Minimal-configuration "universal" makefile for medium-scale C/C++ projects

Makefile

# "Universal" Makefile
# Imani Pelton (@bepri on GitHub)
# A plug-n-play Makefile for any medium-scale C/C++ project. Probably not as powerful as CMake, but sufficient if you don't want to use all that.
# Uses a target directory with object file outputs to speed up compilation times on multi-file projects

# Modify these for your program
COMP = g++
COMPFLAGS = -g -Wall -Wpedantic -Werror -D DEBUG
PROGNAME = prog

# Fill in after the ?= if you want to skip specifying these from the command line
LINKFLAGS ?=
PROGFLAGS ?= 

# Do not modify below here (unless you want to understand all this garbage)

# Select the expected source file extension
EXT = $(if $(filter $(COMP),g++),pp)
# Get a list of all the subdirectories in src/ in the form of their corresponding target/obj/ dirs
SRC_SUBDIRS = $(patsubst src/%, target/obj/%, $(sort $(dir $(wildcard src/**/*.c$(EXT)))))

.PHONY: all
all: setup target/$(PROGNAME)

# Compile the final binary, depending on all related .o files
target/$(PROGNAME): $(patsubst src/%.c$(EXT), target/obj/%.o,\
					$(wildcard src/**/*.c$(EXT)))
  # Compile from recipe dependencies, but ignore .h files (we wanted to track those, but they do not get compiled directly)
	$(COMP) -o $@ $(filter-out %.h$(EXT),$^) $(LINKFLAGS)

# Create all the .o files
target/obj/%.o: src/%.c$(EXT) $(wildcard src/*.h$(EXT))
	$(COMP) $(COMPFLAGS) -c -o $@ $<

# Create the desired structure for the target directory
.PHONY: setup
setup:
	mkdir -p target/obj $(SRC_SUBDIRS)

# Clean rebuild
.PHONY: fresh
fresh: clean all

# Set up a development directory in the format this makefile expects
.PHONY: init
init: setup
	mkdir src

.PHONY: run
run: all
	./target/$(PROGNAME) $(PROGFLAGS)

.PHONY: clean
clean:
	rm -f target/obj/* target/$(PROGNAME)

.PHONY: help
help: 
	@echo "Variables:"
	@echo "	   PROGFLAGS: flags to pass to your program if executing via make"
	@echo "    LINKFLAGS: desired linking flags for compilation (should include the -L)"
	@echo "Available recipes:"
	@echo "    all: build project"
	@echo "    setup: create build directory"
	@echo "    fresh: delete all build artifacts and outputs, then rebuild"
	@echo "    init: creates a src directory this Makefile will check"
	@echo "    run: runs your program. specify flags to your program like \"make run PROGFLAGS=-m\""
	@echo "    clean: deletes all build artifacts and outputs"