How to remove Makefile Dependency on C file - makefile

I have the below Makefile and for some reason it's dependent on a file, ewapi.c. This file executes some SWIG commands and uses the ewapi.i file. I've clear out all the contents of ewapi.c and the Makefile successfully runs. If I remove the ewapi.c file the make file will not complete. The exception stack is below if that helps. Any ideas on how to change the Makefile so its not dependent on ewapi.c?
# BUILD_DIR and DIST_DIR are exported by build.xml
#
CMODE=
SWIG = swig
CC = $(PREFIX)gcc
LD = $(CC)
OBJ_DIR = $(BUILD_DIR)/obj
AUTOGEN_DIR = $(BUILD_DIR)/auto-generated
PACKAGE_DIR = $(AUTOGEN_DIR)/com/sample/jni
PACKAGE = com.sample.jni
INCLUDES = -I$(JAVA_INCLUDE) \
-I$(SAMPLE_SDK_DIR)/include \
-I$(JDK_HOME)/include
LIB_INCLUDES = -L$(SAMPLE_SDK_DIR)/lib
LIBS = /lib/libssl.so.4 \
/lib/libcrypto.so.4 \
-lSampleApi \
-lm
DIRS = $(PACKAGE_DIR) $(DIST_DIR) $(OBJ_DIR) $(AUTOGEN_DIR)
CFLAGS = $(CMODE) -Wall -fpic $(INCLUDES) -O0 -g3
SFLAGS = -java $(INCLUDES) -package $(PACKAGE) -outdir $(PACKAGE_DIR)
LDFLAGS = -shared $(LIB_INCLUDES) $(LIBS)
OBJECTS = $(OBJ_DIR)/ewapi_wrap.o $(OBJ_DIR)/ewapi.o
TARGET = $(DIST_DIR)/libSample.so
all: $(DIRS) $(TARGET)
%_wrap.c: %.i
$(SWIG) $(SFLAGS) $<
$(OBJ_DIR)/%.o: %.c
$(CC) $(CFLAGS) -c $< -o $#
$(TARGET): $(OBJECTS)
$(LD) $(OBJECTS) $(LDFLAGS) -o $#
$(DIRS):
mkdir -p $#
clean:
rm -rf $(TARGET) $(PACKAGE_DIR)/* $(TARGET) $(AUTOGEN_DIR) $(OBJ_DIR)
Exception Stack (when I remove ewapi.c):
[exec] rm ewapi_wrap.c
[exec] make-3.79.1-p7: *** No rule to make target `/test/build/obj/ewapi.o', needed by `/test/dist/libSample.so'. Stop.

The macros OBJECTS includes $(OBJ_DIR)/ewapi.o; the rule for $(TARGET) says it depends on $(OBJECTS); and the rule for all says it depends on $(TARGET). So, there needs to be a way to create ewapi.o from something - and in the absence of ewapi.c, there is no way to build ewapi.o, hence the complaint you get.
Possible fixes:
Replace ewapi.c.
Remove ewapi.o from the macro $(OBJECTS).

Remove $(OBJ_DIR)/ewapi.o from OBJECTS.

Related

Makefile: Unable to add .h files from folder using a .mk file

I'm trying to link a .h file from a folder into a Makefile using a .mk file. Folder with .h file (include) is in the same folder as Makefile.
When I run from terminal: make memory.o or make memory.o PLATFORM=MSP432 I get the following error
make: *** No rule to make target '-I./include', needed by 'memory.o'. Stop.
My .mk folder looks like this:
# Add your Source files to this variable
SOURCES = \
./main.c \
./memory.c
# Add your include paths to this variable
INCLUDES =-I./include
My Make file looks like this:
include sources.mk
# Platform Overrides
PLATFORM =
# Architectures Specific Flags
LINKER_FILE = msp432p401r.lds
CPU = cortex-m0plus
ARCH = thumb
SPECS = nosys.specs
# Compiler Flags and Defines
CC = arm-none-eabi-gcc
LD = arm-none-eabi-ld
TARGET= c1m2
LDFLAGS = -Wl, -Map=$(TARGET).map -T $(LINKER_FILE)
CFLAGS = -Wall -Werror -g -O0 -std=c99 -mcpu=$(CPU) -m$(ARCH) --specs=$(SPECS)
CPPFLAGs =
ifeq ($(PLATFORM),MSP)
CPU=cortex-m4
CC=arm-none-eabi-gcc
endif
ifeq ($(PLATFORM),HOST)
CC=gcc
endif
OBJS = $(SOURCES:.c=.o)
%.o : %.c $(INCLUDES)
$(CC) -c $< $(CFLAGS) -o $#
.PHONY: build
build: all
.PHONY: all
all: $(TARGET).out
$(TARGET).out: $(OBJS) $(INCLUDES)
$(CC) $(OBJS) $(CFLAGS) $(LDFLAGS) -o $#
.PHONY: clean
clean:
rm -f $(OBJS) $(TARGET).out $(TARGET).map
Can anybody help?
You shouldn't put $(INCLUDES) as a prerequisite of your .o file. This is not right:
%.o : %.c $(INCLUDES)
$(CC) -c $< $(CFLAGS) -o $#
INCLUDES contains options that need to be passed to the compiler (-I...). Prerequisites of targets need to be files that are used during the build. I suppose you want this:
%.o : %.c
$(CC) -c $< $(CFLAGS) $(INCLUDES) -o $#

No rule to make target *, needed by *

I can't get what's wrong with my makefile:
DIST_PATH = ../dist/libs
BUILD_PATH = ../build
MKDIR_P = mkdir -p
.PHONY: all
SHELL = /bin/sh
CC = gcc
FLAGS = -std=gnu99
CFLAGS = -fPIC -pedantic -Wall -Werror
LDFLAGS = -shared
LOG_SRCS = $(shell echo log/*.c)
LOG_HEADERS = $(shell echo log/*.h)
LOG_OBJS = $(addprefix $(BUILD_PATH)/, $(notdir $(LOG_SRCS:.c=.o)))
LOG_TARGET = $(DIST_PATH)/liblog.so
all: dirs $(LOG_TARGET)
dirs :
$(MKDIR_P) $(DIST_PATH)
$(MKDIR_P) $(BUILD_PATH)
$(LOG_TARGET) : $(LOG_OBJS)
$(CC) $(FLAGS) $(CFLAGS) -o $# $(LDFLAGS)
I need to build a shared library from sources in log/ folder to ../dist/libs and put obj file in ../build but I am getting the error:
make: *** No rule to make target '../build/log.o', needed by '../dist/libs/liblog.so'. Stop.
P.S. I know there are many similar questions but I couldn't get from these questions how to resolve my problem.
The problem is that the source and object files are supposed to be placed in different directories, and there's no implicit rule for that.
You need to add a rule for how to translate a source file to an object file:
$(BUILD_PATH)/%.o: log/%.c
Now make knows how to create the object files from the source files.
There's another problem though:
$(LOG_TARGET) : $(LOG_OBJS)
$(CC) $(FLAGS) $(CFLAGS) -o $# $(LDFLAGS)
The command doesn't list any input files, you need to add all the object files to be linked:
$(LOG_TARGET) : $(LOG_OBJS)
$(CC) $(FLAGS) $(CFLAGS) -o $# $^ $(LDFLAGS)
# ^^
# List of all "prerequisites" (object files) to be linked

gcc cannot specify -o with -c or -S with Multiple files

Whenever I am trying to build something like this in my Makefile -
gcc -o main.o -IStarterWare_Files -c main.c StarterWare_Files/test.h StarterWare_Files/add.h
It throws me error that gcc: cannot specify -o with -c or -S with multiple files. Basically I want my makefile to build the target again if I change for example some macro in one of my header files. My current Makefile is -
EXE = nextgenrsm
CC = gcc
LIBS = StarterWare_Files/
CPPFLAGS = _IStarterWare_Files/
MAIN_OBS = $(patsubst %.c,%.o,$(wildcard *.c))
LIB_OBS = $(patsubst %.c,%.o,$(wildcard StarterWare_Files/*.c))
all: $(EXE)
$(EXE): $(MAIN_OBS) $(LIB_OBS)
$(CC) -o $# $(LDFLAGS) $(MAIN_OBS) $(LIB_OBS) $(LDLIBS)
%.o: %.c
$(CC) -o $# -MD -MP $(CPPFLAGS) $(CFLAGS) -c $^
ALL_DEPS = $(patsubst %.o,%.d,$(MAIN_OBS), $(LIB_OBS))
-include $(ALL_DEPS)
clean:
rm -f $(LIB_OBS) $(EXE) $(MAIN_OBS) $(ALL_DEPS)
.PHONY: all clean
I can't figure out what changes to make to build my executable again if one of the header files is modified. I don't want to do make clean and make again.
The way the automake system handles this is to not use %.o: %.c but instead list the C file and all of the headers in the C file.
So for example:
main.o: main.c StarterWare_Files/test.h StarterWare_Files/add.h
$(CC) -o $# -MD -MP $(CPPFLAGS) $(CFLAGS) -c $^
See makedepends for a tool that will read C files and figure out the make dependencies.

Why Make doesn't recognize my variable?

I have a short Make script, which works if I put the Build directory in as a string manually myself instead of as a variable:
CC = gcc
CFLAGS = -O2 -g -Wall -fmessage-length=0
LDFLAGS =
SRCDIR = Src
BUILDDIR = Build
SRCS = $(SRCDIR)/Main.c
OBJS = $(SRCS:.c=.o)
LIBS =
TARGET = HelloWorld
all: dir $(SRC) Build/$(TARGET)
dir:
mkdir -p $(BUILDDIR)
Build/$(TARGET): $(OBJS)
$(CC) $(LDFLAGS) $(OBJS) -o $#
$(SRCDIR).c.o:
$(CC) $(CFLAGS) $< -o $#
clean:
rm -f $(OBJS) $(TARGET)
It stops working with the error message:
make: *** No rule to make target `/HelloWorld', needed by `all'. Stop.
when I replace the line:
all: dir $(SRC) Build/$(TARGET)
with:
all: dir $(SRC) $(BUILDDIR)/$(TARGET)
Why is Make not substituting the $(BUILDDIR) clause with Build?
In your code there is a space after Build
BUILDDIR = Build

Makefile does not work properly

I've this folder structure
project
|_src
| |_test
| |_main.cpp
|_Makefile
This is my makefile (trying to adapt from this link):
CC = g++
RM = rm
WFLAGS = -c -Wall -W
LDFLAGS =
SRCTESTD = src/test
EXECUTABLE = test
OBJD = .obj
DEPD = .dep
SRCSTEST = $(SRCTESTD)/main.cpp
OBJECTSTEST = $(patsubst %.cpp, $(OBJD)/test/%.o, $(notdir $(SRCSTEST)))
DEPDSTEST = $(patsubst %.cpp, $(DEPD)/test/%.d, $(notdir $(SRCSTEST)))
all: $(SRCSTEST) $(EXECUTABLE)
$(EXECUTABLE): $(OBJECTSTEST)
$(CC) $(LDFLAGS) $(OBJECTSTEST) -o $#
.cpp.o:
$(CC) $(WFLAGS) $< -o $#
It does not work, and I've this error
make: *** No rule to make target `.obj/test/main.o', needed by `test'. Stop.
What I'm doing wrong? Sorry for trivial question, but I'm a make newbie.
The link shows outdated methods, such as suffix rules. Making dependencies can also be done during compilation by gcc/g++.
As for the rest, here is it :
EXE := test
SRCDIR := src
OBJDIR := .obj
SRC := $(shell find $(SRCDIR) -name "*.cpp")
OBJ := $(SRC:$(SRCDIR)/%.cpp=$(OBJDIR)/%.o)
DEP := $(OBJ:.o=.d)
LDLIBS := # -l flags
LDFLAGS := # -L flags
CPPFLAGS := -MMD -MP # -I flags also
CXXFLAGS := -W -Wall # no -c flag here
.PHONY: all clean fclean re
all: $(EXE)
clean:
$(RM) -r $(OBJDIR)
fclean: clean
$(RM) $(EXE)
re: fclean all
-include $(DEP)
$(EXE): $(OBJ)
$(CXX) $(LDFLAGS) $^ $(LDLIBS) -o $#
$(OBJDIR)/%.o: $(SRCDIR)/%.cpp
#mkdir -p $(#D)
$(CXX) $(CPPFLAGS) $(CXXFLAGS) -o $# -c $<
No redefinition of internally defined variables, no suffix rules, correct linking step and dependencies generation.
Update: To avoid calling mkdir for every source file, one should use order-only prerequisites and the special target .SECONDEXPANSION.
Change this block:
$(OBJDIR)/%.o: $(SRCDIR)/%.cpp
#mkdir -p $(#D)
$(CXX) $(CPPFLAGS) $(CXXFLAGS) -o $# -c $<
To this:
.SECONDEXPANSION:
$(OBJDIR)/%.o: $(SRCDIR)/%.cpp | $$(#D)/
$(CXX) $(CPPFLAGS) $(CXXFLAGS) -o $# -c $<
%/:
mkdir $*
The error means make can't find a correct rule to build your object files. Your tree structure lacks some informations: only one file ? Where are the others ? Anyway, here are some hints:
In the last two lines, you are using an obsolete feature of make: suffix rules. I suggest you switch to a pattern rule, which is functionaly equivalent.
Say something like:
%.o: %.cpp
$(CXX) $(CXXFLAGS) $< -o $#
Another thing (that shouldn't be a problem here): you are using the variable CC which is internally defined as the default C compiler. It's okay because you redefine it, but as your sources seem to be C++ files, why not use the variable CXX, that is internally defined as the C++ compiler ?
Lastly, to make sure your set of files are correctly defined, you can print them with a dummy show target, see here.
show:
#echo "OBJECTSTEST=$(OBJECTSTEST)"
...

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