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• Automatic dependency handling;
• handling various types of input (.c, .cpp, .s, .S, .ll, .yy, ...);
• keeping source directories clean, i.e. building in seperate directories;
• allowing each module to specify what it builds and which flags it uses in addition to the global ones (through Makefile includes akin in syntax to automake "Makefile.am");
• distinguishing between "local" headers (for in-module use only) and "global" headers (external interface of modules);
• capability of building per-translation-unit test drivers, as the current tutorial does;
• no additional dependencies other than a recent version of GNU make (i.e., no $(shell ...) calls, one of the central improvements over the current tutorial);
• ...

Combuster wrote:Not that I'm expecting you to do all that.

Combuster wrote:- All features working on both cygwin and linux (And I might just as well add msys and MacOS to preempt some other converts.) Dependency file generation is a ***** to do right across platforms, same goes for unit tests. Stupid path conventions...).

Solar wrote:

• allowing each module to specify what it builds and which flags it uses in addition to the global ones (through Makefile includes akin in syntax to automake "Makefile.am");

Rusky wrote:...allow specific build instructions for specific files.

foo/obj/%.o: foo/src/%.c
	$(CC) $(CFLAGS) $(CFLAGS_foo) -c $< -o $@

bar/obj/%.o: bar/src/%.c
	$(CC) $(CFLAGS) $(CFLAGS_bar) -c $< -o $@

bin/someexe: $(someexe_OBJECTS) $(someexe_LIBRARIES)
	$(LD) $(LDFLAGS) $(LDFLAGS_someexe) $^ -o $@

• Macro functions and, possibly, pattern rules. Exactly which macro functions will make it in (pun intended) is still an open discussion. To give an example, SunPro handles GNU make's addprefix and addsuffix functionality with pattern macro expansions.
• The addition of several assignment operators: !=, +=, ?=, and (probably) ::=. The latter would be equivalent to GNU's :=, which would not be suitable for standardization due to the fact that it breaks common practice, particularly on BSD and Solaris. As for !=, it's been around in *BSD for ages and is now also available in GNU make's trunk.
• Silent includes (via -include). It wasn't discussed yet, but the ability to include multiple pathnames on one line is also very important. The following two bullet point goes hand in hand with this one.

Combuster wrote:Dependency file generation is a ***** to do right across platforms

• Automatic dependency generation. This isn't really an enhancement to the make utility itself but it's something the tutorial would need to cover anyway. I was the one to make this particular proposal; right now, we're discussing which solution would make most sense: GCC's -M? family of switches (it breaks compatibility with some environments, such as MKS), GCC's DEPENDENCIES_OUTPUT environment variable---SunPro provides SUNPRO_DEPENDENCIES which is similar except it doesn't exclude system headers, or the separate makedepend utility (except there are a couple of issues with its current incarnation---i.e., the fact that it has no flag to ignore system headers, the non-standard -include flag, and the -- thingy which only makes sense as an extension).
• The ability to use dashes in macro names.

Rusky wrote:It would be more for other types of sources...

Rusky wrote:...or for simple third-party sources like glew.c that don't need their own library.

Rusky wrote:...another nice thing to have would be command-line overrides of build flags...

Love4Boobies wrote:For the record, POSIX:2008 TC1 will enhance standard make a great deal (enough to finally make it useful) so this time it might actually be worth waiting until it comes out or at least refactoring the tutorial so that it covers portable makefiles instead.