Question

I am new to makefile. I have a makefile with following statement:

....

all: prepare hreader $(DIRS)
    echo $(DIRS)

.PHONY: prepare hreader $(DIRS)

prepare:                              
    mkdir -p ./lib
    $(MAKE) -C game_proc prepare     #here, why 'prepare'?!

hreader:
    make -C extra/hreader

$(DIRS):
    $(MAKE) -C $@

In my makefile directory, i have a ‘game_proc’ directory. And from GNU make tutorial, i know that below lines

prepare:                           
    mkdir -p ./lib
    $(MAKE) -C game_proc

will do a recursive make on ‘game_proc’.

But why ‘prepare’ also appear in the recipe? Now how do i interpret ‘$(MAKE) -C game_proc prepare’? It does a recursive make on ‘game_proc’, and what? also a recursive make on ‘prepare’?

Thanks,

Answer 1

A phony target just tells make that the rule is not going to create an output file of that name.

Update after comments

Ok, it’s important to realize that there are two separate makefiles here at play:

./Makefile

and

game_proc/Makefile

The confusion results from there being a prepare target in both Makefiles.

I.e., there is in game_proc/Makefile a target prepare. Let’s for a moment rename that target to prepare2 so that the situation becomes clearer:

./Makefile:

    .PHONY: prepare hreader $(DIRS)

prepare:                              
    mkdir -p ./lib
    $(MAKE) -C game_proc prepare2 # refers to game_proc/Makefile's prepare2 target

game_proc/Makefile:

prepare2:
    ...