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]
Also move prelude explanation to the prelude module.
This tries to provide a guide to what's in the standard library, organized bottom up from primitives to I/O.
This currently requires linking against a library like libquadmath (or
libgcc), because compiler-rt barely has any support for this and most
hardware does not yet have 128-bit precision floating point. For this
reason, it's currently hidden behind a feature gate.
When compiler-rt is updated to trunk, some tests can be added for
constant evaluation since there will be support for the comparison
operators.
Closes#13381
rustc: feature-gate `concat_idents!`.
concat_idents! is not as useful as it could be, due to macros only being
allowed in limited places, and hygiene, so lets feature gate it until we
make a decision about it.
cc #13294
concat_idents! is not as useful as it could be, due to macros only being
allowed in limited places, and hygiene, so lets feature gate it until we
make a decision about it.
cc #13294
Closes#13285 (rustc: Stop using LLVMGetSectionName)
Closes#13280 (std: override clone_from for Vec.)
Closes#13277 (serialize: add a few missing pubs to base64)
Closes#13275 (Add and remove some ignore-win32 flags)
Closes#13273 (Removed managed boxes from libarena.)
Closes#13270 (Minor copy-editing for the tutorial)
Closes#13267 (fix Option<~ZeroSizeType>)
Closes#13265 (Update emacs mode to support new `#![inner(attribute)]` syntax.)
Closes#13263 (syntax: Remove AbiSet, use one Abi)
A vector can reuse its allocation (and the allocations/resources of any
contained values) when cloning into an already-instantiated vector, so
we might as well do so.
The `Float` trait methods will be usable as functions via UFCS, and
we came to a consensus to remove duplicate functions like this a long
time ago.
It does still make sense to keep the duplicate functions when the trait
methods are static, unless the decision to leave out the in-scope trait
name resolution for static methods changes.
This is an implementation detail of the `f32` and `f64` modules and it
should not be public. It renames many functions and leaves out any
provided by LLVM intrinsics, so it is not a sensible binding to the C
standard library's math library and will never be a stable target.
This also removes the abuse of link_name so that this can be switched to
using automatically generated definitions in the future. This also
removes the `scalbn` binding as it is equivalent to `ldexp` when
`FLT_RADIX` is 2, which must always be true for Rust.
This is the final nail in the coffin for the crate map. The `start` function for
libgreen now has a new added parameter which is the event loop factory instead
of inferring it from the crate map. The two current valid values for this
parameter are `green::basic::event_loop` and `rustuv::event_loop`.
The compiler will no longer inject libgreen as the default runtime for rust
programs, this commit switches it over to libnative by default. Now that
libnative has baked for some time, it is ready enough to start getting more
serious usage as the default runtime for rustc generated binaries.
We've found that there isn't really a correct decision in choosing a 1:1 or M:N
runtime as a default for all applications, but it seems that a larger number of
programs today would work more reasonable with a native default rather than a
green default.
With this commit come a number of bugfixes:
* The main native task is now named "<main>"
* The main native task has the stack bounds set up properly
* #[no_uv] was renamed to #[no_start]
* The core-run-destroy test was rewritten for both libnative and libgreen and
one of the tests was modified to be more robust.
* The process-detach test was locked to libgreen because it uses signal handling
`Share` implies that all *reachable* content is *threadsafe*.
Threadsafe is defined as "exposing no operation that permits a data race if multiple threads have access to a &T pointer simultaneously". (NB: the type system should guarantee that if you have access to memory via a &T pointer, the only other way to gain access to that memory is through another &T pointer)...
Fixes#11781
cc #12577
What this PR will do
================
- [x] Add Share kind and
- [x] Replace usages of Freeze with Share in bounds.
- [x] Add Unsafe<T> #12577
- [x] Forbid taking the address of a immutable static item with `Unsafe<T>` interior
What's left to do in a separate PR (after the snapshot)?
===========================================
- Remove `Freeze` completely
This commit moves all logging out of the standard library into an external
crate. This crate is the new crate which is responsible for all logging macros
and logging implementation. A few reasons for this change are:
* The crate map has always been a bit of a code smell among rust programs. It
has difficulty being loaded on almost all platforms, and it's used almost
exclusively for logging and only logging. Removing the crate map is one of the
end goals of this movement.
* The compiler has a fair bit of special support for logging. It has the
__log_level() expression as well as generating a global word per module
specifying the log level. This is unfairly favoring the built-in logging
system, and is much better done purely in libraries instead of the compiler
itself.
* Initialization of logging is much easier to do if there is no reliance on a
magical crate map being available to set module log levels.
* If the logging library can be written outside of the standard library, there's
no reason that it shouldn't be. It's likely that we're not going to build the
highest quality logging library of all time, so third-party libraries should
be able to provide just as high-quality logging systems as the default one
provided in the rust distribution.
With a migration such as this, the change does not come for free. There are some
subtle changes in the behavior of liblog vs the previous logging macros:
* The core change of this migration is that there is no longer a physical
log-level per module. This concept is still emulated (it is quite useful), but
there is now only a global log level, not a local one. This global log level
is a reflection of the maximum of all log levels specified. The previously
generated logging code looked like:
if specified_level <= __module_log_level() {
println!(...)
}
The newly generated code looks like:
if specified_level <= ::log::LOG_LEVEL {
if ::log::module_enabled(module_path!()) {
println!(...)
}
}
Notably, the first layer of checking is still intended to be "super fast" in
that it's just a load of a global word and a compare. The second layer of
checking is executed to determine if the current module does indeed have
logging turned on.
This means that if any module has a debug log level turned on, all modules
with debug log levels get a little bit slower (they all do more expensive
dynamic checks to determine if they're turned on or not).
Semantically, this migration brings no change in this respect, but
runtime-wise, this will have a perf impact on some code.
* A `RUST_LOG=::help` directive will no longer print out a list of all modules
that can be logged. This is because the crate map will no longer specify the
log levels of all modules, so the list of modules is not known. Additionally,
warnings can no longer be provided if a malformed logging directive was
supplied.
The new "hello world" for logging looks like:
#[phase(syntax, link)]
extern crate log;
fn main() {
debug!("Hello, world!");
}
This commit shreds all remnants of libextra from the compiler and standard
distribution. Two modules, c_vec/tempfile, were moved into libstd after some
cleanup, and the other modules were moved to separate crates as seen fit.
Closes#8784Closes#12413Closes#12576
This functionality is not super-core and so doesn't need to be included
in std. It's possible that std may need rand (it does a little bit now,
for io::test) in which case the functionality required could be moved to
a secret hidden module and reexposed by librand.
Unfortunately, using #[deprecated] here is hard: there's too much to
mock to make it feasible, since we have to ensure that programs still
typecheck to reach the linting phase.
It is often convenient to have forms of weak linkage or other various types of
linkage. Sadly, just using these flavors of linkage are not compatible with
Rust's typesystem and how it considers some pointers to be non-null.
As a compromise, this commit adds support for weak linkage to external symbols,
but it requires that this is only placed on extern statics of type `*T`.
Codegen-wise, we get translations like:
// rust code
extern {
#[linkage = "extern_weak"]
static foo: *i32;
}
// generated IR
@foo = extern_weak global i32
@_some_internal_symbol = internal global *i32 @foo
All references to the rust value of `foo` then reference `_some_internal_symbol`
instead of the symbol `_foo` itself. This allows us to guarantee that the
address of `foo` will never be null while the value may sometimes be null.
An example was implemented in `std::rt::thread` to determine if
`__pthread_get_minstack()` is available at runtime, and a test is checked in to
use it for a static value as well. Function pointers a little odd because you
still need to transmute the pointer value to a function pointer, but it's
thankfully better than not having this capability at all.
