c - 解析问题与评论 ://causes errors while/* does not

Question

我正在处理一个大型项目并遇到此错误:error: expected expression before '/' token

这发生在尝试使用 //... 注释掉我的代码中的一行时。当我将其替换为 /* ... */

时错误消失了

据我所知，这两种评论格式都是合法的:

1 Except within a character constant, a string literal, or a comment, the characters /* introduce a comment. The contents of such a comment are examined only to identify multibyte characters and to find the characters */ that terminate it.83)

2 Except within a character constant, a string literal, or a comment, the characters // introduce a comment that includes all multibyte characters up to, but not including, the next new-line character. The contents of such a comment are examined only to identify multibyte characters and to find the terminating new-line character.

这是平台特定的问题吗？

编辑: 我的项目是用 gnu 编译器 和以下标志编译的:-ansi -fno-zero-initialized-in-bss -Wall。将 -ansi 替换为 -std=c99(或更新版本)可以解决问题。

Answer 1

单行注释//是C99引入的。如果您使用的是 GCC 或 Clang，请使用选项 -std=c99 或 -std=c11 编译您的程序。

n1256-前言 (p5):

Major changes from the previous edition include:
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— // comments
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