dynptr(&mut) compiles but doesn’t work

[numberZero]

E.g. in this small example the assertion fails:

#[stabby::stabby]
pub trait Iface {
    extern "C" fn set(&mut self, val: i32);
}

struct Impl {
    cookie: i32,
}

impl Iface for Impl {
    extern "C" fn set(&mut self, val: i32) {
        println!("set({:?}, {})", self as *mut _, val);
        self.cookie = val;
    }
}

fn main() {
    let mut val = Impl { cookie: 42 };
    println!("val is at {:?}", (&val) as *const _);
    let mut ptr: stabby::dynptr!(&'_ mut dyn Iface) = (&mut val).into();
    println!("ptr is at {:?}", (&ptr) as *const _);
    ptr.set(13);
    drop(ptr);
    assert_eq!(val.cookie, 13);
}

The output is suspicious:

val is at 0x7fffd73e8f54
ptr is at 0x7fffd73e8fb0
set(0x7fffd73e8fb0, 13)
thread 'main' panicked at src/main.rs:24:5:
assertion `left == right` failed
  left: 42
 right: 13
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

Apparently somehow, pointer to ptr instead of its value is passed to set.

Versions

stabby 36.2.2
rustc 1.84.0 (9fc6b4312 2025-01-07)

[numberZero]

...and this example downright crashes with a segmentation fault:

#[stabby::stabby]
pub trait Iface {
    extern "C" fn strike(&mut self);
}

#[repr(C)]
struct Victim<'a> {
    ptr: stabby::dynptr!(&'a mut dyn Iface),
    target: Box<u8>,
}

#[repr(C)]
struct Attack {
    pad1: isize,
    pad2: isize,
    target: isize,
}

impl Iface for Attack {
    extern "C" fn strike(&mut self) {
        self.target = 0;
    }
}

fn main() {
    let mut val = Attack {
        pad1: 0,
        pad2: 0,
        target: 0,
    };
    let mut vic = Victim {
        ptr: (&mut val).into(),
        target: Box::new(42),
    };
    vic.ptr.strike();
    println!("The answer is {}", vic.target);
}