1  extern void abort (void);
       2  
       3  static int inv_J(int a[][2])
       4  {
       5    int i, j;
       6    int det = 0.0;
       7     for (j=0; j<2; ++j)
       8       det += a[j][0] + a[j][1];
       9    return det;
      10  }
      11  
      12  int foo()
      13  {
      14    int mat[2][2];
      15    mat[0][0] = 1;
      16    mat[0][1] = 2;
      17    mat[1][0] = 4;
      18    mat[1][1] = 8;
      19    return inv_J(mat);
      20  }
      21  
      22  int main()
      23  {
      24    if (foo () != 15)
      25      abort ();
      26    return 0;
      27  }
      28