badvoidpointerdeletion.cpp

ThinkingC++中文版

//: C13:BadVoidPointerDeletion.cpp
// From Thinking in C++, 2nd Edition
// Available at http://www.BruceEckel.com
// (c) Bruce Eckel 2000
// Copyright notice in Copyright.txt
// Deleting void pointers can cause memory leaks
#include <iostream>
using namespace std;

class Object {
  char* data; // Some storage
  const int size;
  const char id;
public:
  Object(int sz, char c) : size(sz), id(c) 
  {
    data = new char[size];
    cout << "Constructing object " << id << ", size = " << size << endl;
  }
  ~Object() 
  { 
    cout << "Destructing object " << id << endl;
    delete []data; // OK, just releases storage,
    // no destructor calls are necessary
  }
};

void main() 
{
  Object* a = new Object(40, 'a');
  delete a;
  void* b = new Object(40, 'b');
  delete b;
} ///:~