Thread: Wild Pointers?!!

  1. #1
    Registered User
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    Wild Pointers?!!

    I'm currently learning about Pointers...
    The book says that wild pointers " pointers that are not initialized " are VERY dangerous!

    why are they dangerous ?
    I have a code which stops life!

  2. #2
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    Because they don't point to anything, meaning they could crash your program. Also read up on pointers, after you are done you should intialise them to NULL.

  3. #3
    &TH of undefined behavior Fordy's Avatar
    Join Date
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    5,793
    An uninitialised pointer could point to any location. So if you;

    int* ptrI;
    *ptrI = 10;

    It may work once or twice (because the location of the pointer may point to a safe area of memory), but then crash without warning then next time.

    If you;

    int* ptrI = 0;
    *ptrI = 10;

    Then it will crash every time, but the reason for the crash given by your debugger or the os gives you good hint to look for a point in your code where you dereference a null pointer

  4. #4
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    Uninitialized pointerse point to a location in mem. If you don't assign them values, they use the values that are already in the little ram piece they've selected.

    try this and see for yourself:

    Code:
    int* x;
    cout << *x;
    Very annoying.

    --Ashiq

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