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Thread: strange delete occurance

  1. #1
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    Default strange delete occurance

    Hi, I have a problem I don't understand the behaviour.

    I have a slot and there a instantiate a QList<int*>*;

    Qt Code:
    1. void Class::slot()
    2. {
    3. QList<int>* list = new QList<int>();
    4. qDebug() << "list_adress: " << list; //i.e. 0x7fbc24034870
    5. deleteList(list);
    6. qDebug() << "list_adress: " << list; // i expect 0x0, but output is 0x7fbc24034870
    7. }
    8.  
    9. void Class::deleteList(QList<int>* list)
    10. {
    11. delete list;
    12. list = NULL;
    13. }
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    Why pointer is not deleted in slot?
    Please help me!!??

  2. #2
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    Default Re: strange delete occurance

    It is deleted. It's just not nulled, because you are nulling a copy of the pointer. And next time please post in the right forum, it is not a Qt issue.
    Your biological and technological distinctiveness will be added to our own. Resistance is futile.

    Please ask Qt related questions on the forum and not using private messages or visitor messages.


  3. The following user says thank you to wysota for this useful post:

    Qiieha (31st May 2012)

  4. #3
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    Default Re: strange delete occurance

    Try this:
    Qt Code:
    1. void Class::slot()
    2. {
    3. QList<int>* list = new QList<int>();
    4. qDebug() << "list_adress: " << list; //i.e. 0x7fbc24034870
    5. deleteList(&list);
    6. qDebug() << "list_adress: " << list; // i expect 0x0, but output is 0x7fbc24034870
    7. }
    8.  
    9. void Class::deleteList(QList<int>** list)
    10. {
    11. delete *list;
    12. *list = NULL;
    13. }
    To copy to clipboard, switch view to plain text mode 

  5. The following user says thank you to StrikeByte for this useful post:

    Qiieha (31st May 2012)

  6. #4
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    Default Re: strange delete occurance

    @wysota: sorry...and thanks

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