`src/rt/object.rs`: `index out of bounds: the len is 0 but the index is [number-bigger-than-0]`

[vincent-thomas]

NOTE: This library where this loom bug lies, is a low level library and this currently can only be reproduced on macos.

On every test I use loom::model on this panic shows up.

Example errors:

    thread 'test_accept_ipv6' panicked at /Users/vt/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/loom-0.7.2/src/rt/object.rs:382:50:
    index out of bounds: the len is 0 but the index is 4
    stack backtrace:
       0: __rustc::rust_begin_unwind
       1: core::panicking::panic_fmt
       2: core::panicking::panic_bounds_check
       3: loom::rt::object::Ref<T>::set_action
       4: scoped_tls::ScopedKey<T>::with
       5: loom::rt::atomic::Atomic<T>::rmw
       6: loom::sync::atomic::int::AtomicU64::fetch_add
       7: lio::driver::Driver::reserve_driver_entry
       8: lio::accept
       9: <tokio::future::maybe_done::MaybeDone<Fut> as core::future::future::Future>::poll
      10: <core::future::poll_fn::PollFn<F> as core::future::future::Future>::poll
      11: test_accept::test_accept_ipv6::{{closure}}::{{closure}}
      12: tokio::runtime::scheduler::current_thread::Context::enter
      13: tokio::runtime::context::scoped::Scoped<T>::set
      14: tokio::runtime::scheduler::current_thread::CoreGuard::block_on
      15: tokio::runtime::context::runtime::enter_runtime
      16: lio::loom::test_utils::block_on
      17: core::ops::function::FnOnce::call_once{{vtable.shim}}
      18: generator::stack::StackBox<F>::call_once
      19: generator::detail::gen::gen_init_impl
      20: generator::detail::asm::gen_init
    note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

        FAIL [   2.440s] lio::test_accept test_accept_concurrent
  stdout ───

    running 1 test
    ERROR generator::detail::gen: set panic inside generator
    test test_accept_concurrent ... FAILED

    failures:

    failures:
        test_accept_concurrent

    test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 4 filtered out; finished in 2.43s

  stderr ───

    thread 'test_accept_concurrent' panicked at /Users/vt/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/loom-0.7.2/src/rt/object.rs:382:50:
    index out of bounds: the len is 0 but the index is 4
    stack backtrace:
       0: __rustc::rust_begin_unwind
       1: core::panicking::panic_fmt
       2: core::panicking::panic_bounds_check
       3: loom::rt::object::Ref<T>::set_action
       4: scoped_tls::ScopedKey<T>::with
       5: loom::rt::atomic::Atomic<T>::rmw
       6: loom::sync::atomic::int::AtomicU64::fetch_add
       7: lio::driver::Driver::reserve_driver_entry
       8: lio::accept
       9: <tokio::future::maybe_done::MaybeDone<Fut> as core::future::future::Future>::poll
      10: <core::future::poll_fn::PollFn<F> as core::future::future::Future>::poll
      11: test_accept::test_accept_concurrent::{{closure}}::{{closure}}
      12: tokio::runtime::scheduler::current_thread::Context::enter
      13: tokio::runtime::context::scoped::Scoped<T>::set
      14: tokio::runtime::scheduler::current_thread::CoreGuard::block_on
      15: tokio::runtime::context::runtime::enter_runtime
      16: lio::loom::test_utils::block_on
      17: core::ops::function::FnOnce::call_once{{vtable.shim}}
      18: generator::stack::StackBox<F>::call_once
      19: generator::detail::gen::gen_init_impl
      20: generator::detail::asm::gen_init
    note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

        FAIL [   4.259s] lio::test_accept test_accept_multiple
  stdout ───

    running 1 test
    ERROR generator::detail::gen: set panic inside generator
    test test_accept_multiple ... FAILED

    failures:

    failures:
        test_accept_multiple

    test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 4 filtered out; finished in 4.25s

  stderr ───

    thread 'test_accept_multiple' panicked at /Users/vt/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/loom-0.7.2/src/rt/object.rs:382:50:
    index out of bounds: the len is 0 but the index is 4
    stack backtrace:
       0: __rustc::rust_begin_unwind
       1: core::panicking::panic_fmt
       2: core::panicking::panic_bounds_check
       3: loom::rt::object::Ref<T>::set_action
       4: scoped_tls::ScopedKey<T>::with
       5: loom::rt::atomic::Atomic<T>::rmw
       6: loom::sync::atomic::int::AtomicU64::fetch_add
       7: lio::driver::Driver::reserve_driver_entry
       8: lio::accept
       9: <tokio::future::maybe_done::MaybeDone<Fut> as core::future::future::Future>::poll
      10: <core::future::poll_fn::PollFn<F> as core::future::future::Future>::poll
      11: test_accept::test_accept_multiple::{{closure}}::{{closure}}
      12: tokio::runtime::scheduler::current_thread::Context::enter
      13: tokio::runtime::context::scoped::Scoped<T>::set
      14: tokio::runtime::scheduler::current_thread::CoreGuard::block_on
      15: tokio::runtime::context::runtime::enter_runtime
      16: lio::loom::test_utils::block_on
      17: core::ops::function::FnOnce::call_once{{vtable.shim}}
      18: generator::stack::StackBox<F>::call_once
      19: generator::detail::gen::gen_init_impl
      20: generator::detail::asm::gen_init
    note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace

Reproduce instructions:
(If some tests run for more than 5s then kill, they deadlock)

$ git clone https://github.com/liten-rs/liten
$ cd liten/lio
$ RUSTFLAGS="--cfg loom" RUST_BACKTRACE=1 cargo nextest r --release