C - 为结构数组分配值的分段错误

Question

I am getting segmentation fault whenever I do this. I wonder if there is a way for me to assign a value to the struct without getting SegFault?

typedef struct _chunk
{
  int lo;       // lower bound
  int hi;       // higher bound
} chunk;

chunk_stack = (chunk **)malloc(10 * 10 * sizeof(chunk **));

for (i = 0; i < chunk_per_thread; i++)
{
   chunk_stack[myid][i].lo = 0;
   chunk_stack[myid][i].hi = 1;
}

Answer 1

Suppose you need to allocate a 2D array of size r * c .
You need to first allocate memory for the double pointer which you did but have an error in it ie, one extra * inside malloc function.

chunk **chunk_stack = (chunk **)malloc(r * sizeof(chunk *));

Then you need to allocate memory for each of the rows separately.

for(int i = 0; i < r; i++){
    chunk_stack[i] = (chunk*)malloc(c * sizeof(chunk));
}