https://stackoverflow.com/questions/68136230

+coverage from multiple compilation units.md

This repo was created in response to https://stackoverflow.com/questions/68136230

common.c

#include<stdio.h>
void fun1(){
        printf("fun1\n");
}

void fun2(){
        printf("fun2\n");
}

Makefile

.PHONY: help question answer answer-gcovr clean

help:
	@echo "Available targets:"
	@echo "  make question"
	@echo "  make answer"
	@echo "  make answer-gcovr"

clean:
	rm -rf ut1 ut2 *.gcda *.gcno *.o *.json coverage.*

question: clean
	gcc -Wall -fprofile-arcs -ftest-coverage ut1.c common.c -o ut1
	gcc -Wall -fprofile-arcs -ftest-coverage ut2.c common.c -o ut2
	./ut1
	./ut2
	gcov common.c
	cat common.c.gcov

answer: clean
	gcc -Wall --coverage -c common.c -o common.o
	gcc -Wall --coverage ut1.c common.o -o ut1
	gcc -Wall --coverage ut2.c common.o -o ut2
	./ut1
	./ut2
	gcov common.c
	cat common.c.gcov

answer-gcovr: clean
	gcc -Wall --coverage ut1.c common.c -o ut1
	./ut1
	gcovr --json ut1.json
	rm *.gcda *.gcno

	gcc -Wall --coverage ut2.c common.c -o ut2
	./ut2
	gcovr --json ut2.json

	gcovr -a ut1.json -a ut2.json --html-details coverage.html

ut1.c

#include<stdio.h>
void fun1();
int main(){
    fun1();
}

ut2.c

#include<stdio.h>
void fun2();
int main(){
    fun2();
}