我在日食朱诺号上也遇到了同样的问题。这些步骤解决了问题:

进入“项目->属性-> C/ c++通用->路径和符号->选项卡[符号]。 添加符号:__cplusplus，值为201103L

我在Eclipse论坛上找到了这篇文章，只需要按照这些步骤，它就适合我了。我在Windows上使用Cygwin设置的Eclipse Indigo 20110615-0604。

Make a new C++ project Default options for everything Once created, right-click the project and go to "Properties" C/C++ Build -> Settings -> Tool Settings -> GCC C++ Compiler -> Miscellaneous -> Other Flags. Put -std=c++0x (or for newer compiler version -std=c++11 at the end . ... instead of GCC C++ Compiler I have also Cygwin compiler C/C++ General -> Paths and Symbols -> Symbols -> GNU C++. Click "Add..." and paste __GXX_EXPERIMENTAL_CXX0X__ (ensure to append and prepend two underscores) into "Name" and leave "Value" blank. Hit Apply, do whatever it asks you to do, then hit OK.

现在在Eclipse FAQ/ c++ 11 Features中也有关于这方面的描述。

Eclipse设置

Eclipse C/ c++不识别符号std::unique_ptr，即使您在文件中包含了c++ 11内存头文件。

假设你正在使用GNU c++编译器，这是我所做的修复:

项目->属性-> C/ c++通用->预处理器包括路径-> GNU c++ -> CDT用户设置条目

点击“Add…”按钮 从下拉菜单中选择“预处理宏” 名称:__cplusplus值:201103L 点击Apply，然后OK回到你的项目 然后重建你的c++索引:Projects -> C/ c++索引->重建

当使用交叉编译器时，我经常得到同事精心设计的高级自定义构建系统。我使用“现有代码的Makefile项目”，所以大多数其他答案都不适用。

At the start of the project, I have to specify that I'm using a cross compiler in the wizard for "Makefile Project with Existing Code". The annoying thing is that in the last 10 or so years, the cross compiler button on that wizard doesn't prompt for where the cross compiler is. So in a step that fixes the C++ problem and the cross compiler problem, I have to go to the providers tab as mentioned by answers like @ravwojdyla above, but the provider I have to select is the cross-compiler provider. Then in the command box I put the full path to the compiler and I add -std=gnu++11 for the C++ standard I want to have support for. This works out as well as can be expected.

您可以对现有项目执行此操作。您可能需要做的唯一一件事就是重新运行索引器。

我从未需要添加experimental标志或重写__cplusplus的定义。 唯一的问题是，如果我有大量的现代C代码，我就无法放置特定于C的标准选项。

当情况非常糟糕时，在Indexer子菜单中使用该命令获取解析器日志，可以提供非常丰富的信息。

无论是hack版本还是更干净的版本都不能用于Indigo。黑客被忽略，所需的配置选项丢失。没有明显的原因，构建在不能工作后开始工作，并且没有提供任何有用的原因。至少从命令行，我得到了可重复的结果。

我还不能评论，所以我写了我自己的答案:

它与__GXX_EXPERIMENTAL_CXX0X__相关，对Eclipse Juno和CDT 8.x有效。

这个答案的一些部分已经在其他答案中涵盖了，但我希望它是连贯的。

为了能够使用stdc++11构建，必须为编译器添加特定的标志。您可以通过项目属性来实现这一点。修改项目属性RMB和项目属性或ALT + ENTER。然后C/ c++构建->设置->工具设置-> GCC c++编译器-> Miscellaneous ->其他标志。将-std=c++11放在行末，对于GCC来说，它看起来像这样:-c -fmessage-length=0 -std=c++11。通过添加-stdc++11标志，编译器(GCC)将自己声明__GXX_EXPERIMENTAL_CXX0X__。

此时，您可以使用c++ 11的所有优点来构建项目。

The problem is that Eclipse has it's own parser to check for errors - that's why you're still getting all the nasty errors in Eclipse editor, while at the same time you can build and run project without any. There is a way to solve this problem by explicitly declaring __GXX_EXPERIMENTAL_CXX0X__ flag for the project, one can do that (just like Carsten Greiner said): C/C++ General -> Paths and Symbols -> Symbols -> GNU C++. Click "Add..." and past __GXX_EXPERIMENTAL_CXX0X__ (ensure to append and prepend two underscores) into "Name" and leave "Value" blank. And now is the extra part I wanted to cover in comment to the first answer, go to: C/C++ General -> Preprocessor Include Path Macros etc. -> Providers, and Select CDT Managed Build Setting Entries then click APPLY and go back to Entries tab, under GNU C++ there should be now CDT Managed Build Setting Entries check if inside there is defined __GXX_EXPERIMENTAL_CXX0X__ if it is -> APPLY and rebuild index you should be fine at this point.