make &mut !Unpin not dereferenceable, and Box<!Unpin> not noalias
See https://github.com/rust-lang/unsafe-code-guidelines/issues/381 and [this LLVM discussion](https://discourse.llvm.org/t/interaction-of-noalias-and-dereferenceable/66979). The exact semantics of how `noalias` and `dereferenceable` interact are unclear, and `@comex` found a case of LLVM actually exploiting that ambiguity for optimizations. I think for now we should treat LLVM `dereferenceable` as implying a "fake read" to happen immediately at the top of the function (standing in for the spurious reads that LLVM might introduce), and that fake read is subject to all the usual `noalias` restrictions. This means we cannot put `dereferenceable` on `&mut !Unpin` references as those references can alias with other references that are being read and written inside the function (e.g. for self-referential generators), meaning the fake read introduces aliasing conflicts with those other accesses.
For `&` this is already not a problem due to https://github.com/rust-lang/rust/pull/98017 which removed the `dereferenceable` attribute for other reasons.
Regular `&mut Unpin` references are unaffected, so I hope the impact of this is going to be tiny.
The first commit does some refactoring of the `PointerKind` enum since I found the old code very confusing each time I had to touch it. It doesn't change behavior.
Fixes https://github.com/rust-lang/miri/issues/2714
EDIT: Turns out our `Box<!Unpin>` treatment was incorrect, too, so the PR also fixes that now (in codegen and Miri): we do not put `noalias` on these boxes any more.
Add nicer output to PGO build timer
This PR modifies the timer used in the PGO build script to contain nicer, hierarchical output of the individual build steps. It's not trivial to test locally, so I'll fire up a dist build right away.
r? ``@Mark-Simulacrum``
consolidate bootstrap docs
With this diff, I tried to consolidate bootstrap documentations and remove the duplicated informations.
Coupled with https://github.com/rust-lang/rustc-dev-guide/pull/1563Resolves#90686
Signed-off-by: ozkanonur <work@onurozkan.dev>
Replace nbsp in all rustdoc code blocks
Based on #106125 by `@dtolnay` — this PR fixes the line wrapping bug.
Fixes#106098. This makes code copyable from rustdoc rendered documentation into a Rust source file.
Implement epoll_wait
This PR continues working on https://github.com/rust-lang/miri/issues/602.
This is an implementation for `sleep`, though admittedly not a good one. It just does busy waiting.
Rollup of 6 pull requests
Successful merges:
- #106575 (Suggest `move` in nested closure when appropriate)
- #106805 (Suggest `{var:?}` when finding `{?:var}` in inline format strings)
- #107500 (Add tests to assert current behavior of large future sizes)
- #107598 (Fix benchmarks in library/core with black_box)
- #107602 (Parse and recover from type ascription in patterns)
- #107608 (Use triple rather than arch for fuchsia test-runner)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Use triple rather than arch for fuchsia test-runner
This allows the user of the test-runner script to specify a full triple rather than just an architecture which helps with the transition from the two component to three component target triples for fuchsia.
Enable Cargo's sparse protocol in CI
This enables the sparse protocol in CI in order to exercise and dogfood it. This is intended test the production server in a real-world situation.
Closes#107342
Add `rust.lto=off` to bootstrap and set as compiler/library default
Closes#107202
The issue mentions `embed-bitcode=on`, but here c8e6a9e8b6/src/bootstrap/compile.rs (L379-L381)
it appears that this is always set for std stage 1+, so I'm unsure if changes are needed here.
`@rustbot` label +A-bootstrap
Inline CSS background images directly into the CSS
A nice advantage of this is that it removes a few entries in the list of static files.
r? ``@notriddle``
Rollup of 6 pull requests
Successful merges:
- #107389 (Fixing confusion between mod and remainder)
- #107442 (improve panic message for slice windows and chunks)
- #107470 (Small bootstrap improvements)
- #107487 (Make the "extra if in let...else block" hint a suggestion)
- #107499 (Do not depend on Generator trait when deducing closure signature)
- #107533 (Extend `-Z print-type-sizes` to distinguish generator upvars+locals from "normal" fields.)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Small bootstrap improvements
- i/o-less check for `xz` availability
- cache result of NixOS detection
- load correct `bootstrap` module even when a package of that name is installed
- no `-W semicolon_in_expressions_from_macros` – it is warn-by-default
- one type per variable (making dynamic typing less confusing)
- integrate python-side `--help` flag into the argument parser (makes `-hv` work as a short form of `--help --verbose`)
I even checked that it works with Python 2.
Update cargo
18 commits in 3c5af6bed9a1a243a693e8e22ee2486bd5b82a6c..e84a7928d93a31f284b497c214a2ece69b4d7719 2023-01-24 15:48:15 +0000 to 2023-01-31 22:18:09 +0000
- chore: Add autolabel for `Command-*` labels (rust-lang/cargo#11664)
- Update cross test instructions for aarch64-apple-darwin (rust-lang/cargo#11663)
- Make cargo install report needed features (rust-lang/cargo#11647)
- docs(contrib): Remove out-of-date process step (rust-lang/cargo#11662)
- Do not error for `auth-required: true` without `-Z sparse-registry` (rust-lang/cargo#11661)
- Warn on commits to non-default branches. (rust-lang/cargo#11655)
- Avoid saving the same future_incompat warning multiple times (rust-lang/cargo#11648)
- Mention current default value in `publish.timeout` docs (rust-lang/cargo#11652)
- Make cargo aware of dwp files. (rust-lang/cargo#11572)
- Reduce target info rustc query calls (rust-lang/cargo#11633)
- Bump to 0.70.0; update changelog (rust-lang/cargo#11640)
- Enable sparse protocol in CI (rust-lang/cargo#11632)
- Fix split-debuginfo support detection (rust-lang/cargo#11347)
- refactor(toml): Move `TomlWorkspaceDependency` out of `TomlDependency` (rust-lang/cargo#11565)
- book: describe how the current resolver sometimes duplicates deps (rust-lang/cargo#11604)
- `cargo add` check `[dependencies]` order without considering the dotted item (rust-lang/cargo#11612)
- Link CoC to www.rust-lang.org/conduct.html (rust-lang/cargo#11622)
- Add more labels to triagebot (rust-lang/cargo#11621)
r? `@ghost`
