Merge pull request #4190 from rust-lang/rustup-2025-02-13

Automatic Rustup
2025-02-13 06:11:48 +00:00 · 2025-02-13 06:11:48 +00:00 · 922dbb48bf
parent 832b801d0e e4e725109c
commit 922dbb48bf
16 changed files with 159 additions and 92 deletions
--- a/.github/workflows/rustc-pull.yml
+++ b/.github/workflows/rustc-pull.yml
@ -3,8 +3,8 @@ name: rustc-pull
 on:
  workflow_dispatch:
  schedule:
-    # Run at 04:00 UTC every Monday
-    - cron: '0 4 * * 1'
+    # Run at 04:00 UTC every Monday and Thursday
+    - cron: '0 4 * * 1,4'

 jobs:
  pull:
@ -34,8 +34,25 @@ jobs:
          git config --global user.name 'The rustc-dev-guide Cronjob Bot'
          git config --global user.email 'github-actions@github.com'
      - name: Perform rustc-pull
-        run: cargo run --manifest-path josh-sync/Cargo.toml -- rustc-pull
+        id: rustc-pull
+        # Turn off -e to disable early exit
+        shell: bash {0}
+        run: |
+          cargo run --manifest-path josh-sync/Cargo.toml -- rustc-pull
+          exitcode=$?
+
+          # If no pull was performed, we want to mark this job as successful,
+          # but we do not want to perform the follow-up steps.
+          if [ $exitcode -eq 0 ]; then
+            echo "pull_result=pull-finished" >> $GITHUB_OUTPUT
+          elif [ $exitcode -eq 2 ]; then
+            echo "pull_result=skipped" >> $GITHUB_OUTPUT
+            exitcode=0
+          fi
+
+          exit ${exitcode}
      - name: Push changes to a branch
+        if: ${{ steps.rustc-pull.outputs.pull_result == 'pull-finished' }}
        run: |
          # Update a sticky branch that is used only for rustc pulls
          BRANCH="rustc-pull"
@ -43,6 +60,9 @@ jobs:
          git push -u origin $BRANCH --force
      - name: Create pull request
        id: update-pr
+        if: ${{ steps.rustc-pull.outputs.pull_result == 'pull-finished' }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          # Check if an open pull request for an rustc pull update already exists
          # If it does, the previous push has just updated it
@ -54,26 +74,35 @@ jobs:
            echo "pr_url=$PR_URL" >> $GITHUB_OUTPUT
          else
            PR_URL=`gh pr list --author github-actions[bot] --state open -q 'map(select(.title=="Rustc pull update")) | .[0].url' --json url,title`
+            echo "Updating pull request ${PR_URL}"
            echo "pr_url=$PR_URL" >> $GITHUB_OUTPUT
          fi
-        env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
  send-zulip-message:
    needs: [pull]
    if: ${{ !cancelled() }}
    runs-on: ubuntu-latest
    steps:
+      - uses: actions/checkout@v4
      - name: Compute message
-        id: message
+        id: create-message
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
-          if [ "${{ needs.pull.result }}" == "failure" ];
-          then
+          if [ "${{ needs.pull.result }}" == "failure" ]; then
            WORKFLOW_URL="${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
            echo "message=Rustc pull sync failed. Check out the [workflow URL]($WORKFLOW_URL)." >> $GITHUB_OUTPUT
          else
-            echo "message=Rustc pull sync succeeded. Check out the [PR](${{ needs.pull.outputs.pr_url }})." >> $GITHUB_OUTPUT
+            CREATED_AT=`gh pr list --author github-actions[bot] --state open -q 'map(select(.title=="Rustc pull update")) | .[0].createdAt' --json createdAt,title`
+            PR_URL=`gh pr list --author github-actions[bot] --state open -q 'map(select(.title=="Rustc pull update")) | .[0].url' --json url,title`
+            week_ago=$(date +%F -d '7 days ago')
+
+            # If there is an open PR that is at least a week old, post a message about it
+            if [[ -n $DATE_GH && $DATE_GH < $week_ago ]]; then
+              echo "message=A PR with a Rustc pull has been opened for more a week. Check out the [PR](${PR_URL})." >> $GITHUB_OUTPUT
+            fi
          fi
      - name: Send a Zulip message about updated PR
+        if: ${{ steps.create-message.outputs.message != '' }}
        uses: zulip/github-actions-zulip/send-message@e4c8f27c732ba9bd98ac6be0583096dea82feea5
        with:
          api-key: ${{ secrets.ZULIP_API_TOKEN }}
--- a/josh-sync/src/main.rs
+++ b/josh-sync/src/main.rs
@ -1,5 +1,5 @@
 use clap::Parser;
-use crate::sync::GitSync;
+use crate::sync::{GitSync, RustcPullError};

 mod sync;

@ -22,7 +22,18 @@ fn main() -> anyhow::Result<()> {
    let sync = GitSync::from_current_dir()?;
    match args {
        Args::RustcPull => {
-            sync.rustc_pull(None)?;
+            if let Err(error) = sync.rustc_pull(None) {
+                match error {
+                    RustcPullError::NothingToPull => {
+                        eprintln!("Nothing to pull");
+                        std::process::exit(2);
+                    }
+                    RustcPullError::PullFailed(error) => {
+                        eprintln!("Pull failure: {error:?}");
+                        std::process::exit(1);
+                    }
+                }
+            }
        }
        Args::RustcPush { github_username, branch } => {
            sync.rustc_push(github_username, branch)?;
--- a/josh-sync/src/sync.rs
+++ b/josh-sync/src/sync.rs
@ -11,6 +11,19 @@ const JOSH_FILTER: &str = ":/src/doc/rustc-dev-guide";
 const JOSH_PORT: u16 = 42042;
 const UPSTREAM_REPO: &str = "rust-lang/rust";

+pub enum RustcPullError {
+    /// No changes are available to be pulled.
+    NothingToPull,
+    /// A rustc-pull has failed, probably a git operation error has occurred.
+    PullFailed(anyhow::Error)
+}
+
+impl<E> From<E> for RustcPullError where E: Into<anyhow::Error> {
+    fn from(error: E) -> Self {
+        Self::PullFailed(error.into())
+    }
+}
+
 pub struct GitSync {
    dir: PathBuf,
 }
@ -24,7 +37,7 @@ impl GitSync {
        })
    }

-    pub fn rustc_pull(&self, commit: Option<String>) -> anyhow::Result<()> {
+    pub fn rustc_pull(&self, commit: Option<String>) -> Result<(), RustcPullError> {
        let sh = Shell::new()?;
        sh.change_dir(&self.dir);
        let commit = commit.map(Ok).unwrap_or_else(|| {
@ -38,7 +51,7 @@ impl GitSync {
        })?;
        // Make sure the repo is clean.
        if cmd!(sh, "git status --untracked-files=no --porcelain").read()?.is_empty().not() {
-            bail!("working directory must be clean before performing rustc pull");
+            return Err(anyhow::anyhow!("working directory must be clean before performing rustc pull").into());
        }
        // Make sure josh is running.
        let josh = Self::start_josh()?;
@ -47,7 +60,7 @@ impl GitSync {

        let previous_base_commit = sh.read_file("rust-version")?.trim().to_string();
        if previous_base_commit == commit {
-            return Err(anyhow::anyhow!("No changes since last pull"));
+            return Err(RustcPullError::NothingToPull);
        }

        // Update rust-version file. As a separate commit, since making it part of
@ -94,12 +107,13 @@ impl GitSync {
            cmd!(sh, "git reset --hard HEAD^")
                .run()
                .expect("FAILED to clean up after creating the preparation commit");
-            return Err(anyhow::anyhow!("No merge was performed, nothing to pull. Rolled back the preparation commit."));
+            eprintln!("No merge was performed, no changes to pull were found. Rolled back the preparation commit.");
+            return Err(RustcPullError::NothingToPull);
        }

        // Check that the number of roots did not increase.
        if num_roots()? != num_roots_before {
-            bail!("Josh created a new root commit. This is probably not the history you want.");
+            return Err(anyhow::anyhow!("Josh created a new root commit. This is probably not the history you want.").into());
        }

        drop(josh);
--- a/2
+++ b/2
@ -1 +1 @@
-66d6064f9eb888018775e08f84747ee6f39ba28e
+124cc92199ffa924f6b4c7cc819a85b65e0c3984
--- a/src/appendix/bibliography.md
+++ b/src/appendix/bibliography.md
@ -82,7 +82,7 @@ Rust, as well as publications about Rust.
 * [Ownership is Theft: Experiences Building an Embedded OS in Rust - Amit Levy, et. al.](https://amitlevy.com/papers/tock-plos2015.pdf)
 * [You can't spell trust without Rust](https://faultlore.com/blah/papers/thesis.pdf). Aria Beingessner's master's thesis.
 * [Rust-Bio: a fast and safe bioinformatics library](https://rust-bio.github.io/). Johannes Köster
-* [Safe, Correct, and Fast Low-Level Networking](https://octarineparrot.com/assets/msci_paper.pdf). Robert Clipsham's master's thesis.
+* [Safe, Correct, and Fast Low-Level Networking](https://csperkins.org/research/thesis-msci-clipsham.pdf). Robert Clipsham's master's thesis.
 * [Formalizing Rust traits](https://open.library.ubc.ca/cIRcle/collections/ubctheses/24/items/1.0220521). Jonatan Milewski's master's thesis.
 * [Rust as a Language for High Performance GC Implementation](https://dl.acm.org/doi/pdf/10.1145/3241624.2926707)
 * [Simple Verification of Rust Programs via Functional Purification](https://github.com/Kha/electrolysis). Sebastian Ullrich's master's thesis.
--- a/src/building/suggested.md
+++ b/src/building/suggested.md
@ -135,24 +135,24 @@ and follow the same instructions as above.
 ### Emacs

 Emacs provides support for rust-analyzer with project-local configuration
-through [Eglot](https://www.gnu.org/software/emacs/manual/html_node/eglot/).  
+through [Eglot](https://www.gnu.org/software/emacs/manual/html_node/eglot/).
 Steps for setting up Eglot with rust-analyzer can be [found
-here](https://rust-analyzer.github.io/manual.html#eglot).  
+here](https://rust-analyzer.github.io/manual.html#eglot).
 Having set up Emacs & Eglot for Rust development in general, you can run
 `./x setup editor` and select `emacs`, which will prompt you to create
 `.dir-locals.el` with the recommended configuration for Eglot.
-The recommended settings live at [`src/etc/rust_analyzer_eglot.el`].  
+The recommended settings live at [`src/etc/rust_analyzer_eglot.el`].
 For more information on project-specific Eglot configuration, consult [the
 manual](https://www.gnu.org/software/emacs/manual/html_node/eglot/Project_002dspecific-configuration.html).

 ### Helix

-Helix comes with built-in LSP and rust-analyzer support.  
+Helix comes with built-in LSP and rust-analyzer support.
 It can be configured through `languages.toml`, as described
-[here](https://docs.helix-editor.com/languages.html).  
+[here](https://docs.helix-editor.com/languages.html).
 You can run `./x setup editor` and select `helix`, which will prompt you to
 create `languages.toml` with the recommended configuration for Helix. The
-recommended settings live at [`src/etc/rust_analyzer_helix.toml`].  
+recommended settings live at [`src/etc/rust_analyzer_helix.toml`].

 ## Check, check, and check again

@ -181,7 +181,7 @@ example, running `tidy` and `linkchecker` is useful when editing Markdown files,
 whereas UI tests are much less likely to be helpful. While `x suggest` is a
 useful tool, it does not guarantee perfect coverage (just as PR CI isn't a
 substitute for bors). See the [dedicated chapter](../tests/suggest-tests.md) for
-more information and contribution instructions. 
+more information and contribution instructions.

 Please note that `x suggest` is in a beta state currently and the tests that it
 will suggest are limited.
@ -332,28 +332,21 @@ git worktree add -b my-feature ../rust2 master
 You can then use that rust2 folder as a separate workspace for modifying and
 building `rustc`!

-## Using nix-shell
+## Working with nix

-If you're using nix, you can use the following nix-shell to work on Rust:
+Several nix configurations are defined in `src/tools/nix-dev-shell`.

-```nix
-{ pkgs ? import <nixpkgs> {} }:
-pkgs.mkShell {
-  name = "rustc";
-  nativeBuildInputs = with pkgs; [
-    binutils cmake ninja pkg-config python3 git curl cacert patchelf nix
-  ];
-  buildInputs = with pkgs; [
-    openssl glibc.out glibc.static
-  ];
-  # Avoid creating text files for ICEs.
-  RUSTC_ICE = "0";
-  # Provide `libstdc++.so.6` for the self-contained lld.
-  LD_LIBRARY_PATH = "${with pkgs; lib.makeLibraryPath [
-    stdenv.cc.cc.lib
-  ]}";
-}
+If you're using direnv, you can create a symbol link to `src/tools/nix-dev-shell/envrc-flake` or `src/tools/nix-dev-shell/envrc-shell`
+
+```bash
+ln -s ./src/tools/nix-dev-shell/envrc-flake ./.envrc # Use flake
 ```
+or
+```bash
+ln -s ./src/tools/nix-dev-shell/envrc-shell ./.envrc # Use nix-shell
+```
+
+### Note

 Note that when using nix on a not-NixOS distribution, it may be necessary to set
 **`patch-binaries-for-nix = true` in `config.toml`**. Bootstrap tries to detect
--- a/src/diagnostics.md
+++ b/src/diagnostics.md
@ -601,8 +601,8 @@ The trait implementation allows you to check certain syntactic constructs
 as the linter walks the AST. You can then choose to emit lints in a
 very similar way to compile errors.

-You also declare the metadata of a particular lint via the `declare_lint!`
-macro. [This macro](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_lint_defs/macro.declare_lint.html) includes the name, the default level, a short description, and some
+You also declare the metadata of a particular lint via the [`declare_lint!`]
+macro. This macro includes the name, the default level, a short description, and some
 more details.

 Note that the lint and the lint pass must be registered with the compiler.
@ -671,6 +671,8 @@ example-use-loop = denote infinite loops with `loop {"{"} ... {"}"}`
  .suggestion = use `loop`
 ```

+[`declare_lint!`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_lint_defs/macro.declare_lint.html
+
 ### Edition-gated lints

 Sometimes we want to change the behavior of a lint in a new edition. To do this,
--- a/src/getting-started.md
+++ b/src/getting-started.md
@ -101,7 +101,6 @@ it's easy to pick up work without a large time commitment:
 - [Rustdoc Askama Migration](https://github.com/rust-lang/rust/issues/108868)
 - [Diagnostic Translation](https://github.com/rust-lang/rust/issues/100717)
 - [Move UI tests to subdirectories](https://github.com/rust-lang/rust/issues/73494)
- [Port run-make tests from Make to Rust](https://github.com/rust-lang/rust/issues/121876)

 If you find more recurring work, please feel free to add it here!

--- a/src/implementing_new_features.md
+++ b/src/implementing_new_features.md
@ -9,7 +9,11 @@ smoothly.
 **NOTE: this section is for *language* features, not *library* features,
 which use [a different process].**

+See also [the Rust Language Design Team's procedures][lang-propose] for
+proposing changes to the language.
+
 [a different process]: ./stability.md
+[lang-propose]: https://lang-team.rust-lang.org/how_to/propose.html

 ## The @rfcbot FCP process

--- a/src/param_env/param_env_acquisition.md
+++ b/src/param_env/param_env_acquisition.md
@ -21,7 +21,7 @@ Creating an env from an arbitrary set of where clauses is usually unnecessary an

 Creating an empty environment via `ParamEnv::empty` is almost always wrong. There are very few places where we actually know that the environment should be empty. One of the only places where we do actually know this is after monomorphization, however the `ParamEnv` there should be constructed via `ParamEnv::reveal_all` instead as at this point we should be able to determine the hidden type of opaque types. Codegen/Post-mono is one of the only places that should be using `ParamEnv::reveal_all`.

-An additional piece of complexity here is specifying the [`Reveal`][reveal] (see linked docs for explanation of what reveal does) used for the `ParamEnv`. When constructing a param env using the `param_env` query it will have `Reveal::UserFacing`, if `Reveal::All` is desired then the [`tcx.param_env_reveal_all_normalized`][env_reveal_all_normalized] query can be used instead.
+An additional piece of complexity here is specifying the `Reveal` (see linked docs for explanation of what reveal does) used for the `ParamEnv`. When constructing a param env using the `param_env` query it will have `Reveal::UserFacing`, if `Reveal::All` is desired then the [`tcx.param_env_reveal_all_normalized`][env_reveal_all_normalized] query can be used instead.

 The `ParamEnv` type has a method [`ParamEnv::with_reveal_all_normalized`][with_reveal_all] which converts an existing `ParamEnv` into one with `Reveal::All` specified. Where possible the previously mentioned query should be preferred as it is more efficient.

@ -38,7 +38,6 @@ The `ParamEnv` type has a method [`ParamEnv::with_reveal_all_normalized`][with_r
 [with_reveal_all]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/struct.ParamEnv.html#method.with_reveal_all_normalized
 [env_reveal_all]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/struct.ParamEnv.html#method.reveal_all
 [env_empty]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/struct.ParamEnv.html#method.empty
-[reveal]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_infer/traits/enum.Reveal.html
 [pe]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/struct.ParamEnv.html
 [param_env_query]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_hir_typeck/fn_ctxt/struct.FnCtxt.html#structfield.param_env
 [method_pred_entailment]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_hir_analysis/check/compare_impl_item/fn.compare_method_predicate_entailment.html
--- a/src/param_env/param_env_what_is_it.md
+++ b/src/param_env/param_env_what_is_it.md
@ -3,7 +3,7 @@

 The type system relies on information in the environment in order for it to function correctly. This information is stored in the [`ParamEnv`][pe] type and it is important to use the correct `ParamEnv` when interacting with the type system.

-The information represented by `ParamEnv` is a list of in-scope where-clauses, and a [`Reveal`][reveal] (see linked docs for more information). A `ParamEnv` typically corresponds to a specific item's where clauses, some clauses are not explicitly written bounds and instead are implicitly added in [`predicates_of`][predicates_of] such as `ConstArgHasType` or some implied bounds.
+The information represented by `ParamEnv` is a list of in-scope where-clauses, and a `Reveal` (see linked docs for more information). A `ParamEnv` typically corresponds to a specific item's where clauses, some clauses are not explicitly written bounds and instead are implicitly added in [`predicates_of`][predicates_of] such as `ConstArgHasType` or some implied bounds.

 A `ParamEnv` can also be created with arbitrary data that is not derived from a specific item such as in [`compare_method_predicate_entailment`][method_pred_entailment] which creates a hybrid `ParamEnv` consisting of the impl's where clauses and the trait definition's function's where clauses. In most cases `ParamEnv`s are initially created via the [`param_env` query][query] which returns a `ParamEnv` derived from the provided item's where clauses.

@ -57,4 +57,3 @@ It's very important to use the correct `ParamEnv` when interacting with the type
 [method_pred_entailment]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_hir_analysis/check/compare_impl_item/fn.compare_method_predicate_entailment.html
 [pe]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/struct.ParamEnv.html
 [query]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/context/struct.TyCtxt.html#method.param_env
-[reveal]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_infer/traits/enum.Reveal.html
--- a/src/rustdoc-internals/search.md
+++ b/src/rustdoc-internals/search.md
@ -46,8 +46,8 @@ For space savings, it's also written without newlines or spaces.
 ]
 ```

-[`src/librustdoc/html/static/js/externs.js`]
-defines an actual schema in a Closure `@typedef`.
+[`src/librustdoc/html/static/js/rustdoc.d.ts`]
+defines an actual schema in a TypeScript `type`.

 | Key | Name                 | Description  |
 | --- | -------------------- | ------------ |
@ -68,7 +68,7 @@ with a free function called `function_name` and a struct called `Data`,
 with the type signature `Data, i32 -> str`,
 and an alias, `get_name`, that equivalently refers to `function_name`.

-[`src/librustdoc/html/static/js/externs.js`]: https://github.com/rust-lang/rust/blob/79b710c13968a1a48d94431d024d2b1677940866/src/librustdoc/html/static/js/externs.js#L204-L258
+[`src/librustdoc/html/static/js/rustdoc.d.ts`]: https://github.com/rust-lang/rust/blob/2f92f050e83bf3312ce4ba73c31fe843ad3cbc60/src/librustdoc/html/static/js/rustdoc.d.ts#L344-L390

 The search index needs to fit the needs of the `rustdoc` compiler,
 the `search.js` frontend,
@ -469,7 +469,7 @@ want the libs team to be able to add new items without causing unrelated
 tests to fail, but standalone tests will use it more often.

 The `ResultsTable` and `ParsedQuery` types are specified in
-[`externs.js`](https://github.com/rust-lang/rust/blob/master/src/librustdoc/html/static/js/externs.js).
+[`rustdoc.d.ts`](https://github.com/rust-lang/rust/blob/master/src/librustdoc/html/static/js/rustdoc.d.ts).

 For example, imagine we needed to fix a bug where a function named
 `constructor` couldn't be found. To do this, write two files:
--- a/src/tests/ci.md
+++ b/src/tests/ci.md
@ -322,7 +322,7 @@ Our CI workflow uses various caching mechanisms, mainly for two things:
 ### Docker images caching

 The Docker images we use to run most of the Linux-based builders take a *long*
-time to fully build. To speed up the build, we cache it using [Docker registry
+time to fully build. To speed up the build, we cache them using [Docker registry
 caching], with the intermediate artifacts being stored on [ghcr.io]. We also
 push the built Docker images to ghcr, so that they can be reused by other tools
 (rustup) or by developers running the Docker build locally (to speed up their
@ -334,6 +334,13 @@ override the cache for the others. Instead, we store the images under different
 tags, identifying them with a custom hash made from the contents of all the
 Dockerfiles and related scripts.

+The CI calculates a hash key, so that the cache of a Docker image is
+invalidated if one of the following changes:
+
+- Dockerfile
+- Files copied into the Docker image in the Dockerfile
+- The architecture of the GitHub runner (x86 or ARM)
+
 [ghcr.io]: https://github.com/rust-lang-ci/rust/pkgs/container/rust-ci
 [Docker registry caching]: https://docs.docker.com/build/cache/backends/registry/

@ -341,9 +348,18 @@ Dockerfiles and related scripts.

 We build some C/C++ stuff in various CI jobs, and we rely on [sccache] to cache
 the intermediate LLVM artifacts. Sccache is a distributed ccache developed by
-Mozilla, which can use an object storage bucket as the storage backend. In our
-case, the artefacts are uploaded to an S3 bucket that we control
-(`rust-lang-ci-sccache2`).
+Mozilla, which can use an object storage bucket as the storage backend.
+
+With sccache there's no need to calculate the hash key ourselves. Sccache
+invalidates the cache automatically when it detects changes to relevant inputs,
+such as the source code, the version of the compiler, and important environment
+variables.
+So we just pass the sccache wrapper on top of cargo and sccache does the rest.
+
+We store the persistent artifacts on the S3 bucket `rust-lang-ci-sccache2`. So
+when the CI runs, if sccache sees that LLVM is being compiled with the same C/C++
+compiler and the LLVM source code is the same, sccache retrieves the individual
+compiled translation units from S3.

 [sccache]: https://github.com/mozilla/sccache

--- a/src/tests/directives.md
+++ b/src/tests/directives.md
@ -192,6 +192,8 @@ settings:
  specified atomic widths, e.g. the test with `//@ needs-target-has-atomic: 8,
  16, ptr` will only run if it supports the comma-separated list of atomic
  widths.
+- `needs-dynamic-linking` - ignores if target does not support dynamic linking
+  (which is orthogonal to it being unable to create `dylib` and `cdylib` crate types)

 The following directives will check LLVM support:

--- a/src/tests/docker.md
+++ b/src/tests/docker.md
@ -1,36 +1,44 @@
 # Testing with Docker

-The Rust tree includes [Docker] image definitions for the platforms used on
-GitHub Actions in [`src/ci/docker`].
-The script [`src/ci/docker/run.sh`] is used to build the Docker image, run it,
-build Rust within the image, and run the tests.
-
-You can run these images on your local development machine. This can be
-helpful to test environments different from your local system. First you will
+The [`src/ci/docker`] directory includes [Docker] image definitions for Linux-based jobs executed on GitHub Actions (non-Linux jobs run outside Docker). You can run these jobs on your local development machine, which can be
+helpful to test environments different from your local system. You will
 need to install Docker on a Linux, Windows, or macOS system (typically Linux
 will be much faster than Windows or macOS because the latter use virtual
-machines to emulate a Linux environment). To enter interactive mode which will
-start a bash shell in the container, run `src/ci/docker/run.sh --dev <IMAGE>`
-where `<IMAGE>` is one of the directory names in `src/ci/docker` (for example
-`x86_64-gnu` is a fairly standard Ubuntu environment).
+machines to emulate a Linux environment).

-The docker script will mount your local Rust source tree in read-only mode,
-and an `obj` directory in read-write mode. All of the compiler artifacts will
-be stored in the `obj` directory. The shell will start out in the `obj`
-directory. From there, you can run `../src/ci/run.sh` which will run the build
-as defined by the image.
+Jobs running in CI are configured through a set of bash scripts, and it is not always trivial to reproduce their behavior locally. If you want to run a CI job locally in the simplest way possible, you can use a provided helper Python script that tries to replicate what happens on CI as closely as possible:

-Alternatively, you can run individual commands to do specific tasks. For
-example, you can run `../x test tests/ui` to just run UI tests.
-Note that there is some configuration in the [`src/ci/run.sh`] script that you
-may need to recreate. Particularly, set `submodules = false` in your
-`config.toml` so that it doesn't attempt to modify the read-only directory.
+```bash
+python3 src/ci/github-actions/ci.py run-local <job-name>
+# For example:
+python3 src/ci/github-actions/ci.py run-local dist-x86_64-linux-alt
+```

-Some additional notes about using the Docker images:
+If the above script does not work for you, you would like to have more control of the Docker image execution, or you want to understand what exactly happens during Docker job execution, then continue reading below.

+## The `run.sh` script
+The [`src/ci/docker/run.sh`] script is used to build a specific Docker image, run it,
+build Rust within the image, and either run tests or prepare a set of archives designed for distribution. The script will mount your local Rust source tree in read-only mode, and an `obj` directory in read-write mode. All the compiler artifacts will be stored in the `obj` directory. The shell will start out in the `obj`directory. From there, it will execute `../src/ci/run.sh` which starts the build as defined by the Docker image.
+
+You can run `src/ci/docker/run.sh <image-name>` directly. A few important notes regarding the `run.sh` script:
+- When executed on CI, the script expects that all submodules are checked out. If some submodule that is accessed by the job is not available, the build will result in an error. You should thus make sure that you have all required submodules checked out locally. You can either do that manually through git, or set `submodules = true` in your `config.toml` and run a command such as `x build` to let bootstrap download the most important submodules (this might not be enough for the given CI job that you are trying to execute though).
+- `<image-name>` corresponds to a single directory located in one of the `src/ci/docker/host-*` directories. Note that image name does not necessarily correspond to a job name, as some jobs execute the same image, but with different environment variables or Docker build arguments (this is a part of the complexity that makes it difficult to run CI jobs locally).
+- If you are executing a "dist" job (job beginning with `dist-`), you should set the `DEPLOY=1` environment variable.
+- If you are executing an "alternative dist" job (job beginning with `dist-` and ending with `-alt`), you should set the `DEPLOY_ALT=1` environment variable.
 - Some of the std tests require IPv6 support. Docker on Linux seems to have it
  disabled by default. Run the commands in [`enable-docker-ipv6.sh`] to enable
  IPv6 before creating the container. This only needs to be done once.
+
+### Interactive mode
+
+Sometimes, it can be useful to build a specific Docker image, and then run custom commands inside it, so that you can experiment with how the given system behaves. You can do that using an interactive mode, which will
+start a bash shell in the container, using `src/ci/docker/run.sh --dev <image-name>`.
+
+When inside the Docker container, you can run individual commands to do specific tasks. For
+example, you can run `../x test tests/ui` to just run UI tests.
+
+Some additional notes about using the interactive mode:
+
 - The container will be deleted automatically when you exit the shell, however
  the build artifacts persist in the `obj` directory. If you are switching
  between different Docker images, the artifacts from previous environments
@ -45,15 +53,6 @@ Some additional notes about using the Docker images:
  containers. With the container name, run `docker exec -it <CONTAINER>
  /bin/bash` where `<CONTAINER>` is the container name like `4ba195e95cef`.

-The approach described above is a relatively low-level interface for running the Docker images
-directly. If you want to run a full CI Linux job locally with Docker, in a way that is as close to CI as possible, you can use the following command:
-
-```bash
-python3 src/ci/github-actions/ci.py run-local <job-name>
-# For example:
-python3 src/ci/github-actions/ci.py run-local dist-x86_64-linux-alt
-```
-
 [Docker]: https://www.docker.com/
 [`src/ci/docker`]: https://github.com/rust-lang/rust/tree/master/src/ci/docker
 [`src/ci/docker/run.sh`]: https://github.com/rust-lang/rust/blob/master/src/ci/docker/run.sh
--- a/src/traits/implied-bounds.md
+++ b/src/traits/implied-bounds.md
@ -40,7 +40,7 @@ requirements of impls and functions as explicit predicates.
 ### using implicit implied bounds as assumptions

 These bounds are not added to the `ParamEnv` of the affected item itself. For lexical
-region resolution they are added using [`fn OutlivesEnvironment::new`].
+region resolution they are added using [`fn OutlivesEnvironment::from_normalized_bounds`].
 Similarly, during MIR borrowck we add them using
 [`fn UniversalRegionRelationsBuilder::add_implied_bounds`].

@ -55,7 +55,7 @@ The assumed outlives constraints for implicit bounds are computed using the
 MIR borrowck adds the outlives constraints for both the normalized and unnormalized types,
 lexical region resolution [only uses the unnormalized types][notnorm].

-[`fn OutlivesEnvironment::new`]: TODO
+[`fn OutlivesEnvironment::from_normalized_bounds`]: https://github.com/rust-lang/rust/blob/8239a37f9c0951a037cfc51763ea52a20e71e6bd/compiler/rustc_infer/src/infer/outlives/env.rs#L50-L55
 [`fn UniversalRegionRelationsBuilder::add_implied_bounds`]: https://github.com/rust-lang/rust/blob/5b8bc568d28b2e922290c9a966b3231d0ce9398b/compiler/rustc_borrowck/src/type_check/free_region_relations.rs#L316
 [mir]: https://github.com/rust-lang/rust/blob/91cae1dcdcf1a31bd8a92e4a63793d65cfe289bb/compiler/rustc_borrowck/src/type_check/free_region_relations.rs#L258-L332
 [`fn assumed_wf_types`]: https://github.com/rust-lang/rust/blob/5b8bc568d28b2e922290c9a966b3231d0ce9398b/compiler/rustc_ty_utils/src/implied_bounds.rs#L21