Makefile error message custom

Question

I have some problem with a makefile. I just want to test if the compilation on src/launcher.c failed or not. But before that, i just can't convert this bash code:

out=$(gcc -c src/launcher.c -o /obj/launcher.o 2>&1)

To "Makefile code"

in fact, i want to make something like that : Handling gcc warnings and output in a Bash Script but in a makefile

Please, if you have some ideas.

CC      = clang
RM      = rm -f

NAME        = automakefile

CFLAGS      += -Wall -Wextra
CFLAGS      += -O2 -march=native -fomit-frame-pointer

LDFLAGS     +=

OBJS_DIR    = ./obj/
SRCS_DIR    = ./src/

INCLUDES    += -I ./src/include

OBJS_FILES  = launcher.o

OBJS        = $(foreach obj,$(OBJS_FILES),$(OBJS_DIR)$(obj))

all: script $(NAME)

script:
    @if [ ! -d "$(OBJS_DIR)" ]; then    \
        mkdir $(OBJS_DIR);      \
    fi

$(NAME): $(OBJS)
    $(CC) $(CFLAGS) $(OBJS) -o $(NAME) $(LDFLAGS)

$(OBJS_DIR)%.o: $(SRCS_DIR)%.c
    //This line isn't working!
    $(eval TMP=$$(gcc -c src/launcher.c -o obj/launcher.o 2>&1))
    echo $(TMP)

clean:
    $(RM) $(OBJS)

fclean: clean
    $(RM) $(NAME)

re: fclean all

.Phony: all script clean fclean re

Thanks Have a nice day

The "if" is testing the status of the echo, which is always true. — RTLinuxSW, Jun 22 '15 at 12:55
I remove the if for no confusion, because it's not the main problem. I need to convert the bash on the top — user3409642, Jun 22 '15 at 13:08

Chnossos · Answer 1 · 2015-06-22T14:24:59.467

1

Make will automatically stop the compilation process whenever an error occur, but you can do with a message in case of warning or nothing bad happened:

$(OBJS_DIR)%.o: $(SRCS_DIR)%.c
    @$(CC) $(CPPFLAGS) $(CFLAGS) -o $@ -c $< &>output
    @if grep "warning" output >/dev/null ; then echo "$(<F) Warning" ; else echo "$(<F) OK" ; fi
    @$(RM) output

Here you go:

$(OBJS_DIR)%.o: $(SRCS_DIR)%.c
    @if $(CC) $(CPPFLAGS) $(CFLAGS) -o $@ -c $< &>output; then \
        if grep "warning" output >/dev/null; then              \
            echo "$(<F) Warning(s)";                           \
        else                                                   \
            echo "$(<F) OK";                                   \
        fi;                                                    \
    else                                                       \
        echo "$(<F) Error(s)";                                 \
    fi
    @$(RM) output

edited Jun 22 '15 at 14:24

answered Jun 22 '15 at 13:42

Chnossos

9,971
4
28
40

Yes, thanks for you answer. So you think that it's just impossible to do something like in the link above into a makefile? – user3409642 Jun 22 '15 at 13:47
You could get the whole compilation process out of the makefile, which would then call that script instead. – Chnossos Jun 22 '15 at 13:49
@EtanReisner It was a remnant of my previous experiments, it has now been removed. – Chnossos Jun 22 '15 at 13:59
@user3409642 I think I got it now. – Chnossos Jun 22 '15 at 14:25
Yes, i don't like the tmp file. But i ended like this too – user3409642 Jun 22 '15 at 15:24

score 1 · Answer 2 · answered Jun 22 '15 at 13:50

make stops on target failure, you won't get any farther than the compilation that fails so you won't see anything beyond that.

If you are looking to "silence" the compilation a bit (so you don't see the compilation command itself) you could look into using something like my silent make rules makefile (based on the silencing support in recent autotools).

That won't hide output from the compilation commands themselves (warnings, etc.) but for successful/warning-free compilation there shouldn't be much output anyway and for failures/warnings you likely want to see it.

If you do want to do something like in your original link then you need to make sure that you hide the error code return from gcc in an if or similar (and capture it) and then exit with it again at the end of the recipe so that make still stops correctly.

@user3409642 I haven't written any introduction/help for that yet, if you can't figure it out feel free to ask or file an issue or something. — Etan Reisner, Jun 22 '15 at 14:05

score 1 · Answer 3 · answered Jun 22 '15 at 14:20

1

At the end, i used a little trick:

@$(CC) $(CFLAGS) -c $^ -o $@ $(INCLUDES) \
                && echo -e "\033[33;1m=== Compilation $@ \tSUCCEED===\033[0m"\
                || echo -e "\033[1;31m=== Compilation $@ \tFAILED===\033[0m"

answered Jun 22 '15 at 14:20

user3409642

87
8

Makefile error message custom

3 Answers3