Cant cope with an error (destructor destroys everything)

Question

I face this problem:

No source available.
Call stack location: lab5.exe! Counter:: 'scalar deleting destructor'() + 0x2b bytes.

I construct a single linked list.

counter.h

class Counter{
    private:
        char* m_pStr; 
        unsigned int m_nOwners; 
        Counter* pNext;         
        static unsigned int m_curCounters;
        static Counter* Head;   
...

counter.cpp

Counter* Counter:: Head = new Counter();
unsigned int Counter:: m_curCounters = 0;

Counter:: ~Counter(){
    if  (this == Head){
        Head = Head->pNext;
    }
    else{
        Counter* current = Head->pNext;
        for (int i = 0; i < m_curCounters; i++){
            if (current->pNext == this){
                            // Searching for counter, with next one equal this.
                current->pNext = this->pNext;
                break;
            }
            current = current ->pNext;
        }
    }
    m_curCounters--;
    delete[] this->m_pStr;
}

The closing brace leads to the error. In the pictures: one step separates me from the error screen and the error itself.

Screenshot 1 Screenshot 2 Screenshot 3

P.S. Vectors are forbidden.

Read about the [rule of three](http://en.wikipedia.org/wiki/Rule_of_three_%28C%2B%2B_programming%29). — Some programmer dude, Apr 19 '13 at 15:08
By the way, please show your constructor as well. You _do_ set e.g. `pNext` to `nullptr` there? — Some programmer dude, Apr 19 '13 at 15:10
Well, I have read it thank you. But I still can't see my fault. — Trts, Apr 19 '13 at 15:11
If instances of the class can be copied or assigned, then you need to do a _deep_ copy, not only copy the pointer or all copies will share the same data. — Some programmer dude, Apr 19 '13 at 15:14

score 2 · Accepted Answer · edited May 23 '17 at 11:50

2

Your class needs to follow the Rule of Three.
You need to provide a copy constructor & copy assignment operator which perform deep copies of the dynamically allocated data members.

Alternatively, You can use a smart pointer instead of a raw pointer. This will save you all the explicit manual memory management.

Also, you are much better off replacing char * with std::string.

edited May 23 '17 at 11:50

Community

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answered Apr 19 '13 at 15:09

Alok Save

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I failed to construct these two constructors as Head is static. – Trts Apr 19 '13 at 15:14
Its [rule of 5](http://stackoverflow.com/questions/4782757/rule-of-three-becomes-rule-of-five-with-c11) since C++11 :) – Apr 19 '13 at 15:17
@VladLazarenko: True, but I don't really think OP is using C++11. – Alok Save Apr 19 '13 at 15:18

Cant cope with an error (destructor destroys everything)

1 Answers1