Error #include nested too deeply

转载：http://blog.csdn.net/ysdaniel/article/details/7043395

出现 Error #include nested too deeply 原因是：

头文件相互包含。

例如，一个工程中bsp.h 包含 LocDongle.h, LocDongle.h又包含bsp.h，

编译时就会报Error #include nested too deeply 。

 

解决办法：

1、将两个头文件共用的那一部分抽出来单独建一个头文件。

2、加预处理#ifndef.. #define...#endif

 

//bsp.h
#ifndef _BSP_H_
#define _BSP_H_
#include "LocDongle.h"
#endif

//LocDongle.h
#ifndef _LOCDONGLE_H_
#define _LOCDONGLE_H_
#include "bsp.h"
#endif

<span style="font-family: simsun; line-height: 23px; "></span><pre><div><span style="line-height: 18px; color: rgb(0, 128, 0); ">//</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">bsp.h</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">
</span><span style="line-height: 18px; color: rgb(0, 0, 0); ">#ifndef _BSP_H_</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">//</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">文件开始、第一行</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">
</span><span style="line-height: 18px; color: rgb(0, 0, 255); ">#define</span><span style="line-height: 18px; color: rgb(0, 0, 0); "> _BSP_H_</span><span style="line-height: 18px; color: rgb(0, 0, 0); ">
#include </span><span style="line-height: 18px; color: rgb(128, 0, 0); ">"</span><span style="line-height: 18px; color: rgb(128, 0, 0); ">LocDongle.h</span><span style="line-height: 18px; color: rgb(128, 0, 0); ">"</span><span style="line-height: 18px; color: rgb(0, 0, 0); ">
...</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">//</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">内容，所有的函数声明等等放这里</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">
</span><span style="line-height: 18px; color: rgb(0, 0, 255); ">#endif</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">//</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">文件末尾</span><span style="line-height: 18px; color: rgb(0, 0, 0); ">

</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">//</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">LocDongle.h</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">
</span><span style="line-height: 18px; color: rgb(0, 0, 0); ">#ifndef _LOCDONGLE_H_</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">//</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">文件开始、第一行</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">
</span><span style="line-height: 18px; color: rgb(0, 0, 255); ">#define</span><span style="line-height: 18px; color: rgb(0, 0, 0); "> _LOCDONGLE_H_</span><span style="line-height: 18px; color: rgb(0, 0, 0); ">
#include </span><span style="line-height: 18px; color: rgb(128, 0, 0); ">"</span><span style="line-height: 18px; color: rgb(128, 0, 0); ">bsp.h</span><span style="line-height: 18px; color: rgb(128, 0, 0); ">"</span><span style="line-height: 18px; color: rgb(0, 0, 0); ">
...</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">//</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">内容，所有的函数声明等等放这里</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">
</span><span style="line-height: 18px; color: rgb(0, 0, 255); ">#endif</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">//</span><span style="line-height: 18px; color: rgb(0, 128, 0); ">文件末尾</span></div><div><span style="line-height: 18px; color: rgb(0, 128, 0); ">
</span></div></pre><br>
<p></p>
<pre></pre>
<br>
<span style="font-family:simsun; font-size:14px; line-height:23px">头文件保护有用, 可以这样重复包含<br>
头文件包含其实就是在包含的位置展开它而已,<br>
你如果a.h包含了b.h<br>
b.h又包含了a.h<br>
如果你使用了#ifndef.. #define...#endif的话<br>
你在一个.c文件中包含a.h那么它里面包含的b.h中包含的a.h将不会重复包含。</span><br>
<p></p>
<p><span style="font-family:simsun; font-size:14px; line-height:23px"><span style="font-family:simsun; font-size:14px; line-height:23px"><span style="font-family:simsun; font-size:14px; line-height:23px"><span style="font-family:simsun; font-size:14px; line-height:23px">头文件的嵌套一定要防止不断的包含，处于一个无限的循环！</span><br>
</span></span></span></p>