modularize the config module bootstrap
Currently, our `config` module is quite large over 3,000 lines, and handles a wide range of responsibilities. This PR aims to break it down into smaller, more focused submodules to improve readability and maintainability:
* **`toml`**: Introduces a dedicated `toml` submodule within the `config` module. Its sole purpose is to define configuration-related structs along with their corresponding deserialization logic. It also contains the `parse_inner` method, which serves as the central function for extracting relevant information from the TOML structs and constructing the final configuration.
* **`rust`, `dist`, `install`, `llvm`, `build`, `gcc`, and others**: Each of these modules contains TOML subsections specific to their domain, along with the logic necessary to convert them into parts of the final configuration struct.
* **`config/mod.rs`**: Contains shared types and enums used across multiple TOML subsections.
* **`config/config.rs`**: Houses the logic that integrates all the TOML subsections into the complete configuration struct.
r? `@kobzol`
Add a new `mismatched-lifetime-syntaxes` lint
The lang-team [discussed this](https://hackmd.io/nf4ZUYd7Rp6rq-1svJZSaQ) and I attempted to [summarize](https://github.com/rust-lang/rust/pull/120808#issuecomment-2701863833) their decision. The summary-of-the-summary is:
- Using two different kinds of syntax for elided lifetimes is confusing. In rare cases, it may even [lead to unsound code](https://github.com/rust-lang/rust/issues/48686)! Some examples:
```rust
// Lint will warn about these
fn(v: ContainsLifetime) -> ContainsLifetime<'_>;
fn(&'static u8) -> &u8;
```
- Matching up references with no lifetime syntax, references with anonymous lifetime syntax, and paths with anonymous lifetime syntax is an exception to the simplest possible rule:
```rust
// Lint will not warn about these
fn(&u8) -> &'_ u8;
fn(&'_ u8) -> &u8;
fn(&u8) -> ContainsLifetime<'_>;
```
- Having a lint for consistent syntax of elided lifetimes will make the [future goal](https://github.com/rust-lang/rust/issues/91639) of warning-by-default for paths participating in elision much simpler.
---
This new lint attempts to accomplish the goal of enforcing consistent syntax. In the process, it supersedes and replaces the existing `elided-named-lifetimes` lint, which means it starts out life as warn-by-default.
jsondocck: Refactor directive handling
Best reviewed commit by commit.
1. Moves directive handling into its own file. This makes it easier to link to in the dev-guide (https://github.com/rust-lang/rustc-dev-guide/pull/2422#discussion_r2112724234), but also makes the code nicer in it's own right
2. Renames command to directive. This is what compiletest uses, and it's nice to not have 2 words for this.
r? ``@GuillaumeGomez``
`tests/ui`: A New Order [3/N]
Some `tests/ui/` housekeeping, to trim down number of tests directly under `tests/ui/`. Part of rust-lang/rust#133895.
r? ``@jieyouxu``
UnsafePinned: also include the effects of UnsafeCell
This tackles https://github.com/rust-lang/rust/issues/137750 by including an `UnsafeCell` in `UnsafePinned`, thus imbuing it with all the usual properties of interior mutability (no `noalias` nor `dereferenceable` on shared refs, special treatment by Miri's aliasing model). The soundness issue is not fixed yet because coroutine lowering does not use `UnsafePinned`.
The RFC said that `UnsafePinned` would not permit mutability on shared references, but since then, https://github.com/rust-lang/rust/issues/137750 has demonstrated that this is not tenable. In the face of those examples, I propose that we do the "obvious" thing and permit shared mutable state inside `UnsafePinned`. This seems loosely consistent with the fact that we allow going from `Pin<&mut T>` to `&T` (where the former can be aliased with other pointers that perform mutation, and hence the same goes for the latter) -- but the `as_ref` example shows that we in fact would need to add this `UnsafeCell` even if we didn't have a safe conversion to `&T`, since for the compiler and Miri, `&T` and `Pin<&T>` are basically the same type.
To make this possible, I had to remove the `Copy` and `Clone` impls for `UnsafePinned`.
Tracking issue: https://github.com/rust-lang/rust/issues/125735
Cc ``@rust-lang/lang`` ``@rust-lang/opsem`` ``@Sky9x``
I don't think this needs FCP since the type is still unstable -- we'll finally decide whether we like this approach when `UnsafePinned` is moved towards stabilization (IOW, this PR is reversible). However, I'd still like to make sure that the lang team is okay with the direction I am proposing here.
Move placeholder handling to a proper preprocessing step
This commit breaks out the logic of placheolder rewriting into its own preprocessing step. It's one of the more boring
parts of #130227.
The only functional change from this is that the preprocessing step (where extra `r: 'static` constraints are added) is performed upstream of Polonius legacy, finally affecting Polonius. That is mostly a by-product, though.
This should be reviewable by anyone in the compiler team, so
r? rust-lang/compiler
Merge `compiler-builtins` as a Josh subtree
Use the Josh [1] utility to add `compiler-builtins` as a subtree, which
will allow us to stop using crates.io for updates. This is intended to
help resolve some problems when unstable features change and require
code changes in `compiler-builtins`, which sometimes gets trapped in a
bootstrap cycle.
This was done using `josh-filter` built from the r24.10.04 tag:
git fetch https://github.com/rust-lang/compiler-builtins.git 233434412fe7eced8f1ddbfeddabef1d55e493bd
josh-filter ":prefix=library/compiler-builtins" FETCH_HEAD
git merge --allow-unrelated FILTERED_HEAD
The HEAD in the `compiler-builtins` repository is 233434412f ("fix an if
statement that can be collapsed").
[1]: https://github.com/josh-project/josh
Use ccache for stage0 tool builds
Now after the stage0 redesign, we can actually start ccaching the build of the compiler itself. We can also cache the bootstrap tools, since these are also built with the stage0 compiler.
Stage0 compiler builds are now being cached: https://github.com/rust-lang/rust/actions/runs/15397246267#summary-43321151192 (`..bootstrap::core::build_steps::compile::Rustc 483.10s 40.41s -91.6%`). It's not a gigantic win everywhere, but it should help. It seems to make the Linux jobs ~10 minute faster. It should be especially useful on PR builds after https://github.com/rust-lang/rust/pull/141948.
r? `@jieyouxu`
try-job: `x86_64-gnu-llvm-19*`
try-job: `x86_64-msvc*`
try-job: `x86_64-apple*`
try-job: `dist-x86_64-linux`
tools-aux ci runner: also cross-test doctests in Miri
Miri now supports running doctests across different targets. Let's use that to run the std doctests on aarch64-apple-darwin, i686-pc-windows-msvc.
try-job: x86_64-gnu-aux
Warn when gold was used as the linker
gold has been deprecated recently and is known to behave incorrectly around Rust programs, including miscompiling `#[used(linker)]`. Tell people to switch to a different linker instead.
closesrust-lang/rust#141748
r? bjorn3
Optionally don't steal the THIR
The THIR being stolen is a recurrent pain for authors of rustc drivers. This makes it optional, so that the `thir_body` query can still be used after analysis of the crate has completed.
Fix citool tests when executed locally
They couldn't be executed locally before due to some additional environment reads.
I also investigated the annoying rebuilds that we see on CI all the time, and they are caused by `ring`'s build script. It should be fixed in the next ring release (https://github.com/briansmith/ring/issues/2525), so we can just wait for that and then update `ring`.
r? `@marcoieni`
allow macro_use as first segment
Fixesrust-lang/rust#140255
This issue may raise a question: It's reasonable an external crate name or import target be legally named `macro_use`?