gcc 11 module example

helloworld.cxx

export module helloworld;  // module declaration
import <iostream>;         // import declaration
 
export void hello() {      // export declaration
    std::cout << "Hello world!\n";
}

main.cpp

import helloworld;  // import declaration
 
int main() {
    hello();
}

Makefile

all: hello

gcm.cache:
	g++ -std=c++20 -fmodules-ts -xc++-system-header iostream

helloworld.o: helloworld.cxx gcm.cache
	g++ -std=c++20 -fmodules-ts -c helloworld.cxx -o helloworld.o

hello: helloworld.o
	g++ -std=c++20 -fmodules-ts main.cpp helloworld.o -o hello 


clean:
	rm -fr gcm.cache
	rm -f helloworld.o hello

.PHONY: all clean