This type has been superseded by Arc<Unsafe<T>>. The UnsafeArc type is a relic
of an era that has long since past, and with the introduction of liballoc the
standard library is able to use the Arc smart pointer. With little need left for
UnsafeArc, it was removed.
All existing code using UnsafeArc should either be reevaluated to whether it can
use only Arc, or it should transition to Arc<Unsafe<T>>
[breaking-change]
This commit revisits the `cast` module in libcore and libstd, and scrutinizes
all functions inside of it. The result was to remove the `cast` module entirely,
folding all functionality into the `mem` module. Specifically, this is the fate
of each function in the `cast` module.
* transmute - This function was moved to `mem`, but it is now marked as
#[unstable]. This is due to planned changes to the `transmute`
function and how it can be invoked (see the #[unstable] comment).
For more information, see RFC 5 and #12898
* transmute_copy - This function was moved to `mem`, with clarification that is
is not an error to invoke it with T/U that are different
sizes, but rather that it is strongly discouraged. This
function is now #[stable]
* forget - This function was moved to `mem` and marked #[stable]
* bump_box_refcount - This function was removed due to the deprecation of
managed boxes as well as its questionable utility.
* transmute_mut - This function was previously deprecated, and removed as part
of this commit.
* transmute_mut_unsafe - This function doesn't serve much of a purpose when it
can be achieved with an `as` in safe code, so it was
removed.
* transmute_lifetime - This function was removed because it is likely a strong
indication that code is incorrect in the first place.
* transmute_mut_lifetime - This function was removed for the same reasons as
`transmute_lifetime`
* copy_lifetime - This function was moved to `mem`, but it is marked
`#[unstable]` now due to the likelihood of being removed in
the future if it is found to not be very useful.
* copy_mut_lifetime - This function was also moved to `mem`, but had the same
treatment as `copy_lifetime`.
* copy_lifetime_vec - This function was removed because it is not used today,
and its existence is not necessary with DST
(copy_lifetime will suffice).
In summary, the cast module was stripped down to these functions, and then the
functions were moved to the `mem` module.
transmute - #[unstable]
transmute_copy - #[stable]
forget - #[stable]
copy_lifetime - #[unstable]
copy_mut_lifetime - #[unstable]
[breaking-change]
for `~str`/`~[]`.
Note that `~self` still remains, since I forgot to add support for
`Box<self>` before the snapshot.
How to update your code:
* Instead of `~EXPR`, you should write `box EXPR`.
* Instead of `~TYPE`, you should write `Box<Type>`.
* Instead of `~PATTERN`, you should write `box PATTERN`.
[breaking-change]
This removes all resizability support for ~[T] vectors in preparation of DST.
The only growable vector remaining is Vec<T>. In summary, the following methods
from ~[T] and various functions were removed. Each method/function has an
equivalent on the Vec type in std::vec unless otherwise stated.
* slice::OwnedCloneableVector
* slice::OwnedEqVector
* slice::append
* slice::append_one
* slice::build (no replacement)
* slice::bytes::push_bytes
* slice::from_elem
* slice::from_fn
* slice::with_capacity
* ~[T].capacity()
* ~[T].clear()
* ~[T].dedup()
* ~[T].extend()
* ~[T].grow()
* ~[T].grow_fn()
* ~[T].grow_set()
* ~[T].insert()
* ~[T].pop()
* ~[T].push()
* ~[T].push_all()
* ~[T].push_all_move()
* ~[T].remove()
* ~[T].reserve()
* ~[T].reserve_additional()
* ~[T].reserve_exect()
* ~[T].retain()
* ~[T].set_len()
* ~[T].shift()
* ~[T].shrink_to_fit()
* ~[T].swap_remove()
* ~[T].truncate()
* ~[T].unshift()
* ~str.clear()
* ~str.set_len()
* ~str.truncate()
Note that no other API changes were made. Existing apis that took or returned
~[T] continue to do so.
[breaking-change]
Someone reading the docs won't know what the types of various things
are, so this adds them in a few meaningful places to help with
comprehension.
cc #13423.
Summary:
So far, we've used the term POD "Plain Old Data" to refer to types that
can be safely copied. However, this term is not consistent with the
other built-in bounds that use verbs instead. This patch renames the Pod
kind into Copy.
RFC: 0003-opt-in-builtin-traits
Test Plan: make check
Reviewers: cmr
Differential Revision: http://phabricator.octayn.net/D3
This needs to be removed as part of removing `~[T]`. Partial type hints
are now allowed, and will remove the need to add a version of this
method for `Vec<T>`. For now, this involves a few workarounds for
partial type hints not completely working.
In Rust, the strongest guarantee that `&mut` provides is that the memory
pointed to is *not aliased*, whereas `&`'s guarantees are much weaker:
that the value can be aliased, and may be mutated under proper precautions
(interior mutability).
Our atomics though use `&mut` for mutation even while creating multiple
aliases, so this changes them to use 'interior mutability', mutating
through immutable references.
This adds lots of docs to the atomics module. Two of the examples
are using the future atomics API (relying on `Share`) and are ignored temporarily.
I discovered a bug in the way AtomicBool's fetch_nand method is
implemented and fixed it by using the correct value for `true`.
I also fixed the implementation of AcqRel fences (it was only doing
a release barrier), and made a "relaxed" fence a failure.
This adds lots of docs to the atomics module. Two of the examples
are using the future atomics API and are ignored temporarily.
I discovered a bug in the way AtomicBool's fetch_nand method is
implemented and fixed it by using the correct value for `true`.
I also fixed the implementation of AcqRel fences (it was only doing
a release barrier), and made a "relaxed" fence a failure.
Formatting via reflection has been a little questionable for some time now, and
it's a little unfortunate that one of the standard macros will silently use
reflection when you weren't expecting it. This adds small bits of code bloat to
libraries, as well as not always being necessary. In light of this information,
this commit switches assert_eq!() to using {} in the error message instead of
{:?}.
In updating existing code, there were a few error cases that I encountered:
* It's impossible to define Show for [T, ..N]. I think DST will alleviate this
because we can define Show for [T].
* A few types here and there just needed a #[deriving(Show)]
* Type parameters needed a Show bound, I often moved this to `assert!(a == b)`
* `Path` doesn't implement `Show`, so assert_eq!() cannot be used on two paths.
I don't think this is much of a regression though because {:?} on paths looks
awful (it's a byte array).
Concretely speaking, this shaved 10K off a 656K binary. Not a lot, but sometime
significant for smaller binaries.
This is a ubiquitous type in concurrent code, and the assertions are causing
significant code bloat for simple operations such as reading the pointer
(injecting a failure point, etc).
I am testing executable sizes with no I/O implementations (everything stubbed
out to return nothing), and this took the size of a libnative executable from
328K to 207K (37% reduction in size), so I think that this is one assertion
that's well worth configuring off for now.
This, the Nth rewrite of channels, is not a rewrite of the core logic behind
channels, but rather their API usage. In the past, we had the distinction
between oneshot, stream, and shared channels, but the most recent rewrite
dropped oneshots in favor of streams and shared channels.
This distinction of stream vs shared has shown that it's not quite what we'd
like either, and this moves the `std::comm` module in the direction of "one
channel to rule them all". There now remains only one Chan and one Port.
This new channel is actually a hybrid oneshot/stream/shared channel under the
hood in order to optimize for the use cases in question. Additionally, this also
reduces the cognitive burden of having to choose between a Chan or a SharedChan
in an API.
My simple benchmarks show no reduction in efficiency over the existing channels
today, and a 3x improvement in the oneshot case. I sadly don't have a
pre-last-rewrite compiler to test out the old old oneshots, but I would imagine
that the performance is comparable, but slightly slower (due to atomic reference
counting).
This commit also brings the bonus bugfix to channels that the pending queue of
messages are all dropped when a Port disappears rather then when both the Port
and the Chan disappear.
Beforehand, using a concurrent queue always mandated that the "shared state" be
stored internally to the queues in order to provide a safe interface. This isn't
quite as flexible as one would want in some circumstances, so instead this
commit moves the queues to not containing the shared state.
The queues no longer have a "default useful safe" interface, but rather a
"default safe" interface (minus the useful part). The queues have to be shared
manually through an Arc or some other means. This allows them to be a little
more flexible at the cost of a usability hindrance.
I plan on using this new flexibility to upgrade a channel to a shared channel
seamlessly.
This allows patch adds a new arc type that allows for creation of copy-on-write data structures. The idea is that it is safe to mutate any data structure as long as it has only one reference to it. If there are multiple, it requires cloning of the data structure before mutation is possible.
The patch adds a `pow` function for types implementing `One`, `Mul` and
`Clone` trait.
The patch also renames f32 and f64 pow into powf in order to still have
a way to easily have float powers. It uses llvms intrinsics.
The pow implementation for all num types uses the exponentiation by
square.
Fixes bug #11499
The methods contained in `std::num::{Algebraic, Trigonometric, Exponential, Hyperbolic}` have now been moved into `std::num::Real`. This is part of an ongoing effort to simplify `std::num` (see issue #10387).
`std::num::RealExt` has also been removed from the prelude because it is not a commonly used trait.
* vec::raw::to_ptr is gone
* Pausible => Pausable
* Removing @
* Calling the main task "<main>"
* Removing unused imports
* Removing unused mut
* Bringing some libextra tests up to date
* Allowing compiletest to work at stage0
* Fixing the bootstrap-from-c rmake tests
* assert => rtassert in a few cases
* printing to stderr instead of stdout in fail!()
Note that this removes a number of run-pass tests which are exercising behavior
of the old runtime. This functionality no longer exists and is thoroughly tested
inside of libgreen and libnative. There isn't really the notion of "starting the
runtime" any more. The major notion now is "bootstrapping the initial task".
For now, this moves the following modules to std::sync
* UnsafeArc (also removed unwrap method)
* mpsc_queue
* spsc_queue
* atomics
* mpmc_bounded_queue
* deque
We may want to remove some of the queues, but for now this moves things out of
std::rt into std::sync
