Question

so I learned what a Makefile was some time ago, created a template Makefile and all I do is copy and alter the same file for every program I’m doing. I changed it a few times, but it’s still a very crude Makefile. How should I improve it? This is an example of my current version:

CC  = g++
CFLAGS  = -std=gnu++0x -m64 -O3 -Wall  
IFLAGS  = -I/usr/include/igraph
LFLAGS  = -ligraph -lgsl -lgslcblas -lm 
DFLAGS  = -g -pg

# make all
all: run test                   

# make a fresh compilation from scratch 
fresh: clean test                

#makes the final executable binary
run: main.o foo1.o foo2.o              
    $(CC) $(CFLAGS) $(LFLAGS) $^ -o $@

#makes the test executable with debugging and profiling tags
test: test.o foo1.o foo2.o 
    $(CC) $(DFLAGS) $(CFLAGS) $(LFLAGS) $^ -o $@

#makes teste.o
teste.o: teste.cpp
    $(CC) $(CFLAGS) $(IFLAGS) -c $^ -o $@

#makes main.o
main.o:  main.cpp
    $(CC) $(CFLAGS) $(IFLAGS) -c $^ -o $@   

#file foo1
foo1.o: foo1.cpp
    $(CC) $(CFLAGS) $(IFLAGS) -c $^ -o $@   

#file foo2
foo2.o: foo2.cpp
    $(CC) $(CFLAGS) $(IFLAGS) -c $^ -o $@   

clean: clean-test clean-o clean-annoying

clean-test:
    rm test-rfv

clean-o:
    rm *.o -rfv

clean-annoying:
    rm *~  -rfv

Just by visually comparing with other makefiles I saw around in the web, this seems to be not a very bright Makefile. I don’t know how they work, but I can see there’s significantly less boilerplate and more generic code in them.

Can this can be made better, safer, and easier to particularize for each project?

Answer 1

You don’t want to name specific files in a makefile if you can get away with it, and 99% of the time you can. This page shows how to develop a very general makefile. The following is my own makefile, based on that page’s info:

SHELL := bash
PROG := pathed.exe

OUTDIRS := bin/debug bin/rel obj/debug obj/rel

PROG_REL := bin/rel/$(PROG)
PROG_DEBUG := bin/debug/$(PROG)

SRCFILES := $(wildcard src/*.cpp)

OBJFILES_REL := $(patsubst src/%.cpp,obj/rel/%.o,$(SRCFILES))
OBJFILES_DEBUG := $(patsubst src/%.cpp,obj/debug/%.o,$(SRCFILES))

DEPFILES := $(patsubst src/%.cpp,obj/%.d,$(SRCFILES))

CFLAGS := -Iinc -Wall -Wextra  -MMD -MP
DBFLAGS := -g
RELFLAGS := 

CC := g++

.PHONY: default all testmake debug release clean dirs

default: debug 

all:    dirs clean debug release

dirs: 
    @mkdir -p  $(OUTDIRS)

debug:  $(PROG_DEBUG)

release: $(PROG_REL)

testmake:
    @echo OBJFILES_REL = $(OBJFILES_REL)
    @echo OBJFILES_DEBUG = $(OBJFILES_DEBUG)
    @echo SRCFILES = $(SRCFILES)
    @echo DEPFILES = $(DEPFILES)

clean:
    rm -f $(OBJFILES_REL) $(OBJFILES_DEBUG) $(DEPFILES) $(PROG)

$(PROG_REL): $(OBJFILES_REL)
    $(CC)  $(OBJFILES_REL) -o $(PROG_REL)
    strip $(PROG_REL)
    @echo "----  created release binary ----"


$(PROG_DEBUG): $(OBJFILES_DEBUG)
    $(CC) $(OBJFILES_DEBUG) -o $(PROG_DEBUG)
    @echo "----  created debug binary ----"

-include $(DEPFILES)

obj/rel/%.o: src/%.cpp
    $(CC) $(RELFLAGS) $(CFLAGS) -MF $(patsubst obj/rel/%.o, obj/%.d,$@) -c $< -o $@

obj/debug/%.o: src/%.cpp
    $(CC) $(DBFLAGS) $(CFLAGS) -MF $(patsubst obj/debug/%.o, obj/%.d,$@) -c $< -o $@