Makefile 编译问题找不到 *.o 没有这样的文件或目录

Question

I'm trying to make a simple Makefile with files in different subfolders. This is my Makefile

CFLAGS = -g -Wall
IFLAGS = -Iinclude
OPATH = obj/
CPATH = src/

vpath %.h include
vpath %.c src
vpath %.o obj
vpath main bin



main: main.o grille.o io.o jeu.o
    gcc $(CFLAGS) -o main $(OPATH)main.o $(OPATH)grille.o $(OPATH)io.o $(OPATH)jeu.o 
    mv $@ bin/
main.o: main.c grille.h io.h jeu.h
    


grille.o : grille.c grille.h
    

io.o: io.c io.h
    

jeu.o: jeu.c jeu.h
    

%.o : 
    gcc $(CFLAGS) -c $< $(IFLAGS)
    mv $@ $(OPATH)

clean:
    rm obj/* bin/*

I have the files in subfolders called src, obj, and include. I get this error

C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find obj/main.o: No such file or directory
C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find obj/grille.o: No such file or directory
C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find obj/io.o: No such file or directory
C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find obj/jeu.o: No such file or directory
collect2.exe: error: ld returned 1 exit status
make: *** [makefile:15: main] Error 1

ERROR

Any Ideas how to fix this?

Answer 1

Writing output files to a different directory than the input files requires extra setup. You should look at your compile line that make runs. Does it put the object file in the right place? If not then that explains why you get those link errors: the object files don't exist where you told the linker they will be, so it fails.

This rule is not right:

%.o : 
        gcc $(CFLAGS) -c $< $(IFLAGS)
        mv $@ $(OPATH)

Also, you cannot use vpath to search for targets that are built by makefiles. That can't work. vpath can ONLY be used to search for source files (like .c or .h files). So these lines don't do anything and should be removed:

vpath %.o obj
vpath main bin

And these rules are not right: you need to put the object directory here:

grille.o : grille.c grille.h
io.o: io.c io.h
jeu.o: jeu.c jeu.h

You want something like this:

CC = gcc
CFLAGS = -g -Wall
IFLAGS = -Iinclude
OPATH = obj/

vpath %.h include
vpath %.c src

bin/main: obj/main.o obj/grille.o obj/io.o obj/jeu.o
    $(CC) $(CFLAGS) -o $@ $^

main.o: main.c grille.h io.h jeu.h
grille.o : grille.c grille.h
io.o: io.c io.h
jeu.o: jeu.c jeu.h

$(OPATH)%.o : %.c
        $(CC) $(CFLAGS) $(IFLAGS) -c -o $@ $<