Examples

#Source: https://learning.edx.org/course/course-v1:Dartmouth_IMTx+DART.IMT.C.07+1T2020/home
 
 
# define the C compiler to use
CC       = gcc
# define comipler flags
CFLAGS   = -std=c11 -Wall -fmax-errors=10 -Wextra
# define library paths in addition to /usr/lib
LFLAGS   = -L. 
# define libraries to use
LIBS     = -lweather
# define the object files that this project needs
OBJFILES = program.o
# define the name of the executable file
MAIN     = program
 
# all of the below is generic - one typically only adjusts the above
 
all: $(MAIN)
 
$(MAIN): $(OBJFILES)
    $(CC) $(CFLAGS) -o $(MAIN) $(OBJFILES) $(LFLAGS) $(LIBS) 
 
%.o: %.c
    $(CC) $(CFLAGS) -c -o $@ $<
 
launch: program
	./program
 
clean:
    rm -f $(OBJFILES) $(MAIN)
Intermediate step:
 
program: program.o
	gcc -std=c11 -Wall -fmax-errors=10 -Wextra program.o -L. -lweather -o program
 
program.o: program.c
	gcc -std=c11 -Wall -fmax-errors=10 -Wextra -c program.c -o program.o
 
launch: program
	./program

# Thanks to Job Vranish (https://spin.atomicobject.com/2016/08/26/makefile-c-projects/)
TARGET_EXEC := final_program
 
BUILD_DIR := ./build
SRC_DIRS := ./src
 
# Find all the C and C++ files we want to compile
# Note the single quotes around the * expressions. The shell will incorrectly expand these otherwise, but we want to send the * directly to the find command.
SRCS := $(shell find $(SRC_DIRS) -name '*.cpp' -or -name '*.c' -or -name '*.s')
 
# Prepends BUILD_DIR and appends .o to every src file
# As an example, ./your_dir/hello.cpp turns into ./build/./your_dir/hello.cpp.o
OBJS := $(SRCS:%=$(BUILD_DIR)/%.o)
 
# String substitution (suffix version without %).
# As an example, ./build/hello.cpp.o turns into ./build/hello.cpp.d
DEPS := $(OBJS:.o=.d)
 
# Every folder in ./src will need to be passed to GCC so that it can find header files
INC_DIRS := $(shell find $(SRC_DIRS) -type d)
# Add a prefix to INC_DIRS. So moduleA would become -ImoduleA. GCC understands this -I flag
INC_FLAGS := $(addprefix -I,$(INC_DIRS))
 
# The -MMD and -MP flags together generate Makefiles for us!
# These files will have .d instead of .o as the output.
CPPFLAGS := $(INC_FLAGS) -MMD -MP
 
# The final build step.
$(BUILD_DIR)/$(TARGET_EXEC): $(OBJS)
	$(CXX) $(OBJS) -o $@ $(LDFLAGS)
 
# Build step for C source
$(BUILD_DIR)/%.c.o: %.c
	mkdir -p $(dir $@)
	$(CC) $(CPPFLAGS) $(CFLAGS) -c $< -o $@
 
# Build step for C++ source
$(BUILD_DIR)/%.cpp.o: %.cpp
	mkdir -p $(dir $@)
	$(CXX) $(CPPFLAGS) $(CXXFLAGS) -c $< -o $@
 
 
.PHONY: clean
clean:
	rm -r $(BUILD_DIR)
 
# Include the .d makefiles. The - at the front suppresses the errors of missing
# Makefiles. Initially, all the .d files will be missing, and we don't want those
# errors to show up.
-include $(DEPS)