Previously, the CLI --target/--host definitions and configured options differed
in their effect: when setting these on the CLI, only the passed triples would be
compiled for, while in config.toml we would also compile for the build triple
and any host triples. This is needlessly confusing; users expect --target and
--host to be identical to editing the configuration file.
The new behavior is to respect --host and --target when passed as the *only*
configured triples (no triples are implicitly added). The default for --host is
the build triple, and the default for --target is the host triple(s), either
configured or the default build triple.
rustc is a natively cross-compiling compiler, and generally none of our steps
should care whether they are using a compiler built of triple A or B, just the
--target directive being passed to the running compiler. e.g., when building for
some target C, you don't generally want to build two stds: one with a host A
compiler and the other with a host B compiler. Just one std is sufficient.
rustbuild: Build tests with LLD if `use-lld = true` was passed
Addresses https://github.com/rust-lang/rust/pull/76127#discussion_r479932392.
Our test suite is generally ready to run with an explicitly specified linker (https://github.com/rust-lang/rust/pull/45191),
so LLD specified with `use-lld = true` works as well.
Only 4 tests fail (on `x86_64-pc-windows-msvc`):
```
ui/panic-runtime/lto-unwind.rs
run-make-fulldeps/debug-assertions
run-make-fulldeps/foreign-exceptions
run-make-fulldeps/test-harness
```
All of them are legitimate issues with LLD (or at least with combination Rust+LLD) and manifest in segfaults on access to TLS (https://github.com/rust-lang/rust/pull/76127#issuecomment-683473325). UPD: These issues are caused by https://github.com/rust-lang/rust/issues/72145 and appear because I had `-Ctarget-cpu=native` set.
UPD: Further commits build tests with LLD for non-MSVC targets and propagate LLD to more places when `use-lld` is enabled.
Add CONST_ITEM_MUTATION lint
Fixes#74053Fixes#55721
This PR adds a new lint `CONST_ITEM_MUTATION`.
Given an item `const FOO: SomeType = ..`, this lint fires on:
* Attempting to write directly to a field (`FOO.field = some_val`) or
array entry (`FOO.array_field[0] = val`)
* Taking a mutable reference to the `const` item (`&mut FOO`), including
through an autoderef `FOO.some_mut_self_method()`
The lint message explains that since each use of a constant creates a
new temporary, the original `const` item will not be modified.
Rollup of 7 pull requests
Successful merges:
- #74787 (Move `rustllvm` into `compiler/rustc_llvm`)
- #76458 (Add drain_filter method to HashMap and HashSet)
- #76472 (rustbuild: don't set PYTHON_EXECUTABLE and WITH_POLLY cmake vars since they are no longer supported by llvm)
- #76497 (Use intra-doc links in `core::ptr`)
- #76500 (Add -Zgraphviz_dark_mode and monospace font fix)
- #76543 (Document btree's unwrap_unchecked)
- #76556 (Revert #76285)
Failed merges:
r? `@ghost`
Use intra-doc links in `core::ptr`
Part of #75080.
The only link that I did not change is a link to a function on the
`pointer` primitive because intra-doc links for the `pointer` primitive
don't work yet (see #63351).
---
@rustbot modify labels: A-intra-doc-links T-doc
rustbuild: don't set PYTHON_EXECUTABLE and WITH_POLLY cmake vars since they are no longer supported by llvm
This resolves
CMake Warning:
Manually-specified variables were not used by the project:
PYTHON_EXECUTABLE
WITH_POLLY
Add drain_filter method to HashMap and HashSet
Add `HashMap::drain_filter` and `HashSet::drain_filter`, implementing part of rust-lang/rfcs#2140. These new methods are unstable. The tracking issue is #59618.
The added iterators behave the same as `BTreeMap::drain_filter` and `BTreeSet::drain_filter`, except their iteration order is arbitrary. The unit tests are adapted from `alloc::collections::btree`.
This branch rewrites `HashSet` to be a wrapper around `hashbrown::HashSet` rather than `std::collections::HashMap`.
(Both are themselves wrappers around `hashbrown::HashMap`, so the in-memory representation is the same either way.) This lets `std` re-use more iterator code from `hashbrown`. Without this change, we would need to duplicate much more code to implement `HashSet::drain_filter`.
This branch also updates the `hashbrown` crate to version 0.9.0. Aside from changes related to the `DrainFilter` iterators, this version only changes features that are not used in libstd or rustc. And it updates `indexmap` to version 1.6.0, whose only change is compatibility with `hashbrown` 0.9.0.
Move `rustllvm` into `compiler/rustc_llvm`
The `rustllvm` directory is not self-contained, it contains C++ code built by a build script of the `rustc_llvm` crate which is then linked into that crate.
So it makes sense to make `rustllvm` a part of `rustc_llvm` and move it into its directory.
I replaced `rustllvm` with more obvious `llvm-wrapper` as the subdirectory name, but something like `llvm-adapter` would work as well, other suggestions are welcome.
To make things more confusing, the Rust side of FFI functions defined in `rustllvm` can be found in `rustc_codegen_llvm` rather than in `rustc_llvm`. Perhaps they need to be moved as well, but this PR doesn't do that.
The presence of multiple LLVM-related directories in `src` (`llvm-project`, `rustllvm`, `librustc_llvm`, `librustc_codegen_llvm` and their predecessors) historically confused me and made me wonder about their purpose.
With this PR we will have LLVM itself (`llvm-project`), a FFI crate (`rustc_llvm`, kind of `llvm-sys`) and a codegen backend crate using LLVM through the FFI crate (`rustc_codegen_llvm`).
Enable GitHub Releases synchronization
This PR enables the triagebot feature to automatically populate [GitHub Releases](https://github.com/rust-lang/rust/releases) for this repository based on the changelog. See https://github.com/rust-lang/triagebot/pull/811 for the implementation of this feature on triagebot's side, and more insights on how it works.
Note: once this lands people subscribed to the ~~firehose~~ rust-lang/rust repository will probably receive a ton of notifications for all the releases being created, but this should be a one-time thing.
r? @Mark-Simulacrum
cc @rust-lang/release
Improve unresolved use error message
"use of undeclared type or module `foo`" doesn't mention that it could be a crate.
This error can happen when users forget to add a dependency to `Cargo.toml`, so I think it's important to mention that it could be a missing crate.
I've used a heuristic based on Rust's naming conventions. It complains about an unknown type if the ident starts with an upper-case letter, and crate or module otherwise. It seems to work very well. The expanded error help covers both an unknown type and a missing crate case.
Add `-Z combine_cgu` flag
Introduce a compiler option to let rustc combines all regular CGUs into a single one at the end of compilation.
Part of Issue #64191
VS code graphviz extensions use d3-graphviz, which supports `Courier`
fontname but does not support `monospace`. This caused graphs to render
poorly because the text sizes were wrong.
make `ConstEvaluatable` more strict
relevant zulip discussion: https://rust-lang.zulipchat.com/#narrow/stream/146212-t-compiler.2Fconst-eval/topic/.60ConstEvaluatable.60.20generic.20functions/near/204125452
Let's see how much this impacts. Depending on how this goes this should probably be a future compat warning.
Short explanation: we currently forbid anonymous constants which depend on generic types, e.g. `[0; std::mem::size_of::<T>]` currently errors.
We previously checked this by evaluating the constant and returned an error if that failed. This however allows things like
```rust
const fn foo<T>() -> usize {
if std::mem::size_of::<*mut T>() < 8 { // size of *mut T does not depend on T
std::mem::size_of::<T>()
} else {
8
}
}
fn test<T>() {
let _ = [0; foo::<T>()];
}
```
which is a backwards compatibility hazard. This also has worrying interactions with mir optimizations (https://github.com/rust-lang/rust/pull/74491#issuecomment-661890421) and intrinsics (#74538).
r? `@oli-obk` `@eddyb`
BTreeMap mutable iterators should not take any reference to visited nodes during iteration
Fixes#73915, overlapping mutable references during BTreeMap iteration
r? `@RalfJung`
Make rustdoc output deterministic for UI tests
Closes https://github.com/rust-lang/rust/issues/76442 (hopefully, since it's non-deterministic I don't have a way to test).
r? `@Mark-Simulacrum`
cc `@GuillaumeGomez`
rustdoc: Fix font CSS for crate lists
I had put it in the wrong file in #76126. This should fix it now. Thank
you to `@ollie27` for pointing this out!
---
`@rustbot` modify labels: T-rustdoc C-bug