Dynamic and static libraries

#[derive(Debug)]
#[repr(C)]
pub struct Point {
    x: i32,
    y: i32
}

#[no_mangle]
pub extern "C" fn new_point(x: i32, y: i32) -> *mut Point {
    let p = Box::new(Point { x: x, y: y });
    Box::into_raw(p)
}

#[no_mangle]
pub extern "C" fn destroy_point(p: *mut Point) {
    unsafe { Box::from_raw(p) };
}

#[no_mangle]
pub extern "C" fn inspect_point(p: *mut Point) {
    unsafe {
        let point: Box<Point> = Box::from_raw(p);
        point.inspect();
    };
}

#include <stdint.h>
#include <stdbool.h>

typedef struct Point {
    int32_t x;
    int32_t y;
} Point;

Point* new_point(int32_t x, int32_t y);

void destroy_point(Point* p);

void inspect(Point* p);

[lib]
crate-type = ["cdylib", "staticlib"]

#include "../include/point.h"

int main (int argc, char const *argv[])
{
        Point* p = new_point(1,1);
        inspect_point(p);
        p->x = 2;
        inspect_point(p);
        destroy_point(p);
}

gcc -L target/debug/ -I include -lc -lm -lSystem -lcore test/test.c -o point

$ ./point
Point { x: 1, y: 1 }
Point { x: 2, y: 1 }
point(98132,0x7fffb30293c0) malloc: *** error for object 0x7fa635c02980: pointer being freed was not allocated
*** set a breakpoint in malloc_error_break to debug
Abort trap: 6

#[no_mangle]
pub extern "C" fn inspect_point(p: *mut Point) {
    unsafe {
        let point: Box<Point> = Box::from_raw(p);
        point.inspect();
        std::mem::forget(point)
    };
}

#[no_mangle]
pub extern "C" fn inspect_point(p: &Point) {
    p.inspect();
}