make: "directive-ifmake.mk" line 8: ok: positive condition works
make: "directive-ifmake.mk" line 19: ok: negation works
make: "directive-ifmake.mk" line 25: ok: double negation works
make: "directive-ifmake.mk" line 32: ok: both mentioned
make: "directive-ifmake.mk" line 39: ok: only those mentioned
make: "directive-ifmake.mk" line 49: Targets can even be added at parse time.
: first
: second
: late-target
exit status 0