rm -rf /tmp/out/library
rm -rf /tmp/out/executable
Asking for the sublibrary to be built:
$ cd /src
$ make -n clean-library_sublibrary
rm -rf /tmp/out/library/sublibrary
$ make -n library_sublibrary
cc -c -o '/tmp/out/library/sublibrary/slib1.o' '/home/jgc/doc/nonrecursive/library/sublibrary/slib1.c'
cc -c -o '/tmp/out/library/sublibrary/slib2.o' '/home/jgc/doc/nonrecursive/library/sublibrary/slib2.c'
ar r '/tmp/out/library/sublibrary/slib.a' /tmp/out/library/sublibrary/slib1.o /tmp/out/library/sublibrary/slib2.o
ranlib '/tmp/out/library/sublibrary/slib.a'
And if we ask that the executable module be built the library gets built at the same time because of the dependency (and also the sublibrary):
$ cd /src/executable
$ make -n executable
cc -c -o '/tmp/out/library/sublibrary/slib1.o' '/home/jgc/doc/nonrecursive/library/sublibrary/slib1.c'
cc -c -o '/tmp/out/library/sublibrary/slib2.o' '/home/jgc/doc/nonrecursive/library/sublibrary/slib2.c'
ar r '/tmp/out/library/sublibrary/slib.a' /tmp/out/library/sublibrary/slib1.o /tmp/out/library/sublibrary/slib2.o
ranlib '/tmp/out/library/sublibrary/slib.a'
cc -c -o '/tmp/out/library/lib1.o' '/home/jgc/doc/nonrecursive/library/lib1.c'
cc -c -o '/tmp/out/library/lib2.o' '/home/jgc/doc/nonrecursive/library/lib2.c'
ar r '/tmp/out/library/lib.a' /tmp/out/library/lib1.o /tmp/out/library/lib2.o
ranlib '/tmp/out/library/lib.a'
cc -c -o '/tmp/out/executable/foo.o' '/home/jgc/doc/nonrecursive/executable/foo.c'
cc -c -o '/tmp/out/executable/bar.o' '/home/jgc/doc/nonrecursive/executable/bar.c'
g++ /tmp/out/executable/foo.o /tmp/out/executable/bar.o /tmp/out/library/lib.a -o'/tmp/out/executable/exec'
Conclusion
Although nothing like as simple as recursive Make, this non-recursive system is
very flexible (allowing dependencies between individual binary files across modules; that's not possible with recursive Make) without losing the 'go to any directory and type Make' that engineers are familiar with.
Let me know if you use it, or improve on it.
About the author
John Graham-Cumming is Co-Founder at Electric Cloud, Inc . Prior to joining Electric Cloud, John was a Venture Consultant with Accel Partners, VP of Internet Technology at Interwoven, Inc. (IWOV), VP of Engineering at Scriptics Corporation (acquired by Interwoven), and Chief Architect at Optimal Networks, Inc. John holds BA and MA degrees in Mathematics and Computation and a Doctorate in Computer Security from Oxford University. John is the creator of the highly acclaimed open source POPFile project. He also holds two patents in network analysis and has others pending.
