[src][klibc]: Fixing hardware errors triggered by byte-aligned access…

[Maihuanyi]

… in the rt_memset function;

拉取/合并请求描述：(PR description)

[

• 修复rt_memset函数字节对齐访问问题，在GCC不同的编译等级下会偶发触发字节对齐的硬件错误；
• 已在N32H474开发板验证，在GCC不同的优化等级都验证过了；
  ]

当前拉取/合并请求的状态 Intent for your PR

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我在这个拉取/合并请求中已经考虑了 As part of this pull request, I've considered the following:

• 已经仔细查看过代码改动的对比 Already check the difference between PR and old code
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• 对难懂代码均提供对应的注释 I've commented appropriately where code is tricky
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[github-actions]

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[github-actions]

📌 Code Review Assignment

🏷️ Tag: kernel

Reviewers: GorrayLi ReviewSun hamburger-os lianux-mm wdfk-prog xu18838022837

Changed Files (Click to expand)

• src/klibc/kstring.c

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📊 Current Review Status (Last Updated: 2026-02-26 09:06 CST)

• ⌛ GorrayLi Pending Review
• ⌛ ReviewSun Pending Review
• ⌛ hamburger-os Pending Review
• ⌛ lianux-mm Pending Review
• ⌛ wdfk-prog Pending Review
• ⌛ xu18838022837 Pending Review

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[Rbb666]

请给出测试用例以及测试截图谢谢

[Copilot]

Pull request overview

This PR aims to prevent hardware faults reportedly triggered by byte-wise access in rt_memset() by changing how the word-sized fill buffer is constructed.
本 PR 旨在通过调整 rt_memset() 中字填充 buffer 的构造方式，避免据称由按字节访问触发的硬件错误。

Changes:

• Replaced byte-wise writes into buffer with a shift+OR construction loop in rt_memset().
• 用“左移 + 或运算”的方式替代对 buffer 的逐字节写入。

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