[Inconsistent with solc]: Nested mapping not working.

[Subway2023]

Solang version: v0.3.3-70-g32a45ea1
Description: In solc + EVM, the value of y is 3, but in solang + SVM, the value of y is 0. The reason is that the nested map cannot be assigned values correctly, while a regular map can.

Reproduction: I set up a Solang compilation and execution environment to test the program.

contract C {
  uint gleft;
  mapping(uint => mapping(uint => uint)) nestedMap;
  function f() public payable returns (int) {
    int result = 0;
    nestedMap[1][2] = 3;
    result += int(nestedMap[1][2]);

    return result;
  }
}