capture error

this is a classic error that happens when you don’t use automatic rules :

a.o : a.c
    gcc -c -o b.o a.c

main.o : main.c
	gcc -c -o $@ $^

app : a.o main.o
    gcc -o $@ $^

when running make, you won’t get an error because you will compile correctly, but you will get b.o instead of expected a.o. In the next steps of the build, linking app will fail because a.o does not exist, or, worse, it was not updated and you have a wrong version. This error is hard to spot.

after build, yamake checks that the target file exists.