I think you can get away with 'include' here -- the (Gnu only?) make behaviour on trying to include a non-existent file is to look for a target which creates th

I think you can get away with 'include' here -- the (Gnu only?) make behaviour on trying to include a non-existent file is to look for a target which creates that file, then running it if found, then to try the include again. This has other applications: if your Common.mk is generated by autoconf (say), then default: all Common.mk: $(error Not configured) include Common.mk gives a nicer error message if you 'make' having not './configure'd