Two-dimensional array problem - static vs. dynamic approach

Hi,

the code below ends with EXC_BAD_ACCESS when I run it. I also get a warning message from the compiler telling me that array_s is an incompatible pointer type when calling the fill_array function. Where is the problem? If I write similar code working with one-dimensional array, it functions properly.

Code:

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#define ROWS 3
#define COLUMNS 4

void fill_array(int **arr, int rows, int columns)
{
        int i, j;
        for (i = 0; i < rows; i++)
                for (j = 0; j < columns; j++)
                        arr[i][j] = columns * i + j;
                       
}

int main (int argc, const char * argv[])
{
    int array_s[ROWS][COLUMNS];
    fill_array(array_s, ROWS, COLUMNS);
    return 0;
}

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Question 6.18
Next time, please read c-faq before asking here.

Quote:

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Where is the problem?

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array_s is an incompatible pointer type to what fill_array expects. The first dimension of an array decays into a pointer, but only the first dimension. array_s becomes int(*)[4] but fill_array expects int**. A simpler rule to remember is a 2D array of T is not compatible with a double pointer to T.

Quote:

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Originally Posted by kkk

Where is the problem?

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The problem is you not listening to your compiler. Turn up your warning levels, and pay attention to them.


Quzah.