C++ compiler options (flags)

[Uneau]

There is an example how to specify C compiler options, but nothing about C++.
How to specify C++ compiler options?

[Uneau]

Unlike "lang.c", c++ compiler requires "lang.cpp" key with "cxxflags" inside.
Example:

{
    "value": {
        "language": "c++"
    },
    "lang.cpp": {
        "cxxflags": [
            "-std=c++17",
            "-fpermissive"
        ]
    }
}