makefile makes weird error - c

So I wrote a program to calculate Caesar cipher but I think it's not really matter - what matter is that when I'm trying to do make the compiler or who checks the syntax of my makefile is throw an error says :
make: *** No rule to make target 'clean.', needed by 'PHONY'. Stop.
In my directory I have 5 files:
main.c
ceasar.c
ceasar.h
parser.c
parser.h
and the makefile looks like:
PHONY : all clean.
CFLAGS = -c -g -Wall
CXXFLAGS = -o
CC = gcc
OBJECTS = main.o ceasar.o parser.o
EXTRA_SRCS = ceasear.h parser.h
all : ex1
ex1 : $(objects)
$(CC) $(CXXFLAGS) ex1 $(objects)
%.o : %.c $(wildcard $(EXTRA_SRCS))
$(CC) $(CFLAGS) $<
clean:
rm *.o
The makefile should clean the objects files when typed make clean
and the line $(wildcard $(EXTRA_SRCS)) should checks if the c file has header file(parser and caeser, not main).
I'm using ubuntu 15.10 and please help me :)

It's possible to specify fictitious target that has as purpose to execute a sequence of operations. These targets do not specify any dependency and must not appear as the first rule, to be carried out only if they are passed as arguments to make command explicitly. Fictitious target is not a file (the file does not exist) it is used to initiate the execution of the command in each case.
CFLAGS = -c -g -Wall
CXXFLAGS = -o
CC = gcc
OBJECTS = main.o ceasar.o parser.o
EXTRA_SRCS = ceasear.h parser.h
all : ex1
ex1 : $(objects)
$(CC) $(CXXFLAGS) ex1 $(objects)
%.o : %.c $(wildcard $(EXTRA_SRCS))
$(CC) $(CFLAGS) $<
.PHONY: clean
clean: rm *.o
Be careful because the fictitious target may be masked by existing files: if accidentally in the directory it creates a file called the same name of the fictitious target then, as the target has no dependencies, and the file already exists, that file does not need to be updated and then the command list will never be executed.

Related

How to run and execute a makefile C

I'm trying to make a Makefile for my program. It is so difficult because i've read a lot of guide but none is clear. I have 3 files : main.c , library.c , library.h . Main.c and library.c depend on library.h . The structure of my directory project is formed by :
MyProject directory -> Build directory and Exercise1 directory -> all of my files . In compiler I wrote make and it compiled ; then when I write make execute command, it gives me this error:
cd ../build; ./test
Error: No such file or directory
makefile:23: recipe for target 'execute' failed
make: *** [execute] Error 1
MAKEFILE
CC=gcc
CFLAGS=-Wall
ODIR=../build
DIR = build
.PHONY: all
all: main.o library.o test
$(ODIR)/%.o: %.c $(DEPS)
$(CC) -std=c99 -c -o $# $< $(CFLAGS)
library.o: library.c library.h
$(CC) -std=c99 -c -o $(ODIR)/$# $< $(CFLAGS)
main.o: main.c library.h
$(CC) -std=c99 -c -o $(ODIR)/$# $< $(CFLAGS)
test: $(ODIR)/library.o $(ODIR)/main.o
$(CC) -std=c99 -o $(ODIR)/$# $^ $(CFLAGS)
execute:
cd $(ODIR); ./test
clean:
rm -f $(ODIR)/*.o
These lines:
execute:
cd $(ODIR); ./test
tell make that, when you give the command make execute, it should change the working directory to $(ODIR) and then execute ./test, which means to execute the file test in the current working directory. However, there is no file test in the $(ODIR) directory because you have not built it yet.
You can make that file by executing make test, but that is a bad way to do it. It is better to tell make that the execute target depends on $(ODIR)/test:
execute: $(ODIR)/test
cd $(ODIR); ./test
Then we should change the rule for test to $(ODIR)/test:
$(ODIR)/test: $(ODIR)/library.o $(ODIR)/main.o
$(CC) -std=c99 -o $(ODIR)/$# $^ $(CFLAGS)
Next, delete the rule for all and the .PHONY rule. A rule for all should be used when a makefile can make several different final targets, like ProgramA, ProgramB, and ProgramC, and you want one target that makes all of them. It should not be used to make all of the intermediate object files for a target. The intermediate files should arise out of the rules for building a final target.
Then delete the rules for library.o and main.o. Those are names for files in the current directory, but you are building in $(ODIR). We will let the pattern rule for $(ODIR)/%.o build those.
But we need to fix the pattern rule. It uses DEPS, but that is not defined. Add a line above that says what all the object files depend on:
DEPS=library.h
Nothing in the makefile uses DIR, so delete the line DIR = build.
Finally, you might want to put the execute target first, so that it is the default. Then your makefile is:
CC=gcc
CFLAGS=-Wall
ODIR=../build
DEPS=library.h
execute: $(ODIR)/test
cd $(ODIR); ./test
$(ODIR)/%.o: %.c $(DEPS)
$(CC) -std=c99 -c -o $# $< $(CFLAGS)
$(ODIR)/test: $(ODIR)/library.o $(ODIR)/main.o
$(CC) -std=c99 -o $(ODIR)/$# $^ $(CFLAGS)
clean:
rm -f $(ODIR)/*.o
You might also change the command for clean to remove test:
rm -f $(ODIR)/*.o $(ODIR)/test

Compile multiple .c files with makefile

I would like to compile multiple .c files at once using a makefile.
I already made this:
CC= gcc
CPPFLAGS = -I.
CFLAGS = -W -Wall -ansi -pedantic
TARGET = test
RM = rm
OBJECTS = xxx.o yyy.o zzz.o
SOURCES = $(OBJECTS:.o =.c)
.PHONY: all clean
all: $(TAREGT)
clean:
$(RM) $(TARGET) $(OBJECTS)
$(TAREGT) : $(OBJECTS)
$(CC) $^ -o $#
$(OBJECTS) : $(SOURCES)
$(CC) $(CFLAGS) $(CPPFLAGS) -c $^
I have no Idea why this does not work("nothing to be done for "all"). Someone has an idea?
This line is creating a circular dependency:
SOURCES = $(OBJECTS:.o =.c)
Try replacing it with this:
SOURCES = $(patsubst %.o,%.c,$(OBJECTS))
You forgot -o $# in your 'sources to objects' rule. Thus it doesn't create anything.
You have also spelling error - your $(TARGET) is 'test', but your 'all' rule depends on $(TAREGT) which is empty. You are also using $(TAREGT) as input to compile 'test'.
You don't need to specify $(SOURCES) or "sources to objects" rule - implicit rules will do the trick.
In fact your "sources to objects" rule is incorrect - it says that each object depends on all sources. If you want each object to depend on one source you should use either suffix rule, pattern rule or static pattern rule. Or just implicit rule.
$(OBJECTS) : $(SOURCES)
The above tells Make that every .o file depends on all sources, i.e. if you change one of your .c files Make will recompile all .o files. Not something what you really want, I guess. I'd rework this rule as follows:
$(foreach s,$(SOURCES),$(eval $(filter %$(basename $(notdir $s)).o,$(OBJECTS)): $s))
This will iterate every source in SOURCES, find corresponding .o file in OBJECTS and create correct rule: <obj>: <source>. It is that complicated to work in case of more complex mapping between source and object files. Say, when building object files in separate directory.
This cryptic code will work even for the following weird source to object file mapping:
SOURCES := a.cpp boo/b.c c.C
OBJECTS := foo/a.o bar/b.o c.o
$(foreach s,$(SOURCES),$(eval $(filter %$(basename $(notdir $s)).o,$(OBJECTS)): $s))
It will generate the following rules:
foo/a.o: a.cpp
bar/b.o: boo/b.c
c.o: c.C
Thank you guys for you help, it is working now
I just added some rules:
CC= gcc
CPPFLAGS = -I.
CFLAGS = -W -Wall -ansi -pedantic
TARGET = test
RM = rm
SOURCES = xxx.c yyy.c zzz.c
OBJECTS = $(SOURCES:.c=.o)
.PHONY: all clean
all: $(TARGET)
clean:
$(RM) $(TARGET) $(OBJECTS)
$(TARGET) : $(OBJECTS)
$(CC) $^ -o $#
%.o: %.c
$(CC) $(CFLAGS) $(CPPFLAGS) -c $<

libgcrypt-config --libs: no such file or directory

I'm using gcrypt, but my compiler seems to unable to find it. Here is my makefile. function.c is a function source file containing functions I defined; I also wrote a header file miao.h with function declaration, and gcrypt.h is included in it. main.c is a source file including miao.h. When I do make: .Could anyone help me? This bothers me so long.
CC = gcc
CFLAGS = 'libgcrypt-config --cflags'
LIBS = 'libgcrypt-config --libs'
OBJS = function.o main.o main
all: $(OBJS)
function.o: function.c
$(CC) -c function.c $(CFLAGS)
main.o: main.c
$(CC) -c main.c $(CFLAGS)
main: main.o function.o
$(CC) -o main main.o function.o $(LIBS)
clean:
rm $(OBJS)
the makefile should be written more like the following:
caveat: I was unable to test the makefile as I do not have libgcrypt-config available.
Per the web site: https://gnupg.org/documentation/manuals/gcrypt/Building-sources.html the libgcrypt-config is an executable so should be surrounded by back-ticks, not single quotes so it will be executed in the current shell.
(back ticks on stackoverflow will result in emphasised text but should still be visible as to where they should be placed.)
Note: where I have placed <tab> your actual makefile needs to have a tab character
Note: targets, like all and clean do not produce a file with the same name, so early in the file there needs to be the statement: .PHONY: all clean
when defining a macro, use := rather than = so the macro is only evaluated once.
Any calls to shell functions should be incorporated via a macro, so it is easy to make a change. In general it is best to include the path to the shell function: I wrote this on Linux, your path may be different. Specifying the actual path becomes very important when cross compiling or there are duplicate names visible via the $PATH statement (as can easily be the case with gcc)
Note: the actual libgcrypt-config executable must be in visible via your $PATH environment variable.
Note: all the individual compile statements could be reduced to the following two lines: (and nothing else needed for the compiles)
%.o: %.c
<tab>$(CC) -c $< -o $# -I. $(CFLAGS)
Note: do not place the contents of a rule where the dependencies is expected. This error was noted in the clean: target
the proposed makefile follows:
CC := /usr/bin/gcc
RM := /usr/bin/rm
CFLAGS := `libgcrypt-config --cflags`
LIBS := `libgcrypt-config --libs`
OBJS := function.o main.o main
TARGET := main
.PHONY: all clean
all: $(TARGET)
function.o: function.c
<tab>$(CC) -c function.c $(CFLAGS) -o function.o -I.
main.o: main.c
<tab>$(CC) -c main.c $(CFLAGS) -o main.o -I.
$(TARGET): $(OBJS)
<tab>$(CC) -o $(TARGET) $(OBJS) $(LIBS)
clean:
<tab>$(RM) -f $(OBJS)

Handling #include <folder/file.h> in C with makefiles

I am in the process of porting some code that was developed in the codeblocks IDE. I am transferring it to a Linux server where I can only use the command line to compile the code. The code is quite large (maybe 100 files) and I need to update the include commands in many files. For when I try to compile it errors on for instance: #include <gsl/gsl_math.h> with a file cannot be found error. I am assuming it cannot be found because the location of the gsl folder was declared in one of the search directory field options in the IDE. I could go through each file an update to the correct path, but is there a better way of doing this for use with a makefile?
Thanks!
EDIT Makefile In Question
# -c : do not link, just create object file
# -o : output file name
CFLAGS += -c -O2 -I../ctraj -I../cspice/include -I../SGP4 -I../cconj -I../GSL-1.13/include
LIBS = -L../ctraj -lctraj -L../cspice/lib -lcspice -L../SGP4 -lsgp4 -L../cconj -lcconj -L./ -lgsl-0 -lgslcblas-0 -lm
DEPS = light.h ../ctraj/ctraj.h ../cconj/cconj.h
OBJ = light.o tle.o propagator.o orbitfit.o conjunction.o light_displacement.o forces_LF.o
OUT = light.exe
%.o: %.c $(DEPS)
gcc -o $# $< $(CFLAGS)
light: $(OBJ)
cd ../ctraj/; make
gcc -o $(OUT) $(OBJ) $(LIBS)
clean:
rm *.o $(OUT)
Edit 2
Folder Structure
light->(GSL-1.13, Light, cconj, ctraj)
the makefile is inside the Light folder.
Error Message
cd ../ctraj/; make
make[1]: Entering directory `/light/ctraj'
gcc -o forces.o forces.c -c -Wall -Wno-maybe-uninitialized -Wno-unused-but-set-variable -O2 -I../cspice/include -Inrlmsise
In file included from ../Light/../cconj/cconj.h:12:0,
from ../Light/light.h:13,
from forces.c:3:
../Light/../cconj/../GSL-1.13/include/gsl/gsl_blas.h:26:28: fatal error: gsl/gsl_vector.h: No such file or directory
compilation terminated.
make[1]: *** [forces.o] Error 1
make[1]: Leaving directory /light/ctraj'
make: *** [light] Error 2
EDIT 3
Second makefile in cconj
# -c : do not link, just create object file
# -o : output file name
#-L../cconj -lcconj
CFLAGS += -c -O2 -I./ -I../GSL-1.13/include
LIBS = -L./ -lgsl-0 -lgslcblas-0 -lm
INC= -I../GSL-1.13/include
DEPS = cconj.h
OBJ = cconj_util.o ellipse_intersect.o collision_prob_real.o rcs2size.o
OUT = libcconj.a
%.o: %.c $(DEPS)
gcc -o $# $< $(CFLAGS)
cconj: $(OBJ)
ar rcs $(OUT) $(OBJ)
clean:
rm *.o $(OUT)
Try adding this line to your makefile, and tell us if it works:
CFLAGS += -I../GSL-1.13/include
In order to compile source code and produce object files, Make must use a rule. (If you don't put such a rule in the makefile, Make has a default rule for that purpose.) It looks something like this:
%.o: %.c
$(CC) $(CPPFLAGS) $(CFLAGS) -c $< -o $#
Without digging too deeply into how that works, we can say that CFLAGS is a list of arguments to be passed to the compiler. When we add -I../GSL-1.13/include, we tell the compiler "if you want to #include something and can't find it elsewhere, look in ../GSL-1.13/include".
If this approach doesn't work, then there's probably a rule in the makefile we must find and alter.
EDIT:
The problem isn't in this makefile (which already contains a reference to GSL-1.13/include). In this command:
cd ../ctraj/; make
this makefile launches a second Make process, which uses the Makefile in light/cconj/. According to the compiler output (gcc -o forces.o ...), that makefile does not include the reference. So try adding the same line there, and if that doesn't work, post that makefile and we'll keep looking.
Use -I option of gcc to specify where to look for includes.

I need some assistance with Makefile in my project

I'm trying to make a Makefile but I'm having some problems
first I have
2 source files: ~/main.c ~/lib/library.c
1 header file: ~/include/library.h
main.c and library.c both share the same header file library.h
# Compiler options
CC = gcc
INC = -I../include
CFLAGS = -Wall -g -c $(INC)
LIB = -L../lib
LFLAGS = -Wall -g $(LIB)
# Dependencies
LIBS = -libmylib
OBJS = main.o
SRCS = $(OBJS:.o=.c)
EXEC = a.out
# Other rules
RM = rm -rf
TAGS = tags
BAK = Makefile.bak
all: $(EXEC)
#echo ------------------------ Compile Complete ----------------------------
.PHONY: clean depend
$(EXEC): $(OBJS)
$(CC) $(LFLAGS) -o $# $^ $(LIBS)
.c.o:
$(CC) $(INC) -M $^
$(CC) $(CFLAGS) -o $# $<
clean:
$(RM) *.o *~ $(EXEC) $(TAGS) $(BAK)
depend: $(SRCS)
makedepend $(INC) $^
it keeps saying that I it can't make a rule out of library.o
plus I have another question
I acknowledge the fact that when Makefile comes in to action after calling 'make',
and subsequently go to the line .c.o or %c: %o(in GNU enhanced version) and make
.o files. but why doesn't it also call clean and depend automatically?
I've edited some things from the previous version of Makefile
this time, (well pretty similar to the previous problem) even though I
clarified the library path(-I../lib),
the Makefile cannot find the archive file (which I created as libmylib.a in ../lib dir)
now it's driving me crazy
but why doesn't it also call clean and depend automatically?
Because make only builds the target you tell it. If you don't specify one, the first target is built, which in many cases, such as yours, is the 'all' target.

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