symbolics_11.py and symbolics_14.py produce invalid code

[certik]

How to reproduce:

$ lpython symbolics_14.py --show-c
[...]
// Implementations
void mmrv(void* x, struct list_CPtr *_lpython_return_variable)
{
    struct list_CPtr l1;
    struct list_CPtr constname0;
    list_init_CPtr(&constname0, 1);
    constname0.data[0] = x;
    constname0.current_end_point = 1;
    list_deepcopy_CPtr(&constname0, &l1);

    list_deepcopy_CPtr(&l1, _lpython_return_variable);

}

The line constname0.data[0] = x; is incorrect, instead it should be basic_assign(constname0.data[0], x);.

The current code thus contains dangling points, so it might or might not segfault.

[certik]

Exactly the same problem is in symbolics_11.py:

$ lpython symbolics_11.py --show-c
[...]
// Implementations
void test_extraction_of_elements()
{
    int64_t _ele1;
    int64_t _ele2;
    int64_t _ele3;
...
    constname0.data[0] = x;
    constname0.data[1] = stack0;
    constname0.data[2] = stack1;
    constname0.data[3] = stack2;
...

[certik]

To fix this, here is a reference code that does the right thing: #2465, so all we need to do now is to ensure the symbolic pass is generating the same ASR as symbolics_15 does.

In particular, instead of a simple assignment, it needs to call basic_assign, and first it needs to initialize constname0.data[3] on heap, just like in symbolics_15.

[anutosh491]

Can be closed as the issue has been correctly fixed through #2465 & #2477