c ++ initializer_list和shared_ptr行为

本文介绍了c ++ initializer_list和shared_ptr行为的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我正在测试vs2013 c ++ initializer_list。

I'm testing vs2013 c++ initializer_list.

下面的代码可以编译。
但是当我运行exe时崩溃。

The code below can be compiled.But crashes when i run exe.

#include <memory>
#include <iostream>

class Base {};

class Derived : public Base {};

void DoSomething(std::initializer_list<std::shared_ptr<Base> > list)
{
}

int main()
{
  auto ip = std::make_shared<Derived>();

  std::cout << "use_count=" << ip.use_count() << std::endl;

  DoSomething({ip, std::make_shared<Derived>()}); // ng
  // DoSomething({ip, std::make_shared<Base>()}); // ok
  // DoSomething({std::make_shared<Derived>(), ip}); // ok

  std::cout << "use_count=" << ip.use_count() << std::endl;
}

编译。

C:\...>cl.exe /EHsc test.cpp
Microsoft(R) C/C++ Optimizing Compiler Version 18.00.21005.1 for x86
Copyright (C) Microsoft Corporation.  All rights reserved.

test.cpp
Microsoft (R) Incremental Linker Version 12.00.21005.1
Copyright (C) Microsoft Corporation.  All rights reserved.

/out:test.exe
test.obj

C:\...>

我期望的输出像这样。
g ++ 4.8.2就像这样。

I expected the output like this.g++4.8.2 works like this.

c:\...>test.exe
use_count=1
use_count=1

但是， / p>

However, looks like this.

c:\...>test.exe
use_count=1
use_count=0 // or some random value like 3719232 and displayed crash dialog.

然后，修改上面的代码中的一行，这很好。

And, Modifying one line of the code above, This works good.

DoSomething({std::make_shared<Derived>(), ip});

这是vs2013 initializer_list的错误还是正常的行为？

Is this a bug or normal behavior of vs2013 initializer_list ?

Feedback

c ++ initializer_list和shared_ptr行为

问题描述

推荐答案