Can anybody explain this line?

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  1. #1
    In the Land of Diddly-Doo g4j31a5's Avatar
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    Wink Can anybody explain this line?

    Hi, can anybody explain this code? I saw this on a proprietary 3rd party library so I don't quite understand what it is trying to achieve. I don't understand the reason for the reinterpret casting. It seems redundant (CMIIW). Why would anyone want to do that? Thanks in advance.

    Code:
    ...
    private:
    T *freeListHead;
    
    T *myfunction()
    {
        ...
        freeListHead = *(reinterpret_cast<T**>(freeListHead));
        return freeListHead ;
    }
    ERROR: Brain not found. Please insert a new brain!

    “Do nothing which is of no use.” - Miyamoto Musashi.

  2. #2
    Algorithm Dissector iMalc's Avatar
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    It's not redundant, it's treating the freeListHead variable as if it had a different level of indirection. The code must have a linked list where the next pointer is basically at the same address as the item pointed to. That is not the clearest way to write it, but it works. I've done it that way before I learnt how to do it cleaner.
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  3. #3
    In the Land of Diddly-Doo g4j31a5's Avatar
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    Quote Originally Posted by iMalc View Post
    It's not redundant, it's treating the freeListHead variable as if it had a different level of indirection. The code must have a linked list where the next pointer is basically at the same address as the item pointed to. That is not the clearest way to write it, but it works. I've done it that way before I learnt how to do it cleaner.
    You're right. Silly me for not noticing earlier. It is a linked list. And a peculiar one I must say.

    Thanks. Consider the problem solved.

    Now, back to the memory leak problem. The debugging never ends.
    ERROR: Brain not found. Please insert a new brain!

    “Do nothing which is of no use.” - Miyamoto Musashi.

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