> For the complete documentation index, see [llms.txt](https://chenxiaowei.gitbook.io/cmake-cookbook/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://chenxiaowei.gitbook.io/cmake-cookbook/2.0-chinese.md).

# 第2章 检测环境

本章的主要内容有：

* 检测操作系统
* 处理与平台相关的源码
* 处理与编译器相关的源码
* 检测处理器体系结构
* 检测处理器指令集
* 为Eigen库使能向量化

尽管CMake跨平台，但有时源代码并不是完全可移植(例如：当使用依赖于供应商的扩展时)，我们努力使源代码能够跨平台、操作系统和编译器。这个过程中会发现，有必要根据平台不同的方式配置和/或构建代码。这对于历史代码或交叉编译尤其重要，我们将在第13章中讨论这个主题。了解处理器指令集也有助于优化特定目标平台的性能。本章会介绍，检测环境的方法，并给出建议。


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://chenxiaowei.gitbook.io/cmake-cookbook/2.0-chinese.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.