Merge pull request #18566 from lnicola/sync-from-rust

minor: Sync from downstream

Author: lnicola

.cargo/config.toml

@@ -58,11 +58,20 @@ jobs:
       - name: rustdoc
         run: RUSTDOCFLAGS="-Dwarnings" ./miri doc --document-private-items
 
+  coverage:
+    name: coverage report
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./.github/workflows/setup
+      - name: coverage
+        run: ./miri test --coverage
+
   # Summary job for the merge queue.
   # ALL THE PREVIOUS JOBS NEED TO BE ADDED TO THE `needs` SECTION OF THIS JOB!
   # And they should be added below in `cron-fail-notify` as well.
   conclusion:
-    needs: [build, style]
+    needs: [build, style, coverage]
     # We need to ensure this job does *not* get skipped if its dependencies fail,
     # because a skipped job is considered a success by GitHub. So we have to
     # overwrite `if:`. We use `!cancelled()` to ensure the job does still not get run
@@ -86,7 +95,7 @@ jobs:
         contents: write
         # ... and create a PR.
         pull-requests: write
-    needs: [build, style]
+    needs: [build, style, coverage]
     if: ${{ github.event_name == 'schedule' && failure() }}
     steps:
       # Send a Zulip notification

.github/workflows/ci.yml

@@ -13,6 +13,25 @@ for a list of Miri maintainers.
 
 [Rust Zulip]: https://rust-lang.zulipchat.com
 
+### Pull review process
+
+When you get a review, please take care of the requested changes in new commits. Do not amend
+existing commits. Generally avoid force-pushing. The only time you should force push is when there
+is a conflict with the master branch (in that case you should rebase across master, not merge), and
+all the way at the end of the review process when the reviewer tells you that the PR is done and you
+should squash the commits. For the latter case, use `git rebase --keep-base ...` to squash without
+changing the base commit your PR branches off of. Use your own judgment and the reviewer's guidance
+to decide whether the PR should be squashed into a single commit or multiple logically separate
+commits. (All this is to work around the fact that Github is quite bad at dealing with force pushes
+and does not support `git range-diff`. Maybe one day Github will be good at git and then life can
+become easier.)
+
+Most PRs bounce back and forth between the reviewer and the author several times, so it is good to
+keep track of who is expected to take the next step. We are using the `S-waiting-for-review` and
+`S-waiting-for-author` labels for that. If a reviewer asked you to do some changes and you think
+they are all taken care of, post a comment saying `@rustbot ready` to mark a PR as ready for the
+next round of review.
+
 ### Larger-scale contributions
 
 If you are thinking about making a larger-scale contribution -- in particular anything that needs
@@ -45,14 +64,6 @@ process for such contributions:
 This process is largely informal, and its primary goal is to more clearly communicate expectations.
 Please get in touch with us if you have any questions!
 
-### Managing the review state
-
-Most PRs bounce back and forth between the reviewer and the author several times, so it is good to
-keep track of who is expected to take the next step. We are using the `S-waiting-for-review` and
-`S-waiting-for-author` labels for that. If a reviewer asked you to do some changes and you think
-they are all taken care of, post a comment saying `@rustbot ready` to mark a PR as ready for the
-next round of review.
-
 ## Preparing the build environment
 
 Miri heavily relies on internal and unstable rustc interfaces to execute MIR,

CONTRIBUTING.md

@@ -548,6 +548,7 @@ Definite bugs found:
 * [Incorrect offset computation for highly-aligned types in `portable-atomic-util`](https://github.com/taiki-e/portable-atomic/pull/138)
 * [Occasional memory leak in `std::mpsc` channels](https://github.com/rust-lang/rust/issues/121582) (original code in [crossbeam](https://github.com/crossbeam-rs/crossbeam/pull/1084))
 * [Weak-memory-induced memory leak in Windows thread-local storage](https://github.com/rust-lang/rust/pull/124281)
+* [A bug in the new `RwLock::downgrade` implementation](https://rust-lang.zulipchat.com/#narrow/channel/269128-miri/topic/Miri.20error.20library.20test) (caught by Miri before it landed in the Rust repo)
 
 Violations of [Stacked Borrows] found that are likely bugs (but Stacked Borrows is currently just an experiment):
 

README.md

@@ -154,7 +154,7 @@ case $HOST_TARGET in
     TEST_TARGET=i686-unknown-freebsd   run_tests_minimal $BASIC $UNIX time hashmap random threadname pthread fs libc-pipe
     TEST_TARGET=x86_64-unknown-illumos run_tests_minimal $BASIC $UNIX time hashmap random thread sync available-parallelism tls libc-pipe
     TEST_TARGET=x86_64-pc-solaris      run_tests_minimal $BASIC $UNIX time hashmap random thread sync available-parallelism tls libc-pipe
-    TEST_TARGET=aarch64-linux-android  run_tests_minimal $BASIC $UNIX time hashmap threadname pthread
+    TEST_TARGET=aarch64-linux-android  run_tests_minimal $BASIC $UNIX time hashmap random sync threadname pthread
     TEST_TARGET=wasm32-wasip2          run_tests_minimal $BASIC wasm
     TEST_TARGET=wasm32-unknown-unknown run_tests_minimal no_std empty_main wasm # this target doesn't really have std
     TEST_TARGET=thumbv7em-none-eabihf  run_tests_minimal no_std

ci/ci.sh

@@ -1 +1 @@
-arithmetic-side-effects-allowed = ["rustc_target::abi::Size"]
+arithmetic-side-effects-allowed = ["rustc_abi::Size", "rustc_apfloat::ieee::IeeeFloat"]

clippy.toml

@@ -1,13 +1,15 @@
 #!/usr/bin/env bash
 set -e
 # We want to call the binary directly, so we need to know where it ends up.
-MIRI_SCRIPT_TARGET_DIR="$(dirname "$0")"/miri-script/target
+ROOT_DIR="$(dirname "$0")"
+MIRI_SCRIPT_TARGET_DIR="$ROOT_DIR"/miri-script/target
 # If stdout is not a terminal and we are not on CI, assume that we are being invoked by RA, and use JSON output.
 if ! [ -t 1 ] && [ -z "$CI" ]; then
   MESSAGE_FORMAT="--message-format=json"
 fi
-# We need a nightly toolchain, for the `profile-rustflags` cargo feature.
-cargo +nightly build $CARGO_EXTRA_FLAGS --manifest-path "$(dirname "$0")"/miri-script/Cargo.toml \
+# We need a nightly toolchain, for `-Zroot-dir`.
+cargo +nightly build $CARGO_EXTRA_FLAGS --manifest-path "$ROOT_DIR"/miri-script/Cargo.toml \
+  -Zroot-dir="$ROOT_DIR" \
   -q --target-dir "$MIRI_SCRIPT_TARGET_DIR" $MESSAGE_FORMAT || \
   ( echo "Failed to build miri-script. Is the 'nightly' toolchain installed?"; exit 1 )
 # Instead of doing just `cargo run --manifest-path .. $@`, we invoke miri-script binary directly. Invoking `cargo run` goes through

miri

@@ -24,3 +24,4 @@ rustc_version = "0.4"
 dunce = "1.0.4"
 directories = "5"
 serde_json = "1"
+tempfile = "3.13.0"

miri-script/Cargo.lock

@@ -172,7 +172,8 @@ impl Command {
             Command::Install { flags } => Self::install(flags),
             Command::Build { flags } => Self::build(flags),
             Command::Check { flags } => Self::check(flags),
-            Command::Test { bless, flags, target } => Self::test(bless, flags, target),
+            Command::Test { bless, flags, target, coverage } =>
+                Self::test(bless, flags, target, coverage),
             Command::Run { dep, verbose, many_seeds, target, edition, flags } =>
                 Self::run(dep, verbose, many_seeds, target, edition, flags),
             Command::Doc { flags } => Self::doc(flags),
@@ -458,9 +459,20 @@ impl Command {
         Ok(())
     }
 
-    fn test(bless: bool, mut flags: Vec<String>, target: Option<String>) -> Result<()> {
+    fn test(
+        bless: bool,
+        mut flags: Vec<String>,
+        target: Option<String>,
+        coverage: bool,
+    ) -> Result<()> {
         let mut e = MiriEnv::new()?;
 
+        let coverage = coverage.then_some(crate::coverage::CoverageReport::new()?);
+
+        if let Some(report) = &coverage {
+            report.add_env_vars(&mut e)?;
+        }
+
         // Prepare a sysroot. (Also builds cargo-miri, which we need.)
         e.build_miri_sysroot(/* quiet */ false, target.as_deref())?;
 
@@ -479,6 +491,11 @@ impl Command {
         // Then test, and let caller control flags.
         // Only in root project as `cargo-miri` has no tests.
         e.test(".", &flags)?;
+
+        if let Some(coverage) = &coverage {
+            coverage.show_coverage_report(&e)?;
+        }
+
         Ok(())
     }