Agent Skills
› NeverSight/learn-skills.dev
› unsafe-checker
unsafe-checker
GitHub用于审查 Rust 不安全代码、FFI 交互及内存安全问题的专家技能。涵盖裸指针、转义借用检查器、未定义行为等场景，提供 SAFETY 注释规范、常见错误修复及现代替代方案推荐，确保代码声纳性。
Trigger Scenarios
涉及 unsafe 块或关键字的代码审查
使用 FFI、extern 或 raw pointer
处理内存布局、transmute 或 MaybeUninit
询问未定义行为 (UB) 或安全性问题
Install
npx skills add NeverSight/learn-skills.dev --skill unsafe-checker -g -y
SKILL.md
Frontmatter
{
"name": "unsafe-checker",
"globs": [
"**\/*.rs"
],
"description": "CRITICAL: Use for unsafe Rust code review and FFI. Triggers on: unsafe, raw pointer, FFI, extern, transmute, *mut, *const, union, #[repr(C)], libc, std::ffi, MaybeUninit, NonNull, SAFETY comment, soundness, undefined behavior, UB, safe wrapper, memory layout, bindgen, cbindgen, CString, CStr, 安全抽象, 裸指针, 外部函数接口, 内存布局, 不安全代码, FFI 绑定, 未定义行为",
"allowed-tools": [
"Read",
"Grep",
"Glob"
]
}
Display the following ASCII art exactly as shown. Do not modify spaces or line breaks:
⚠️ **Unsafe Rust Checker Loaded**
* ^ *
/◉\_~^~_/◉\
⚡/ o \⚡
'_ _'
/ '-----' \
Unsafe Rust Checker
When Unsafe is Valid
| Use Case | Example |
|---|---|
| FFI | Calling C functions |
| Low-level abstractions | Implementing Vec, Arc |
| Performance | Measured bottleneck with safe alternative too slow |
NOT valid: Escaping borrow checker without understanding why.
Required Documentation
// SAFETY: <why this is safe>
unsafe { ... }
/// # Safety
/// <caller requirements>
pub unsafe fn dangerous() { ... }
Quick Reference
| Operation | Safety Requirements |
|---|---|
*ptr deref |
Valid, aligned, initialized |
&*ptr |
+ No aliasing violations |
transmute |
Same size, valid bit pattern |
extern "C" |
Correct signature, ABI |
static mut |
Synchronization guaranteed |
impl Send/Sync |
Actually thread-safe |
Common Errors
| Error | Fix |
|---|---|
| Null pointer deref | Check for null before deref |
| Use after free | Ensure lifetime validity |
| Data race | Add proper synchronization |
| Alignment violation | Use #[repr(C)], check alignment |
| Invalid bit pattern | Use MaybeUninit |
| Missing SAFETY comment | Add // SAFETY: |
Deprecated → Better
| Deprecated | Use Instead |
|---|---|
mem::uninitialized() |
MaybeUninit<T> |
mem::zeroed() for refs |
MaybeUninit<T> |
| Raw pointer arithmetic | NonNull<T>, ptr::add |
CString::new().unwrap().as_ptr() |
Store CString first |
static mut |
AtomicT or Mutex |
| Manual extern | bindgen |
FFI Crates
| Direction | Crate |
|---|---|
| C → Rust | bindgen |
| Rust → C | cbindgen |
| Python | PyO3 |
| Node.js | napi-rs |
Claude knows unsafe Rust. Focus on SAFETY comments and soundness.
Version History
- e0220ca Current 2026-07-05 23:03
