C 函数名称更改？

Question

我有以下 C 代码：

void test_func()
{
    __asm__ ("mov    [=10=]x2,%rax");
    __asm__ ("mov    [=10=]x6000dd,%rdi");
    __asm__ ("mov    [=10=]x0,%rsi");
    __asm__ ("syscall");
}
int main(int argc, char *argv[]) {
    test_func();
    return 0;
}

当我这样编译时 gcc mine.cxx -S -no-pie 我在汇编文件中得到以下内容：

.globl _Z9test_funcv

为什么我的函数名称会改变以及如何防止这种情况/预测它的新名称？

Answer 1

您正在将其编译为 C++ 代码，而不是 C。在 C++ 中 names are mangled to support things like function overloading and templates. Mangling rules depend on compiler but it usually begins with _Z, especially in compilers following Itanium C++ ABI

见What is name mangling, and how does it work?

您需要将代码编译为C。编译器通常根据扩展名来确定语言，而在GCC中cxx is one of the C++ extensions so just rename the file to *.c. You can also force the compiler to compile code as C regardless of the extension. The option to do that depends on compiler, for example in MSVC use /TC and in GCC use -x c

请注意，您应该 never put instructions in separate __asm__ statements 那样，因为允许编译器在它们之间放置任意指令

C 函数名称更改？

Name of C function changes?

c

symbols

elf

name-mangling