Rust: various unsafe traits/functions meant for gencode in public API

描述

fn main() {
    let ptr: &&u8 = flatbuffers::follow_cast_ref(&[1, 2, 3, 4, 5, 6, 7, 8], 0);
    println!("{}", **ptr);
}

贡献者指南

技术栈

rust

领域

backend

议题类型

bug

难度面向新贡献者的预计实现难度，1 表示很小改动，5 表示专家级工作。

4

预计时间有经验贡献者完成调查、实现、测试并准备 pull request 的粗略时间范围。

1-2 days

活动状态议题当前的可参与程度：新鲜、活跃、陈旧、阻塞或等待维护者输入。

active

清晰度议题是否清楚说明期望改动、验收标准和下一步。

mostly clear

前置要求

Rust programmingunderstanding of unsafe codeknowledge of flatbuffers internals

新手友好度1-100 的估计分数，表示该议题对首次贡献者的友好程度。

30

研究方向

Investigate the unsafe functions `follow cast ref` and related traits in the Rust flatbuffers source (likely in `rust/flatbuffers/src/lib.rs`). The issue demonstrates a segfault when calling `follow cast ref` on a byte slice. The problem is that the function assumes the referenced data is valid for the type `T`, but the input is not properly aligned or sized. Check how `follow cast ref` is implemented and whether it should be marked unsafe. Look at the discussion in issue #6627 for additional context and any proposed fixes.