Makefile - move object files

Question

After a bit of searching, I\'ve managed to throw together the following Makefile:

CC = gcc
CFLAGS = -c -Wall
LDFLAGS = 
SOURCEFILES = main.c
SOURCES = src/$(         


        

Answer 1

Something like this?

SOURCES = src/main.c
OBJECTS = obj/main.o

...

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

Once that's working, you can add further tricks, like this:

OBJECTS = $(patsubst src/%.c, obj/%.o, $(SOURCES)

Answer 2

The trick is to not move your objects.
You should build it and use it from where they are built.

For example you have the following directory structure:

$ tree .
├── Makefile
├── include
│   └── common_head.h
├── obj
└── src
    ├── foo.c
    └── main.c

Manual execution:

$ gcc -o ./obj/foo.o  -c ./src/foo.c  -I ./include  # Build Object #
$ gcc -o ./obj/main.o -c ./src/main.c -I ./include
$ gcc -o exe ./obj/foo.o ./obj/main.o               # Build Executable #

---

Makefile to simulate the above

C_FLAGS := -g -Wall -Wextra
CC := gcc
RM := rm
LINKFLAGS := -lanylibrary

.PHONY: $(TARGET)
.PHONY: clean

VPATH:= ./src/ ./obj/ ./include/

# Path for .c , .h and .o Files 
SRC_PATH := ./src/
OBJ_PATH := ./obj/
INC_PATH := -I ./include

# Executable Name 
TARGET := exe

# Files to compile
OBJ1 := foo.o \
        main.o

OBJ := $(patsubst %,$(OBJ_PATH)%,$(OBJ1))

# Build .o first
$(OBJ_PATH)%.o: $(SRC_PATH)%.c
                @echo [CC] $<
                @$(CC) $(C_FLAGS) -o $@ -c $< $(INC_PATH)                  

# Build final Binary
$(TARGET):      $(OBJ)
                @echo [INFO] Creating Binary Executable [$(TARGET)]
                @$(CC) -o $@ $^ $(LINKFLAGS)

# Clean all the object files and the binary
clean:   
                @echo "[Cleaning]"
                @$(RM) -rfv $(OBJ_PATH)*
                @$(RM) -rfv $(TARGET)

---

So when you do a Make

$ make -B
[CC] src/foo.c
[CC] src/main.c
[INFO] Creating Binary Executable [exe]

To see a dry-run use make -n

$ make clean ; make -n
g++ -g -Wall -Wextra -o obj/foo.o  -c src/foo.c  -I ./include
g++ -g -Wall -Wextra -o obj/main.o -c src/main.c -I ./include
g++ -o  exe  obj/foo.o obj/main.o -lanylibrary

---

So after building your directory structure should look like this.

$ tree .
├── Makefile
├── exe
├── include
│   └── common_head.h
├── obj
│   ├── foo.o
│   └── main.o
└── src
    ├── foo.c
    └── main.c

So from my previous answer.
You don't have to use any PHONY move and also no objects are recreated unnecessarily.