io-uring: LinkTimeout randomly ignored

I have noticed in my program, that when adding a LinkTimeout operation after a Connect, sometimes (randomly) the timeout is ignored and the connect operation blocks forever.

It seems to occur more frequently when the binary is compiled in release mode.

I have made a minimal program, which allows me to reproduce 100% of the time (run with cargo run --release), the program should not block more that 3 seconds, but it does:

Cargo.toml:

[package]
name = "io_uring_test"
version = "0.1.0"
edition = "2021"

[dependencies]
io-uring = "0.5.9"
nix = { version = "0.25.0", default-features = false, features = ["net", "socket"] }

src/main.rs:

use io_uring::{
    opcode, squeue,
    types::{Fd, Timespec},
    IoUring,
};
use nix::sys::socket::{socket, AddressFamily, SockFlag, SockType, SockaddrIn, SockaddrLike};

fn main() {
    let mut ring = IoUring::new(8).unwrap();

    let sckt = socket(
        AddressFamily::Inet,
        SockType::Stream,
        SockFlag::empty(),
        None,
    )
    .unwrap();
    let addr = SockaddrIn::new(37, 187, 0, 1, 80);  // an IP that does not respond

    let op_connect = opcode::Connect::new(Fd(sckt), addr.as_ptr(), addr.len())
        .build()
        .flags(squeue::Flags::IO_LINK)
        .user_data(1);

    let op_connect_timeout = opcode::LinkTimeout::new(&Timespec::new().sec(3))
        .build()
        .user_data(2);

    let ops = [op_connect, op_connect_timeout];

    eprintln!("{ops:?}");

    for op in &ops {
        unsafe {
            ring.submission().push(op).unwrap();
        }
    }

    ring.submit_and_wait(2).unwrap();
}

EDIT: removed use of unsafe feature flag.