CMAKE_UNITY_BUILD and CXX_MODULES

Development
1

I am wondering why CMAKE_CXX_SCAN_FOR_MODULES disables UNITY_BUILD on all plattforms?

2

Modules-using TUs cannot be combined into unity sources.

Basically, post-#include, module sources look like:

import foo;

int implstuff() {
    return 0;
}

import bar; // error: imports belong at the top of the file.

int moreimpl() {
    return 1;
}