Stabilize C string literals
RFC: https://rust-lang.github.io/rfcs/3348-c-str-literal.html
Tracking issue: https://github.com/rust-lang/rust/issues/105723
Documentation PR (reference manual): https://github.com/rust-lang/reference/pull/1423
# Stabilization report
Stabilizes C string and raw C string literals (`c"..."` and `cr#"..."#`), which are expressions of type [`&CStr`](https://doc.rust-lang.org/stable/core/ffi/struct.CStr.html). Both new literals require Rust edition 2021 or later.
```rust
const HELLO: &core::ffi::CStr = c"Hello, world!";
```
C strings may contain any byte other than `NUL` (`b'\x00'`), and their in-memory representation is guaranteed to end with `NUL`.
## Implementation
Originally implemented by PR https://github.com/rust-lang/rust/pull/108801, which was reverted due to unintentional changes to lexer behavior in Rust editions < 2021.
The current implementation landed in PR https://github.com/rust-lang/rust/pull/113476, which restricts C string literals to Rust edition >= 2021.
## Resolutions to open questions from the RFC
* Adding C character literals (`c'.'`) of type `c_char` is not part of this feature.
* Support for `c"..."` literals does not prevent `c'.'` literals from being added in the future.
* C string literals should not be blocked on making `&CStr` a thin pointer.
* It's possible to declare constant expressions of type `&'static CStr` in stable Rust (as of v1.59), so C string literals are not adding additional coupling on the internal representation of `CStr`.
* The unstable `concat_bytes!` macro should not accept `c"..."` literals.
* C strings have two equally valid `&[u8]` representations (with or without terminal `NUL`), so allowing them to be used in `concat_bytes!` would be ambiguous.
* Adding a type to represent C strings containing valid UTF-8 is not part of this feature.
* Support for a hypothetical `&Utf8CStr` may be explored in the future, should such a type be added to Rust.
Add thinlto support to codegen, assembly and coverage tests
Using `--emit=llvm-ir` with thinlto usually result in multiple IR files.
Resolve test case failure issue reported in #113923.
miri: add test checking that aggregate assignments reset memory to uninit
Also, `write_aggregate` is really just a helper for evaluating `Aggregate` rvalues, so it should be in `step.rs`, not `place.rs`. Also factor out `Repeat` rvalues into their own function while we are at it.
r? `@saethlin`
Fixes https://github.com/rust-lang/miri/issues/3195
utilize stdlib debug assertion status in compiletest
Implemented a new flag `--with-debug-assertions` on compiletest to pass the stdlib debug assertion status from bootstrap.
Resolves#115171
Add `never_patterns` feature gate
This PR adds the feature gate and most basic parsing for the experimental `never_patterns` feature. See the tracking issue (https://github.com/rust-lang/rust/issues/118155) for details on the experiment.
`@scottmcm` has agreed to be my lang-team liaison for this experiment.
Update cargo
7 commits in 9b13310ca596020a737aaa47daa4ed9ff8898a2f..26333c732095d207aa05932ce863d850fb309386
2023-11-24 16:20:51 +0000 to 2023-11-28 20:07:39 +0000
- docs: link to the packages lint table from the related workspace table (rust-lang/cargo#13057)
- Add more doc comments for gc changes. (rust-lang/cargo#13055)
- docs: Provide pointers for MSRV (rust-lang/cargo#13056)
- Fixed typo in SemVer Compatibility documentation page (rust-lang/cargo#13054)
- refactor: use custom error instead of anyhow (rust-lang/cargo#13050)
- review and remove ignored tests in rustfix (rust-lang/cargo#13047)
- docs: add doc comments for rustfix (rust-lang/cargo#13048)
r? ghost
Remove HIR opkinds
`hir::BinOp`, `hir::BinOpKind`, and `hir::UnOp` are identical to `ast::BinOp`, `ast::BinOpKind`, and `ast::UnOp`, respectively. This seems silly, so this PR removes the HIR ones. (A re-export lets the AST ones be referred to using a `hir::` qualifier, which avoids renaming churn.)
r? `@cjgillot`
- Rename them both `as_str`, which is the typical name for a function
that returns a `&str`. (`to_string` is appropriate for functions
returning `String` or maybe `Cow<'a, str>`.)
- Change `UnOp::as_str` from an associated function (weird!) to a
method.
- Avoid needless `self` dereferences.
Update cargo
7 commits in 71cd3a926f0cf41eeaf9f2a7f2194b2aff85b0f6..9b13310ca596020a737aaa47daa4ed9ff8898a2f
2023-11-20 15:30:57 +0000 to 2023-11-24 16:20:51 +0000
- feat: Add `CARGO_RUSTC_CURRENT_DIR` (unstable) (rust-lang/cargo#12996)
- Exited with hard error when custom build file no existence or not in package (rust-lang/cargo#12995)
- try running on windows (rust-lang/cargo#13042)
- refactor(toml): Better abstract inheritance details (rust-lang/cargo#13021)
- cargo-test-support: Add features to the default Cargo.toml file (rust-lang/cargo#12997)
- Migrate rustfix to the cargo repo (rust-lang/cargo#13005)
- typo: rusc -> rustc (rust-lang/cargo#13019)
---
This also removes the check to ensure that `rustfix` between
* src/tools/cargo
* src/tools/compiletest
has the same version,
since `rust-lang/rustfix` has migrated to under `rust-lang/cargo`.
r? ghost
run the provenance-gc=1 test on all targets, but only for the host tests
No need to slow down *all those tests* running on the Linux host... but lets cover each major OS at least once. We've had bugs that only some macOS-specific code in `getrandom` found, after all.
Let's see how much this affects timing on the macOS / Windows runners.
before: only on Linux host, all tests
after: only the test suite itself (not cargo-miri or the mir-opt-level=4 run),
on all hosts for the host target and on Linux for all "full" targets.
Replace `option.map(cond) == Some(true)` with `option.is_some_and(cond)`
Requested by `@fmease` in https://github.com/rust-lang/rust/pull/118226#pullrequestreview-1747432292.
There is also a much larger number of `option.map_or(false, cond)` that can be changed separately if someone wants.
r? fmease
This removes the check to ensure that `rustfix` between
* src/tools/cargo
* src/tools/compiletest
has the same version,
since `rust-lang/rustfix` has migrated to under `rust-lang/cargo`.
Fixes error count display is different when there's only one error left
Supersedes #114759
### What did I do?
I did the small change in `rustc_errors` by hand. Then I did the other changes in `/compiler` by hand, those were just find replace on `*.rs` in the workspace. The changes in run-make are find replace for `run-make` in the workspace.
All other changes are blessed using `x test TEST --bless`. I blessed the tests that were blessed in #114759.
### how to review this nightmare
ping bors with an `r+`. You should check that my logic is sound and maybe quickly scroll through the diff, but fully verifying it seems fairly hard to impossible. I did my best to do this correctly.
Thank you `@adrianEffe` for bringing this up and your initial implementation.
cc `@flip1995,` you said you want to do a subtree sync asap
cc `@RalfJung` maybe you want to do a quick subtree sync afterwards as well for Miri
r? `@WaffleLapkin`
