How to pass target name to list of sub-makefiles?

Question

I have a setup like this: ``` /Makefile /foo/Makefile /foo/bar/Makefile /foo/baz/Makefile ``` The top-level Makefile contains a task which calls the `/foo/Makefile`. This Makefiles creates a list of makefiles in the subdirectories (`bar`, `baz` in the example). For each subdir, it calls the Makefiles: ``` $(SUB_DIRS): $(MAKE) -C $@ ``` Which is fine for, say, the `all` task. But if I want to do something else, I get stuck. Is there a possibility to pass the target to the list of sub-makefiles? For example: ``` $(SUB_DIRS): $(MAKE) -C $@ <task> clean: $(SUB_DIRS)-clean # or something? ``` Or is my whole concept wrong?

Accepted Answer

You could simply use the `MAKECMDGOALS` variable:

Make will set the special variable `MAKECMDGOALS` to the list of goals you specified on the command line. If no goals were given on the command line, this variable is empty.

```
$(SUB_DIRS):
    +$(MAKE) -C $@ $(MAKECMDGOALS)
```

The `+` sign is important so the underlying job server also handles the recursive make calls with the right amount of threads/core.

You can also use the `$(foreach )` function like this:

```
clean:
    $(foreach DIR, $(SUB_DIRS), $(MAKE) -C $(DIR) $@;)
```

Do note as @musicmatze mentionned in the comments that Make flags (like `-j`) won't be passed to the sub-make processes correctly here.

How to pass target name to list of sub-makefiles?

Solution

Problem