c++ - Destructor does not destroy objects -


i have written small program, main destructor not working properly. here code of program:

#include<iostream.h>  class citizen { private:     char* name;     char* nationality; public:                  citizen(char* name, char* nationality) {         this->name = name;         this->nationality = nationality;     }                        citizen(const citizen &obj) {         name = obj.name;         nationality = obj.nationality;     }              void display() {         cout << "name: " << name << endl;         cout << "nationality: " << nationality << endl;     }      ~citizen() {          if(name){             delete[]name;         }         if(nationality) {             delete []nationality;                                   }             }        };  main() {    citizen obj1("ali", "pakistani");    obj1.display();    {        citizen obj2 = obj1;                     }    obj1.display();    system("pause"); }

what know in main function i'm assigning state of obj1 obj2, place both of them pointing same memory area. whereas code citizen obj2 = obj1; between 2 curly braces.

   {        citizen obj2 = obj1;                     }

so after execution of second curly brace, obj2 should destroy , delete variables name , nationality. , when call obj1.display(); second time should display garbage on screen.

but obj1 still printing exact name have provided in constructor, though shouldn't be.

please explain behavior.

your delete[]s invoke undefined behavior because you're attempting destroy string literals. anything can happen.

even if allocated memory yourself, you'd still run undefined behavior because you'd attempting access memory you've deleted:

obj1.display(); {     citizen obj2 = obj1;                  } obj1.display();  // illegal

because didn't define assignment operator, compiler-generated 1 used, assigns pointers same memory - memory destroy , attempt access.


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