在c++中找不到内存泄漏

Question

我运行调用createNewMatrix的createNewBoard，然后退出程序，但是我找不到内存泄漏。下面是代码

BoardP createNewBoard(int width, int high)
{
    BoardP board = (BoardP) malloc(sizeof(Board));

    if (board == NULL)
    {
        reportError(MEM_OUT);
        return NULL;
    }
    board->height = high;
    board->width = width;
    board->matrix = createNewMatrix(width,high);
    printf("%c",board->matrix[1][1]);
    if (board->matrix == NULL)
    {
        reportError(MEM_OUT);
        freeBoard(board);
    return NULL;
    }
return board;
}

static char** createNewMatrix(int width, int height){
    char** newMatrix = (char**) calloc(height,sizeof(char*));
    int i;
    for (i=0; i<height; i++)
    {
        newMatrix[i] = (char*) calloc(width,sizeof(char)); //LINE 71
        if (newMatrix[i] == NULL)
        {
            int j;
            for (j=0; j<i; j++)
            {
                free(newMatrix[j]);
            }
            free(newMatrix);
            return NULL;
        }
    }
    return newMatrix;
 }

我都快疯了。我所要做的就是创建一个指向Board结构的指针(它包含整数和一个二维指针数组)，并且我有一个内存泄漏。下面是要传达的信息：

==10436== HEAP SUMMARY:
==10436==     in use at exit: 100 bytes in 10 blocks
==10436==   total heap usage: 12 allocs, 2 frees, 196 bytes allocated
==10436== 
==10436== 100 bytes in 10 blocks are definitely lost in loss record 1 of 1
==10436==    at 0x4C2380C: calloc (vg_replace_malloc.c:467)
==10436==    by 0x4008C6: createNewMatrix (Board.c:71)
==10436==    by 0x40081E: createNewBoard (Board.c:55)
==10436==    by 0x4007C6: createNewDefaultBoard (Board.c:37)
==10436==    by 0x400F0C: main (PlayBoard.c:11)
==10436== 
==10436== LEAK SUMMARY:
==10436==    definitely lost: 100 bytes in 10 blocks
==10436==    indirectly lost: 0 bytes in 0 blocks
==10436==      possibly lost: 0 bytes in 0 blocks
==10436==    still reachable: 0 bytes in 0 blocks
==10436==         suppressed: 0 bytes in 0 blocks

它将我指向第71行，它调用calloc作为矩阵中的一行。当程序退出时，它会调用freeBoard：

void freeBoard(BoardP board)
{
    if (board != NULL)
    {
        if(board->matrix != NULL)
        {
            free(board->matrix);
        }
        free(board);
    }
}

你知道为什么我会有内存泄漏吗？谢谢!

Answer 1

在释放matrix之前，您必须先释放单独的行。

for (i=0; i<height; i++)
{
    free(board->matrix[i]);
}

Answer 2

对于矩阵，您可以为所有元素分配内存，但不能在函数freeBoard()中释放它们。

Answer 3

我看不出有什么混淆，您显然没有释放任何大小为width*sizeof(char)的height数组。根据输出，height和width都是10。