeof(n2) << endl;
cout << "Node3 :" << sizeof(n3) << endl;
cout << "Node4 :" << sizeof(n4) << endl;
cout << "Node5 :" << sizeof(n5) << endl;
cout << "Node6 :" << sizeof(n6) << endl;
#endif
cout << "hello world" << endl;
return 0;
}
//确定IDE版本
void vsVersion()
{
if (_MSC_VER == 1921 or _MSC_VER == 1922 or _MSC_VER == 1923)
{
cout << "vs2019" << endl;
}
else if (_MSC_VER == 1910 or _MSC_VER == 1911 or _MSC_VER == 1912 or _MSC_VER == 1913 or _MSC_VER == 1914 or _MSC_VER == 1915 or _MSC_VER == 1916)
{
cout << "vs2017" << endl;
}
else
{
cout << "others" << endl;
}
}
[c++11]结构体字节对齐
猜你喜欢
转载自www.cnblogs.com/tailiang/p/11718814.html
今日推荐
周排行