c++ - UBSan 和 Asan 在 GCC 4.9.2 中的使用

Question

我已经使用 -fsanitize=undefined 选项编译了我的应用程序。我现在如何测试我的应用程序是否存在未定义的行为？

另外，我该如何进行牙山检查？我用 -fsanitize=address 编译了我的程序，它崩溃了，输出如下:

==4563==Sanitizer CHECK failed: ../../../../src/libsanitizer/asan/asan_malloc_linux.cc:85 ((allocated < kCallocPoolSize)) != (0) (0, 0)

我在 Ubuntu 15.04 上安装了 GCC 4.9.2。

Answer 1

与静态分析检查不同，此检查将在运行时完成，如以下博客条目所述:GCC Undefined Behavior Sanitizer – ubsan .当它检测到未定义的行为时，它会输出一个运行时错误:

In order to check your program with ubsan, compile and link theprogram with -fsanitize=undefined option. Such instrumented binarieshave to be executed; if ubsan detects any problem, it outputs a“runtime error:” message, and in most cases continues executing theprogram. There is a possibility of making these diagnostic messagesabort — just use the option -fno-sanitize-recover.

我们可以从那里看到一个例子:

int main() {
    int i = 23;
    i <<= 32; 
}

当使用 -fsanitize=undefined 运行时将输出 ( see it live ):

runtime error: shift exponent 32 is too large for 32-bit type 'int'

GCC 在他们的 Options for Debugging Your Program or GCC section 中记录了这个选项它说:

Enable UndefinedBehaviorSanitizer, a fast undefined behavior detector.Various computations are instrumented to detect undefined behavior atruntime.

asan issue this address-sanitizer document给你一个例子和预期的结果。也许你的情况与this gcc bug有关.