在scanf中的倒置参数（） [英] Inverted arguments in scanf()

问题描述

我是（快速）写一些code和意外在倒参数scanf（）的：

 我的char [] =ABC1 \\ t的;
scanf函数（我，％S）;
 

与 GCC -Werror -Wall -Wextra 编译不抱怨这一位。显然，这code没有工作，但为什么不属于GCC告诉我，我倒的论点？不能把它检测到 I 不是一个格式字符串，或者第二个参数是不是一个商店能够类型？

修改结果
感谢您的见解是，看起来像我找到了答案，有一对 -Wformat 标志，使这个开捕（贴吧以下供参考）

解决方案

哈！我找到了。打与 -Wformat = 2 标志GCC接住了。

发布的信息为他人参考：

下面的标志，我发现名单>

-Wformat
检查调用printf和scanf等，以确保提供参数的适当指定的格式字符串类型...

我曾以为 -Wall 不得不 -Wformat 在里面，这确实如此，但对真正重要的组成部分我刚才发现：

-Wformat包含在-Wall。用于在格式检测的一些方面，选择-Wformat-2000年，-Wno格式-额外指定参数时，-Wno格式零长度，多个控制-Wformat-非字面，-Wformat的安全性，和-Wformat = 2都可用，但不包括在-Wall

I was (quickly) writing some code and accidently inverted the arguments in scanf():

char i[] = "ABC1\t";
scanf(i, "%s");

Compiling with gcc -Werror -Wall -Wextra doesn't complain about this one bit. Obviously, this code doesn't work, but why didn't gcc inform me that I inverted the arguments? Can't it detect that i is not a format string, or that the second argument was not a store-able type?

EDIT
Thanks for the insight all, Looks like I found the answer, there was a twist on the -Wformat flag that makes this "catchable" (posted it below for reference)

解决方案

Ha! I found it. Hitting gcc with the -Wformat=2 flag caught it.

Posting the info for reference of others:

Here's the list of flags I found

-Wformat Check calls to printf and scanf, etc., to make sure that the arguments supplied have types appropriate to the format string specified...

I had assumed -Wall had -Wformat in it, which it does, but the really important part about what I just found:

-Wformat is included in -Wall. For more control over some aspects of format checking, the options -Wformat-y2k, -Wno-format-extra-args, -Wno-format-zero-length, -Wformat-nonliteral, -Wformat-security, and -Wformat=2 are available, but are not included in -Wall.

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