Add new simpler and more explicit syntax for check-cfg
<details>
<summary>
Old proposition (before the MCP)
</summary>
This PR adds a new simpler and more explicit syntax for check-cfg. It consist of two new form:
- `exhaustive(names, values)`
- `configure(name, "value1", "value2", ... "valueN")`
The preview forms `names(...)` and `values(...)` have implicit meaning that are not strait-forward. In particular `values(foo)`&`values(bar)` and `names(foo, bar)` are not equivalent which has created [some confusions](https://github.com/rust-lang/rust/pull/98080).
Also the `names()` and `values()` form are not clear either and again created some confusions where peoples believed that `values()`&`values(foo)` could be reduced to just `values(foo)`.
To fix that the two new forms are made to be explicit and simpler. See the table of correspondence:
- `names()` -> `exhaustive(names)`
- `values()` -> `exhaustive(values)`
- `names(foo)` -> `exhaustive(names)`&`configure(foo)`
- `values(foo)` -> `configure(foo)`
- `values(feat, "foo", "bar")` -> `configure(feat, "foo", "bar")`
- `values(foo)`&`values(bar)` -> `configure(foo, bar)`
- `names()`&`values()`&`values(my_cfg)` -> `exhaustive(names, values)`&`configure(my_cfg)`
Another benefits of the new syntax is that it allow for further options (like conditional checking for --cfg, currently always on) without syntax change.
The two previous forms are deprecated and will be removed once cargo and beta rustc have the necessary support.
</details>
This PR is the first part of the implementation of [MCP636 - Simplify and improve explicitness of the check-cfg syntax](https://github.com/rust-lang/compiler-team/issues/636).
## New `cfg` form
It introduces the new [`cfg` form](https://github.com/rust-lang/compiler-team/issues/636) and deprecate the other two:
```
rustc --check-cfg 'cfg(name1, ..., nameN, values("value1", "value2", ... "valueN"))'
```
## Default built-in names and values
It also changes the default for the built-in names and values checking.
- Built-in values checking would always be activated as long as a `--check-cfg` argument is present
- Built-in names checking would always be activated as long as a `--check-cfg` argument is present **unless** if any `cfg(any())` arg is passed
~~**Note: depends on https://github.com/rust-lang/rust/pull/111068 but is reviewable (last two commits)!**~~
Resolve https://github.com/rust-lang/compiler-team/issues/636
r? `@petrochenkov`
Updated libc and doc for Vita target
Doc changes:
- Updated Vita target readme. The recommended approach to build artifacts for the platform now is [cargo-vita](https://crates.io/crates/cargo-vita) which wraps all the convoluted steps previously described in a yaml for `cargo-make`
- Updated maintainer list for Vita target. (`@ZetaNumbers` `@pheki` please agree to be added to the list, `@amg98` please let us know if you're still planning on actively maintaining target support)
Code changes:
- ~Updated libc for rust-lang/libc#3284 and rust-lang/libc#3366~ (Already merged in #116527)
- In dupfd changed the flag same as for esp target, there is no CLOEXEC on Vita
- Enabled `new_pair` since we've implemented `socketpair` in Vita newlib
Implement sys::args for UEFI
- Uses `EFI_LOADED_IMAGE_PROTOCOL`, which is implemented for all loaded images.
Tested on qemu with OVMF
cc ``@nicholasbishop``
cc ``@dvdhrm``
rustdoc: hide `#[repr(transparent)]` if it isn't part of the public ABI
Fixes#90435.
This hides `#[repr(transparent)]` when the non-1-ZST field the struct is "transparent" over is private.
CC `@RalfJung`
Tentatively nominating it for the release notes, feel free to remove the nomination.
`@rustbot` label needs-fcp relnotes A-rustdoc-ui
This add a new form and deprecated the other ones:
- cfg(name1, ..., nameN, values("value1", "value2", ... "valueN"))
- cfg(name1, ..., nameN) or cfg(name1, ..., nameN, values())
- cfg(any())
It also changes the default exhaustiveness to be enable-by-default in
the presence of any --check-cfg arguments.
Fix mips platform support entries.
The table entries for these MIPS entries were broken because they had the wrong number of columns (from #116503). Additionally, there was a conflict with #115238, which made the same change (but on different lines, so git didn't complain).
Document `diagnostic_namespace` feature
This adds it to the rust unstable book.
FWIW: I couldn't find a way to serve the book locally (please send help), so I can't check that this renders correctly.
cc `@weiznich`
Update docs for mips target tier demotion.
These mips targets were demoted in #113274, but the documentation was not updated. I have also elected to document this in the release notes for 1.72 because I think that should have been included.
Also be more pedantic about spelling:
- LE? Is it "less than or equal to"? Say "little endian".
- We're Rust, not C, preserve the initial capital in "N64".
- "MUSL" doesn't stand for anything; Rich Felker spells it "musl".
In the process, be more pedantic about spelling:
- LE? Do you mean "limited edition"? It's "little endian".
- The name of the ABI is "N64" as in "Nintendo 64".
Updates documentation for LLVM CFI support with recommended information
since the user can now rebuild and use both core and std with CFI
enabled using the Cargo build-std feature.
add notes about non-compliant FP behavior on 32bit x86 targets
Based on ton of prior discussion (see all the issues linked from https://github.com/rust-lang/unsafe-code-guidelines/issues/237), the consensus seems to be that these targets are simply cursed and we cannot implement the desired semantics for them. I hope I properly understood what exactly the extent of the curse is here, let's make sure people with more in-depth FP knowledge take a close look!
In particular for the tier 3 targets I have no clue which target is affected by which particular variant of the x86_32 FP curse. I assumed that `i686` meant SSE is used so the "floating point return value" is the only problem, while everything lower (`i586`, `i386`) meant x87 is used.
I opened https://github.com/rust-lang/rust/issues/114479 to concisely describe and track the issue.
Cc `@workingjubilee` `@thomcc` `@chorman0773` `@rust-lang/opsem`
Fixes https://github.com/rust-lang/rust/issues/73288
Fixes https://github.com/rust-lang/rust/issues/72327
bootstrap major change detection implementation
The use of `changelog-seen` and `bootstrap/CHANGELOG.md` has not been functional in any way for many years. We often do major/breaking changes but never update the changelog file or the `changelog-seen`. This is an alternative method for tracking major or breaking changes and informing developers when such changes occur.
Example output when bootstrap detects a major change:

Stdio support for UEFI
- Uses Simple Text Output Protocol and Simple Text Input Protocol
- Reading is done one character at a time
- Writing is done with max 4096 characters
# Quirks
## Output Newline
- UEFI uses CRLF for newline. So when running the application in UEFI shell (qemu VGA), the output of `println` looks weird.
- However, since the UEFI shell supports piping output, I am unsure if doing any output post-processing is a good idea. UEFI shell `cat` command seems to work fine with just LF.
## Input Newline
- `Stdin.read_line()` method is broken in UEFI shell. Pressing enter seems to be read as CR, which means LF is never encountered.
- Works fine with input redirection from file.
CC `@dvdhrm`
Amend style guide section for formatting where clauses in type aliases
This PR has two parts:
1. Amend wording about breaking before or after the `=`, which is a style guide bugfix to align it with current rustfmt behavior.
2. Explain how to format trailing (#89122) where clauses, which are preferred in both GATs (#90076) and type aliases (#114662).
r? `@joshtriplett`
Update books
## rust-embedded/book
1 commits in 99ad2847b865e96d8ae7b333d3ee96963557e621..eac173690b8cc99094e1d88bd49dd61127fbd285
2023-09-12 07:34:44 UTC to 2023-09-12 07:34:44 UTC
- USB connector-type correction (rust-embedded/book#360)
## rust-lang/nomicon
1 commits in e3f3af69dce71cd37a785bccb7e58449197d940c..ddfa4214487686e91b21aa29afb972c08a8f0d5b
2023-09-22 17:04:10 UTC to 2023-09-22 17:04:10 UTC
- Fill "Beneath `std`" (rust-lang/nomicon#413)
## rust-lang/reference
1 commits in ee7c676fd6e287459cb407337652412c990686c0..5262e1c3b43a2c489df8f6717683a44c7a2260fd
2023-09-18 18:28:31 UTC to 2023-09-18 18:28:31 UTC
- we reserve the right to reduce our amount of UB (rust-lang/reference#1397)
## rust-lang/rustc-dev-guide
8 commits in 08bb147d51e815b96e8db7ba4cf870f201c11ff8..a13b7c28ed705891c681ce5417b3d1cdb12cecd1
2023-09-25 05:14:41 UTC to 2023-09-11 21:29:18 UTC
- Clarify all the `{AP,RP}IT{,IT}` impl trait types (rust-lang/rustc-dev-guide#1798)
- Modify build instructions for optimized build (rust-lang/rustc-dev-guide#1795)
- Remove outdated references to coverage debug code (rust-lang/rustc-dev-guide#1797)
- Add deep dive document about early/late bound parameters interacting with turbofish (rust-lang/rustc-dev-guide#1794)
- explain the MIR const vs TY const situation (rust-lang/rustc-dev-guide#1793)
- fix type name (rust-lang/rustc-dev-guide#1792)
- Clarify that `run-coverage` only runs in some of the CI jobs (rust-lang/rustc-dev-guide#1791)
- Document the `coverage-map` and `run-coverage` test suites (rust-lang/rustc-dev-guide#1790)
Add Minimal Std implementation for UEFI
# Implemented modules:
1. alloc
2. os_str
3. env
4. math
# Related Links
Tracking Issue: https://github.com/rust-lang/rust/issues/100499
API Change Proposal: https://github.com/rust-lang/libs-team/issues/87
# Additional Information
This was originally part of https://github.com/rust-lang/rust/pull/100316. Since that PR was becoming too unwieldy and cluttered, and with suggestion from `@dvdhrm,` I have extracted a minimal std implementation to this PR.
The example in `src/doc/rustc/src/platform-support/unknown-uefi.md` has been tested for `x86_64-unknown-uefi` and `i686-unknown-uefi` in OVMF. It would be great if someone more familiar with AARCH64 can help with testing for that target.
Signed-off-by: Ayush Singh <ayushsingh1325@gmail.com>
Raise minimum supported Apple OS versions
This implements the proposal to raise the minimum supported Apple OS versions as laid out in the now-completed MCP (https://github.com/rust-lang/compiler-team/issues/556).
As of this PR, rustc and the stdlib now support these versions as the baseline:
- macOS: 10.12 Sierra
- iOS: 10
- tvOS: 10
- watchOS: 5 (Unchanged)
In addition to everything this breaks indirectly, these changes also erase the `armv7-apple-ios` target (currently tier 3) because the oldest supported iOS device now uses ARMv7s. Not sure what the policy around tier3 target removal is but shimming it is not an option due to the linker refusing.
[Per comment](https://github.com/rust-lang/compiler-team/issues/556#issuecomment-1297175073), this requires a FCP to merge. cc `@wesleywiser.`