I have been having troubles getting my makefiles to work the way I want. First off, I would like to say this is POSIX make, as in http://www.opengroup.org/onlinepubs/009695399/utilities/make.html I am needing my build system to work with both BSDs and GNUs(Linux).
What I am wanting is a zero maintenance makefile. I want it to just compile all .c and .asm files in src/ and place the object files in objs/ and then to link everything in objs/ to a binary file.
I can do a lot, but I can't get it to separate the source and obj files.
I am ok if this requires a little built-in shell scripting (using POSIX defined /bin/sh), but I can just not get the dependencies to work right. I want it to only build the object file if the source file is newer.
My closest is this:
${C_OBJS}: ${HDRS} ${*:objs/%=src/%}.c ${CC} ${CFLAGS} -c ${*:objs/%=src/%}.c -o $*.o
This has the problem that I must still specify C_OBJS=objs/foo.o and such and also it is just barely not POSIX and therefore, compiles with BSD make but not GNU make.