E0277 rust type_error ai_generated true

error[E0277]: `Rc<RefCell<dyn Trait>>` cannot be sent between threads safely

ID: rust/e0277-send-not-satisfied-for-rc

Also available as: JSON · Markdown · 中文
85%Fix Rate
85%Confidence
1Evidence
2023-06-15First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
rustc 1.68 active — — —
rustc 1.75 active — — —
rustc 1.82 active — — —

Root Cause

Rc is not Send because it uses reference counting without atomic operations; cross-thread use causes data races.

generic

中文

Rc 使用非原子引用计数，跨线程使用会导致数据竞争，因此未实现 Send。

Official Documentation

https://doc.rust-lang.org/stable/std/marker/trait.Send.html

Workarounds

  1. 90% success Replace Rc with Arc (atomic reference counting) and use Arc<Mutex<T>> or Arc<RwLock<T>> for interior mutability. 
    Replace Rc with Arc (atomic reference counting) and use Arc<Mutex<T>> or Arc<RwLock<T>> for interior mutability.
  2. 75% success Use `std::sync::Mutex<RefCell<dyn Trait>>` or `parking_lot::Mutex` if you must keep Rc, but prefer Arc. 
    Use `std::sync::Mutex<RefCell<dyn Trait>>` or `parking_lot::Mutex` if you must keep Rc, but prefer Arc.

中文步骤

  1. 将 Rc 替换为 Arc（原子引用计数），并使用 Arc<Mutex<T>> 或 Arc<RwLock<T>> 实现内部可变性。
  2. 使用 `std::sync::Mutex<RefCell<dyn Trait>>` 或 `parking_lot::Mutex` 如果必须保留 Rc，但推荐使用 Arc。

Dead Ends

Common approaches that don't work:

  1. 70% fail

    Mutex<Arc<RefCell<...>>> adds overhead and doesn't solve the fundamental Rc issue; use Arc instead.

  2. 90% fail

    Deriving Clone doesn't change thread safety; the compiler still requires Send on the inner type.