util: Rewrite Arc based on std::sync::Arc

.github/.cspell/project-dictionary.txt

@@ -44,6 +44,7 @@ DESTDIR
 DEVEL
 dlsym
 DWCAS
+elems
 espup
 exynos
 FIQs
@@ -157,6 +158,7 @@ uapi
 uart
 umax
 umin
+unclonable
 unistd
 unparse
 usart

.github/workflows/ci.yml

@@ -519,6 +519,7 @@ jobs:
           persist-credentials: false
       - name: Install Rust
         run: rustup toolchain add nightly --no-self-update --component miri && rustup default nightly
+      - uses: taiki-e/install-action@cargo-hack
       # - run: sudo apt-get -o Acquire::Retries=10 -qq update && sudo apt-get -o Acquire::Retries=10 -o Dpkg::Use-Pty=0 install -y --no-install-recommends moreutils
       - run: echo "TARGET=--target=${{ matrix.target }}" >>"${GITHUB_ENV}"
         if: matrix.target != 'x86_64-unknown-linux-gnu'
@@ -544,6 +545,7 @@ jobs:
           persist-credentials: false
       - name: Install Rust
         run: rustup toolchain add nightly --no-self-update && rustup default nightly
+      - uses: taiki-e/install-action@cargo-hack
       # - run: sudo apt-get -o Acquire::Retries=10 -qq update && sudo apt-get -o Acquire::Retries=10 -o Dpkg::Use-Pty=0 install -y --no-install-recommends moreutils
       - run: |
           echo "ASAN_OPTIONS=detect_stack_use_after_return=1" >>"${GITHUB_ENV}"
@@ -578,6 +580,7 @@ jobs:
           persist-credentials: false
       - name: Install Rust
         run: rustup toolchain add nightly --no-self-update && rustup default nightly
+      - uses: taiki-e/install-action@cargo-hack
       # - run: sudo apt-get -o Acquire::Retries=10 -qq update && sudo apt-get -o Acquire::Retries=10 -o Dpkg::Use-Pty=0 install -y --no-install-recommends moreutils
       - uses: taiki-e/install-action@valgrind
       - run: tools/test.sh valgrind -vv

portable-atomic-util/build.rs

@@ -37,6 +37,10 @@ fn main() {
     if !version.probe(52, 2021, 3, 10) {
         println!("cargo:rustc-cfg=portable_atomic_no_unsafe_op_in_unsafe_fn");
     }
+    // https://github.com/rust-lang/rust/pull/84662 merged in Rust 1.56 (nightly-2021-08-02).
+    if !version.probe(56, 2021, 8, 1) {
+        println!("cargo:rustc-cfg=portable_atomic_no_core_unwind_safe");
+    }
 
     if version.nightly {
         // `cfg(sanitize = "..")` is not stabilized.