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PO2d QList Memory Leak
 

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  1. PO2d QList Memory Leak
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    <p>I created this 2D Qlist. Code "works" but when I consider a bit deeper the syntax it leaves me wondering whether this code leads to memory leak. </p> <p>I would be great if someone could shed some light on whether this code leads to a mem leak or not. If it does, WHY and how to fix? </p> <p>My Specific concerns are question marked as Q1,Q2,Q3,Q4 in code comments.</p> <p>Also, how should I destroy some rows from lszq2DList and ultimately how should I destroy lszq2DList.</p> <pre><code>//The 2d data sructure. Each row will be a QStringList. QList&lt;QStringList&gt; lszq2DList; //The variable "emptyTempList" is a concern to me. //Q1:: Isn't "emptyTempList" just a pointer to some allocated place in memory? //If so, I imagine it points to some data structure allocated in memory. //Or does this not allocate anything? I have a feeling it does not. QStringList emptyTempList; //I use it in my scheme to make a 2D data struct. for(int i=0; i&lt;3; i++){ //Q2: Because I am in a loop and reusing the same pointer "emptyTempList", //aren't i pointing to the same thing? //If I think about this, each item in my Qlist (each row) should be //pointing to the same place in memory. To whatever "emptyTempList" //points to. //Of course, this is not the case. What is really going on in line bellow? lszq2DList += emptyTempList; //I'm no really pointing to anything am I? QString szqTempString; //Q3: Gets trashed when out of scope? for(int j=0; j&lt;3; j++){ szqTempString.clear(); szqTempString = "jazz"; //QString value gets copied into datastructure? lszq2DList[i] += szqTempString; } } QStringList emptyTempList2; emptyTempList2 += "blues"; emptyTempList2 += "blues"; emptyTempList2 += "blues"; //I'll add another row. lszq2DList += emptyTempList2; //Q4: lszq2DList[3] does not point to emptyTempList2, right? //Instead it copies all the strings //from to emptyTempList2 to lszq2DList[3], right? </code></pre>
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    1. USuser440297
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    1. COyour posted code doesn't even have any memory allocations, how could it have any leaks?
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      1. USDavid Titarenco
 

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