Use enums to clarify `DepNodeColorMap` color marking
When a function's documentation has to explain the meaning of nested results and options, then it is often a good candidate for using a custom result enum instead.
This PR also renames `DepNodeColorMap::try_mark` to `try_set_color`, to make it more distinct from the similarly-named `DepGraph::try_mark_green`.
The difference is that `try_mark_green` is a higher-level operation that tries to determine whether a node _can_ be marked green, whereas `try_set_color` is a lower-level operation that actually records a colour for the node.
The updated docs for `try_set_color` also fix a typo: *atomicaly* → *atomically*.
r? nnethercote (or compiler)
Update the tracking issue for #[diagnostic::on_move]
PR rust-lang/rust#150935 has been merged and then I have opened the tracking issue (whoops ?). So this update `compiler/rustc_feature/src/unstable.rs` to point to the right tracking issue.
This is related to the tracking issue rust-lang/rust#154181
diagnostics: avoid ICE for undeclared generic parameter in impl
Avoid an ICE for:
struct A;
impl A<B> {}
The compiler no longer panics and can proceed to emit existing diagnostics.
Adds `tests/ui/missing/undeclared-generic-parameter.rs`.
Fixesrust-lang/rust#154165 and introduced by rust-lang/rust#152913
allow `incomplete_features` in most UI tests
This PR allows the `incomplete_features` lint for all UI tests except for the three directories with the largest number of tests (`traits`, `specialization` and `const-generics`) triggering this lint to keep the size of this PR manageable. The remaining three directories will be handled in followup PRs.
Part of https://github.com/rust-lang/rust/issues/154168.
ui/lto: move and rename two tests from issues/
Move:
- `tests/ui/issues/issue-44056.rs` -> `tests/ui/lto/lto-avx-target-feature.rs`
- The first test enables both AVX target features and LTO but does not exercise AVX-specific behavior. The test primarily checks that LTO builds successfully with these flags; place it under `ui/lto` for consistency.
- `tests/ui/issues/issue-51947.rs` -> `tests/ui/lto/lto-weak-merge-functions.rs`
- The second test exercises weak linkage interacting with LTO (merge-functions), so it should belong in `ui/lto`.
I have also added a commented line at the top of each test file indicating the issue it originated from.
Skip stack_start_aligned for immediate-abort
This improves startup performance by 16%, shown by an optimized hello-world program. glibc's `pthread_getattr_np` performs expensive syscalls when reading `/proc/self/maps`. That is all wasted with `panic = immediate-abort` active because `init()` immediately discards the return value from `install_main_guard()`. A similar improvement can be seen in environments that don't have `/proc`. This change is safe because the immediately succeeding comment says that we rely on Linux's "own stack-guard mechanism".
Tracking issue: https://github.com/rust-lang/rust/issues/147286
# Benchmark
Set it up with `cargo new hello-world2`, and replace these files:
```toml
# Cargo.toml
cargo-features = ["panic-immediate-abort"]
[package]
name = "hello-world"
version = "0.1.0"
edition = "2024"
[profile.release]
lto = true
panic = "immediate-abort"
codegen-units = 1
opt-level = "z"
strip = true
# .cargo/config.toml
[unstable]
build-std = ["std"]
```
## Before
```console
home@daniel-desktop3:~/CLionProjects/hello-world2$ hyperfine -N target/release/hello-world2
Benchmark 1: target/release/hello-world2
Time (mean ± σ): 524.8 µs ± 65.1 µs [User: 276.1 µs, System: 187.0 µs]
Range (min … max): 446.4 µs … 975.5 µs 3996 runs
home@daniel-desktop3:~/CLionProjects/hello-world2$ hyperfine -N target/release/hello-world2
Benchmark 1: target/release/hello-world2
Time (mean ± σ): 519.4 µs ± 65.8 µs [User: 282.1 µs, System: 177.7 µs]
Range (min … max): 443.2 µs … 830.5 µs 3612 runs
home@daniel-desktop3:~/CLionProjects/hello-world2$ hyperfine -N target/release/hello-world2
Benchmark 1: target/release/hello-world2
Time (mean ± σ): 520.0 µs ± 64.3 µs [User: 277.1 µs, System: 182.1 µs]
Range (min … max): 447.1 µs … 1001.3 µs 3804 runs
```
For a visualization of the problem, run `cargo +stage1 build --release && perf record --call-graph dwarf -F max ./target/release/hello-world2 && perf script | inferno-collapse-perf | inferno-flamegraph > flamegraph.svg`:
<img width="3832" height="1216" alt="flamegraph with 17.41% __pthread_getattr_np" src="https://github.com/user-attachments/assets/acc2286e-1582-4772-9e3b-68b5c35e3e70" />
## After
```console
home@daniel-desktop3:~/CLionProjects/hello-world2$ hyperfine -N target/release/hello-world2Benchmark 1: target/release/hello-world2
Time (mean ± σ): 444.7 µs ± 57.3 µs [User: 257.4 µs, System: 130.2 µs]
Range (min … max): 379.4 µs … 1289.3 µs 3893 runs
Warning: Statistical outliers were detected. Consider re-running this benchmark on a quiet system without any interferences from other programs. It might help to use the '--warmup' or '--prepare' options.
home@daniel-desktop3:~/CLionProjects/hello-world2$ hyperfine -N target/release/hello-world2
Benchmark 1: target/release/hello-world2
Time (mean ± σ): 452.3 µs ± 60.7 µs [User: 261.5 µs, System: 133.5 µs]
Range (min … max): 374.9 µs … 1512.4 µs 4177 runs
Warning: Statistical outliers were detected. Consider re-running this benchmark on a quiet system without any interferences from other programs. It might help to use the '--warmup' or '--prepare' options.
home@daniel-desktop3:~/CLionProjects/hello-world2$ hyperfine -N target/release/hello-world2
Benchmark 1: target/release/hello-world2
Time (mean ± σ): 441.2 µs ± 56.1 µs [User: 256.2 µs, System: 128.8 µs]
Range (min … max): 375.0 µs … 760.4 µs 4032 runs
```
docs(fs): Clarify That File::lock Coordinates Across Processes
### Summary:
The documentation for `lock`, `lock_shared`, `try_lock`, and `try_lock_shared` did not make it clear that these are OS level file locks that coordinate access across processes, not just between handles within the current process.
Add "in this or any other process" to each method's existing description to clarify this.
Fixesrust-lang/rust#153618
r? @Mark-Simulacrum
std: move `sys::pal::os` to `sys::paths`
Part of rust-lang/rust#117276.
After rust-lang/rust#150723, rust-lang/rust#153130, rust-lang/rust#153341 and rust-lang/rust#153413, `sys::pal::os` only contains default-path related functions (like `getcwd` and the `PATH`-splitting logic). In line with rust-lang/rust#117276, this PR thus moves all these implementations into a new module in `sys`: `sys::paths`.
~There is one functional change here: The `chdir` implementation on SGX used to use `sgx_ineffective` which silently fails, but now returns an error unconditionally – I think that's much more reasonable given that SGX doesn't support filesystem stuff at all.~
I've corrected the misleading panic messages in `temp_dir` for UEFI and WASI, aside from that, this PR only consists of code moves.
CC @jethrogb @raoulstrackx @aditijannu for the SGX change (resolved)
Simplify find_attr! for HirId usage
Add a `HasAttrs<'tcx, Tcx>` trait to `rustc_hir` that allows `find_attr!` to accept `DefId`, `LocalDefId`, `OwnerId`, and `HirId` directly, instead of requiring callers to manually fetch the attribute slice first.
Before:
`find_attr!(tcx.hir_attrs(hir_id), SomeAttr)`
After:
`find_attr!(tcx, hir_id, SomeAttr)`
The trait is defined in `rustc_hir` with a generic `Tcx` parameter to avoid a dependency cycle (`rustc_hir` cannot depend on `rustc_middle`). The four concrete impls for `TyCtxt` are in `rustc_middle`.
Fixes https://github.com/rust-lang/rust/issues/153103
Move `freeze_*` methods to `OpenOptionsExt2`
Move the unstable `freeze_last_access_time` and `freeze_last_write_time` from `OpenOptionsExt` to a new `OpenOptionsExt2` trait. This should fixrust-lang/rust#153486.
Unknown -> Unsupported compression algorithm
Both zstd and zlib are *known* compression algorithms, they just may not be supported by the backend. We shouldn't mislead users into e.g. thinking they made a typo.
cc https://github.com/rust-lang/rust/issues/120953
Lifted intersperse and intersperse_with Fused transformation and updated documentation + tests
This PR once again builds on top of rust-lang/rust#152855. From the discussion in rust-lang/rust#152855, libs team came to the conclusion that `intersperse`/`intersperse_with` shouldn't transform the given iterator to a fused iterator always and a separator should be emitted between `Some(_)` items for non fused iterators (particularly just right before the subsequent `Some(_)`).
On top of the change Zakarumych added in the PR, I lifted the `FusedIterator` trait and transformation of the inner `iter` for `Intersperse`/`IntersperseWith`, so that we can display this behavior. I've adjusted the documentation and tests accordingly to reflect this change as well.
r? @jhpratt
Rename `target.abi` to `target.cfg_abi` and enum-ify llvm_abiname
See [Zulip](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/De-spaghettifying.20ABI.20controls/with/578893542) for more context. Discussed a bit in https://github.com/rust-lang/rust/pull/153769#discussion_r2934399038 too.
This renames `target.abi` to `target.cfg_abi` to make it less likely that someone will use it to determine things about the actual ccABI, i.e. the calling convention used on the target. `target.abi` does not control that calling convention, it just *sometimes* informs the user about that calling convention (and also about other aspects of the ABI).
Also turn llvm_abiname into an enum to make it more natural to match on.
Cc @workingjubilee @madsmtm
Fix environ on FreeBSD with cdylib targets that use -Wl,--no-undefined .
Instead of relying on the linker to find the 'environ' symbol, use dlsym. This fixes using `environ` from cdylibs that link with `-Wl,--no-undefined` .
Fixesrust-lang/rust#153451
Sponsored by: ConnectWise
Optimize BTreeMap::append() using CursorMut
Since [`BTreeMap::merge`](https://github.com/rust-lang/rust/pull/152418#issuecomment-3959764862) uses `CursorMut` to avoid reconstructing the map from scratch and instead inserting other `BTreeMap` at the right places or overwriting the value in self `BTreeMap` on conflict, we might as well do the same for `BTreeMap::append`. This also means that some of the code in `append.rs` can be removed; `bulk_push()` however is used by `bulk_build_from_sorted_iterator()`, which is used by the `From`/`FromIterator` trait impl on `BTreeMap`. Feels like we should rename the file or place the `bulk_push()` in an existing file.
The same additional optimization consideration that `BTreeMap::merge` has is also applied to `BTreeMap::append`.
r? @Mark-Simulacrum since Mark has seen the `BTreeMap::merge` code already (only diff is the `Ordering::Equal` case and now one of the test assertions on a panic case has the correct value now).
Both zstd and zlib are *known* compression algorithms, they just may not
be supported by the backend. We shouldn't mislead users into e.g.
thinking they made a typo.
When a function's documentation has to explain the meaning of nested results
and options, then it is often a good candidate for using a custom result enum
instead.
This commit also renames `DepNodeColorMap::try_mark` to `try_set_color`, to
make it more distinct from the similarly-named `DepGraph::try_mark_green`.
The difference is that `try_mark_green` is a higher-level operation that tries
to determine whether a node _can_ be marked green, whereas `try_set_color` is a
lower-level operation that actually records a color for the node.
Remove the `anon` query modifier
Prior experiments:
- https://github.com/rust-lang/rust/pull/152268
- https://github.com/rust-lang/rust/pull/153996
[Zulip thread: *Removing the `anon` query modifier*](https://rust-lang.zulipchat.com/#narrow/channel/582699-t-compiler.2Fquery-system/topic/Removing.20the.20.60anon.60.20query.20modifier/with/580760962)
---
There are currently three queries that use the `anon` modifier:
- `check_representability`
- `check_representability_adt_ty`
- `erase_and_anonymize_regions_ty`
It seems that none of them are using `anon` in an essential way.
According to comments and tests, the *representability* queries mainly care about not being eligible for forcing (despite having a recoverable key type), so that if a cycle does occur then the entire cycle will be on the query stack. Replacing `anon` with a new `no_force` modifier gives a modest perf improvement.
The `erase_and_anonymize_regions_ty` query appears to be using `anon` to reduce the dep-graph overhead of a query that is expected to not call any other queries (and thus have no dependencies). Replacing `anon` with either `no_hash` or nothing appears to give only a very small perf hit on `cargo` benchmarks, which is justified by the fact that it lets us remove a lot of machinery for anonymous queries.
We still need to retain some of the machinery for anonymous *tasks*, because the non-query task `DepKind::TraitSelect` still uses it.
---
I have some ideas for a follow-up that will reduce dep-graph overhead by replacing *all* zero-dependency nodes with a singleton node, but I want to keep that separate in case it causes unexpected issues and needs to be bisected or reverted.
Avoid an ICE for:
struct A;
impl A<B> {}
The compiler no longer panics and can proceed to emit existing diagnostics.
Adds `tests/ui/missing/undeclared-generic-parameter.rs`.
Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com>
binarycat