Update `Arc::try_unwrap()` docs
Clarify the language wrt "race condition" not meaning "memory unsafety".
The docs make an important point about a 'logical' race condition that can occur if the `Err`-case in `Arc::try_unwrap()` is not handled properly. The language as is uses the term "race condition", which the reader may associate with "memory unsafety". This PR tries to clarify the scenario and qualify "race condition without memory unsafety".
unify git command preperation
Due to https://github.com/rust-lang/rust/issues/125954, we had to modify git invocations with certain flags in https://github.com/rust-lang/rust/pull/126255. However, because there are so many instances of `Command::new("git")` in bootstrap, it is difficult to apply these solutions to all of them.
This PR creates a helper function that unifies the git usage in bootstrap. Meaning, whenever special flags or hacks are needed, we can apply them to this single function which makes things much simpler for the bootstrap team.
Spell out other trait diagnostic
I recently saw somebody confused about the diagnostic thinking it was suggesting to add an `as` cast. This change is longer but I think it's clearer
Document behavior of `create_dir_all` wrt. empty path
The behavior makes sense because `Path::new("one_component").parent() == Some(Path::new(""))`, so if one naively wants to create the parent directory for a file to be written, it simply works.
Closes#105108 by documenting the current behavior.
Remove superfluous UbChecks from `SliceIndex` methods
The current implementation calls the unsafe ones from the safe ones, but that means they end up emitting UbChecks that are impossible to hit, since we just checked those things.
This PR adds some new module-local helpers for the code shared between them, so the safe methods can be small enough to inline by avoiding those extra checks, while the unsafe methods still help catch length mistakes.
r? `@saethlin`
Disable `llvm-bitcode-linker` in the default bootstrap profiles
I don't think that we really need to enable `llvm-bitcode-linker` in the default bootstrap profiles, since it seems that it is only useful for running `nvptx` tests. It should be enabled on CI, which it is, and that should be enough. People can enable it easily locally, if they want.
The linker causes occasionally some rebuild issues (https://github.com/rust-lang/rust/issues/122491, https://github.com/rust-lang/rust/issues/126464), but more importantly it is just needless work to build it locally.
I kept it enabled for `dist`, because it is distributed as a `rustup` component (for some reason it's not included in `extended`? not sure).
Fixes: https://github.com/rust-lang/rust/issues/126464
ci: Update centos:7 to use vault repos
CentOS 7 is going EOL on June 30, after which its package repos will no
longer exist on the regular mirrors. We'll still be able to access
packages from the vault server though, and can start doing so now. This
affects `dist-i686-linux` and `dist-x86_64-linux`.
I also removed `epel-release` because we were only using that for its
`cmake3`, but we've been building our own version for a while.
try-job: dist-i686-linux
try-job: dist-x86_64-linux
Rollup of 9 pull requests
Successful merges:
- #126229 (Bump windows-bindgen to 0.57)
- #126404 (Check that alias-relate terms are WF if reporting an error in alias-relate)
- #126410 (smir: merge identical Constant and ConstOperand types)
- #126478 (Migrate `run-make/codegen-options-parsing` to `rmake.rs`)
- #126496 (Make proof tree probing and `Candidate`/`CandidateSource` generic over interner)
- #126508 (Make uninitialized_error_reported a set of locals)
- #126517 (Migrate `run-make/dep-graph` to `rmake.rs`)
- #126525 (trait_selection: remove extra words)
- #126526 (tests/ui/lint: Move 19 tests to new `non-snake-case` subdir)
r? `@ghost`
`@rustbot` modify labels: rollup
tests/ui/lint: Move 19 tests to new `non-snake-case` subdir
Mainly so that it is easier to only run all `non_snake_case`-lint-specific tests with:
./x test tests/ui/lint/non-snake-case
But also to reduce the size of the large `tests/ui/lint` directory. And rename some tests to pass tidy, and remove them from `src/tools/tidy/src/issues.txt`.
Make uninitialized_error_reported a set of locals
Another artifact of how places used to be able to be based on statics and not just locals. This set is exclusively filled with PlaceRefs that are just locals, so it should just contain locals directly.
Make proof tree probing and `Candidate`/`CandidateSource` generic over interner
`<TyCtxt<'tcx>>` is ugly, but will become `<I>` when things actually become generic.
r? lcnr
smir: merge identical Constant and ConstOperand types
The first commit renames the const operand visitor functions on regular MIR to match the type name, that was forgotten in the original rename.
The second commit changes stable MIR, fixing https://github.com/rust-lang/project-stable-mir/issues/71. Previously there were two different smir types for the MIR type `ConstOperand`, one used in `Operand` and one in `VarDebugInfoContents`.
Maybe we should have done this with https://github.com/rust-lang/rust/pull/125967, so there's only a single breaking change... but I saw that PR too late.
Fixes https://github.com/rust-lang/project-stable-mir/issues/71
Check that alias-relate terms are WF if reporting an error in alias-relate
Check that each of the left/right term is WF when deriving a best error obligation for an alias-relate goal. This will make sure that given `<i32 as NotImplemented>::Assoc = ()` will drill down into `i32: NotImplemented` since we currently treat the projection as rigid.
r? lcnr
Bump windows-bindgen to 0.57
This PR updates our generated Windows API bindings using the latest version of `windows-bindgen`.
The only change to the generated code is that `derive` is used for `Copy` and `Clone` instead of `impl`.
Mainly so that it is easier to only run all `non-snake-case`-specific
tests but no other tests with:
./x test tests/ui/lint/non-snake-case
But also to reduce the size of the large `tests/ui/lint` directory. And
rename some tests to pass tidy, and remove them from
`src/tools/tidy/src/issues.txt`.
Rollup of 9 pull requests
Successful merges:
- #125829 (rustc_span: Add conveniences for working with span formats)
- #126361 (Unify intrinsics body handling in StableMIR)
- #126417 (Add `f16` and `f128` inline ASM support for `x86` and `x86-64`)
- #126424 ( Also sort `crt-static` in `--print target-features` output)
- #126428 (Polish `std::path::absolute` documentation.)
- #126429 (Add `f16` and `f128` const eval for binary and unary operationations)
- #126448 (End support for Python 3.8 in tidy)
- #126488 (Use `std::path::absolute` in bootstrap)
- #126511 (.mailmap: Associate both my work and my private email with me)
r? `@ghost`
`@rustbot` modify labels: rollup
Add `f16` and `f128` const eval for binary and unary operationations
Add const evaluation and Miri support for f16 and f128, including unary and binary operations. Casts are not yet included.
Fixes https://github.com/rust-lang/rust/issues/124583
r? ``@RalfJung``
Polish `std::path::absolute` documentation.
These changes bring it closer to other standard library documentation and, in particular, `std::fs::canonicalize`, which it will often be compared with.
* Add `# Platform-specific behavior` section, with content moved from Examples section.
* Create `# Errors` section.
* Phrase error description to allow future platforms to have new syntactic errors, rather than only emptiness.
* Add missing commas.
* Indent example code 4 spaces.
Also sort `crt-static` in `--print target-features` output
I didn't find `crt-static` at first (for `x86_64-unknown-linux-gnu`), because it was put at the bottom of the large and otherwise sorted list.
Fully sort the list before we print it.
Note that `llvm_target_features` starts out and remains sorted and does not need to be sorted an extra time.
On my machine the diff is just:
```diff
$ diff -u /tmp/before2.txt /tmp/after2.txt
--- /tmp/before2.txt 2024-06-13 20:40:27.091636592 +0200
+++ /tmp/after2.txt 2024-06-13 20:39:54.584894891 +0200
``@@`` -20,6 +20,7 ``@@``
bmi1 - Support BMI instructions.
bmi2 - Support BMI2 instructions.
cmpxchg16b - 64-bit with cmpxchg16b (this is true for most x86-64 chips, but not the first AMD chips).
+ crt-static - Enables C Run-time Libraries to be statically linked.
ermsb - REP MOVS/STOS are fast.
f16c - Support 16-bit floating point conversion instructions.
fma - Enable three-operand fused multiple-add.
``@@`` -49,7 +50,6 ``@@``
xsavec - Support xsavec instructions.
xsaveopt - Support xsaveopt instructions.
xsaves - Support xsaves instructions.
- crt-static - Enables C Run-time Libraries to be statically linked.
Code-generation features supported by LLVM for this target:
16bit-mode - 16-bit mode (i8086).
```
I couldn't find a ui test that tested this output. Let's see if CI finds a regression tests.
Add `f16` and `f128` inline ASM support for `x86` and `x86-64`
This PR adds `f16` and `f128` input and output support to inline ASM on `x86` and `x86-64`. `f16` vector sizes are taken from [here](https://www.intel.com/content/www/us/en/docs/intrinsics-guide/index.html).
Relevant issue: #125398
Tracking issue: #116909
``@rustbot`` label +F-f16_and_f128
Unify intrinsics body handling in StableMIR
rust-lang/rust#120675 introduced a new mechanism to declare intrinsics which will potentially replace the rust-intrinsic ABI.
The new mechanism introduces a placeholder body and mark the intrinsic with `#[rustc_intrinsic_must_be_overridden]`.
In practice, this means that a backend should not generate code for the placeholder, and shim the intrinsic.
The new annotation is an internal compiler implementation, and it doesn't need to be exposed to StableMIR users.
In this PR, we unify the interface for intrinsics marked with `rustc_intrinsic_must_be_overridden` and intrinsics that do not have a body.
Fixes https://github.com/rust-lang/project-stable-mir/issues/79
r? ``@oli-obk``
cc: ``@momvart``
Rollup of 9 pull requests
Successful merges:
- #126354 (Use `Variance` glob imported variants everywhere)
- #126367 (Point out failing never obligation for `DEPENDENCY_ON_UNIT_NEVER_TYPE_FALLBACK`)
- #126469 (MIR Shl/Shr: the offset can be computed with rem_euclid)
- #126471 (Use a consistent way to filter out bounds instead of splitting it into three places)
- #126472 (build `libcxx-version` only when it doesn't exist)
- #126497 (delegation: Fix hygiene for `self`)
- #126501 (make bors ignore comments in PR template)
- #126509 (std: suggest OnceLock over Once)
- #126512 (Miri subtree update)
r? `@ghost`
`@rustbot` modify labels: rollup
std: suggest OnceLock over Once
It was noted in https://github.com/rust-lang/rust/issues/125615#issuecomment-2149590818 that Once is not necessary in most cases and should be discouraged. Once is really just an implementation detail of OnceLock that others can use if they want. Suggest they use OnceLock instead.
delegation: Fix hygiene for `self`
And fix diagnostics for `self` from a macro.
The missing rib caused `self` to be treated as a generic parameter and ignore `macro_rules` hygiene.
Addresses this comment https://github.com/rust-lang/rust/pull/124135#discussion_r1637492234.
build `libcxx-version` only when it doesn't exist
In https://github.com/rust-lang/rust/issues/126423, it seems like c++ parsing takes quite amount of time on bootstrap startups. This PR makes libcxx-version to be compiled only when it doesn't exist.
A simple demonstration on the overhead of buiding `libcxx-version`:
```sh
$ rm -rf build/host/libcxx-version
$ x build
Building bootstrap
Finished `dev` profile [unoptimized] target(s) in 0.07s
----- LIBCXX VERSION CHECK TOOK: 509ms
Building tool rustdoc (stage1 -> stage2, x86_64-unknown-linux-gnu)
Finished `release` profile [optimized] target(s) in 0.25s
Build completed successfully in 0:00:02
$ x build
Building bootstrap
Finished `dev` profile [unoptimized] target(s) in 0.07s
----- LIBCXX VERSION CHECK TOOK: 2ms
Creating a sysroot for stage2 compiler (use `rustup toolchain link 'name' build/host/stage2`)
Building tool rustdoc (stage1 -> stage2, x86_64-unknown-linux-gnu)
Finished `release` profile [optimized] target(s) in 0.14s
Build completed successfully in 0:00:01
```
Use a consistent way to filter out bounds instead of splitting it into three places
just a small cleanup, no logic change.
Initially the code had me looking for why anything was special here, only to realize there's nothing interesting going on
Point out failing never obligation for `DEPENDENCY_ON_UNIT_NEVER_TYPE_FALLBACK`
Based on top of #125289, so just need to look at the last commit.
r? `@WaffleLapkin`
Use `Variance` glob imported variants everywhere
Fully commit to using the globbed variance. Could be convinced the other way, and change this PR to not use the globbed variants anywhere, but I'd rather we do one or the other.
r? lcnr
cargo miri: add support for '--many-seeds'
to run the program / tests many times with different seeds: `cargo miri run --many-seeds` / `cargo miri test --many-seeds`.
`@rust-lang/miri` any opinion on the flag name here? Should it be `-Zmiri-many-seeds` or is `--many-seeds` fine?
Fixes https://github.com/rust-lang/miri/issues/3546
Add `TyCtxt::is_lang_item`, use it in the compiler
```rust
pub fn is_lang_item(self, def_id: DefId, lang_item: LangItem) -> bool;
```
Easier than having to use `Some(def_id) == tcx.lang_items().iterator_trait()` or something. Also makes it easier to turn into `TraitSolverLangItem` in the future. Hope it's not too bad for perf.
r? `@lcnr` or `@oli-obk`
