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#include <iostream>

#include <cstdlib>

using namespace std;

class Bad{};

// 一个对象new的时候先调用new分配内存 然后调用构造函数 如果ctor出现异常 就调用delete来释放内存防止内存泄露

// 仅限g2.9 该部分了解即可

class Foo {

public:

Foo(){cout<<"Foo::Foo()"<<endl;}

// 故意抛出异常 测试调用重载的delete

Foo(int min) {cout<<"Foo::Foo(min)"<<endl; throw Bad();}

// #1 一般的new重载

void* operator new(size_t size) {

return malloc(size);

}

// #2 placement new

// Foo* p = new(200)Foo; 这样调用

void* operator new(size_t size, long extra) {

return malloc(size+extra);

}

// 对应#1

void operator delete(void* , size_t) {

cout << "operator delete(void*, size_t)" << endl;

}

// 对应#2

void operator delete(void* , long) {

cout << "operator delete(void*, long)" << endl;

}

};

int main() {

Foo* p1 = new(300)Foo(1);

}