Otherwise, run-pass/deriving-primitive.rs breaks on 32-bit platforms,
because `int::min_value` is `0xffffffff7fffffff` when evaluated for the
discriminant declaration.
Not only can discriminants be smaller than int now, but they can be
larger than int on 32-bit targets. This has obvious implications for the
reflection interface. Without this change, things fail with LLVM
assertions when we try to "extend" i64 to i32.
The variant used in debug-info/method-on-enum.rs had its layout changed
by the smaller discriminant, so that the `u32` no longer overlaps both
of the `u16`s, and thus the debugger is printing partially uninitialized
data when it prints the wrong variant.
Thus, the test runner is modified to accept wildcards (using a string
that should be unlikely to occur literally), to allow for this.
Note that raising an error during trans doesn't stop the compile or cause
rustc to exit with a failure status, currently, so this is of more than
cosmetic importance.
Allows an enum with a discriminant to use any of the primitive integer
types to store it. By default the smallest usable type is chosen, but
this can be overridden with an attribute: `#[repr(int)]` etc., or
`#[repr(C)]` to match the target's C ABI for the equivalent C enum.
This commit breaks a few things, due to transmutes that now no longer
match in size, or u8 enums being passed to C that expects int, or
reflection; later commits on this branch fix them.
There are a few reasons that this is a desirable move to take:
1. Proof of concept that a third party event loop is possible
2. Clear separation of responsibility between rt::io and the uv-backend
3. Enforce in the future that the event loop is "pluggable" and replacable
Here's a quick summary of the points of this pull request which make this
possible:
* Two new lang items were introduced: event_loop, and event_loop_factory.
The idea of a "factory" is to define a function which can be called with no
arguments and will return the new event loop as a trait object. This factory
is emitted to the crate map when building an executable. The factory doesn't
have to exist, and when it doesn't then an empty slot is in the crate map and
a basic event loop with no I/O support is provided to the runtime.
* When building an executable, then the rustuv crate will be linked by default
(providing a default implementation of the event loop) via a similar method to
injecting a dependency on libstd. This is currently the only location where
the rustuv crate is ever linked.
* There is a new #[no_uv] attribute (implied by #[no_std]) which denies
implicitly linking to rustuv by default
Closes#5019
This is, I think, the minimal change required. I would have included a test but as far as I can tell there is currently no way to precisely test that the span for an error underlines the correct word. I did verify it manually.
Used nowhere, and these are likely incorrect anyway: self needs to be
dereferenced once more otherwise the method calls will be reusing the
current impl... bam! Infinite recursion.
LLVM is unable to determine this for most cases.
http://llvm-reviews.chandlerc.com/D2034 needs to land upstream before
this is going to have an effect. It's harmless to start generating the
expect hint now.
r? @metajack When invoked with the --rust-path-hack flag, rustpkg was correctly building
the package into the default workspace (and not into the build/ subdirectory of the
parent directory of the source directory), but not correctly putting the output
for any dependencies into the default workspace as well.
Spotted by Jack.
Primarily this makes the Scheduler and all of its related interfaces public. The
reason for doing this is that currently any extern event loops had no access to
the scheduler at all. This allows third-party event loops to manipulate the
scheduler, along with allowing the uv event loop to live inside of its own
crate.
These methods are all excellent candidates for default methods, so there's no need to require extra imports of various traits. Additionally, this was able to remove all the weird underscores after the method names. Yay!
This drops more of the old C++ runtime to rather be written in rust. A few
features were lost along the way, but hopefully not too many. The main loss is
that there are no longer backtraces associated with allocations (rust doesn't
have a way of acquiring those just yet). Other than that though, I believe that
the rest of the debugging utilities made their way over into rust.
Closes#8704
# Summary
This PR allows the cause of a failure to be received in a task's future result and as the `Err` case of `task::try`, and also implements dynamic typing in form of an `Any` trait.
# Task failure
- `fail!` and related macros now accept 5 kinds of types: `~str`, `&'static str`, `std::send_str::SendStr`, `~std::any::Any` and `~T` where `T: Any + Send + 'static`
- `std::task::TaskResult` got transformed into an internal enum `std::rt::task::UnwindResult`, and it's `Failure` variant now contains a value of enum type `UnwindReason`:
- `UnwindReasonStr(SendStr)` maps to failing with a value of type `~str`, `&'static str` or `SendStr`.
- `UnwindReasonAny(~Any)` maps to failing with an `~Any` or `~T` with `T: Send + 'static`.
- `UnwindReasonLinked` maps to failing because the task got killed by linked failure.
- Instead, `std::task::TaskResult` is now a typedef for `Result<(), ~Any>`, and both `TaskBuilder`'s `future_result()` and `task::try` now work with a value of this type.
- `future_result()` no longer returns a `Port<TaskResult>`, instead it returns a wrapper `TaskResultPort` that implements `GenericPort` and `Peekable`, and which lazily allocates a `~` box and casts to `~Any` in case of failure with a `SendStr` or linked failure (for the latter case a unit struct `LinkedFailure` got added.)
- Because `fail!` collapses both `~str` and `&'static str` into a `SendStr`, checking if a task error value is a string will just require a `.is::<SendStr>()` check, with `~str` and `&'static str` only being possible in case of an explicit `fail!(~~"...")` or `fail!(~ (&"...") as ~Any)`:
# Any
- In order to allow failing with arbitrary data, the `Any` trait got implemented.
- It is being used in form of a trait object, usually `~Any` or `&Any`.
- `&Any`, `~Any` and `&mut Any` have a few extension methods implemented on them:
- `is<T>(self) -> bool` returns true if the `Any` object contains type `T`
- `as_ref<T>(self) -> Option<&T>` returns a reference to the contained type, if it is `T`
- `as_mut<T>(self) -> Option<&mut T>` returns a mutable reference to the contained type, if it is `T`
- `move<T>(self) -> Option<~T>` allows to get the `~T` out of an `~Any` again.
- `Any` currently uses type descriptors as a type id for comparisons, which is
- not reliable, as it is not guaranteed that every type has only one type descriptor.
- But safe, as no two types share the same type descriptor.
- The implementation also a few `transmute`s, mostly to cast a `*Void` of the wrapped type into it's actual type `&T`, `&mut T` or `~T`.
# Other changes
- `std::unstable::UnsafeArc::try_unwrap` no longer uses `Either`, bringing us one step closer to removing that type.
- A few of the touched modules got their import lines sorted.
- A few stylistic cleanups here and there.
