编译错误:multiple types in one declaration

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本文解决了C++编译过程中遇到的多重类型声明错误。通过分析错误信息和代码上下文，确定了问题是由重复定义BYTE引起，并给出了两种解决方案：一是修改头文件使用条件编译；二是使用#undef来解除定义。

昨天编译时报如下错误

/data/..../hnconv.h:6: error: multiple types in one declaration
/data..../hnconv.h:6: error: declaration does not declare anything

 

代码如下:


在网上查了些资料, 有两种可能性.

 

1. typedef语句后面没有加分号

2. 重复define BYTE

 

看头文件,排除1的可能性,针对2,有两种方法解决.

1. 在头文件中typedef语句前后加上ifdef开关

2. 在调用处加上undef BYTE

 

由于hnconv.h是底层库, 由外部团队提供, 因此采用第二种方式解决.

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