gcc命令-E参数
-E
Stop after the preprocessing stage; do not run the compiler proper. The output is in the form of preprocessed source code, which is sent to the standard output.
Input files that don’t require preprocessing are ignored.
-E
在预处理阶段后停止; 不要正确运行编译器。 输出采用预处理源代码的形式,发送到标准输出。
不需要预处理的输入文件将被忽略。