This commit is an implementation of [RFC 1681] which adds support to the
compiler for first-class user-define custom `#[derive]` modes with a far more
stable API than plugins have today.
[RFC 1681]: https://github.com/rust-lang/rfcs/blob/master/text/1681-macros-1.1.md
The main features added by this commit are:
* A new `rustc-macro` crate-type. This crate type represents one which will
provide custom `derive` implementations and perhaps eventually flower into the
implementation of macros 2.0 as well.
* A new `rustc_macro` crate in the standard distribution. This crate will
provide the runtime interface between macro crates and the compiler. The API
here is particularly conservative right now but has quite a bit of room to
expand into any manner of APIs required by macro authors.
* The ability to load new derive modes through the `#[macro_use]` annotations on
other crates.
All support added here is gated behind the `rustc_macro` feature gate, both for
the library support (the `rustc_macro` crate) as well as the language features.
There are a few minor differences from the implementation outlined in the RFC,
such as the `rustc_macro` crate being available as a dylib and all symbols are
`dlsym`'d directly instead of having a shim compiled. These should only affect
the implementation, however, not the public interface.
This commit also ended up touching a lot of code related to `#[derive]`, making
a few notable changes:
* Recognized derive attributes are no longer desugared to `derive_Foo`. Wasn't
sure how to keep this behavior and *not* expose it to custom derive.
* Derive attributes no longer have access to unstable features by default, they
have to opt in on a granular level.
* The `derive(Copy,Clone)` optimization is now done through another "obscure
attribute" which is just intended to ferry along in the compiler that such an
optimization is possible. The `derive(PartialEq,Eq)` optimization was also
updated to do something similar.
---
One part of this PR which needs to be improved before stabilizing are the errors
and exact interfaces here. The error messages are relatively poor quality and
there are surprising spects of this such as `#[derive(PartialEq, Eq, MyTrait)]`
not working by default. The custom attributes added by the compiler end up
becoming unstable again when going through a custom impl.
Hopefully though this is enough to start allowing experimentation on crates.io!
syntax-[breaking-change]
This commit is an implementation of [RFC 1513] which allows applications to
alter the behavior of panics at compile time. A new compiler flag, `-C panic`,
is added and accepts the values `unwind` or `panic`, with the default being
`unwind`. This model affects how code is generated for the local crate, skipping
generation of landing pads with `-C panic=abort`.
[RFC 1513]: https://github.com/rust-lang/rfcs/blob/master/text/1513-less-unwinding.md
Panic implementations are then provided by crates tagged with
`#![panic_runtime]` and lazily required by crates with
`#![needs_panic_runtime]`. The panic strategy (`-C panic` value) of the panic
runtime must match the final product, and if the panic strategy is not `abort`
then the entire DAG must have the same panic strategy.
With the `-C panic=abort` strategy, users can expect a stable method to disable
generation of landing pads, improving optimization in niche scenarios,
decreasing compile time, and decreasing output binary size. With the `-C
panic=unwind` strategy users can expect the existing ability to isolate failure
in Rust code from the outside world.
Organizationally, this commit dismantles the `sys_common::unwind` module in
favor of some bits moving part of it to `libpanic_unwind` and the rest into the
`panicking` module in libstd. The custom panic runtime support is pretty similar
to the custom allocator support with the only major difference being how the
panic runtime is injected (takes the `-C panic` flag into account).
This uncovered a lot of bugs in compiletest and also some shortcomings
of our existing JSON output. We had to add information to the JSON
output, such as suggested text and macro backtraces. We also had to fix
various bugs in the existing tests.
Joint work with jntrnr.
Compute `target_feature` from LLVM
This is a work-in-progress fix for #31662.
The logic that computes the target features from the command line has been replaced with queries to the `TargetMachine`.
This commit adds support in rustbuild for running all of the compiletest test
suites as part of `make check`. The `compiletest` program was moved to
`src/tools` (like `rustbook` and others) and is now just compiled like any other
old tool. Each test suite has a pretty standard set of dependencies and just
tweaks various parameters to the final compiletest executable.
Note that full support is lacking in terms of:
* Once a test suite has passed, that's not remembered. When a test suite is
requested to be run, it's always run.
* The arguments to compiletest probably don't work for every possible
combination of platforms and testing environments just yet. There will likely
need to be future updates to tweak various pieces here and there.
* Cross compiled test suites probably don't work just yet, support for that will
come in a follow-up patch.
emit (via debug!) scary message from `fn borrowck_mir` until basic
prototype is in place.
Gather children of move paths and set their kill bits in
dataflow. (Each node has a link to the child that is first among its
siblings.)
Hooked in libgraphviz based rendering, including of borrowck dataflow
state.
doing this well required some refactoring of the code, so I cleaned it
up more generally (adding comments to explain what its trying to do
and how it is doing it).
Update: this newer version addresses most review comments (at least
the ones that were largely mechanical changes), but I left the more
interesting revisions to separate followup commits (in this same PR).
typestrong const integers
~~It would be great if someone could run crater on this PR, as this has a high danger of breaking valid code~~ Crater ran. Good to go.
----
So this PR does a few things:
1. ~~const eval array values when const evaluating an array expression~~
2. ~~const eval repeat value when const evaluating a repeat expression~~
3. ~~const eval all struct and tuple fields when evaluating a struct/tuple expression~~
4. remove the `ConstVal::Int` and `ConstVal::Uint` variants and replace them with a single enum (`ConstInt`) which has variants for all integral types
* `usize`/`isize` are also enums with variants for 32 and 64 bit. At creation and various usage steps there are assertions in place checking if the target bitwidth matches with the chosen enum variant
5. enum discriminants (`ty::Disr`) are now `ConstInt`
6. trans has its own `Disr` type now (newtype around `u64`)
This obviously can't be done without breaking changes (the ones that are noticable in stable)
We could probably write lints that find those situations and error on it for a cycle or two. But then again, those situations are rare and really bugs imo anyway:
```rust
let v10 = 10 as i8;
let v4 = 4 as isize;
assert_eq!(v10 << v4 as usize, 160 as i8);
```
stops compiling because 160 is not a valid i8
```rust
struct S<T, S> {
a: T,
b: u8,
c: S
}
let s = S { a: 0xff_ff_ff_ffu32, b: 1, c: 0xaa_aa_aa_aa as i32 };
```
stops compiling because `0xaa_aa_aa_aa` is not a valid i32
----
cc @eddyb @pnkfelix
related: https://github.com/rust-lang/rfcs/issues/1071
Add a link validator to rustbuild
This commit was originally targeted at just adding a link checking script to the rustbuild system. This ended up snowballing a bit to extend rustbuild to be amenable to various tools we have as part of the build system in general.
There's a new `src/tools` directory which has a number of scripts/programs that are purely intended to be used as part of the build system and CI of this repository. This is currently inhabited by rustbook, the error index generator, and a new linkchecker script added as part of this PR. I suspect that more tools like compiletest, tidy scripts, snapshot scripts, etc will migrate their way into this directory over time.
The commit which adds the error index generator shows the steps necessary to add new tools to the build system, namely:
1. New steps are defined for building the tool and running the tool
2. The dependencies are configured
3. The steps are implemented
In terms of the link checker, these commits do a few things:
* A new `src/tools/linkchecker` script is added. This will read an entire documentation tree looking for broken relative links (HTTP links aren't followed yet).
* A large number of broken links throughout the documentation were fixed. Many of these were just broken when viewed from core as opposed to std, but were easily fixed.
* A few rustdoc bugs here and there were fixed
mk: Distribute fewer TARGET_CRATES
Right now everything in TARGET_CRATES is built by default for all non-fulldeps
tests and is distributed by default for all target standard library packages.
Currenly this includes a number of unstable crates which are rarely used such as
`graphviz` and `rbml`>
This commit trims down the set of `TARGET_CRATES`, moves a number of tests to
`*-fulldeps` as a result, and trims down the dependencies of libtest so we can
distribute fewer crates in the `rust-std` packages.
Right now everything in TARGET_CRATES is built by default for all non-fulldeps
tests and is distributed by default for all target standard library packages.
Currenly this includes a number of unstable crates which are rarely used such as
`graphviz` and `rbml`>
This commit trims down the set of `TARGET_CRATES`, moves a number of tests to
`*-fulldeps` as a result, and trims down the dependencies of libtest so we can
distribute fewer crates in the `rust-std` packages.
The `--disable-jemalloc` configure option has a failure mode where it will
create a distribution that is not compatible with other compilers. For example
the nightly for Linux will assume that it will link to jemalloc by default as
an allocator for executable crates. If, however, a standard library is used
which was built via `./configure --disable-jemalloc` then this will fail
because the jemalloc crate wasn't built.
While this seems somewhat reasonable as a niche situation, the same mechanism is
used for disabling jemalloc for platforms that just don't support it. For
example if the rumprun target is compiled then the sibiling Linux target *also*
doesn't have jemalloc. This is currently a problem for our cross-build nightlies
which build many targets. If rumprun is also built, it will disable jemalloc for
all targets, which isn't desired.
This commit moves the platform-specific disabling of jemalloc as hardcoded logic
into the makefiles that is scoped per-platform. This way when configuring
multiple targets **without the `--disable-jemalloc` option specified** all
targets will get jemalloc as they should.
This is because the tool compiler passes the name of the tool
as a command line `--cfg`. The improved session config parser
is stricter and no longer permits invalid meta items (such as
"error-index-generator").
When building with Cargo we need to detect `feature = "jemalloc"` to enable
jemalloc, so propagate this same change to the build system to pass the right
`--cfg` argument.
This aligns with unicode recommendations and should be stable for all future
unicode releases. See http://unicode.org/reports/tr31/#R3.
This renames `libsyntax::lexer::is_whitespace` to `is_pattern_whitespace`
so potentially breaks users of libsyntax.
this makes sure the checks run before typeck (which might use the constant or const
function to calculate an array length) and gives prettier error messages in case of for
loops and such (since they aren't expanded yet).
Use arena allocation instead of reference counting for `Module`s to fix memory leaks from `Rc` cycles.
A module references its module children and its import resolutions, and an import resolution references the module defining the imported name, so there is a cycle whenever a module imports something from an ancestor module.
For example,
```rust
mod foo { // `foo` references `bar`.
fn baz() {}
mod bar { // `bar` references the import.
use foo::baz; // The import references `foo`.
}
}
```
With this commit, metadata encoding and decoding can make use of
thread-local encoding and decoding contexts. These allow implementers
of serialize::Encodable and Decodable to access information and
datastructures that would otherwise not be available to them. For
example, we can automatically translate def-id and span information
during decoding because the decoding context knows which crate the
data is decoded from. Or it allows to make ty::Ty decodable because
the context has access to the ty::ctxt that is needed for creating
ty::Ty instances.
* Delete `sys::unix::{c, sync}` as these are now all folded into libc itself
* Update all references to use `libc` as a result.
* Update all references to the new flat namespace.
* Moves all windows bindings into sys::c
