I have the following make file:
$ cat foo.mk
.INCLUDE_DIRS += ..
$(info include_dirs is [${.INCLUDE_DIRS}])
include upper.mk
In the directory one level above, I have
$ cat ../upper.mk
$(info HERE!!)
When I run the makefile, I get:
$ make -f foo.mk
include_dirs is [/usr/include /usr/local/include /usr/include ..]
foo.mk:3: upper.mk: No such file or directory
make: *** No rule to make target 'upper.mk'. Stop.
Nor does this work even if I specify an absolute path:
.INCLUDE_DIRS += /absolute/path/to/include/file
Why is make not finding upper.mk, even though I have added the directory where it can be found (..) to the .INCLUDE_DIRS variable?
Note that this does work:
$ make --include-dir=.. -f foo.mk
include_dirs is [.. /usr/include /usr/local/include /usr/include]
HERE!!
Version info:
$ make --version
GNU Make 4.0
Unfortunately .INCLUDE_DIRS is effectively read-only: GNU make constructs a value for it based on a default list of search directories and whatever additions you specify via the -I or --include-dir command-line option, but thereafter GNU make does nothing with the variable.
If you want to add .. to the list of search directories for included makefiles, the correct way to do it is to invoke make as make -I ..
Related
I have a directory with test inputs and outputs. I wanted make to automatically test my program against this directory after build, for convenience. Thus I needed to somehow force the test target of Makefile to depend on the entire testing directory (it's called good, because it contains valid inputs and outputs for the program)
I read this question and the accepted answer and the comments about deleted files under this answer: Makefile rule that depends on all files under a directory (including within subdirectories) And, incorporating advice from this answer & comments, I came out with this:
my#comp:~/wtfdir$ cat Makefile
test : test.sh $(shell find good)
./test.sh
my#comp:~/wtfdir$
For the sake of MCVE, test.sh is very rudimentary:
my#comp:~/wtfdir$ cat test.sh
echo "blah"
my#comp:~/wtfdir$
However, I noticed, this behaves in a rather unexpected way:
my#comp:~/wtfdir$ ls good
test1 test1.out
my#comp:~/wtfdir$ make
./test.sh
blah
my#comp:~/wtfdir$ touch good/test1
my#comp:~/wtfdir$ make
cp good/test1 good/test1.out
./test.sh
blah
my#comp:~/wtfdir$
Why (expletive redacted) does modifying test1 cause make to overwrite test1.out with test1??? I'm not a big fan of data losses, you know.
What's going on here?
Your Make appears to be GNU Make. Here's why this happens. Your recipe:
test : test.sh $(shell find good)
./test.sh
adds to the prerequisites of test every file and directory that is listed
by find good in the current directory, which happen to be:
good
good/test1
good/test1.out
So to make target test, Make begins by determining if any of the specified
or built-in recipes require it to rebuild any of the prerequsities:
test.sh good good/test1 good/test1.out
Among its built-in recipes it finds:
%.out: %
# recipe to execute (built-in):
#rm -f $#
cp $< $#
as you can verify by running:
$ make --print-data-base | grep -A4 '%.out'
The rule for this recipe is matched by:
good/test1.out: good/test1
and by doing:
$ touch good/test1
you have made good/test1.out out of date with respect to good/test1.
So make executes the recipe:
#rm -f good/test1.out
cp good/test1 good/test1.out
the visible output of which is what you observed:
cp good/test1 good/test1.out
Then it proceeds with the recipe for test:
./test.sh
blah
There is always a risk of such booby-traps if you write a makefile that blindly
generates at runtime some set of preqrequisites or targets you don't know beforehand.
You could avoid this one in particular by explicitly deleting the offending
implicit pattern rule in your makefile by writing:
%.out: %
with no recipe. And you can avoid all possible booby-traps of this sort by disabling all
built-in recipes, with:
$ make --no-builtin-rules ...
but that will require you to write for yourself any builtin-recipes that your
makefile relies on.
The best solution for you is probably to amend your makefile as follows:
PREREQS := $(shell find good)
test : test.sh $(PREREQS)
./test.sh
$(PREREQS): ;
Then the last line explicitly specifies an empty recipe
for each of the $(PREREQS), and Make will not consult any pattern rules for targets
that have explicit recipes.
You should additionally make test a phony target:
.PHONY: test
for the avoidance of the booby-trap where something creates a file called test in the build directory.
When I run make --dry-run on
all:
false # $(MAKE)
using GNU Make 4.2.1, I get back the following error. Why?
false # make all
make: *** [Makefile:2: all] Error 1
https://www.gnu.org/software/make/manual/make.html#Instead-of-Execution:
The -n, -t, and -q options do not affect recipe lines that begin with + characters or contain the strings $(MAKE) or ${MAKE}.
(--dry-run is an alias for -n.)
https://www.gnu.org/software/make/manual/make.html#MAKE-Variable:
subsystem:
cd subdir && $(MAKE)
[...]
As a special feature, using the variable MAKE in the recipe of a rule alters the effects of the -t (--touch), -n (--just-print), or -q (--question) option. Using the MAKE variable has the same effect as using a + character at the beginning of the recipe line.
[...]
Consider the command make -t in the above example. (The -t option marks targets as up to date without actually running any recipes; see Instead of Execution.) Following the usual definition of -t, a make -t command in the example would create a file named subsystem and do nothing else. What you really want it to do is run cd subdir && make -t; but that would require executing the recipe, and -t says not to execute recipes.
The special feature makes this do what you want: whenever a recipe line of a rule contains the variable MAKE, the flags -t, -n and -q do not apply to that line. Recipe lines containing MAKE are executed normally despite the presence of a flag that causes most recipes not to be run.
Your recipe contains $(MAKE), so it gets executed despite --dry-run. false returns an exit status of 1, which is considered an error by make.
I want make to remove all files except the source files and the make rule file (i.e. the file named makefile), so I added a phony rule at the end of my makefile:
.PHONY:clean
clean:
$(shell ls | grep -v "[.][ch]" | grep -v makefile | xargs rm)
This does what I intend. But make always complains
make: Nothing to be done for 'clean'.
After I run make clean. Why does this message appear? And how can I make it disappear?
The use of $(shell ...) is unnecessary. It runs the command, then the output is used as if it was part of the Makefile. There is no output, so the resulting rule is:
clean:
i.e. the actual list of commands to update the clean target is empty.
So here's a Makefile to install foo.conf, based on a master copy called foo.conf.master. It installs it to the current directory rather than /etc, just for testing purposes:
all: foo.conf.copied
foo.conf.copied: foo.conf.master foo.conf
cp foo.conf.master foo.conf
touch $#
# Recipe to tell make that it is okay for foo.conf not to exist beforehand.
foo.conf:
So then create foo.conf.master:
$ touch foo.conf.master
$
and you're ready to test:
$ make
cp foo.conf.master foo.conf
touch foo.conf.copied
$
The point is that if I (with my "trusted" sysadmin hat on) modify foo.conf.master then make (possibly called by cron) will roll out the update:
$ touch foo.conf.master
$ make
cp foo.conf.master foo.conf
touch foo.conf.copied
$
But equally important: if I (with my "rogue" sysadmin hat on) modify the installed version then make will back out the update:
$ touch foo.conf
$ make
cp foo.conf.master foo.conf
touch foo.conf.copied
$
Woohoo.
Okay, so now the problem: obviously foo.conf isn't the only file I want do this for, so I need to change my static rules to pattern rules. Okay, that's easy: substitute foo.conf for % in targets and dependencies, substitute foo.conf for $* in the commands, and make a minor modification to the last recipe (which would otherwise become only '%:') so that it doesn't look like I'm trying to cancel a builtin pattern rule.
So clean up and create this Makefile:
all: foo.conf.copied
%.copied: %.master %
cp $*.master $*
touch $#
# Recipe to tell make that it is okay for foo.conf not to exist beforehand.
# Nop tells make that I'm not *cancelling* a pattern rule here
# (see http://stackoverflow.com/questions/34315150/make-implicit-rules-dont-work-without-command).
%: ;
But this doesn't work:
$ make
make: *** No rule to make target `foo.conf.copied', needed by `all'. Stop.
$
The error message is misleading; it is really foo.conf that it doesn't know how to make, which can be demonstrated by adding the following at the bottom of the Makefile:
foo.conf:
touch $#
But then that's a static rule again, which I don't want.
There are a couple more requirements I would also like to satisfy, which the above example doesn't demonstrate. These are:
foo.conf should be installable anywhere in the filesystem (e.g. /etc/foo/server/foo.conf)
foo.conf.master should be in a central directory, or subdirectly thereof, for all master versions, preferably without the '.master' extension (e.g. ~/poor-mans-puppet/master-files/etc/foo/foo.conf)
foo.conf.copied should be in a central directory, not in the same directory as foo.conf (e.g. ~/poor-mans-puppet/timestamp-files/etc/foo/foo.conf)
After much googling, hair pulling, I'm asking here! Any ideas please? (PS: if copying Makefiles from here, remember to change indentation back to tabs.)
Mad Scientist below suggested an elegant static rule, but I really need it to be a pattern rule. The reason is that I need to hook extra dependencies in using rules:
all: <new-dependency>
rather than hooking them in using variables:
STUFF_ALL_SHOULD_DEPEND_ON += <new-dependency>
The reason for this requirement is for consistency with how other (non-%.copied) targets are handled in my very large Makefile.
However, based on Mad Scientist's idea, I tried the following, which didn't work, but perhaps helps somebody to help me:
all: foo.conf.copied
%.copied: %.master %
$(eval FILES_FOR_WHICH_AN_EMPTY_RECIPE_ARE_NEEDED += $$*)
cp $*.master $*
touch $#
define GENERATE_STATIC_EMPTY_RULE
$(1):
endef
$(foreach X,$(FILES_FOR_WHICH_AN_EMPTY_RECIPE_ARE_NEEDED),$(eval $(call GENERATE_STATIC_EMPTY_RULE,$(X))))
Can you explain why you're using this extra ".copied" file? Why don't you just use:
%: %.master ; cp $< $#
?
Anyway, you're running afoul of make's special rules related to match-anything rules (pattern rules like % that can build everything). If you change your pattern so it's not match-anything, like %.conf: ; then it will work. However you probably don't want to assume that all files end in .conf.
Alternatively you can use static pattern rules, like this:
FILES_TO_COPY = foo.conf bar.conf biz.baz
all: $(FILES_TO_COPY:%=%.copied)
$(FILES_TO_COPY:%=%.copied): %.copied : %.master %
cp $*.master $*
touch $#
and you don't need the extra pattern rule.
In the end, I dynamically generated static rules. The following pseudo-code hopefully makes the actual Makefile easier to understand:
if flag not set # flag won't be set on first call
prepare static rules
set flag # prevent running this clause again
recurse! # make invokes make
else
include static rules
do the normal thing
endif
Here's the real Makefile:
ifeq ($(MAKELEVEL),0)
all:
for X in $(patsubst %.copied,%,$^); do \
echo "$$X.copied: $$X.master $$X"; \
echo " cp $$X.master $$X"; \
echo " touch \$$#"; \
echo "$$X: ;"; \
done > Makefile.include
$(MAKE)
# The real dependencies on all are defined below, but while creating
# Makefile.include, we don't want make to digress and start making
# the dependencies; this pattern rule will stop it from doing that.
%.copied: ;
else
include Makefile.include
endif
all: foo.conf.copied
The outer make can be silenced by use of .SILENT and the --no-print-directory option (not shown above for clarity).
Here's the output:
$ touch foo.conf.master
$ make
cp foo.conf.master foo.conf
touch foo.conf.copied
$ touch foo.conf
$ make
cp foo.conf.master foo.conf
touch foo.conf.copied
$
I'm trying to modify a makefile to cross-compile binaries. The command in question is below:
# GNU Make solution makefile autogenerated by Premake
# Type "make help" for usage help
ifndef config
config=debug
endif
export config
PROJECTS := json openjaus openjaus-core openjaus-environment openjaus-mobility openjaus-manipulator openjaus-ugv Base Managed PingTest LargeMessageTest PdDemo GposDemo GposClientDemo StillImageSensorDemo StillImageClientDemo
.PHONY: all clean help $(PROJECTS)
all: $(PROJECTS)
json:
#echo "==== Building json ($(config)) ===="
#${MAKE} --no-print-directory -C .build -f json.make
As can be seen the makefile has several targets. They all have the same structure as the 'json' target. The command in question in question is
#${MAKE} --no-print-directory -C .build -f json.make
The '${MAKE}' variable = make (I have verified this with echo)
What does the -C do?
What does the .build do?
I'm good with -f json.make
Also, when I run make the json.make file gets created compiles file and deletes it self, so I do not have access to that file.
The error I receive when I modify the command in question is
==== Building json (debug) ====
make[1]: Nothing to be done for `/home/botbear/openwrt/trunk/staging_dir/toolchain- arm_v6k_gcc-linaro_uClibc-0.9.32_eabi/bin/arm-openwrt-linux-c++'.
The command after modifications looks like:
#${MAKE} /home/botbear/openwrt/trunk/staging_dir/toolchain-arm_v6k_gcc-linaro_uClibc-0.9.32_eabi/bin/arm-openwrt-linux-c++ --no-print-directory -C .build -f json.make
Any help is appreciated!
you can use man make to understand the parameters for make:
-C dir, --directory=dir
Change to directory dir before reading the makefiles or doing any-
thing else. If multiple -C options are specified, each is inter-
preted relative to the previous one: -C / -C etc is equivalent to
-C /etc. This is typically used with recursive invocations of
make.
-f file, --file=file, --makefile=FILE
Use file as a makefile.
so -C .build changes to the directory .build.
and i don't understand the part of your question about modifying the command.
Try to find where json.make lives. It seems that it's that makefile which creates & deletes the directory you were talking about.
From the command line it seems that make changes directory to .build and executes the json.make. Not sure how json.make ends up there. Is .build the directory which is created and then deleted?