Makefile PHONY targets fail using test command

The following simple PHONY target for Makefile is failing:

dir=/etc
file=fstab
install:
        -test ! -f $(dir)/$(file)

Error displayed:

make install
-I/root/module
test ! -f /etc/fstab
make: [install] Error 1 (ignored)

If I remove the ! symbol from the condition, there is no issue. Can someone help me to sort out this issue? I hope this is a bug in bash/Makefile targets.