lpython emits invalid c code when passing an object to a function

[emoise-gsi]

lpython version: 18.2

This a variation of a bug I opened in the past (#2059). The bug was fixed but it has morphed into something else.

Consider the code, pass_address_bug.py:

from lpython import packed, dataclass, ccallable, i32, ccallback

@ccallable
@packed
@dataclass
class struct_0:
    val_0 : i32 = 613

@ccallable
@packed
@dataclass
class struct_1:
    val_1 : struct_0 = struct_0()

def print_val_0_in_struct_0(struct_0_instance : struct_0) -> i32:
    print(struct_0_instance.val_0)
    return 0

@ccallback
def entry_point() -> i32:
    struct_1_instance : struct_1 = struct_1()  
    return print_val_0_in_struct_0(struct_1_instance.val_1)

compiling with lpython,
$ lpython pass_address_bug.py --show-c > bug.c

produces the following code, bug.c:

#include <inttypes.h>

#include <stdlib.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <lfortran_intrinsics.h>

struct dimension_descriptor
{
    int32_t lower_bound, length;
};
struct __attribute__((packed)) struct_0 {
 int32_t val_0;
};

struct __attribute__((packed)) struct_1 {
 struct struct_0 val_1;
};


// Implementations
int32_t print_val_0_in_struct_0(struct struct_0* struct_0_instance)
{
    int32_t _lpython_return_variable;
    printf("%d\n", struct_0_instance->val_0);
    _lpython_return_variable = 0;
    return _lpython_return_variable;
}

int32_t entry_point()
{
    int32_t _lpython_return_variable;
    struct struct_1 struct_1_instance_value;
    struct struct_1* struct_1_instance = &struct_1_instance_value;
    struct_1_instance->val_1.val_0 = 613;
    _lpython_return_variable = print_val_0_in_struct_0(struct_1_instance->val_1);
    return _lpython_return_variable;
}

int main(int argc, char* argv[])
{
    _lpython_set_argv(argc, argv);
    return 0;
}

The problem is in the line:
_lpython_return_variable = print_val_0_in_struct_0(struct_1_instance->val_1);
It should be
_lpython_return_variable = print_val_0_in_struct_0(&struct_1_instance->val_1);

Note that the following code, pass_address_works.py, is compiled correctly:

from lpython import packed, dataclass, ccallable, i32, ccallback

@ccallable
@packed
@dataclass
class struct_0:
    val_0 : i32 = 613

@ccallable
@packed
@dataclass
class struct_1:
    val_1 : struct_0 = struct_0()

def print_val_0_in_struct_0(struct_0_instance : struct_0) -> None:
    print(struct_0_instance.val_0)

@ccallback
def entry_point() -> i32:
    struct_1_instance : struct_1 = struct_1()  
    print_val_0_in_struct_0(struct_1_instance.val_1)
    return 0

[Shaikh-Ubaid]

The last time we fixed it for a subroutine (struct passed to subroutine). This time it seems we have a struct passed to a function. I fixed it here #2180.