Thread: Have I just created a memory leak ?

  1. #1
    Registered User
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    Question Have I just created a memory leak ?

    Hi,

    At the beginning of main() I have :-
    Code:
    int main()
    {
       record tempRecord;
       record * theRecords = NULL;
       record * newRecord = &tempRecord;
    At the end of main() I have :-
    Code:
       /* Free up allocated memory */
       newRecord = NULL;
       free(theRecords);
       theRecords = NULL;
       return 0;
    }  /* end main() */
    By setting newRecord to NULL, and given that the fields of newRecord at this point still contain data for the last record added, have I just created a memory leak ? If so, do I have to clear the fields of newRecord before setting it to NULL or is that a moot point at this point in main() ?

    Stuart

  2. #2
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    It's hard to see exactly what is going on here. You've left out the important part that would show what kind of structure is being maintained with these variables.
    Does theRecords point to a linked list?
    If so, then free(theRecords) will only delete the first node and potentially leak the rest.
    The whole problem with the world is that fools and fanatics are always so certain of themselves, but wiser people so full of doubts. - Bertrand Russell

  3. #3
    and the hat of int overfl Salem's Avatar
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    Without seeing all your malloc and free calls, it's impossible to say.

    Run the program through valgrind if you want a diagnostic.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.

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