/unsafe-check

Check a file for unsafe code issues and potential safety violations.

zhanghandong@zhanghandong

GitHub

From plugin

rust-skills

1.4k21 skills11 agents21 commands1 hook

Install

> /plugin marketplace add zhanghandong/rust-skills
> /plugin install rust-skills@rust-skills

How it fires

How this command gets triggered: by you, by Claude, or both.

Fires itselfClaude auto-loads it when your prompt matches the work.
You can call itInvoke it directly when you want it.
Slash command/unsafe-check

Context preview

What this command does when you run it.

Check a file for unsafe code issues and potential safety violations.

Command definition

unsafe-check.md

/unsafe-check

Check a file for unsafe code issues and potential safety violations.

Usage

/unsafe-check [file]

Parameters

`file` (optional): Path to the Rust file to check. If not provided, checks the current file or prompts for input.

Workflow

1. **Read the file** to identify all `unsafe` blocks and `unsafe fn` 2. **Load unsafe-checker skill** rules 3. **Check each unsafe block** against relevant rules:

SAFETY comment present? (safety-09)
Pointer validity verified? (ptr-*)
Panic safety considered? (safety-01)
FFI rules followed? (ffi-*)

4. **Report findings** with rule references and fix suggestions

Checks Performed

Safety Comments

Every `unsafe` block should have `// SAFETY:` comment
Comment should explain invariants, not just say "this is safe"

Pointer Operations

Null checks before dereference
Alignment verification
Bounds checking
No aliasing violations

FFI

Types have `#[repr(C)]`
Panics caught at boundary
String handling correct
Memory ownership clear

Send/Sync

Manual implementations are sound
No data races possible

Example Output

Checking: src/lib.rs

Found 3 unsafe blocks:

1. Line 42: unsafe { ptr.read() }
   - [WARN] Missing SAFETY comment (safety-09)
   - [WARN] No null check for ptr (ptr-01)
   Suggestion: Add SAFETY comment and verify ptr is non-null

2. Line 87: unsafe impl Send for MyType {}
   - [WARN] Missing Safety docs (safety-10)
   - [OK] Type analysis shows no !Send fields
   Suggestion: Add /// # Safety documentation

3. Line 123: extern "C" fn callback() { ... }
   - [WARN] No catch_unwind (ffi-04)
   Suggestion: Wrap body in std::panic::catch_unwind