Re: how make interprets directory which are prerequisites

[John Graham-Cumming]

sharan basappa wrote:
> lib_codec := lib/codec
> lib_db := lib/db
> lib_ui := lib/ui
> libraries := $(lib_ui) $(lib_db) $(lib_codec)
> player := app/player
> .PHONY: all $(player) $(libraries)
> all: $(player)
> $(player) $(libraries):
> $(MAKE) --directory=$@
> $(player): $(libraries)
> $(lib_ui): $(lib_db) $(lib_codec)

Since you declared those directories as phony they will always be 
considered to be out of date.  That means that in your example if you 
'make all' (or just 'make') then you will always recurse into the player 
and libraries subdirectories, and the libraries will be built before the 
player.

This looks just like the totally standard way of handling recursion into 
sub-directories outlined in the GNU Make manual here: 
http://www.gnu.org/software/make/manual/make.html#Phony-Targets

John.