Error when building with g++-13

[Bernnardo Oliveira]

Hi there folks, hope you are doing well

I'm currently figuring out a way to integrate some graph libs to the ns3 source code and i was stumbled by this issue.

Usually, I compile ns3 source code with g++ 9.4 and everything works out fine, but because one of these graph libs (in this case, one that I'm not going to use) uses a lot of C++20 standard features, I switched to version g++ 13 (Ubuntu 20.04).

When I tried to build ns3, a lot of errors were raised by the compiler (Errors such as std::uint8_t not in std scope, etc). After doing some research, I discovered that these errors may be associated with a compiler that is not compliant with the C++11 standard. 

Anyway, it's not really an issue since I don't need to use this version of g++, but i thought it was worth sharing since this could help someone with a similar problem.

Furthermore, has anybody also faced this problem?

[Bernnardo Oliveira]

This can be checked in https://gcc.gnu.org/gcc-13/porting_to.html

[Tommaso Pecorella]

We moved to C++20 recently, and ns-3 is tested also with gcc-13, so my best guess is that you're referring to an old ns-3 version...

The quickest solution for your case would be to upgrade your ns-3 to 3.41. A more painful way is to back port some of the changes we made.

[Bernnardo Oliveira]

Oh of course, somehow this went over my head. Thank you Tommaso and sorry for wasting your time with this