I have a VS Code CMake project which uses "Kits" to define the CMake builds:

[
    {
      "name": "Kit name (e.g. cross-compile)",
      "cmakeSettings": {
          ... some settings
      }
    }
]

In settings.json the kit is then used to define separate build dirs (e.g. so I can keep cross-compiled builds separate):

{
    ...
    "cmake.buildDirectory": "${workspaceFolder}/build-${buildKit}",
    ...
}

However, IntelliSense does not understand this in c_cpp_properties.json:

{
    "configurations": [
        {
            "name": "Foo",
            ...
            "compileCommands": "${workspaceFolder}/build-${command:cmake.buildKit}/compile_commands.json",
        }
    ],
    "version": 4
}

nor does it understand back in settings.json:

{
    "C_Cpp.default.compileCommands": "${workspaceFolder}/build-${buildKit}/compile_commands.json"
}

produces

"${workspaceFolder}/build-${buildKit}/compile_commands.json" could not be found. 'includePath' from c_cpp_properties.json in folder 'project' will be used instead.

even though both ${workspaceFolder} and ${buildKit} work in the same file for cmake.buildDirectory.

If I manually hardcode the location, IntelliSense works. If I do nothing (or one of the above), it can't find any include files.

What is the right way to point IntelliSense's compileCommand setting to the right CMake build directory?