One-dimensional VLAs are (kind of) supported via turning them into alloca calls.
But this fails for multidimensional arrays:

int main() {
  int x = 1;
  int y = 1;
  int m[x][y];

  m[0][0] = 0;
} 

leads to Error: Cannot resolve variable m.

Changing it to int m[x][1]; makes it work again.