Trait shredder::marker::GcDrop[−][src]

pub unsafe trait GcDrop { }
Expand description

A marker trait that the destructor of this data can be safely run in the background thread

Basically it asserts three things

  1. Any thread can drop this data (It is Send, or !Send purely because it contains a Gc, or it is !Send but you know that any thread dropping this data is safe.)
  2. This data does not own a AtomicGc or DerefGc
  3. This data is 'static, or you can guarantee that it’s safe to drop it after its lifetime has ended.

This trait is structural, although I’m sure with some crazy unsafe code you could break that assumption.

The Scan derive will automatically generate a GcDrop impl for you. For example:

use shredder::Scan;

// SomeGcDropType will implement `GcDrop` as well as `Scan` and `GcSafe`
#[derive(Scan)]
struct SomeGcDropType {
    random_data: u32
}

If this is causing you problems you can turn it off with the #[shredder(cant_drop)] annotation. For example:

use shredder::atomic::AtomicGc;
use shredder::Scan;

// CantImplGcDrop will not get a `GcDrop` implementation
#[derive(Scan)]
#[shredder(cant_drop)] // <- This allows this code to compile
struct CantImplGcDrop {
    some_non_gc_drop_type: AtomicGc<u32>
}

Implementations on Foreign Types

Implementors