Merge ref '0e95a0f4c677' from rust-lang/rust

Pull recent changes from https://github.com/rust-lang/rust via Josh.

Upstream ref: rust-lang/rust@0e95a0f
Filtered ref: rust-lang/compiler-builtins@84dcb0e
Upstream diff: rust-lang/rust@db3e99b...0e95a0f

This merge was created using https://github.com/rust-lang/josh-sync.

Author: The rustc-josh-sync Cronjob Bot

ci/date-check/src/main.rs

@@ -163,6 +163,9 @@ fn main() {
             }
         }
         println!();
+
+        println!("@rustbot label +C-date-reference-triage +E-easy +E-help-wanted");
+        println!();
     }
 }
 

ci/sembr/src/main.rs

@@ -15,7 +15,7 @@ struct Cli {
     /// Modify files that do not comply
     overwrite: bool,
     /// Applies to lines that are to be split
-    #[arg(long, default_value_t = 100)]
+    #[arg(long, default_value_t = 80)]
     line_length_limit: usize,
 }
 
@@ -159,6 +159,9 @@ fn lengthen_lines(content: &str, limit: usize) -> String {
         if in_html_div {
             continue;
         }
+        if line.trim_end().ends_with("<br>") {
+            continue;
+        }
         if ignore(line, in_code_block) || REGEX_SPLIT.is_match(line) {
             continue;
         }

examples/rustc-interface-example.rs

@@ -4,14 +4,12 @@
 
 extern crate rustc_driver;
 extern crate rustc_error_codes;
-extern crate rustc_errors;
 extern crate rustc_hash;
 extern crate rustc_hir;
 extern crate rustc_interface;
 extern crate rustc_session;
 extern crate rustc_span;
 
-use rustc_errors::registry;
 use rustc_hash::FxHashMap;
 use rustc_session::config;
 
@@ -30,12 +28,11 @@ fn main() {
     println!("{HELLO}");
 }
 "#
-            .into(),
+                .into(),
         },
-        output_dir: None,  // Option<PathBuf>
-        output_file: None, // Option<PathBuf>
-        file_loader: None, // Option<Box<dyn FileLoader + Send + Sync>>
-        locale_resources: rustc_driver::DEFAULT_LOCALE_RESOURCES.to_owned(),
+        output_dir: None,                // Option<PathBuf>
+        output_file: None,               // Option<PathBuf>
+        file_loader: None,               // Option<Box<dyn FileLoader + Send + Sync>>
         lint_caps: FxHashMap::default(), // FxHashMap<lint::LintId, lint::Level>
         // This is a callback from the driver that is called when [`ParseSess`] is created.
         psess_created: None, //Option<Box<dyn FnOnce(&mut ParseSess) + Send>>
@@ -50,8 +47,6 @@ fn main() {
         //
         // The second parameter is local providers and the third parameter is external providers.
         override_queries: None, // Option<fn(&Session, &mut ty::query::Providers<'_>, &mut ty::query::Providers<'_>)>
-        // Registry of diagnostics codes.
-        registry: registry::Registry::new(rustc_errors::codes::DIAGNOSTICS),
         make_codegen_backend: None,
         expanded_args: Vec::new(),
         ice_file: None,
@@ -77,4 +72,4 @@ fn main() {
             }
         });
     });
-}
+}

examples/rustc-interface-getting-diagnostics.rs

@@ -15,7 +15,7 @@ extern crate rustc_span;
 use std::sync::{Arc, Mutex};
 
 use rustc_errors::emitter::Emitter;
-use rustc_errors::registry::{self, Registry};
+use rustc_errors::registry::Registry;
 use rustc_errors::translation::Translate;
 use rustc_errors::{DiagInner, FluentBundle};
 use rustc_session::config;
@@ -59,14 +59,13 @@ fn main() {
     let x: &str = 1;
 }
 "
-            .into(),
+                .into(),
         },
         crate_cfg: Vec::new(),
         crate_check_cfg: Vec::new(),
         output_dir: None,
         output_file: None,
         file_loader: None,
-        locale_resources: rustc_driver::DEFAULT_LOCALE_RESOURCES.to_owned(),
         lint_caps: rustc_hash::FxHashMap::default(),
         psess_created: Some(Box::new(|parse_sess| {
             parse_sess.dcx().set_emitter(Box::new(DebugEmitter {
@@ -76,7 +75,6 @@ fn main() {
         })),
         register_lints: None,
         override_queries: None,
-        registry: registry::Registry::new(rustc_errors::codes::DIAGNOSTICS),
         make_codegen_backend: None,
         expanded_args: Vec::new(),
         ice_file: None,
@@ -99,4 +97,4 @@ fn main() {
     buffer.lock().unwrap().iter().for_each(|diagnostic| {
         println!("{diagnostic:#?}");
     });
-}
+}

rust-version

@@ -1 +1 @@
-44e34e1ac6d7e69b40856cf1403d3da145319c30
+562dee4820c458d823175268e41601d4c060588a

src/SUMMARY.md

@@ -124,7 +124,7 @@
     - [`#[test]` implementation](./test-implementation.md)
     - [Panic implementation](./panic-implementation.md)
     - [AST validation](./ast-validation.md)
-    - [Feature gate checking](./feature-gate-ck.md)
+    - [Feature gate checking](./feature-gate-check.md)
     - [Lang Items](./lang-items.md)
 - [The HIR (High-level IR)](./hir.md)
     - [Lowering AST to HIR](./hir/lowering.md)

src/about-this-guide.md

@@ -10,7 +10,7 @@ There are several parts to this guide:
    about building, debugging, profiling, etc.
 1. [Contributing to Rust][p2]:
    Contains information that should be useful no matter how you are contributing,
-   about procedures for contribution, using git and Github, stabilizing features, etc.
+   about procedures for contribution, using git and GitHub, stabilizing features, etc.
 1. [Bootstrapping][p3]:
    Describes how the Rust compiler builds itself using previous versions, including
    an introduction to the bootstrap process and debugging methods.

src/autodiff/installation.md

@@ -1,6 +1,50 @@
 # Installation
 
-In the near future, `std::autodiff` should become available in nightly builds for users. As a contributor however, you will still need to build rustc from source. Please be aware that the msvc target is not supported at the moment, all other tier 1 targets should work. Please open an issue if you encounter any problems on a supported tier 1 target, or if you successfully build this project on a tier2/tier3 target.
+In the near future, `std::autodiff` should become available for users via rustup. As a rustc/enzyme/autodiff contributor however, you will still need to build rustc from source. 
+For the meantime, you can download up-to-date builds to enable `std::autodiff` on your latest nightly toolchain, if you are using either of:  
+**Linux**, with `x86_64-unknown-linux-gnu` or `aarch64-unknown-linux-gnu`  
+**Windows**, with `x86_64-llvm-mingw` or `aarch64-llvm-mingw`  
+
+You can also download slightly outdated builds for **Apple** (aarch64-apple), which should generally work for now. 
+
+If you need any other platform, you can build rustc including autodiff from source. Please open an issue if you want to help enabling automatic builds for your prefered target.
+
+## Installation guide
+
+If you want to use `std::autodiff` and don't plan to contribute PR's to the project, then we recommend to just use your existing nightly installation and download the missing component. In the future, rustup will be able to do it for you.
+For now, you'll have to manually download and copy it.
+
+1) On our github repository, find the last merged PR: [`Repo`]
+2) Scroll down to the lower end of the PR, where you'll find a rust-bors message saying `Test successful` with a `CI` link. 
+3) Click on the `CI` link, and grep for your target. E.g. `dist-x86_64-linux` or `dist-aarch64-llvm-mingw` and click `Load summary`. 
+4) Under the `CI artifacts` section, find the `enzyme-nightly` artifact, download, and unpack it.
+5) Copy the artifact (libEnzyme-22.so for linux, libEnzyme-22.dylib for apple, etc.), which should be in a folder named `enzyme-preview`, to your rust toolchain directory. E.g. for linux: `cp  ~/Downloads/enzyme-nightly-x86_64-unknown-linux-gnu/enzyme-preview/lib/rustlib/x86_64-unknown-linux-gnu/lib/libEnzyme-22.so ~/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib`
+
+Apple support was temporarily reverted, due to downstream breakages. If you want to download autodiff for apple, please look at the artifacts from this [`run`].
+
+## Installation guide for Nix user.
+
+This setup was recommended by a nix and autodiff user. It uses [`Overlay`]. Please verify for yourself if you are comfortable using that repository.
+In that case you might use the following nix configuration to get a rustc that supports `std::autodiff`.
+```nix
+{
+  enzymeLib = pkgs.fetchzip {
+    url = "https://ci-artifacts.rust-lang.org/rustc-builds/ec818fda361ca216eb186f5cf45131bd9c776bb4/enzyme-nightly-x86_64-unknown-linux-gnu.tar.xz";
+    sha256 = "sha256-Rnrop44vzS+qmYNaRoMNNMFyAc3YsMnwdNGYMXpZ5VY=";
+  };
+  
+  rustToolchain = pkgs.symlinkJoin {
+    name = "rust-with-enzyme";
+    paths = [pkgs.rust-bin.nightly.latest.default];
+    nativeBuildInputs = [pkgs.makeWrapper];
+    postBuild = ''
+      libdir=$out/lib/rustlib/x86_64-unknown-linux-gnu/lib
+      cp ${enzymeLib}/enzyme-preview/lib/rustlib/x86_64-unknown-linux-gnu/lib/libEnzyme-22.so $libdir/
+      wrapProgram $out/bin/rustc --add-flags "--sysroot $out"
+    '';
+  };
+}
+```
 
 ## Build instructions
 
@@ -87,3 +131,6 @@ ninja
 ```
 This will build Enzyme, and you can find it in `Enzyme/enzyme/build/lib/<LLD/Clang/LLVM/lib>Enzyme.so`. (Endings might differ based on your OS).
 
+[`Repo`]: https://github.com/rust-lang/rust/
+[`run`]: https://github.com/rust-lang/rust/pull/153026#issuecomment-3950046599
+[`Overlay`]: https://github.com/oxalica/rust-overlay

src/backend/updating-llvm.md

@@ -1,12 +1,16 @@
 # Updating LLVM
 
-<!-- date-check: Aug 2024 -->
 Rust supports building against multiple LLVM versions:
 
 * Tip-of-tree for the current LLVM development branch is usually supported within a few days.
   PRs for such fixes are tagged with `llvm-main`.
 * The latest released major version is always supported.
-* The one or two preceding major versions are usually supported.
+* The one or two preceding major versions are usually supported in the sense that they are expected
+  to build successfully and pass most tests.
+  However, fixes for miscompilations often do not get
+  backported to past LLVM versions, so using rustc with older versions of LLVM comes with an
+  increased risk of soundness bugs.
+  We strongly recommend using the latest version of LLVM.
 
 By default, Rust uses its own fork in the [rust-lang/llvm-project repository].
 This fork is based on a `release/$N.x` branch of the upstream project, where
@@ -86,7 +90,6 @@ An example PR: [#59089](https://github.com/rust-lang/rust/pull/59089)
 
 ## New LLVM Release Updates
 
-<!-- date-check: Jul 2023 -->
 
 Unlike bugfixes,
 updating to a new release of LLVM typically requires a lot more work.
@@ -167,12 +170,14 @@ so let's go through each in detail.
    You'll change at least
    `src/llvm-project` and will likely also change [`llvm-wrapper`] as well.
 
-   <!-- date-check: mar 2025 -->
+   <!-- date-check: March 2026 -->
    > For prior art, here are some previous LLVM updates:
    > - [LLVM 17](https://github.com/rust-lang/rust/pull/115959)
    > - [LLVM 18](https://github.com/rust-lang/rust/pull/120055)
    > - [LLVM 19](https://github.com/rust-lang/rust/pull/127513)
    > - [LLVM 20](https://github.com/rust-lang/rust/pull/135763)
+   > - [LLVM 21](https://github.com/rust-lang/rust/pull/143684)
+   > - [LLVM 22](https://github.com/rust-lang/rust/pull/150722)
 
    Note that sometimes it's easiest to land [`llvm-wrapper`] compatibility as a PR
    before actually updating `src/llvm-project`.