PS F:\cst_proj\cpp20> xmake build
[  0%]: generating.module.deps hh.a.cpp
[  0%]: generating.module.deps hh.b.cpp
[  0%]: generating.module.deps main.cpp
[  0%]: generating.module.deps hh.a.ixx
[  0%]: generating.module.deps hh.b.ixx
[  0%]: generating.module.deps hh.ixx
[  0%]: generating.module.deps hh.types.ixx
[  8%]: compiling.module.release hh:types

// hh.ixx
export module hh;
export import :a;
export import :b;

// hh.types.ixx
export module hh:types;
export class A;
export class B;

// hh.a.ixx
#include <iostream>

export module hh:a;

import :types;

export class A {
private:
	B* b = nullptr;
public:
	static void say() {
		std::cout << "A class" << std::endl;
	}
	int getInt() { return (int)'A'; }
	int getInt2();
};

export void say() {

}

// hh.a.cpp
module hh:a;
import :b;

int A::getInt2() {
	this->b = new B();
	this->b->getInt();
	return 100;
}

// hh.b.ixx
#include <memory>
export module hh:b;
import :types;

export class B {
private:
	A* a = nullptr;
public:
	int getInt();
};

// hh.b.cpp
#include <memory>
module hh:b;
import :a;

int B::getInt() {
	this->a = new A();
	this->a->getInt();
	return 100;
}

// main.cpp
#include <iostream>

import hh;

int main(int argc, char* argv) {
	std::cout << "ssss" << std::endl;
	B b;
	A a;
	std::cout << b.getInt() << a.getInt() << std::endl;
	return 0;
}

// xmake.lua
add_rules("mode.debug", "mode.release")

set_languages("c++20")

toolchain("clang17")
    set_kind("standalone")
    set_sdkdir("D:\\LLVM")
toolchain_end()

target("cpp20")
    set_kind("binary")
    add_files("*.cpp", "*.ixx")