been writing rust for like ten minutes and i'm already dealing with this shit

Bumps [vendor/bdwgc](https://github.com/bdwgc/bdwgc) from `5c70f7c` to
`8202876`.
<details>
<summary>Commits</summary>
<ul>
<li><a
href="82028767b4"><code>8202876</code></a>
Move free lists initialization code out of GC_init_thread_local</li>
<li><a
href="58792803b6"><code>5879280</code></a>
Use compiler TLS for msys2/mingw gcc-4.9 and clang-8 (or later)</li>
<li><a
href="593710f55f"><code>593710f</code></a>
Use compiler TLS on Cygwin if clang-8 or later</li>
<li><a
href="933ca901fc"><code>933ca90</code></a>
GH Actions: Test with -D DARWIN_PARSE_STACK on macOS/arm64</li>
<li><a
href="79f5fa8741"><code>79f5fa8</code></a>
Support threads bounds detection by stack walking on Darwin/arm64</li>
<li><a
href="f9188d7798"><code>f9188d7</code></a>
Replace DARWIN_DONT_PARSE_STACK to opposite DARWIN_PARSE_STACK
macro</li>
<li><a
href="ec43144ad4"><code>ec43144</code></a>
Move define DARWIN_DONT_PARSE_STACK from configure to gcconfig.h for
XLC</li>
<li><a
href="49045ad244"><code>49045ad</code></a>
Remove unneeded non-empty ASM_CPP_OPTIONS for Darwin XLC</li>
<li><a
href="b73696ff75"><code>b73696f</code></a>
Use word type for address values in Darwin GC_FindTopOfStack</li>
<li><a
href="89256b2fae"><code>89256b2</code></a>
Remove dead code in GC_FindTopOfStack for Darwin/arm</li>
<li>Additional commits viewable in <a
href="5c70f7cac7...82028767b4">compare
view</a></li>
</ul>
</details>
<br />


Dependabot will resolve any conflicts with this PR as long as you don't
alter it yourself. You can also trigger a rebase manually by commenting
`@dependabot rebase`.

[//]: # (dependabot-automerge-start)
[//]: # (dependabot-automerge-end)

---

<details>
<summary>Dependabot commands and options</summary>
<br />

You can trigger Dependabot actions by commenting on this PR:
- `@dependabot rebase` will rebase this PR
- `@dependabot recreate` will recreate this PR, overwriting any edits
that have been made to it
- `@dependabot show <dependency name> ignore conditions` will show all
of the ignore conditions of the specified dependency
- `@dependabot ignore this major version` will close this PR and stop
Dependabot creating any more for this major version (unless you reopen
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Dependabot creating any more for this minor version (unless you reopen
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- `@dependabot ignore this dependency` will close this PR and stop
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</details>

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.cspell.json

@@ -1,11 +0,0 @@
-{
-  "words": [
-    "dealloc",
-    "finalizer",
-    "gcollect",
-    "libc",
-    "realloc",
-    "repr",
-    "stackbottom"
-  ]
-}

.envrc

@@ -0,0 +1 @@
+use flake

.github/mergify.yml

@@ -1,11 +0,0 @@
-pull_request_rules:
-  - name: dependabot
-    conditions:
-      - author=dependabot[bot]
-    actions:
-      queue:
-        name: default
-        method: squash
-queue_rules:
-  - name: default
-    conditions: []

.github/workflows/dependabot.yaml

@@ -0,0 +1,13 @@
+name: dependabot
+on: pull_request
+permissions:
+  contents: write
+  pull-requests: write
+jobs:
+  merge:
+    runs-on: ubuntu-latest
+    if: github.actor == 'dependabot[bot]'
+    steps:
+      - run: gh pr merge --auto --squash ${{ github.event.pull_request.html_url }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/lint.yaml

@@ -8,27 +8,25 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v6
         with:
           submodules: true
-      - uses: Swatinem/rust-cache@v2
+      - uses: swatinem/rust-cache@v2
       - run: cargo clippy -- -D warnings
   format:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v6
       - run: cargo fmt -- --check
   spell-check:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v6
       - uses: streetsidesoftware/cspell-action@main
         with:
           files: "**/*.{md,rs}"
   readme:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
-      - uses: lycheeverse/lychee-action@v1
-        with:
-          fail: true
+      - uses: actions/checkout@v6
+      - uses: lycheeverse/lychee-action@v2

.github/workflows/release.yaml

@@ -0,0 +1,29 @@
+name: release
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+concurrency:
+  group: release-${{ github.ref }}
+  cancel-in-progress: ${{ github.ref != 'refs/heads/main' }}
+jobs:
+  release:
+    permissions:
+      id-token: write
+    runs-on: ubuntu-latest
+    environment: ${{ github.ref == 'refs/heads/main' && 'release' || '' }}
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          submodules: true
+      - uses: swatinem/rust-cache@v2
+      - run: cargo install cargo-workspaces
+      - uses: rust-lang/crates-io-auth-action@v1
+        id: auth
+        if: github.ref == 'refs/heads/main'
+      - run: >
+          cargo workspaces publish -y --from-git --no-verify
+          ${{ github.ref != 'refs/heads/main' && '--dry-run' || '' }}
+        env:
+          CARGO_REGISTRY_TOKEN: ${{ steps.auth.outputs.token }}

.github/workflows/test.yaml

@@ -8,34 +8,32 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v6
         with:
           submodules: true
-      - uses: Swatinem/rust-cache@v2
+      - uses: swatinem/rust-cache@v2
       - run: cargo build
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v6
         with:
           submodules: true
-      - uses: Swatinem/rust-cache@v2
+      - uses: swatinem/rust-cache@v2
       - run: cargo test
   examples:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v6
         with:
           submodules: true
-      - uses: Swatinem/rust-cache@v2
-      - run: |
-          cd examples
-          ./test.sh
+      - uses: swatinem/rust-cache@v2
+      - run: tools/example_test.sh
   cmake:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v6
         with:
           submodules: true
-      - uses: Swatinem/rust-cache@v2
+      - uses: swatinem/rust-cache@v2
       - run: cargo build --no-default-features --features cmake

.gitignore

@@ -1,2 +1,3 @@
-*.lock
+.cargo_cache
 target
+.direnv

.gitmodules

@@ -1,6 +1,6 @@
 [submodule "vendor/bdwgc"]
 	path = vendor/bdwgc
-	url = https://github.com/ivmai/bdwgc
+	url = https://github.com/bdwgc/bdwgc
 [submodule "vendor/libatomic_ops"]
 	path = vendor/libatomic_ops
-	url = https://github.com/ivmai/libatomic_ops
+	url = https://github.com/bdwgc/libatomic_ops

Cargo.lock

@@ -0,0 +1,86 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "autotools"
+version = "0.2.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ef941527c41b0fc0dd48511a8154cd5fc7e29200a0ff8b7203c5d777dbc795cf"
+dependencies = [
+ "cc",
+]
+
+[[package]]
+name = "bdwgc-alloc"
+version = "0.6.13"
+dependencies = [
+ "autotools",
+ "cmake",
+ "libc",
+]
+
+[[package]]
+name = "cc"
+version = "1.2.49"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "90583009037521a116abf44494efecd645ba48b6622457080f080b85544e2215"
+dependencies = [
+ "find-msvc-tools",
+ "shlex",
+]
+
+[[package]]
+name = "cmake"
+version = "0.1.58"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c0f78a02292a74a88ac736019ab962ece0bc380e3f977bf72e376c5d78ff0678"
+dependencies = [
+ "cc",
+]
+
+[[package]]
+name = "dynamic_threads"
+version = "0.1.0"
+dependencies = [
+ "bdwgc-alloc",
+]
+
+[[package]]
+name = "find-msvc-tools"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3a3076410a55c90011c298b04d0cfa770b00fa04e1e3c97d3f6c9de105a03844"
+
+[[package]]
+name = "free_by_borrow"
+version = "0.1.0"
+dependencies = [
+ "bdwgc-alloc",
+]
+
+[[package]]
+name = "free_by_gc"
+version = "0.1.0"
+dependencies = [
+ "bdwgc-alloc",
+]
+
+[[package]]
+name = "libc"
+version = "0.2.186"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68ab91017fe16c622486840e4c83c9a37afeff978bd239b5293d61ece587de66"
+
+[[package]]
+name = "shlex"
+version = "1.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
+
+[[package]]
+name = "static_threads"
+version = "0.1.0"
+dependencies = [
+ "bdwgc-alloc",
+]

Cargo.toml

@@ -1,22 +1,29 @@
 [package]
 name = "bdwgc-alloc"
+version = "0.6.13"
+edition = "2024"
 description = "impl GlobalAlloc for bdwgc"
-version = "0.6.6"
-authors = [
-  "swgillespie <sean.william.g@gmail.com>",
-  "Yota Toyama <raviqqe@gmail.com>",
-]
 repository = "https://github.com/raviqqe/bdwgc-alloc"
-edition = "2021"
 license = "MIT"
-build = "build.rs"
+categories = ["api-bindings", "memory-management", "no-std", "no-std::no-alloc"]
+
+[workspace]
+resolver = "3"
+members = ["examples/*"]
+
+[dependencies]
+libc = "0.2.186"
+
+[build-dependencies]
+autotools = { version = "0.2.7", optional = true }
+cmake = { version = "0.1.58", optional = true }
 
 [features]
 default = ["autotools"]
 
-[dependencies]
-libc = "0.2"
-
-[build-dependencies]
-autotools = { version = "0.2", optional = true }
-cmake = { version = "0.1", optional = true }
+[lints.clippy]
+alloc_instead_of_core = "deny"
+dbg_macro = "deny"
+missing_const_for_fn = "deny"
+std_instead_of_alloc = "deny"
+std_instead_of_core = "deny"

README.md

@@ -1,8 +1,8 @@
-# bdwgc-alloc
+# bdwgc-rust
 
-[![GitHub Action](https://img.shields.io/github/actions/workflow/status/raviqqe/bdwgc-alloc/test.yaml?branch=main&style=flat-square)](https://github.com/raviqqe/bdwgc-alloc/actions)
+[![GitHub Action](https://img.shields.io/github/actions/workflow/status/bdwgc/bdwgc-rust/test.yaml?branch=main&style=flat-square)](https://github.com/bdwgc/bdwgc-rust/actions)
 [![Crate](https://img.shields.io/crates/v/bdwgc-alloc.svg?style=flat-square)](https://crates.io/crates/bdwgc-alloc)
-[![License](https://img.shields.io/github/license/raviqqe/bdwgc-alloc.svg?style=flat-square)](LICENSE)
+[![License](https://img.shields.io/github/license/bdwgc/bdwgc-rust.svg?style=flat-square)](LICENSE)
 
 [`GlobalAlloc`](https://doc.rust-lang.org/std/alloc/trait.GlobalAlloc.html) implementation for [`bdwgc`][bdwgc], the conservative garbage collector.
 
@@ -22,4 +22,4 @@ cargo build --no-default-features --features cmake
 
 [MIT](LICENSE)
 
-[bdwgc]: https://github.com/ivmai/bdwgc
+[bdwgc]: https://github.com/bdwgc/bdwgc

build.rs

@@ -6,7 +6,7 @@ fn main() {
     for dir in &[LIB_ATOMIC_OPS_DIR, LIB_GC_DIR] {
         std::process::Command::new("sh")
             .arg("-c")
-            .arg(format!("cd {} && ./autogen.sh", dir))
+            .arg(format!("cd {dir} && ./autogen.sh"))
             .output()
             .unwrap();
     }
@@ -17,12 +17,13 @@ fn main() {
 
     println!(
         "cargo:rustc-link-search=native={}",
-        dst.join("lib").display()
+        dst.join("lib64").display()
     );
     println!("cargo:rustc-link-lib=static=atomic_ops");
 
     let dst = autotools::Config::new(LIB_GC_DIR)
         .cflag(format!(
+            // spell-checker: disable-next-line
             "-I{} -L/lib/x86_64-linux-gnu -lpthread -fPIC",
             dst.join("include").display()
         ))
@@ -30,14 +31,14 @@ fn main() {
 
     println!(
         "cargo:rustc-link-search=native={}",
-        dst.join("lib").display()
+        dst.join("lib64").display()
     );
     println!("cargo:rustc-link-lib=static=gc");
 
     for dir in &[LIB_ATOMIC_OPS_DIR, LIB_GC_DIR] {
         std::process::Command::new("sh")
             .arg("-c")
-            .arg(format!("cd {} && git clean -dfx", dir))
+            .arg(format!("cd {dir} && git clean -dfx"))
             .output()
             .unwrap();
     }
@@ -58,13 +59,13 @@ fn main() {
 
     let dst = Config::new(LIB_GC_DIR)
         .profile("Release")
-        .define("BUILD_SHARED_LIBS", "FALSE")
+        .define("GC_BUILD_SHARED_LIBS", "FALSE")
         .cflag(format!("-I{}", libatomic_include_path))
         .build();
 
     println!(
         "cargo:rustc-link-search=native={}",
-        dst.join("lib").display()
+        dst.join("lib64").display()
     );
     println!("cargo:rustc-link-lib=static=gc");
 }

cspell.json

@@ -0,0 +1,21 @@
+{
+  "words": [
+    "autogen",
+    "autotools",
+    "bdwgc",
+    "canonicalize",
+    "cflag",
+    "clippy",
+    "dealloc",
+    "finalizer",
+    "gcollect",
+    "libatomic",
+    "libc",
+    "realloc",
+    "repr",
+    "rustc",
+    "stackbottom",
+    "swatinem",
+    "unregisters"
+  ]
+}

examples/Cargo.toml

@@ -1,7 +0,0 @@
-[workspace]
-members = [
-  "dynamic_threads",
-  "free_by_borrow",
-  "free_by_gc",
-  "static_threads",
-]

examples/dynamic_threads/Cargo.toml

@@ -1,8 +1,7 @@
 [package]
 name = "dynamic_threads"
 version = "0.1.0"
-authors = ["Yota Toyama <raviqqe@gmail.com>"]
-edition = "2018"
+edition = "2024"
 publish = false
 
 [dependencies]

examples/dynamic_threads/src/main.rs

@@ -1,5 +1,3 @@
-extern crate bdwgc_alloc;
-
 use bdwgc_alloc::Allocator;
 use std::alloc::Layout;
 
@@ -14,7 +12,7 @@ fn main() {
             unsafe { Allocator::register_current_thread().unwrap() }
 
             for _ in 0..100 {
-                unsafe { std::alloc::alloc(Layout::from_size_align(2 ^ 8, 8).unwrap()) };
+                let _ = unsafe { std::alloc::alloc(Layout::from_size_align(2 ^ 8, 8).unwrap()) };
             }
 
             unsafe { Allocator::unregister_current_thread() }

examples/free_by_borrow/Cargo.toml

@@ -1,8 +1,7 @@
 [package]
 name = "free_by_borrow"
 version = "0.1.0"
-authors = ["Yota Toyama <raviqqe@gmail.com>"]
-edition = "2018"
+edition = "2024"
 publish = false
 
 [dependencies]

examples/free_by_borrow/src/main.rs

@@ -1,5 +1,3 @@
-extern crate bdwgc_alloc;
-
 use bdwgc_alloc::Allocator;
 
 #[global_allocator]

examples/free_by_gc/Cargo.toml

@@ -1,8 +1,7 @@
 [package]
 name = "free_by_gc"
 version = "0.1.0"
-authors = ["Yota Toyama <raviqqe@gmail.com>"]
-edition = "2018"
+edition = "2024"
 publish = false
 
 [dependencies]

examples/free_by_gc/src/main.rs

@@ -1,5 +1,3 @@
-extern crate bdwgc_alloc;
-
 use bdwgc_alloc::Allocator;
 use std::alloc::Layout;
 
@@ -10,6 +8,6 @@ fn main() {
     unsafe { Allocator::initialize() }
 
     loop {
-        unsafe { std::alloc::alloc(Layout::from_size_align(2 ^ 8, 8).unwrap()) };
+        let _ = unsafe { std::alloc::alloc(Layout::from_size_align(2 ^ 8, 8).unwrap()) };
     }
 }

examples/static_threads/Cargo.toml

@@ -1,8 +1,7 @@
 [package]
 name = "static_threads"
 version = "0.1.0"
-authors = ["Yota Toyama <raviqqe@gmail.com>"]
-edition = "2018"
+edition = "2024"
 publish = false
 
 [dependencies]

examples/static_threads/src/main.rs

@@ -1,5 +1,3 @@
-extern crate bdwgc_alloc;
-
 use bdwgc_alloc::Allocator;
 use std::alloc::Layout;
 
@@ -13,7 +11,7 @@ fn main() {
         unsafe { Allocator::register_current_thread().unwrap() }
 
         loop {
-            unsafe { std::alloc::alloc(Layout::from_size_align(2 ^ 8, 8).unwrap()) };
+            let _ = unsafe { std::alloc::alloc(Layout::from_size_align(2 ^ 8, 8).unwrap()) };
         }
     });
 

examples/test.sh

@@ -1,13 +0,0 @@
-#!/bin/sh
-
-set -ex
-
-cargo build
-
-for cargo_file in */Cargo.toml
-do
-	target/debug/$(dirname $cargo_file) &
-	pid=$!
-	sleep 10
-	kill $pid
-done

flake.lock

@@ -0,0 +1,66 @@
+{
+  "nodes": {
+    "fenix": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "rust-analyzer-src": "rust-analyzer-src"
+      },
+      "locked": {
+        "lastModified": 1779185128,
+        "narHash": "sha256-Kl2bkmwZJD3n2KWDxuIlturZ7emqRK+anpD1LmDwpmY=",
+        "owner": "nix-community",
+        "repo": "fenix",
+        "rev": "b7bd9323fe26a3b4f4bddbb2c2a1dacabced2f88",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-community",
+        "repo": "fenix",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1778869304,
+        "narHash": "sha256-30sZNZoA1cqF5JNO9fVX+wgiQYjB7HJqqJ4ztCDeBZE=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "d233902339c02a9c334e7e593de68855ad26c4cb",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "fenix": "fenix",
+        "nixpkgs": "nixpkgs"
+      }
+    },
+    "rust-analyzer-src": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1779074864,
+        "narHash": "sha256-0M3WqsWmtXmv9Ev/vnFfCHosWvISDwiuuhQ104UO3CI=",
+        "owner": "rust-lang",
+        "repo": "rust-analyzer",
+        "rev": "cdfe408d4b436e806ff525cb3e67588a6a009ed1",
+        "type": "github"
+      },
+      "original": {
+        "owner": "rust-lang",
+        "ref": "nightly",
+        "repo": "rust-analyzer",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,54 @@
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    fenix = {
+      url = "github:nix-community/fenix";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+  };
+
+  outputs = { self, nixpkgs, fenix, ... }:
+  let
+    supportedSystems = [
+      "aarch64-darwin" "aarch64-linux"
+      "x86_64-darwin" "x86_64-linux"
+    ];
+
+    each-system = f: nixpkgs.lib.genAttrs supportedSystems (system: f rec {
+      pkgs = import nixpkgs {
+        inherit system overlays;
+      };
+      inherit (pkgs) lib;
+      inherit system;
+    });
+
+    overlays = [
+      fenix.overlays.default
+    ];
+
+  in {
+    _pkgs = each-system ({ pkgs, ... }: pkgs);
+
+    devShells = each-system ({ pkgs, lib, ... }: {
+      default = pkgs.mkShell {
+        packages = [
+          pkgs.pkg-config
+          (pkgs.fenix.complete.withComponents [
+            "cargo" "clippy" "rust-src" "rustc" "rustfmt"
+          ])
+          pkgs.rust-analyzer-nightly
+          pkgs.cmake
+        ];
+      };
+    });
+  };
+
+  nixConfig = {
+    extra-substituters = [
+      "https://fenix.cachix.org"
+    ];
+    extra-trusted-public-keys = [
+      "fenix.cachix.org-1:ecJhr+RdYEdcVgUkjruiYhjbBloIEGov7bos90cZi0Q="
+    ];
+  };
+}

rust-toolchain

@@ -1 +0,0 @@
-stable

rust-toolchain.toml

@@ -0,0 +1,3 @@
+[toolchain]
+channel = "stable"
+components = ["clippy", "rustfmt", "rust-analyzer", "rust-src"]

src/error.rs

@@ -1,4 +1,4 @@
-use std::{
+use core::{
     error,
     fmt::{self, Display, Formatter},
 };
@@ -9,7 +9,7 @@ pub struct Error {
 }
 
 impl Error {
-    pub fn new(description: &'static str) -> Error {
+    pub const fn new(description: &'static str) -> Error {
         Error { description }
     }
 }

src/lib.rs

@@ -1,10 +1,9 @@
 #![doc = include_str!("../README.md")]
-
-extern crate alloc;
+#![no_std]
 
 mod error;
 
-use alloc::alloc::{GlobalAlloc, Layout};
+use core::alloc::{GlobalAlloc, Layout};
 use core::ptr::null;
 use libc::{c_int, c_void, size_t};
 
@@ -17,7 +16,7 @@ struct GcStackBase {
 }
 
 #[link(name = "gc", kind = "static")]
-extern "C" {
+unsafe extern "C" {
     fn GC_allow_register_threads();
     fn GC_alloc_lock();
     fn GC_alloc_unlock();
@@ -42,67 +41,102 @@ extern "C" {
 pub struct Allocator;
 
 impl Allocator {
+    /// Locks a collector.
     pub fn lock() {
         unsafe { GC_alloc_lock() }
     }
 
+    /// Unlocks a collector.
     pub fn unlock() {
         unsafe { GC_alloc_unlock() }
     }
 
+    /// Initializes a collector.
+    ///
+    /// # Safety
+    ///
+    /// This function must be called in a main thread.
     pub unsafe fn initialize() {
-        GC_init();
-        GC_allow_register_threads();
+        unsafe {
+            GC_init();
+            GC_allow_register_threads();
+        }
     }
 
+    /// Registers a current thread to a collector.
+    ///
+    /// # Safety
+    ///
+    /// This function must not be called in a main thread.
     pub unsafe fn register_current_thread() -> Result<(), error::Error> {
         let mut base = GcStackBase { mem_base: null() };
 
-        if GC_get_stack_base(&mut base) != GC_SUCCESS {
+        if unsafe { GC_get_stack_base(&mut base) } != GC_SUCCESS {
             return Err(error::Error::new("failed to get stack base"));
-        } else if GC_register_my_thread(&base) != GC_SUCCESS {
+        } else if unsafe { GC_register_my_thread(&base) } != GC_SUCCESS {
             return Err(error::Error::new("failed to register a thread for GC"));
         }
 
         Ok(())
     }
 
+    /// Sets a bottom of a stack.
+    ///
+    /// You do not have to call this function in most cases.
+    /// A collector detects the bottom on initialization automatically.
+    ///
+    /// # Safety
+    ///
+    /// The bottom address must be valid.
     pub unsafe fn set_stack_bottom(bottom: *const u8) {
-        GC_set_stackbottom(
-            null(),
-            &GcStackBase {
-                mem_base: bottom as *const libc::c_void,
-            },
-        )
+        unsafe {
+            GC_set_stackbottom(
+                null(),
+                &GcStackBase {
+                    mem_base: bottom as *const libc::c_void,
+                },
+            )
+        }
     }
 
+    /// Unregisters a current thread from a collector.
+    ///
+    /// # Safety
+    ///
+    /// The thread must be registered already.
     pub unsafe fn unregister_current_thread() {
-        GC_unregister_my_thread()
+        unsafe { GC_unregister_my_thread() }
     }
 
+    /// Runs a garbage collection forcibly.
     pub fn force_collect() {
         unsafe { GC_gcollect() }
     }
 
+    /// Registers a finalizer of an object.
+    ///
+    /// # Safety
+    ///
+    /// The given finalizer must not be null and handle pointers properly.
     pub unsafe fn register_finalizer(
         ptr: *const c_void,
         finalizer: extern "C" fn(*mut c_void, *mut c_void),
         client_data: *const c_void,
     ) {
-        GC_register_finalizer(ptr, finalizer, client_data, null(), null());
+        unsafe { GC_register_finalizer(ptr, finalizer, client_data, null(), null()) };
     }
 }
 
 unsafe impl GlobalAlloc for Allocator {
     unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
-        GC_malloc(layout.size()) as *mut u8
+        (unsafe { GC_malloc(layout.size()) }) as *mut u8
     }
 
     unsafe fn dealloc(&self, ptr: *mut u8, _layout: Layout) {
-        GC_free(ptr as *mut c_void)
+        unsafe { GC_free(ptr as *mut c_void) }
     }
 
     unsafe fn realloc(&self, ptr: *mut u8, _layout: Layout, size: usize) -> *mut u8 {
-        GC_realloc(ptr as *mut c_void, size) as *mut u8
+        (unsafe { GC_realloc(ptr as *mut c_void, size) }) as *mut u8
     }
 }

tools/example_test.sh

@@ -0,0 +1,20 @@
+#!/bin/sh
+
+set -ex
+
+duration=20
+
+cd $(dirname $0)/..
+
+for directory in $(ls examples); do
+  (
+    cd examples/$directory
+
+    cargo build
+    cargo run &
+
+    pid=$!
+    sleep $duration
+    kill $pid
+  )
+done