【Hacker News搬运】GCC 14中静态分析的改进

hackernews

Title: Improvements to static analysis in GCC 14

GCC 14中静态分析的改进

Text:

Url: https://developers.redhat.com/articles/2024/04/03/improvements-static-analysis-gcc-14-compiler

该文章讨论了GCC 14编译器中-fanalyzer静态分析 pass的改进，该编译器将于2024年4月发布。-fanalyzer选项通过执行C源代码进行符号执行，以在编译时识别潜在问题。GCC 14的新功能包括使用-Wanalyzer-infinite-loop警告检测无限循环，使用基于文本的图表可视化缓冲区溢出，更好地跟踪C字符串操作以及改进污染分析。作者建议使用Compiler Explorer网站来测试GCC 14编译器的新功能。

Post by: dmalcolm

Comments:

quincepie: To me fanalyzer is one of GCC killer features over clang. It makes programming C much easier by explaining errors. The error messages also began to feel similar to Rust in terms of being developer friendly.

quincepie: 对我来说，fanalyzer是GCC的杀手级功能之一。它通过解释错误使编程C变得更加容易。在对开发人员友好方面，错误消息也开始感觉与Rust相似。

perihelions: 36 more comments in this other thread:<a href="https://news.ycombinator.com/item?id=39918278">https://news.ycombinator.com/item?id=39918278</a> ("GCC 14 Boasts Nice ASCII Art for Visualizing Buffer Overflows (phoronix.com)", 2 hours ago)

perihelions: 另一个线程中还有36条评论：<a href=“https:&#x2F；新闻.ycombinator.com&#x2F？项目？id=39918278”>https:&#x20F&#x2F；news.ycombinator.com&#x2F；项目id＝39918278</a>（“GCC 14承载用于可视化缓冲区溢出的漂亮ASCII艺术（phoronix.com）” ，2小时前）

Davidbrcz: I wish there was a better output format for the analysis, because this is hell for screen readers.

Davidbrcz: 我希望有一个更好的分析输出格式，因为这对屏幕阅读器来说是地狱。

1udfx9cf8azi0: <pre><code> if (nbytes < sizeof(*hwrpb))
return -1;

if (copy_to_user(buffer, hwrpb, nbytes) != 0)
    return -2;

</code></pre>
The fix that was done was:<pre><code> if (nbytes > sizeof(*hwrpb))
</code></pre>
But I think the correct fix is:<pre><code> if (copy_to_user(buffer, hwrpb, sizeof(*hwrpb)) != 0)
</code></pre>
It never makes sense to copy out of the hwrpb pointer any size other than sizeof(*hwrpb).

1udfx9cf8azi0: <pre><code>if（nbytes&lt；sizeof（*hwrpb））return-1；if（copy_to_user（buffer，hwrpb，nbytes）！=0)return-2；</code></pre>所做的修复是：<pre><code>if（nbytes&gt；sizeof（*hwrpb））</code></pre>但我认为正确的修复方法是：<pre><code>if（copy_to_user（buffer，hwrpb，sizeof（*hwrpb））！=0)</code></pre>从hwrpb指针中复制除sizeof（*hwrpb）以外的任何大小都没有意义。

noam_k: Very cool stuff!I haven't done much C development lately, so I'm curious how often strcpy and strcat are used. Last I checked they're almost as big no-nos as using goto. (Yes, I know goto is often preferred in kernel dev...) Can anyone share on how helpful the c-string analyses are to them?

noam_k: 非常酷的东西 我没有；最近没有做太多的C开发，所以我；我很好奇“strcpy”和“strcat”的使用频率。最后我检查了一下他们；re几乎和使用goto一样大。（是的，我知道goto在内核开发中通常是首选…）有人能分享一下c字符串分析对他们有多大帮助吗？