Eclipse CDT Oxygen: Compiler issue

I'm running Ubuntu 16.04 and just opened my freshly installed Eclipse CDT Oxygen for the first time.

I imported an existing C++ project that builds fine using a CMake file that sets add_definitions(-std=c++11).

I used CMake with the command cmake -G"Eclipse CDT4 - Unix Makefiles" -D CMAKE_BUILD_TYPE=Debug ../src/ to generate Eclipse project files and then used those to import the project into Eclipse.

Now I'm looking at a source file in my newly imported project inside Eclipse and see a ton of issues. It's all types that cannot be resolved, for example std::default_random_engine.

My guess is that Eclipse doesn't have the right toolchain configured.

I have a few questions:

1. How can I see the toolchain for my project and how can I change it? I looked up this help article, but the sections in the project properties menu I see are not the same as in the help article. The project properties menu I see does not have a "C/C++ Build" section. How can that be?

2. The CMake file that I used to generate the Eclipse project files specifies that C++11 is supposed to be used, so why isn't this the case then?

Thanks a lot!