问题
I'm working on trying to fix/redo the makefile(s) for a legacy system, and I keep banging my head against some things. This is a huge software system, consisting of numerous executables, shared objects, and libraries, using C, Fortran, and a couple of other compilers (such as Motif's UIL compiler). I'm trying to avoid recursive make and I would prefer "one makefile to build them all" rather than the existing "one makefile per executable/.so/.a" idea. (We call each executable, shared object, library, et al a "task," so permit me to use that term as I go forward.)
The system is scattered across tons of different source subdirectories, with includes usually in one of 6 main directories, though not always.
What would be the best way to deal with the plethora of source & target directories? I would prefer including a Task.mk file for each task that would provide the task-specific details, but target-specific variables don't give me enough control. For example, they don't allow me to change the source & target directories easily, at least from what I've tried.
Some things I cannot (i.e., not allowed to) do include:
Change the structure of the project. There's too much that would need to be changed everywhere to pull that off.
Use a different
make. The official configuration (which our customer has guaranteed, so we don't need to deal with unknown configurations) uses gmake 3.81, period.
来源：https://stackoverflow.com/questions/27256777/using-gmake-to-build-large-system