Makefile pattern to compile all source files to executables - makefile

I want my makefile to identify and build every source file in the directory.
Both .f files and their executables exists in the current directory. All source files are short, independent pieces (no linking to each other). I want executables to be named the same as the source files sans .f (foo.f -> foo)
The following does not work:
FC=gfortran
% :: %.f
${FC} -Wall $< -o $#
When I run Make I get
make: *** No targets. Stop.
How can I get make to do what I want?

The following makefile does what I want:
FC=gfortran
FFLAGS=-Wall
SRC = $(wildcard *.f)
EXE = $(SRC:.f=)
all : $(EXE)

Related

Makefile to generate a binary file for each source file

I have the following structure in my project.
/
src/
bin/
Makefile
In src directory there will be multiple src files (each has a main function). I need to write makefile such that when I run
make program1
It should search for program1.c in src folder and compile the executable as program1* in bin folder.
I have came across this question How can Makefile use separate directories for source code and binaries?
But, it seems that I need to manually enter all program names into PROG variable.
I just need to supply binary name with make and it should do the compilation for that respective src file?
Okay, after a bit of experimentation with my Makefile. I finally got the solution for my problem.
Current Build System
CC = gcc
CFLAGS = -g -Wall
SRC = ./src/
BIN = ./bin/
%: $(SRC)%.c
$(CC) $(CFLAGS) $< -o $(BIN)$#
.PHONY: clean
clean:
rm $(BIN)*

makefile .mod compilation rule

I'm modifying makefile of a code. After compiling, I see that some *.mod files are generated. looking online, I figured out they are module files, but I don't see a compilation rule for them. I'm trying to change the directory in which these files are generated. I can change the rule for object files, but I can't find the rule that generates *.mod files.
Looking at the makefile, can someone advise me if a line in this file generates them or how to change their directory. Here is the makefile:
# GNU Makefile
# Paths
SDIR=./solver
ODIR=./obj
_CASE=./WorkCases/problem
CASE=$(SDIR)/$(_CASE)
TOP = .
FC = ifort
FFLAGS = -fpp -O1 -DPTR_INTEGER8 -warn nousage
# Define rule to make .f90
$(ODIR)/%.o : $(SDIR)/%.f90
$(FC) -c $(FFLAGS) $< -o $#
# set executable name
EXEC = $(dir ${CASE})/$(basename $(notdir ${CASE})).out
# shared global variables
_SHARED_OBJ = shared_modules.o main_vars.o debug_vars.o
SHARED_OBJ = $(patsubst %,$(ODIR)/%,$(_SHARED_OBJ))
OBJ = ${_SHARED_OBJ} $(_CASE).PARAMS.o
OBJ = $(patsubst %,$(SDIR)/%,$(_OBJ))
MAIN_OBJ = $(ODIR)/main.o
main : ${SHARED_OBJ} $(OBJ) $(MAIN_OBJ)
$(FC) ${FFLAGS} $(OBJ) $(MAIN_OBJ) -o $(EXEC) -lstdc++ -shared-intel
You can specify the destination directory for the .mod files by using the -module compiler option.
-module <directory>
See the ifort documentation here:
You can use the module path compiler option to specify the directory
in which to create the module files. If you do not use this option,
module files are created in the current directory.

How to create a makefile that will place object code in different folder

I am very new to Makefile. I had build the following makefile(Which don't work).I wan't put genarated object codes in differnt folder(the folder is in current directory).
$ ls
main.cpp Makefile object_code Time.cpp Time_.h
how can I do this ??
VER = Debug
CC = g++
OBJECTFIELS = ./object_code/main.o ./object_code/Time.o
../$(VER)/main: $(OBJECTFIELS)
$(CC) $(OBJECTFIELS) -o $#
$(OBJECTFIELS): Time_.h
./object_code/main.o: main.cpp
./object_code/Time.o: Time.cpp
clean:
rm $(OBJECTFIELS) main
this is error.
$ make
g++ ./object_code/main.o ./object_code/Time.o -o ../Debug/main
g++: error: ./object_code/main.o: No such file or directory
g++: error: ./object_code/Time.o: No such file or directory
g++: fatal error: no input files
compilation terminated.
Makefile:8: recipe for target '../Debug/main' failed
make: *** [../Debug/main] Error 1
please this is last question.
I don't see how you can possibly get that output given the makefile you've posted here.
Either the object files already exist in which case the link will succeed rather than printing that error.
Or the object files don't exist in which case make will complain because it doesn't know how to make them. There must be some difference between the makefile you're using and the one you've posted here.
In any event, make knows how to build a file foo.o from a file foo.cpp for any string foo. There's a built-in rule that tells it how to do that.
But, make doesn't know how to build a file ./object_code/foo.o from a file foo.cpp, regardless of foo. There's no built-in rule that tells make how to build object files in some random other directory. If you want make to do that, you'll have to tell it how. You should remove the lines:
./object_code/main.o: main.cpp
./object_code/Time.o: Time.cpp
and replace them with a pattern rule describing how to build object files into the object_code directory (I'm using CXX as the compiler variable here: by convention CC is the C compiler and CXX is the C++ compiler, and you should always stick with convention unless there's a good reason not to):
VER = Debug
CXX = g++
OBJECTFIELS = ./object_code/main.o ./object_code/Time.o
../$(VER)/main: $(OBJECTFIELS)
$(CXX) $(OBJECTFIELS) -o $#
$(OBJECTFIELS): Time_.h
./object_code/%.o : %.cpp
$(CXX) -c -o $# $<
clean:
rm $(OBJECTFIELS) main

How to compile files that reside in different directory in Makefile?

I have seen this questions asked before but was not able to decipher those answers.
Lets say I reside in working directory, lets call it proj and this proj directory contains src folder which contains all the *.cpp files. I want to compile those file staying on the proj directory because in future I will be creating bin directory and placing the *.o and binary in bin.
So my proj directory currently contains : Makefile and src
What I have done so far is :
SOURCE = src
# This gives the path to the proj directory
CURRENT_DIR = $(shell pwd)
# This gives list of all the *.cpp files
SRC = $(shell cd $(SOURCE) && echo *.cpp)
# Here all the name of the files stored in SRC are converted from *.cpp to *.o
OBJS = $(SRC:.cpp=.o)
.PHONY: all
all: $(TARGE)
# use the content of SRC to compile
$(TARGET): $(OBJS)
$(info $(OBJS))
$(OBJS): $(SRC)
$(CC) $(FLAGS) -c $?
When I try to run the make command it says
make: *** No rule to make target 'xxx.cpp', needed by 'xxx.o'. Stop
Now I know what it is trying to say. It gives error because although it knows the name of the file, since the file is not in the current directory makefile does not know about src folder and hence have no clue about the *.cpp files.
So my question is: Is there any macros or trick to use in makefile to make sure makefile see the xxx.cpp in src folder while staying in the current directory( I don't want to specify the folder by hand here)?

Makefile is always not up to date even without any changes

I have a directory with two folders, src and bin with the makefile at root directory. This makefile keeps compiling (not up to date) even without changes. Am I missing something with this makefile?
all:
make a b
a: ./src/a.cpp
g++ -o ./bin/a ./src/a.cpp
b: ./src/b.cpp
g++ -o ./bin/b ./src/b.cpp
Your rules claim to create the files a and b, but they don't: They create bin/a and bin/b.
So when make checks your rules, it always finds that a and b don't exist and tries to create them by executing their associated commands.
Possible fix:
.PHONY: all
all: bin/a bin/b
bin/a: src/a.cpp
g++ -o bin/a src/a.cpp
bin/b: src/b.cpp
g++ -o bin/b src/b.cpp
On .PHONY: https://www.gnu.org/software/make/manual/html_node/Phony-Targets.html#Phony-Targets

Resources