C++ Error 'nullptr was not declared in this scope' in Eclipse IDE

Question

I am running Eclipse Helios and I have g++-4.6 installed. Hope I am not wrong that g++4.6 implements C++ 11 features. I have created a C++ project which uses the nullptr and aut

Answer 1

Go to Settings -> Compiler... And add flag to "Have g++ follow the coming C++0x ISO C++ language standard [std=c++0x]

Answer 2

According to the GCC page for C++11:

To enable C++0x support, add the command-line parameter -std=c++0x to your g++ command line. Or, to enable GNU extensions in addition to C++0x extensions, add -std=gnu++0x to your g++ command line. GCC 4.7 and later support -std=c++11 and -std=gnu++11 as well.

Did you compile with -std=gnu++0x ?

Answer 3

I add the ",-std=c++0x" after "-c -fmessage-length=0"，under Project Properties -> C/C++ Build -> Settings -> GCC C++ Compiler -> Miscellaneous. Dont't forget to add the comma "," as the seperator.

Answer 4

Finally found out what to do. Added the -std=c++0x compiler argument under Project Properties -> C/C++ Build -> Settings -> GCC C++ Compiler -> Miscellaneous. It works now!

But how to add this flag by default for all C++ projects? Anybody?

Answer 5

Is that an actual compiler error or a Code Analysis error? Some times the code analysis can be a bit sketchy and report non-valid errors.

To turn off code analysis for the project, right click on your project in the Project Explorer, click on Properties, then go to the C/C++ General tab, then Code Analysis. Then click on "Use Project Settings" and disable the ones that you do not wish for.

Also, are you sure you are compiling with the C++11 compiler?

Answer 6

Trying with a different version of gcc worked for me - gcc 4.9 in my case.