This project is an exploration of Makefiles. It demonstrates how a
hierarchy of makefiles can be designed to absolutely minimize the
amount of per-file and per-directory noise.

We draw on the ideas of Peter Miller’s Recursive Make Considered
Harmful[1]: Only one make instance runs, and it runs from the
project’s root directory.

We also assume a current GNU toolchain and rely heavily on features of
GNU make and GCC.

The project-specific information is in Makefile in the project root
and in a makefile called Dir.make in each directory. Each of those
can define any of four variables:

dirs – a list of subdirectories make should traverse
programs – a list of C programs in that directory
tests – a set of standalone C test programs in that directory
libs – a set of libraries in that directory

For each library libfoo listed in libs, the makefile should define
these variables.

libfoo_cfiles – a list of C source files in libfoo.

For each program foo listed in programs, the makefile should
define these variables.

foo_cfiles – a list of C source files in foo.
foo_libs – a list of project libraries that foo links against.

For each test program foo listed in tests, the makefile should
define these variables.

foo_cfiles – a list of C source files in foo.
foo_libs – a list of project libraries that foo links against.
foo_CPPFLAGS – extra C preprocessor flags to compile foo.

Makefile in the root directory MAY define libtype as either dynamic or
static, to globally set the type of libraries built. And Makefile
MUST end by including makefiles/toplevel.mk .

Here’s an example.

    programs := hello
hello_cfiles := hello.c

include makefiles/toplevel.mk

—
[1] http://miller.emu.id.au/pmiller/books/rmch/