Fix stacked borrows violations in epoch & skiplist, fix CI failures

.github/workflows/ci.yml

@@ -40,29 +40,29 @@ jobs:
       matrix:
         # macOS is tested on Cirrus CI due to GitHub-hosted macOS runners are slow.
         include:
-          - rust: '1.63'
+          - rust: '1.74'
             os: ubuntu-latest
-          - rust: '1.63'
-            os: ubuntu-22.04-arm # TODO: update to 24.04 when https://github.com/rust-lang/rust/issues/135867 solved
-          - rust: '1.63'
+          - rust: '1.74'
+            os: ubuntu-24.04-arm
+          - rust: '1.74'
             os: windows-latest
           - rust: stable
             os: ubuntu-latest
           - rust: stable
-            os: ubuntu-22.04-arm # TODO: update to 24.04 when https://github.com/rust-lang/rust/issues/135867 solved
+            os: ubuntu-24.04-arm
           - rust: stable
             os: windows-latest
           - rust: nightly
             os: ubuntu-latest
           - rust: nightly
-            os: ubuntu-22.04-arm # TODO: update to 24.04 when https://github.com/rust-lang/rust/issues/135867 solved
+            os: ubuntu-24.04-arm
           - rust: nightly
             os: windows-latest
           - rust: nightly
             os: ubuntu-latest
             target: i686-unknown-linux-gnu
           - rust: nightly
-            os: ubuntu-22.04-arm # TODO: update to 24.04 when https://github.com/rust-lang/rust/issues/135867 solved
+            os: ubuntu-24.04-arm
             target: armv7-unknown-linux-gnueabihf
           # Test 32-bit target that does not have AtomicU64/AtomicI64.
           - rust: nightly
@@ -193,6 +193,9 @@ jobs:
         group:
           - channel
           - others
+        miriflags:
+          - ''
+          - '-Zmiri-tree-borrows'
     runs-on: ubuntu-latest
     timeout-minutes: 120 # TODO
     steps:
@@ -203,6 +206,8 @@ jobs:
           component: miri
       - name: miri
         run: ci/miri.sh ${{ matrix.group }}
+        env:
+          MIRIFLAGS: ${{ matrix.miriflags }}
 
   # Run cargo-careful.
   careful:
@@ -228,8 +233,6 @@ jobs:
         uses: taiki-e/github-actions/install-rust@nightly
         with:
           component: rust-src
-      # https://github.com/google/sanitizers/issues/1716 / https://github.com/actions/runner-images/issues/9491
-      - run: sudo sysctl vm.mmap_rnd_bits=28
       - name: Run sanitizers
         run: ci/san.sh
 

Cargo.toml

@@ -6,7 +6,8 @@ name = "crossbeam"
 # - Run './tools/publish.sh crossbeam <version>'
 version = "0.8.4"
 edition = "2021"
-rust-version = "1.61"
+# NB: Sync with msrv badge and "Compatibility" section in README.md
+rust-version = "1.74"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/crossbeam-rs/crossbeam"
 homepage = "https://github.com/crossbeam-rs/crossbeam"
@@ -73,3 +74,4 @@ unreachable_pub = "warn"
 declare_interior_mutable_const = { level = "allow", priority = 1 } # https://github.com/rust-lang/rust-clippy/issues/7665
 incompatible_msrv = { level = "allow", priority = 1 } # buggy: doesn't consider cfg, https://github.com/rust-lang/rust-clippy/issues/12280, https://github.com/rust-lang/rust-clippy/issues/12257#issuecomment-2093667187
 lint_groups_priority = { level = "allow", priority = 1 } # https://github.com/rust-lang/rust-clippy/issues/12920
+manual_map = { level = "allow", priority = 1 }

README.md

@@ -8,7 +8,7 @@ https://github.com/crossbeam-rs/crossbeam#license)
 https://crates.io/crates/crossbeam)
 [![Documentation](https://docs.rs/crossbeam/badge.svg)](
 https://docs.rs/crossbeam)
-[![Rust 1.61+](https://img.shields.io/badge/rust-1.61+-lightgray.svg)](
+[![Rust 1.74+](https://img.shields.io/badge/rust-1.74+-lightgray.svg)](
 https://www.rust-lang.org)
 [![chat](https://img.shields.io/discord/569610676205781012.svg?logo=discord)](https://discord.com/invite/JXYwgWZ)
 
@@ -94,7 +94,7 @@ crossbeam = "0.8"
 
 Crossbeam supports stable Rust releases going back at least six months,
 and every time the minimum supported Rust version is increased, a new minor
-version is released. Currently, the minimum supported Rust version is 1.61.
+version is released. Currently, the minimum supported Rust version is 1.74.
 
 ## Contributing
 

ci/check-features.sh

@@ -8,9 +8,9 @@ cd "$(dirname "$0")"/..
 # * `--exclude benchmarks` - benchmarks doesn't published.
 if [[ "${RUST_VERSION}" == "msrv" ]]; then
     cargo hack build --all --feature-powerset --no-dev-deps --exclude crossbeam-utils --exclude benchmarks --rust-version
-    # atomic feature requires Rust 1.60.
+    # atomic feature requires Rust 1.74.
     cargo hack build -p crossbeam-utils --feature-powerset --no-dev-deps --rust-version --exclude-features atomic
-    cargo +1.60 hack build -p crossbeam-utils --feature-powerset --no-dev-deps
+    cargo +1.74 hack build -p crossbeam-utils --feature-powerset --no-dev-deps
 else
     cargo hack build --all --feature-powerset --no-dev-deps --exclude benchmarks
 fi

ci/miri.sh

@@ -26,18 +26,14 @@ case "${group}" in
     others)
         cargo miri test --all-features \
             -p crossbeam-queue \
-            -p crossbeam-utils 2>&1 | ts -i '%.s  '
-        # Use Tree Borrows instead of Stacked Borrows because epoch is not compatible with Stacked Borrows: https://github.com/crossbeam-rs/crossbeam/issues/545#issuecomment-1192785003
-        MIRIFLAGS="${MIRIFLAGS} -Zmiri-tree-borrows" \
-            cargo miri test --all-features \
             -p crossbeam-epoch \
+            -p crossbeam-utils \
             -p crossbeam-skiplist \
             -p crossbeam 2>&1 | ts -i '%.s  '
-        # Use Tree Borrows instead of Stacked Borrows because epoch is not compatible with Stacked Borrows: https://github.com/crossbeam-rs/crossbeam/issues/545#issuecomment-1192785003
         # -Zmiri-compare-exchange-weak-failure-rate=0.0 is needed because some sequential tests (e.g.,
         # doctest of Stealer::steal) incorrectly assume that sequential weak CAS will never fail.
         # -Zmiri-preemption-rate=0 is needed because this code technically has UB and Miri catches that.
-        MIRIFLAGS="${MIRIFLAGS} -Zmiri-tree-borrows -Zmiri-compare-exchange-weak-failure-rate=0.0 -Zmiri-preemption-rate=0" \
+        MIRIFLAGS="${MIRIFLAGS} -Zmiri-compare-exchange-weak-failure-rate=0.0 -Zmiri-preemption-rate=0" \
             cargo miri test --all-features \
             -p crossbeam-deque 2>&1 | ts -i '%.s  '
         ;;

crossbeam-channel/Cargo.toml

@@ -6,7 +6,8 @@ name = "crossbeam-channel"
 # - Run './tools/publish.sh crossbeam-channel <version>'
 version = "0.5.15"
 edition = "2021"
-rust-version = "1.60"
+# NB: Sync with msrv badge and "Compatibility" section in README.md
+rust-version = "1.74"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/crossbeam-rs/crossbeam"
 homepage = "https://github.com/crossbeam-rs/crossbeam/tree/master/crossbeam-channel"

crossbeam-channel/README.md

@@ -8,7 +8,7 @@ https://github.com/crossbeam-rs/crossbeam/tree/master/crossbeam-channel#license)
 https://crates.io/crates/crossbeam-channel)
 [![Documentation](https://docs.rs/crossbeam-channel/badge.svg)](
 https://docs.rs/crossbeam-channel)
-[![Rust 1.60+](https://img.shields.io/badge/rust-1.60+-lightgray.svg)](
+[![Rust 1.74+](https://img.shields.io/badge/rust-1.74+-lightgray.svg)](
 https://www.rust-lang.org)
 [![chat](https://img.shields.io/discord/569610676205781012.svg?logo=discord)](https://discord.com/invite/JXYwgWZ)
 
@@ -48,7 +48,7 @@ crossbeam-channel = "0.5"
 
 Crossbeam Channel supports stable Rust releases going back at least six months,
 and every time the minimum supported Rust version is increased, a new minor
-version is released. Currently, the minimum supported Rust version is 1.60.
+version is released. Currently, the minimum supported Rust version is 1.74.
 
 ## License
 

crossbeam-deque/Cargo.toml

@@ -6,7 +6,8 @@ name = "crossbeam-deque"
 # - Run './tools/publish.sh crossbeam-deque <version>'
 version = "0.8.6"
 edition = "2021"
-rust-version = "1.61"
+# NB: Sync with msrv badge and "Compatibility" section in README.md
+rust-version = "1.74"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/crossbeam-rs/crossbeam"
 homepage = "https://github.com/crossbeam-rs/crossbeam/tree/master/crossbeam-deque"

crossbeam-deque/README.md

@@ -8,7 +8,7 @@ https://github.com/crossbeam-rs/crossbeam/tree/master/crossbeam-deque#license)
 https://crates.io/crates/crossbeam-deque)
 [![Documentation](https://docs.rs/crossbeam-deque/badge.svg)](
 https://docs.rs/crossbeam-deque)
-[![Rust 1.61+](https://img.shields.io/badge/rust-1.61+-lightgray.svg)](
+[![Rust 1.74+](https://img.shields.io/badge/rust-1.74+-lightgray.svg)](
 https://www.rust-lang.org)
 [![chat](https://img.shields.io/discord/569610676205781012.svg?logo=discord)](https://discord.com/invite/JXYwgWZ)
 
@@ -28,7 +28,7 @@ crossbeam-deque = "0.8"
 
 Crossbeam Deque supports stable Rust releases going back at least six months,
 and every time the minimum supported Rust version is increased, a new minor
-version is released. Currently, the minimum supported Rust version is 1.61.
+version is released. Currently, the minimum supported Rust version is 1.74.
 
 ## License
 

crossbeam-deque/src/deque.rs

@@ -771,7 +771,7 @@ impl<T> Stealer<T> {
         }
 
         // Reserve capacity for the stolen batch.
-        let batch_size = cmp::min((len as usize + 1) / 2, limit);
+        let batch_size = cmp::min((len as usize).div_ceil(2), limit);
         dest.reserve(batch_size);
         let mut batch_size = batch_size as isize;
 
@@ -1623,7 +1623,7 @@ impl<T> Injector<T> {
             } else {
                 let len = (tail - head) >> SHIFT;
                 // Steal half of the available tasks.
-                advance = ((len + 1) / 2).min(limit);
+                advance = len.div_ceil(2).min(limit);
             }
         } else {
             // We can steal all tasks till the end of the block.
@@ -1820,7 +1820,7 @@ impl<T> Injector<T> {
             } else {
                 let len = (tail - head) >> SHIFT;
                 // Steal half of the available tasks.
-                advance = ((len + 1) / 2).min(limit);
+                advance = len.div_ceil(2).min(limit);
             }
         } else {
             // We can steal all tasks till the end of the block.

crossbeam-epoch/Cargo.toml

@@ -6,7 +6,8 @@ name = "crossbeam-epoch"
 # - Run './tools/publish.sh crossbeam-epoch <version>'
 version = "0.9.18"
 edition = "2021"
-rust-version = "1.61"
+# NB: Sync with msrv badge and "Compatibility" section in README.md
+rust-version = "1.74"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/crossbeam-rs/crossbeam"
 homepage = "https://github.com/crossbeam-rs/crossbeam/tree/master/crossbeam-epoch"

crossbeam-epoch/README.md

@@ -8,7 +8,7 @@ https://github.com/crossbeam-rs/crossbeam/tree/master/crossbeam-epoch#license)
 https://crates.io/crates/crossbeam-epoch)
 [![Documentation](https://docs.rs/crossbeam-epoch/badge.svg)](
 https://docs.rs/crossbeam-epoch)
-[![Rust 1.61+](https://img.shields.io/badge/rust-1.61+-lightgray.svg)](
+[![Rust 1.74+](https://img.shields.io/badge/rust-1.74+-lightgray.svg)](
 https://www.rust-lang.org)
 [![chat](https://img.shields.io/discord/569610676205781012.svg?logo=discord)](https://discord.com/invite/JXYwgWZ)
 
@@ -35,7 +35,7 @@ crossbeam-epoch = "0.9"
 
 Crossbeam Epoch supports stable Rust releases going back at least six months,
 and every time the minimum supported Rust version is increased, a new minor
-version is released. Currently, the minimum supported Rust version is 1.61.
+version is released. Currently, the minimum supported Rust version is 1.74.
 
 ## License