all: targetfile

targetfile: subproject/targetfile intermediatefile
    somecommand1

intermediatefile: sourcefile1 resourcesobj
    somecommand2

resourcesobj: sourcefile2 patchedsubprojectfile
    somecommand3

patchedsubprojectfile: subproject/targetfile
    somecommand4

subproject/targetfile: subprojectphony

subprojectphony:
    @$(MAKE) -C subproject

.PHONY: all subprojectphony