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Heap Corruption Error on delete

tkurowski (17)
Hello Everyone,

I'm having problems deleting a new variable!
I have done exactly as is shown elsewhere on the website:

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#define HEIGHT 5
#define WIDTH 3
#define DEPTH 7

int main() {
  double ***p2DArray;

  // Allocate memory
  p2DArray = new double**[HEIGHT];
  for (int i = 0; i < HEIGHT; ++i) {
    p2DArray[i] = new double*[WIDTH];

    for (int j = 0; j < WIDTH; ++j)
      p2DArray[i][j] = new double[DEPTH];
  }

  // Assign values
  p2DArray[0][0][0] = 3.6;
  p2DArray[1][2][4] = 4.0;

  // De-Allocate memory to prevent memory leak
  for (int i = 0; i < HEIGHT; ++i) {
    for (int j = 0; j < WIDTH; ++j)
      delete [] p2DArray[i][j];

    delete [] p2DArray[i];
  }
  delete [] p2DArray;

  return 0;
}


The problem happens on the second iteration of the second for loop
(ie at delete [] p2DArray[i][j])

What is the problem?

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	//Initialize picture temporary memory matrix
	unsigned int *** picTemp = new unsigned int ** [cyScreen];
	for ( unsigned int i = 0; i < cyScreen; i++ )
	{
		picTemp[i] = new unsigned int * [cxScreen];

		for ( unsigned int j = 0; j < cxScreen; j++ )
			picTemp [i] [j] = new unsigned int [3]; //3 layers for a picture
	}
...
...
...
	for ( int i = 0; i < cyScreen; i++ )
	{
		for ( int j = 0; j < cxScreen; j++ )
		{
			delete [] picTemp [i] [j];
		}

		delete [] picTemp [i];
	}
	delete [] picTemp;



In this case, cxScreen = 1280, cyScreen = 800.

Cheers,
Tom
Last edited on
helios (17574)
Your first example looks and works fine for me.
jsmith (5804)
Something can't be right... there are 2 new's and 3 delete's.

Memory is being mismanaged; there should be an equal number of both.
Last edited on
closed account (z05DSL3A)
I count three new and deletes in both examples!
jsmith (5804)
Whoops, missed line 2 in the second example... never mind :)
closed account (z05DSL3A)
The corruption likely happens in the code between newing and deleteing:

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#include<iostream>
#define HEIGHT 10
#define WIDTH 10
#define DEPTH 3

int main() {
  unsigned ***p2DArray;

  // Allocate memory
  p2DArray = new unsigned**[HEIGHT];
  for (int i = 0; i < HEIGHT; ++i) 
  {
    p2DArray[i] = new unsigned*[WIDTH];

    for (int j = 0; j < WIDTH; ++j)
    {
      p2DArray[i][j] = new unsigned[DEPTH];
    }
  }

  // Assign values
  for (int i = 0; i < HEIGHT; ++i)
  {
      for(int j = 0; j < WIDTH; ++j)
      {
        p2DArray[i][j][0] = 1;
        p2DArray[i][j][1] = 2;
        p2DArray[i][j][2] = 3;
      }
  }

  // This line will cause a heap corruption to be shown
  // when delteing the memory
  p2DArray[1][1][4] = 2;

  // De-Allocate memory to prevent memory leak
  for (int i = 0; i < HEIGHT; ++i) 
  {
    for (int j = 0; j < WIDTH; ++j)
    {
        std::cout << i << ":" << j << std::endl;
        delete [] p2DArray[i][j];
    }
    delete [] p2DArray[i];
  }
  delete [] p2DArray;

  return 0;
}

NB: it will probable only show when debugging
Last edited on
tkurowski (17)
Excellent, thank you guys.
I was looking for it but I skimmed over it so easily because I'm used to MatLab starting their indexing from 1!

In my main code I was accessing picTemp[i][j][3] sometimes. So I switcherooed that and its perfect now.

Thanks very much!
Tom
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