Let's consider this files structure:
/project
+ Makefile
+ projectA
| + Makefile
| + foo.c
| + bar.c
| + ...
|
+ projectB
+ Makefile
+ oak.c
+ ...
How can I quickly check if a submake is up to date?
In my main make I have:
all:
make -C projectA
And in the submakefile
all: a.txt b.txt
%.txt:%.xtx
cp $< $#
The problem with this solution is that I will always call the submake whatever it has nothing to do. I want to avoid it.
The ugly solution I've found is to create a make rule in my submakefile to echo all the files that are depending on the main target. Then I can call the submake with a shell command:
listfiles=$(shell make -C projectA listfiles)
all: $(listfiles)
make -C projectA
EDIT
A better approach would be to have a shell script in each sub-projects that returns the list of all the project's dependencies. For instance:
projectc/listdep.sh:
#!/usr/bin/bash
find . -iname *.[ch]
Then I can use this script in the parent make:
projectc/a.out: $(shell projectc/listdep.sh)
make -C $(dir $#)
In this way, the parent make won't call the recipe if projectc/a.out exists and is more recent that its dependencies.
I hope your projectA and projectB are "self-contained". That means, their builds do not read any sources or build intermediate files from outside that project. They may use tools, such as gcc or, as you have it in the example above cp, but not sources outside of their directory, and not any files that are built by somebody else. In other words, if you deleted the whole rest of the tree and only build projectA and projectB by themselves with their Makefiles, they will build just fine.
In such a case, it is OK to use recursive Make.
If you use recursive Make, you have to do what you are doing,
make -C projectA
There is no better way. That is the best way to "quickly check" if the "submake" is up to date.
Related
I'm really struggling in understanding why the following makefile won't work:
all: buildFolders main.out
mv main.out build/
-echo "File compiled"
buildFolders:
mkdir -p build src
cp *.c src/
%.s: %.c
gcc -S $< -o $#
%.out: src/%.s
gcc $< -o $#
It is executed in a folder containing only the makefile and a main.c file. It should build the src and build folder, copy the main.c in the src folder and then start compiling the main.out. Unfortunately it throws the error "no rule to make target 'main.out'". Since I have the %.out that matches 'main.out' I don't see why it gives me that error. Instead it should look for the src/main.s file, create it and then use it to generate the main.out.
What am I doing wrong? Thanks
You have a number of problems.
First, listing prerequisites in order doesn't create a dependency relationship. If, for example, you ever wanted to enable parallel builds then this:
all: buildFolders main.out
doesn't force the buildFolders target to be built before main.out. These two targets both must be built before all but this doesn't tell make that there's any relationship between buildFolders and main.out. If buildFolders must be completed before main.out can be built then main.out must list buildFolders as a prerequisite.
Second, you haven't told make how to build a file src/main.c. It's built as a side-effect of the buildFolders target, but make can't know that. You need to explain to make that this file can exist. I recommend adding a rule:
src/%.c: %.c
mkdir -p src
cp $< $#
and removing the buildFolders target altogether.
However, I really question why you want to do this anyway. What's the point of copying the source files in the current directory to some sub-directory to build them? It's dangerous and confusing to have multiple copies of source files lying around because they can get out of sync with each other, then you're building older versions and you spend hours trying to understand why something doesn't work. It's a really bad idea.
I need a Makefile that allows me to enter make foo-program and, if any foo-program/**/*.hs file has changed since last build, build the target (output in foo-program/.stack-work).
Here is my directory tree:
project/
|-bar-other-program/
|-.stack-work/ # Generated output goes here
|-src/
|-BarOtherProgram.hs
|-test/
|-Tests.hs
|-foo-program/
|-.stack-work/ # Generated output goes here
|-src/
|-FooProgram.hs
|-test/
|-Tests.hs
|-notes/ # non-source, so no Make target for this
Here is what I have so far:
# evaluates to 'bar-other-program foo-program'
PROGS := $(shell find * -type f -name '*.hs' | cut -d'/' -f1 | uniq)
.SECONDEXPANSION:
$(PROGS): $$(wildcard $$#/src/*.hs) $$(wildcard $$#/test/*.hs)
# do-build $#
When I run make foo-program, whether the source has changed or not, I get:
make: Nothing to be done for 'foo-program'
UPDATE: My final (non-abstracted) Makefile can be found on GitHub. Note that my solution took a different turn than I intended when I wrote up this question. Looking at that Makefile also might also make it more clear as to my original goal.
I am not quite sure of the the purpose of cut -d'/' there.
But if you just want a list of *.hs files in the current directory (recursively found) and then build a target/executable based on whether they have changed, you can do something like this:
PROGS = $(subst ./,,$(shell find . -type f -name '*.hs'))
DEPS = $(addprefix stackwork/,$(addsuffix .dep,$(basename $(PROGS))))
DIRS = $(dir $(DEPS))
.PHONY: foo-program
foo-program: $(DEPS) $(DIRS)
stackwork/%.dep: %.hs | $(DIRS)
#echo making $#
#touch $#
$(DIRS):
#echo creating dir $#
#mkdir -p $#
clean:
#rm -rf $(DEPS) $(DIRS)
Where:
PROGS is your list of .hs files
DEPS is a list of generated dependency files (empty but date stamps will be used)
DIRS is a list of output directories that need to be created (I guess they don't exist by default since they are output folders?)
foo-program is a rule that you can call (PHONY because at the moment it does not create a real file)
%.dep: %.hs is a rule how to generate a .dep file (this could be a .o .obj or any other file type) which depends on its .hs file equivalent.
$(DIRS): is a rule to create your output directories if needed.
So if the .dep files don't exist, all of the .hs files will be "compiled". If all the .dep files exist and are up to date, then nothing will be compiled. If one or more file is out of date then just those files will be built. Here is the output of running this on my PC with a few test files:
admin#osboxes:~/sandbox$ make
creating dir stackwork/
creating dir stackwork/test/
creating dir stackwork/test/test2/
making stackwork/file.dep
making stackwork/test/file.dep
making stackwork/test/test2/file2.dep
admin#osboxes:~/sandbox$ make
make: Nothing to be done for 'foo-program'.
admin#osboxes:~/sandbox$ touch test/file.hs
admin#osboxes:~/sandbox$ make
making stackwork/test/file.dep
admin#osboxes:~/sandbox$ make
make: Nothing to be done for 'foo-program'.
Hi!
I started messing with makefiles a few days ago, so I gave myself a exercise to learn as well as making my life easier.
I basically want to read the directory the makefile is in (root) and use luamin to compress the file as much as possible before I deploy it to our server. But I would like to have it as flexible as possible, so depending on where said file is in the directory it should mirror it to the server.
So if it finds a file in a sub folder called home it should create a new folder with the same name with the compressed file within. I have gotten the compression of files in the root folder working as well as creation of the directories where the files should reside.
objs = $(wildcard *.lua)
dirs = $(wildcard */)
compress: $(objs)
mkdir -p .build
luamin -f $(objs) > .build/$(objs)
mkdir .build/$(dirs)
clean:
rm -rf ./.build
deploy: .build
cp ./.build/* ~
If you use GNU make, there are several features that really help to do what you want. Warning: this works if and only if your file names do not contain spaces:
srcfiles := $(shell find . -path .build -prune -o -type f -name '*.lua' -print)
dstfiles := $(addprefix .build/,$(srcfiles))
.PHONY: compress clean deploy
compress: $(dstfiles)
$(dstfiles): .build/%: %
mkdir -p $(dir $#)
luamin -f $< > $#
clean:
rm -rf ./.build
deploy: .build
cp ./.build/* ~
Explanation:
The shell make function is used to run the find command that searches all subdirectories, except .build, for *.lua files. The result is assigned to the srcfiles make variable.
The addprefix make function is used to add the .build/ prefix to all words of the srcfiles make variable and assign the result to the dstfiles make variable.
The compress target is the first (real) target in the Makefile. It is thus the default goal that gets run when invoking just make. It is the same as invoking make compress. The compress target is declared as phony. This tells make that it is not a real file, just like clean and deploy. The compress target depends on all destination files. If one is missing or older than its corresponding source file, it must be rebuilt.
The make static pattern rule $(dstfiles): .build/%: %... declares a generic rule where each destination file (.build/./foo/bar/baz.lua) depends on the corresponding source file (./foo/bar/baz.lua). The recipe creates the destination directory (./foo/bar/), computed thanks to the dir make function. Then, it applies the luamin command. The recipe makes use of the $# and $< automatic variables.
I was investigating on the same question here, but I was not very clear of what I was asking, even for myself. Sorry for those who spent time answering my unclear question.
So let's try again with a more realistic example. We consider this structure:
.
├── Makefile
└── src/
├── bar
├── foo
└── Makefile
Where the main Makefile is:
all: src/foobar
src/foobar:
make -C $(dir $#)
And the sub-makefile is:
foobar: foo bar
join $^ > $#
If I run make for the first time (from ./) everything works as expected, foobar is produced.
$ make
make -C src/
make[1]: Entering directory '/project/src'
join foo bar > foobar
make[1]: Leaving directory '/project/src'
$ make
make: Nothing to be done for 'all'.
However if I touch any of the foobar dependencies. The parent Makefile will not regenerate the target. Here, I perfectly understand the behavior of Make, but I want to tell it to be aware of foobar' dependencies.
$ touch src/foo
$ make
make: Nothing to be done for 'all'.
My current solution which is not very neat is to ask for the dependencies. So the src/Makefile become:
src=foo bar
foobar: $(src)
#echo "Joining"
join $^ > $#
files: $(src)
#echo $^
And the ./Makefile:
all: src/foobar
src=$(addprefix src/,$(shell make --no-print-directory -C src files | tr '\n' ' '))
src/foobar: $(src)
make -C $(dir $#)
I must also say that this particular example could be simplified using a single Makefile only. My real example is quite more complex. The src/Makefile generate an executable while the parent Makefile do lots of other things (packing in a specific format, generate the documentation, build other sub-makefiles and so on). Thus, I want to keep these tasks well separated and I need to different Makefiles.
In the main Makefile create a dependency for the child target or directory that is always in need of building, and let the child Make then do the real work.
There is a good example here: http://owen.sj.ca.us/~rk/howto/slides/make/slides/makerecurs.html.
To translate for your case, change your main Makefile to be:
all: src/foobar
src/foobar: force
$(MAKE) $(MFLAGS) -C src
force:
true
I also added $(MFLAGS) which will pass same flags from parent to child make.
I would like to change the working directory of a makefile.
(Extraneous info: I have a legacy makefile that I mostly want to reuse, though many targets and generated deps files make assume that the working directory will not be different. My idea is to create a makefile for my newer project, which is in a different directory, and include the old one, and set the working directory to the old directory.)
I easily can do this from the command line with
make -f /path/to/new/makefile -C /path/to/old/makefile
The users of this makefile would like not to type that out every time.
Attempt 1
Use MAKEFLAGS in the makefile itself. But neither of these seem to have any effect. (I understand why -f couldn't have an effect; I'm really wondering about -C.)
I've looked at http://www.gnu.org/software/make/manual/html_node/Options-Summary.html, but I can't find anything about what is allowed in MAKEFLAGS and what isn't.
Attempt 2
Create a makefile2 with the new targets
include path/to/old/makefile
foo: bar
and then makefile passes everything through
%:
$(MAKE) -f $(abspath makefile2) -C path/to/old/makfele /$*
I don't get nice autocompletion, parallel jobs don't work, and debug options (dry run) doesn't work.
So
(1) Why doesn't -C work MAKEFLAGS (it does work, but I made a mistake; it doesn't work, and it is documented; it doesn't work, and it is not documented but it is intentional; it doesn't work, and it is a bug)?
(2) Is there a better way of change a makefile's working directory?
Some things are wrong here :
make -f /path/to/new/makefile -C /path/to/old/makefile
The -f options specifies the name of the Makefile to be found when searched in the directory specified with -C (or the current directory if not provided). So it is more :
make -C /path/to/old/Makefile -f name_of_old_makefile
If the name is simply Makefile or makefile, there is no need to provide the -foption.
The MAKEFLAGS variable does not contains -f or -C in the called sub-Makefile.
To be able to pass multiple targets to another makefile, you need the MAKECMDGOALS variable.
Ultimately, all you have to do in your new Makefile is to have someting like this :
all:
$(MAKE) $(MAKEFLAGS) -C /path/to/old/Makefile -f old_Makefile_name $#
%:
$(MAKE) $(MAKEFLAGS) -C /path/to/old/Makefile -f old_Makefile_name $(MAKECMDGOALS)