问题描述
我在 gcc 中编译一些可移植代码时遇到了这个问题.基本上这个奇怪的代码在 Visual Studio 中编译，这真的让我大吃一惊:
I ran into this while compiling some portable code in gcc. Basically this strange code compiles in Visual studio which really just blows my mind:
class Zebra {int x;};
Zebra goo() {Zebra z; return z;}
void foo(Zebra &x)
{
Zebra y;
x = y;
foo(goo());
}
Visual Studio 让这个飞起来.gcc 会将此作为编译错误捕获.有趣的是，如果你将 Zebra 类型定义为 int，VC++ 会报错.相当矛盾的行为.想法?
Visual studio lets this one fly. gcc will catch this as a compile error. Interestingly, If you typedef Zebra to int, VC++ will complain. Quite contradictory behavior. Thoughts?
推荐答案
这是 Visual Studio 的旧扩展，我可以在 Microsoft 网站上找到的唯一参考是这个错误报告:临时对象可以绑定到非常量引用，它有以下示例代码:
This is old extension to Visual Studio, the only reference I could find on the Microsoft site was this bug report: Temporary Objects Can be Bound to Non-Const References, which has the following example code:
struct A {};
A f1();
void f2(A&);
int main()
{
f2(f1()); // This line SHALL trigger an error, but it can be compiled without any errors or warnings.
}
回复说明之一:
有一个 4 级警告(如果您将/W4 传递给编译器，则启用 4 级警告)
There is a level 4 warning (level 4 warning are enabled if you pass /W4 to the compiler) for it
这篇博文:Visual C++ 是如此的自由，其中涵盖了这个扩展说明:
This blog post: Visual C++ is so Liberal which covers this extension notes that:
使用禁用语言扩展 (/Za) 会导致错误:
Using Disable Language Extensions (/Za) makes it an error:
这篇关于非常量引用绑定到临时的 Visual Studio 错误?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！