This commit stabilizes the `std::sync::atomics` module, renaming it to
`std::sync::atomic` to match library precedent elsewhere, and tightening
up behavior around incorrect memory ordering annotations.
The vast majority of the module is now `stable`. However, the
`AtomicOption` type has been deprecated, since it is essentially unused
and is not truly a primitive atomic type. It will eventually be replaced
by a higher-level abstraction like MVars.
Due to deprecations, this is a:
[breaking-change]
This PR is the outcome of the library stabilization meeting for the
`liballoc::owned` and `libcore::cell` modules.
Aside from the stability attributes, there are a few breaking changes:
* The `owned` modules is now named `boxed`, to better represent its
contents. (`box` was unavailable, since it's a keyword.) This will
help avoid the misconception that `Box` plays a special role wrt
ownership.
* The `AnyOwnExt` extension trait is renamed to `BoxAny`, and its `move`
method is renamed to `downcast`, in both cases to improve clarity.
* The recently-added `AnySendOwnExt` extension trait is removed; it was
not being used and is unnecessary.
[breaking-change]
This commit is the final step in the libstd facade, #13851. The purpose of this
commit is to move libsync underneath the standard library, behind the facade.
This will allow core primitives like channels, queues, and atomics to all live
in the same location.
There were a few notable changes and a few breaking changes as part of this
movement:
* The `Vec` and `String` types are reexported at the top level of libcollections
* The `unreachable!()` macro was copied to libcore
* The `std::rt::thread` module was moved to librustrt, but it is still
reexported at the same location.
* The `std::comm` module was moved to libsync
* The `sync::comm` module was moved under `sync::comm`, and renamed to `duplex`.
It is now a private module with types/functions being reexported under
`sync::comm`. This is a breaking change for any existing users of duplex
streams.
* All concurrent queues/deques were moved directly under libsync. They are also
all marked with #![experimental] for now if they are public.
* The `task_pool` and `future` modules no longer live in libsync, but rather
live under `std::sync`. They will forever live at this location, but they may
move to libsync if the `std::task` module moves as well.
[breaking-change]
