C++之delete常见错误总结

   

    

     

      

     
     

      

       int main()
      
     
    

     

      

     
     

      

       {
      
     
    

     

      

     
     

      

          int *a = new int(50);
      
     
    

     

      

     
     

      

          cout<<*a<<endl;
      
     
    

     

      

     
     

      

        delete a;
      
     
    

     

      

     
     

      

        delete a;
      
     
    

     

      

     
     

      

        return 0;
      
     
    

     

      

     
     

      

       }
      
     
   
  

2）另外一个指针指向分配的内存，然后把这个2个指针都删除

   

    

     

      

     
     

      

       int* p1 = new int(50);
      
     
    

     

      

     
     

      

       int* p2 = p1; //p2和p1 现在指向同一内存地址
      
     
    

     

      

     
     

      

       cout << *p1 << endl;
      
     
    

     

      

     
     

      

       cout << *p2 << endl;
      
     
    

     

      

     
     

      

       delete p1; //OK
      
     
    

     

      

     
     

      

       delete p2; //ERROR! p2所指的内存，已通过delete p1而被释放，不可再delete一次
      
     
    

     

      

     
     

      

     
   
  

2、删除是一个普通指针或者不是一个指针

   

    

     

      

     
     

      

       nt  a = 50;
      
     
    

     

      

     
     

      

       int *p = &a;
      
     
    

     

      

     
     

      

       delete p
      
     
   
  

2) 删除的不是一个指针

   

    

     

      

     
     

      

       string ss = "chenyu";
      
     
    

     

      

     
     

      

       delete ss;
      
     
   
  

3、删除了由系统释放