Why does make think the target is up to date?

my mistake was making the target name "filename.c:" instead of just "filename:"

EDIT: This only applies to some versions of make - you should check your man page.

You can also pass the -B flag to make. As per the man page, this does:

-B, --always-make Unconditionally make all targets.

So make -B test would solve your problem if you were in a situation where you don't want to edit the Makefile or change the name of your test folder.

Maybe you have a file/directory named test in the directory. If this directory exists, and has no dependencies that are more recent, then this target is not rebuild.

To force rebuild on these kind of not-file-related targets, you should make them phony as follows:

.PHONY: all test clean

Note that you can declare all of your phony targets there.

A phony target is one that is not really the name of a file; rather it is just a name for a recipe to be executed when you make an explicit request.

It happens when you have a file with the same name as Makefile target name in the directory where the Makefile is present.