Stabilize core::future::{pending,ready}
This PR stabilizes `core::future::{pending,ready}`, tracking issue https://github.com/rust-lang/rust/issues/70921.
## Motivation
These functions have been on nightly for three months now, and have lived as part of the futures ecosystem for several years. In that time these functions have undergone several iterations, with [the `async-std` impls](https://docs.rs/async-std/1.6.2/async_std/future/index.html) probably diverging the most (using `async fn`, which in hindsight was a mistake).
It seems the space around these functions has been _thoroughly_ explored over the last couple of years, and the ecosystem has settled on the current shape of the functions. It seems highly unlikely we'd want to make any further changes to these functions, so I propose we stabilize.
## Implementation notes
This stabilization PR was fairly straightforward; this feature has already thoroughly been reviewed by the libs team already in https://github.com/rust-lang/rust/pull/70834. So all this PR does is remove the feature gate.
Add `peek` and `peek_from` to `UnixStream` and `UnixDatagram`
This is my first PR, so I'm sure I've done some things wrong.
This PR:
* adds `peek` function to `UnixStream`;
* adds `peek` and `peek_from` to `UnixDatagram`;
* moves `UnixDatagram::recv_from` implementation to a private function `recv_from_flags`, as `peek_from` uses the same code, just with different flags.
I've taken the documentation from `TcpStream` and `UdpStream`, so it may or may not make sense (I'm bad with english words).
Also, I'm not sure what I should write in the `unstable` attribute, so I've made up the name and set the issue to "none".
Closes#68565.
Give better diagnostic when using a private tuple struct constructor
Fixes#75907
Some notes:
1. This required some deep changes, including removing a Copy impl for PatKind. If some tests fail, I would still appreciate review on the overall approach
2. this only works with basic patterns (no wildcards for example), and fails if there is any problems getting the visibility of the fields (i am not sure what the failure that can happen in resolve_visibility_speculative, but we check the length of our fields in both cases against each other, so if anything goes wrong, we fall back to the worse error. This could be extended to more patterns
3. this does not yet deal with #75906, but I believe it will be similar
4. let me know if you want more tests
5. doesn't yet at the suggestion that `@yoshuawuyts` suggested at the end of their issue, but that could be added relatively easily (i believe)
rustbuild: avoid trying to inversely cross-compile for build triple from host triples
This changes rustbuild's cross compilation logic to better match what users expect,
particularly, avoiding trying to inverse cross-compile for the build triple from host triples.
That is, if build=A, host=B, target=B, we do not want to try and compile for A from B.
Indeed, the only "known to run" triple when cross-compiling is the build triple A.
When testing for a particular target we need to be able to run binaries compiled for
that target though.
The last commit also modifies the default set of host/target triples to avoid producing
needless artifacts for the build triple:
The new behavior is to respect --host and --target when passed as the *only*
configured triples (no triples are implicitly added). The default for --host is
the build triple, and the default for --target is the host triple(s), either
configured or the default build triple.
Fixes#76333
r? `@alexcrichton` if possible, otherwise we'll need to hunt down a reviewer
Previously, the CLI --target/--host definitions and configured options differed
in their effect: when setting these on the CLI, only the passed triples would be
compiled for, while in config.toml we would also compile for the build triple
and any host triples. This is needlessly confusing; users expect --target and
--host to be identical to editing the configuration file.
The new behavior is to respect --host and --target when passed as the *only*
configured triples (no triples are implicitly added). The default for --host is
the build triple, and the default for --target is the host triple(s), either
configured or the default build triple.
rustc is a natively cross-compiling compiler, and generally none of our steps
should care whether they are using a compiler built of triple A or B, just the
--target directive being passed to the running compiler. e.g., when building for
some target C, you don't generally want to build two stds: one with a host A
compiler and the other with a host B compiler. Just one std is sufficient.
Only copy LLVM into rust-dev with internal LLVM
This avoids needing to figure out where to locate each of the components with an
external LLVM. This component isn't manifested for rustup consumption and
generally shouldn't matter for anyone except Rust's CI, so it is fine for it to not be
complete elsewhere.
Fixes#76572.
r? `@alexcrichton`
Add help note when using type in place of const
This adds a small help note when it might be possible that wrapping a parameter in braces might resolve the issue of having a type where a const was expected.
Currently, I am displaying the `HirId`, and I'm not particularly sure where to get the currently displayed path(?).
r? `@lcnr`
rustbuild: Do not use `rust-mingw` component when bootstrapping windows-gnu targets
Addresses https://github.com/rust-lang/rust/pull/76326#issuecomment-687273473 (ancient `x86_64-w64-mingw32-gcc` is selected as a linker wrapper, which is not usable in `use_lld=true` mode).
Perhaps the comment about incompatible mingw was true in the past, but many things changed since then.
With this change I was able to build everything successfully locally using a newer mingw toolchain, if it passes through the older toolchain on CI, then it should be good, I think.
Attach tokens to all AST types used in `Nonterminal`
We perform token capturing when we have outer attributes (for nonterminals that support attributes - e.g. `Stmt`), or when we parse a `Nonterminal` for a `macro_rules!` argument. The full list of `Nonterminals` affected by this PR is:
* `NtBlock`
* `NtStmt`
* `NtTy`
* `NtMeta`
* `NtPath`
* `NtVis`
* `NtLiteral`
Of these nonterminals, only `NtStmt` and `NtLiteral` (which is actually just an `Expr`), support outer attributes - the rest only ever have token capturing perform when they match a `macro_rules!` argument.
This makes progress towards solving https://github.com/rust-lang/rust/issues/43081 - we now collect tokens for everything that might need them. However, we still need to handle `#[cfg]`, inner attributes, and misc pretty-printing issues (e.g. #75734)
I've separated the changes into (mostly) independent commits, which could be split into individual PRs for each `Nonterminal` variant. The purpose of having them all in one PR is to do a single Crater run for all of them.
Most of the changes in this PR are trivial (adding `tokens: None` everywhere we construct the various AST structs). The significant changes are:
* `ast::Visibility` is changed from `type Visibility = Spanned<VisibilityKind>` to a `struct Visibility { kind, span, tokens }`.
* `maybe_collect_tokens` is made generic, and used for both `ast::Expr` and `ast::Stmt`.
* Some of the statement-parsing functions are refactored so that we can capture the trailing semicolon.
* `Nonterminal` and `Expr` both grew by 8 bytes, as some of the structs which are stored inline (rather than behind a `P`) now have an `Option<TokenStream>` field. Hopefully the performance impact of doing this is negligible.
BTreeMap: move up reference to map's root from NodeRef
Since the introduction of `NodeRef` years ago, it also contained a mutable reference to the owner of the root node of the tree (somewhat disguised as *const). Its intent is to be used only when the rest of the `NodeRef` is no longer needed. Moving this to where it's actually used, thought me 2 things:
- Some sort of "postponed mutable reference" is required in most places that it is/was used, and that's exactly where we also need to store a reference to the length (number of elements) of the tree, for the same reason. The length reference can be a normal reference, because the tree code does not care about tree length (just length per node).
- It's downright obfuscation in `from_sorted_iter` (transplanted to #75329)
- It's one of the reasons for the scary notice on `reborrow_mut`, the other one being addressed in #73971.
This does repeat the raw pointer code in a few places, but it could be bundled up with the length reference.
r? `@Mark-Simulacrum`
We currently only attach tokens when parsing a `:stmt` matcher for a
`macro_rules!` macro. Proc-macro attributes on statements are still
unstable, and need additional work.
add the `const_evaluatable_checked` feature
Implements a rather small subset of https://github.com/rust-lang/compiler-team/issues/340
Unlike the MCP, this does not try to compare different constant, but instead only adds the constants found in where clauses
to the predicates of a function. This PR adds the feature gate `const_evaluatable_checked`, without which nothing should change.
r? @oli-obk @eddyb
Reword `trivial_casts` lint in rustc book to better explain what it does.
The current description of the trivial casts lint under the "allowed
by default" listing in the rustc book indicates the lint is for casts
which may be removed, which is less clear than saying it's for casts
which may be replaced by coercion (which is the wording used by the
error message included in the doc).
This commit changes the wording slightly to better describe what the
lint does.
This issue bit me in some recent code where I was attempting to
convert a `Vec<SomeType>` to a `Vec<SomeTraitObject>`, and
hit my project-wide `#![deny(trivial_casts)]` with
`map(|o| Box::new(o) as TraitObject)`. I'd read the book docs for
`trivial_casts` and was surprised by the error, as I took it to mean
the cast ought to be removed (rather than replaced by ascription
in this case). Removing the cast meant other code didn't compile,
and I then found issues like #23742 and realized my misunderstanding.
Validate removal of AscribeUserType, FakeRead, and Shallow borrow
Those statements are removed by CleanupNonCodegenStatements pass
in drop lowering phase, and should not occur afterwards.
typeck: don't suggest inaccessible private fields
Fixes#76077.
This PR adjusts the missing field diagnostic logic in typeck so that when none of the missing fields in a struct expr are accessible then the error is less confusing.
r? @estebank
Add revisions to const generic issue UI tests.
Fixes#75279.
I have gotten into the flow, so I can do more of these if requested. I'm looking for feedback as to whether my work is on the right track so far.
Syntactically permit unsafety on mods
Similar to https://github.com/rust-lang/rust/pull/66183; we will accept these constructs syntactically but reject with a semantic check after macro expansion if a proc macro hasn't replaced it with something else meaningful to Rust.
```rust
#[mymacro]
unsafe mod m {
...
}
#[mymacro]
unsafe extern "C++" {
...
}
```
The intention is that this might be used as a kind of "item-level unsafe" in attribute macro DSLs -- holding things which are unsafe to declare but potentially safe to use. For example I look forward to using this in https://github.com/dtolnay/cxx.
In the absence of a procedural macro rewriting them to something else, they'll continue to be rejected at compile time though with a better error message than before.
### Before:
```console
error: expected item, found keyword `unsafe`
--> src/main.rs:1:1
|
1 | unsafe mod m {
| ^^^^^^ expected item
```
### After:
```console
error: module cannot be declared unsafe
--> src/main.rs:1:1
|
1 | unsafe mod m {
| ^^^^^^
error: extern block cannot be declared unsafe
--> src/main.rs:4:1
|
4 | unsafe extern "C++" {
| ^^^^^^
```
Closes#68048.
This commit adjusts the missing field diagnostic logic for struct
patterns in typeck to improve the diagnostic when the missing fields are
inaccessible.
Signed-off-by: David Wood <david@davidtw.co>
This commit adjusts the missing field diagnostic logic for struct
expressions in typeck to improve the diagnostic when the missing
fields are inaccessible.
Signed-off-by: David Wood <david@davidtw.co>
ci: avoid moving the build directory on GHA
While waiting for a PR job to start testing my code, I noticed the symlink-build-dir step took 10 minutes to complete, so I investigated what caused that.
It seems like something changed in the build environment between version 20200901.1 (where the step took 45 seconds) and version 20200908.1 (where the step took 10 minutes). At the time of writing this commit, the rust-lang organization is on vertsion 20200908.1, while the rust-lang-ci organization is at version 20200901.1 (and is not affected by this yet).
There is no need for this step anymore on GHA, as our XL builders got an increase in the root paritition size, so this commit removes the code that moved stuff around on GHA (while keeping it on Azure).
For the record, at the time of writing this, the disk situation is:
```
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 667G 60G 607G 9% /
/dev/sdb1 110G 4.1G 101G 4% /mnt
```
r? `@Mark-Simulacrum`
improve the suggestion of the lint `unit-arg`
Fixes#5823Fixes#6015
Changes
```
help: move the expression in front of the call...
|
3 | g();
|
help: ...and use a unit literal instead
|
3 | o.map_or((), |i| f(i))
|
```
into
```
help: move the expression in front of the call and replace it with the unit literal `()`
|
3 | g();
| o.map_or((), |i| f(i))
|
```
changelog: improve the suggestion of the lint `unit-arg`
