vector doesn't initialize

Hi all, having a little trouble figuring out why I'm getting a seg fault. I'll post the relevant snippets of code preceded by a quick description.

First, the cloning function. This is where I suspect the problem is. I think the memory for the local object is getting deleted once the function finishes.

Matrix* Matrix::clone()
{
    Matrix mat(m_rows, m_cols);
    for (int i = 0; i < m_rows; i++)
    {
        for (int k = 0; k < m_cols; k++)
        {
            mat.set(i, k, m_mat[i*m_cols+k]);
            cout << mat.get(i, k) << endl;
        }
    }
    return &mat;
}

Where the actual seg fault occurs and what calls the method.

double Matrix::get(const int row, const int col)
{
    return m_mat[row*m_cols+col];
}

void Matrix::debug()
{
    for (int i = 0; i < m_rows; i++)
    {
        for (int k = 0; k < m_cols; k++)
        {
            cout << get(i, k) << " ";
        }
        cout << endl;
    }
}

Now the code from main that starts everything.

1
2

Matrix* cloned_p = mat_p->clone();
cloned_p->debug();

I also tried returning a Matrix from clone() but that's a totally different problem. Any ideas? I'll also be willing to hear random other helpful comments if you're kind enough to offer them. Thanks a ton in advance for insight into the problem.

ne555 (10692)

At the end of the function the program automatically call the destructor of its variables. The memory will be freeing, (if you allocate your matrix dynamical, I suppose you've got a delete in ~Matrix() ).
Could try this

 Matrix* Matrix::clone(){
    Matrix *mat = new Matrix(m_rows, m_cols);
    //...
    return mat;
}
//or avoid pointers
void Matrix::clone(Matrix &m);

guestgulkan (2942)

another option is to use the copy constructor:

Matrix* Matrix::clone(){
    Matrix *mat = new Matrix(*this);
 
    return mat;
}

canonseer (4)

Matrix uses the custom destructor. Your advice about Matrix* mat worked perfectly, thanks.

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vector doesn't initialize