Test Deep copy V.S. Superficial copy

techdemo.c

// Online C compiler to run C program online
#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>

typedef struct {
    int baud;
    uint8_t data;
} uart;

void destroy(uart* bus) {
    bus->data = 0;
    bus->baud = 0;
}

int main() {
    /* original pointer */
    uart* uart_bus = (uart*) calloc(1, sizeof(void));
    uart_bus->baud = 0xFF;
    uart_bus->data = 6;
    /* superficial/shallow copy */
    uart* shallow = uart_bus;
    printf("%p\n", uart_bus);
    printf("%p\n", shallow);
    /* deep copy */
    uart* copy = (uart*) calloc(1, sizeof(void));
    copy->baud = uart_bus->baud;
    copy->data = uart_bus->data;
    printf("%p\n", uart_bus);
    printf("%p\n", copy);
    /* test delete on superficial v.s. deep copies */
    destroy(uart_bus);
    printf("%i\n", shallow->data); /* output: 0 */
    printf("%i\n", copy->data); /* output: 6 */
    free(uart_bus); 
    free(shallow); /* free(): double free detected in tcache 2 */

    return 0;
}