Just simple Makefile:
a/% b/%:
#echo $#
When I do
make a/a b/b
It's OK as expected that:
a/a
b/b
But when I do
make a/a b/a
It's appears that:
a/a
make: Nothing to be done for `b/a'.
How can I get the expect return
a/a
b/a
Tested with make version both v3.81 and v3.82 on Linux and macOS
Given your makefile...
a/% b/%:
#echo $#
Consider what happens when you invoke make a/a b/b. make notices that the rule a/% b/%: matches with the stem a (i.e. the built in variable $* will be a) and runs the command. Because your rule has multiple targets make now considers both a/a and b/a to have been updated.
Make then considers the next target specified on the command line b/b. That hasn't yet been updated and so make runs the same rule again but with the stem b. So the rule is run twice -- once for each pattern stem a and b.
Now consider what happens when you invoke make a/a b/a. This time both targets will match the same rule but with the same stem a. Hence make, having run the rule with the stem a considers both a/a and b/a to have been updated and sees no need to rerun the rule for second command line target b/a.
It's not entirely clear what behaviour you require but if you want the same rule to be invoked multiple times for different targets even though the pattern stem is the same then you might want something like...
# Possible targets (for illustration purposes).
#
TARGETS := a/a a/b b/a b/b
$(TARGETS): %:
#echo $#
The above gives...
G.M.> make -f multi-wildcard-target-in-makefile.mk a/a b/b
a/a
b/b
G.M.> make -f multi-wildcard-target-in-makefile.mk a/a b/a
a/a
b/a
If you do not want to hardcode possible targets as G.M. proposed, you may make some magic:
$ cat Makefile
define recipe
$(1):
#echo $$#
endef
PATTERNS=a/% b/%
$(foreach pattern,$(PATTERNS),$(eval $(call recipe,$(pattern))))
Testing:
$ make a/a b/a
a/a
b/a
$ make a/a b/b
a/a
b/b
The behavior you observe is described in GNU make docs:
Pattern rules may have more than one target. Unlike normal rules, this does not act as many different rules with the same prerequisites and recipe. If a pattern rule has multiple targets, make knows that the rule’s recipe is responsible for making all of the targets. The recipe is executed only once to make all the targets.
Related
I have a chain of pattern dependencies in a makefile, and in the end they should come together in one file, e.g.: *.x -> *.y -> onefile.z
So I made the files like this:
$ touch a.x b.x
and the rules:
%.y: %.x some-other-script
touch $#
onefile.z: %.y second-other-script
touch $#
This rule does not work:
$ make onefile.z
make: *** No rule to make target '%.y', needed by 'onefile.z'. Stop.
Using a wildcard:
%.y: %.x some-other-script
touch $#
z: $(wildcard *.y) second-other-script
touch $#
This does not work either: it sees there are no *.y files and proceeds making onefile.z skipping the first rule.
$ make onefile.z
touch onefile.z
$ ls
a.x b.x onefile.z Makefile
I probably could merge two rules into one, but in the real application, there are more steps, and some are making requests over HTTP and take much time, and in fact should not be repeated without a reason.
Is there a way to make such a dependency?
onefile.z: %.y second-other-script is a regular rule, not a pattern rule or a static pattern rule, so the % is interpreted literally. Even if it were a pattern rule, how is make supposed to infer what the stem is supposed to match?
$(wildcard *.y) tells make to find all the files that match *.y, but of course there are none yet so it returns an empty string.
The following should work, if I've understood your question correctly:
xfiles := $(wildcard *.x)
yfiles := $(xfiles:.x=.y)
%.y: %.x some-other-script
touch $#
onefile.z: $(yfiles) second-other-script
touch $#
See the Gnu Make documentation on
Wildcard functions $(wildcard ...)
Substitution functions $(foo:from=to)
I have a directory structure that looks like this:
$ tree
.
|-- dir
| `-- subdir
| `-- data
`-- makefile
where data is a file. My makefile looks like this:
all: dir/analysis
.SECONDEXPANSION:
%/analysis: %/subdir
%/analysis: $(addsuffix /data, $$^)
#echo TARGET: $# DEPS: $^
touch $#
When I run make, I would expect the result to look like this:
TARGET: dir/analysis DEPS: dir/subdir/data dir/subdir
touch dir/analysis
Instead, it just reports
make: *** No rule to make target `dir/analysis', needed by `all'. Stop.
If I change the first rule to dir/analysis: dir/subdir then it works as I expected. So I suspect that make ignores the first rule and skips straight to the second when the first rule is %/analysis: %/subdir. It also works as expected when both rules have dir/analysis as their target instead of just the first rule. MadScientists's answer to a different question here seemed to apply to my problem. I tried adding rules like
dummy_target: dir/subdir
mkdir -p dir/subdir
and
dir/subdir:
mkdir -p dir/subdir
to the end of makefile to try to make the dependency on the first rule an explicit target but this didn't change anything. I'm pretty new to make, so I'm probably missing something pretty stupid, but I can't for the life of me figure it out. How do I get the first and second rules to execute in the order they're written? I'm using Make version 3.81 in case that matters.
--EDIT--
If I actually add a command after the first rule, like #echo RULE 1 then that command executes and not the second one.
I think that you understand the makefile:
# Original
all: dir/analysis
.SECONDEXPANSION:
%/analysis: %/subdir
%/analysis: $(addsuffix /data, $$^)
#echo TARGET: $# DEPS: $^
touch $#
like this:
By default we make dir/analysis
We request secondary expansion
We say that whatever/analysis depends on whatever/subdir. So
that makes dir/subdir a prerequisite of dir/analysis
We say also that whatever/analysis depends on the thing we get by
suffixing /data to the prior prerequisites of whatever/analysis. (Secondary
expansion of $$^ gives us the prior prerequisites of the target). And
since the prior prerequisites of dir/analysis are dir/subdir, that now
makes dir/subdir dir/subdir/data the new prerequisites of dir/analysis.
Hence the output of the recipe ought to be:
TARGET: dir/analysis DEPS: dir/subdir/data dir/subdir
touch dir/analysis
This understanding is badly wrong. You're confusing and conflating the operation
of pattern rules with the operation or ordinary rules.
If a makefile says, e.g:
# A
xx: xa
xx: xb
xx: xc
touch $#
or even:
# B
xx: xa
xx: xb
%x: %c
touch $#
then the prerequisites of all the empty rules for the target xx are combined
with those of the (one) non-empty rule when xx is considered as a target. So
# A is equivalent to:
xx: xa xb xc
touch $#
and # B is equivalent to:
xx: xa xb
%x: %c
touch $#
and in both cases the prerequisites of xx are xa xb xc.
However:
%x: %a
%x: %b
touch $#
is not equivalent to:
%x: %a %b
touch $#
If you ever write an empty pattern rule, its effect is simply to delete
any prior pattern rule with the same target and prerequisite patterns. And if you
ever write a non-empty pattern rule, you simply replace
any prior pattern rule with the same target and prerequisite patterns. See
10.5.6 Canceling Implicit Rules
So:
.SECONDEXPANSION:
%/analysis: %/subdir
%/analysis: $(addsuffix /data, $$^)
#echo TARGET: $# DEPS: $^
touch $#
is equivalent to:
.SECONDEXPANSION:
%/analysis: $(addsuffix /data, $$^)
#echo TARGET: $# DEPS: $^
touch $#
Then when this pattern rule is considered with respect to dir/analysis,
there are no prior prerequisites: $^ will expand to the empty string, and
in secondary expansion, so will $$^. So finally the recipe is equivalent to:
# Residual
%/analysis: /data
#echo TARGET: $# DEPS: $^
touch $#
You can satisfy yourself of this by running both of the # Original and
# Residual makefiles in debug mode (-d) and comparing the outputs.
This explains why the outputs in both cases conclude:
make: *** No rule to make target 'dir/analysis', needed by 'all'. Stop.
A pattern rule will only be instantiated to make a target if doing so offers a way for the target to be made. Why else select it? Since the prerequisite /data does not exist, the pattern rule
is not viable and is discarded. Just as if you tried to make foo.o with the makefile:
%.o: %c
touch $#
when there is no foo.c in the directory.
If you really want to see the output you were expecting, then you can get it from:
.PHONY: all clean
all: dir/analysis
%/analysis: %/subdir %/subdir/data
#echo TARGET: $# DEPS: $^
touch $#
clean:
rm -f dir/analysis
But it is hard to believe that is what you really want to see. This makefile
makes the analysis dependent on the data and also on the directory where
the data resides. What can be the point of that?
%/analysis: %/subdir/data
presumably expresses the desired relationship between the data and the analysis:-
If the data doesn't exist then the analysis is out of date and cannot be made (till you get some data).
If the data exists and is older than the analysis then the analysis does not
need to be made.
If the data exists and is newer than the analysis then the analysis can and will be
made.
By making dir/subdir an independent prerequisite all that you achieve is to introduce
a requirement to remake the analysis if it becomes older than the directory in
which the data resides - regardless of the data. So if, e.g. I run touch dir/subdir,
that will require make to re-run the analysis, even though the data hasn't changed.
I can make sense of your motivation only by supposing that in
reality you also want make to make the data, and the directory where it resides, if
they happen not exist when an analysis is required. If that is the situation then
you want a makefile on the lines of:
.PHONY: all clean
all: dir/analysis
.SECONDARY:
%/subdir:
mkdir -p $#
%/subdir/data: | %/subdir
touch $#
%/analysis: %/subdir/data
#echo TARGET: $# DEPS: $^
touch $#
clean:
rm -f dir/analysis dir/subdir/data
Here, the pattern rule:
%/subdir/data: | %/subdir
makes %/subdir an order-only prerequisite
of %/subdir/data. It means that /dir/subdir is not considered when determining whether /dir/subdir/data needs
to be made, but if it is determined that /dir/subdir/data is to be made, then /dir/subdir will be made first. This
way, /dir/subdir will be created, if it does not exist, when you need it to put the data there, but will have no influence
on whether you need to make the data or the analysis.
The special target .SECONDARY is a technicality. It directs make not to automatically delete any subsequent targets
that it deduces to be intermediate artefacts that emerge from chained pattern rules. Without it, in this example make
would deduce that dir/subdir/data and dir/subdir/ are just waste-products of making dir/analysis and auto-delete them
at the end.
If you run this makefile initially with no dir/subdir/data and no dir/subdir/ you get:
$ make
mkdir -p dir/subdir
touch dir/subdir/data
TARGET: dir/analysis DEPS: dir/subdir/data
touch dir/analysis
And subsequently:
$ make clean
rm -f dir/analysis dir/subdir/data
$ make
touch dir/subdir/data
TARGET: dir/analysis DEPS: dir/subdir/data
touch dir/analysis
And then:
$ make
make: Nothing to be done for 'all'.
$ touch dir/subdir
$ make
make: Nothing to be done for 'all'.
Consider this makefile:
%: %.c
#echo making $#
#touch $#
.SECONDEXPANSION:
%.pid: $$(basename $$#)
$(<D)/$(<F) --pidfile=$<.pid
Here, the first rule builds a program and second rule starts it, producing a pid-file. Note: I know that secondary expansion is unnecessary in this example; the real makefile is more complex and I really need secondary expansion there.
So, typing make foo.pid, I expect Make to build foo from foo.c by the first rule and then run ./foo --pidfile=foo.pid by the second one.
However, it does not seem to work:
$ make -f Makefile.test foo.pid
make: *** No rule to make target 'foo.pid'. Stop.
This somehow relates to secondary-expanded dependencies which are provided by pattern rules. If I write either
%.pid: % in the second rule (i. e. get rid of secondary-expansion), or
foo: %: %.c in the first rule (i. e. write an explicit static pattern rule),
it all suddenly works. Why? Is this a limitation of GNU Make? In my case, I'd like to avoid pre-listing all possible programs in the first rule.
I think your situation is described in section 10.5.5 Match-Anything Pattern Rules. Whay you have here is a non-terminal match-anything rule, which is not allowed to match a file name that indicates a specific type of data.
If you had let's say
%:: %.c
#echo making $#
#touch $#
it would work.
File Name: Makefile.mk
%: foo
#echo %: $# with foo
foo:
#echo foo
Run
$ make -f Makefile.mk test
Output:
foo
%: Makefile.mk with foo
%: test with foo
I am running this in GNU Make 3.81 version.
I Don't understand, why file name also printed(%: Makefile.mk with foo).
Can some one please explain me?
This is because of how makefiles are remade. That is to say that
Sometimes makefiles can be remade from other files
and
If a makefile can be remade from other files, you probably want make to get an up-to-date version of the makefile to read in
so
after reading in all makefiles, make will consider each as a goal target and attempt to update it.
Which then matches against your match-anything rule and triggers the way you see.
If you add an explicit Makefile.mk: ; target to your makefile it will override the match-anything target and prevent this.
I want to make a language depend target. In Particular: I have one source-file and I want to create different Objects which where add to the corresponding language folder. That single source file will differ in the C-Flags, the compiler will get. As long as I used it in a static way, it works quite fine.
de/info.o en/info.o es/info.o : info.c
$(ECHO) (DEP) $< for $#
Now I thought, it would be great if it is a bit more dynamic, in case i'll add a new language depending file. So I used a wildcard as followed:
de/%.o en/%.o es/%.o : %.c
$(ECHO) (DEP) $< for $#
But now it just make the first target and ignores the rest. The Make-Debug prints the following thing:
Successfully remade target file `de/info.o'.
Considering target file `en/info.o'.
File `en/info.o' was considered already.
Just in case: No, the objects do not exist. So there is no target, but an existing dependencie, so make should execute the rules.
EDIT: Found a solution for that Problem.
define FOO
$(1)/%.o : %.c
$(ECHO) $$< for $(1)
endef
$(foreach lang,$(LANGUAGE_LIST), $(eval $(call FOO,$(lang))))
Inspired by: http://www.gnu.org/software/make/manual/make.html#Eval-Function
Pattern rules work differently than implicit rules. While an implicit rule such as
a b c: d
command
is equivalent to the longer notation
a: d
command
b: d
command
c: d
command
this does NOT hold for pattern rules. Pattern rules with multiple targets are explicitly required to build all of their targets in a single invocation of command. Thus you would have to write
$ cat GNUmakefile
all: de/x.o en/x.o es/x.o
de/%.o: %.c
#echo $# from $<
en/%.o: %.c
#echo $# from $<
es/%.o: %.c
#echo $# from $<
$ gmake
de/x.o from x.c
en/x.o from x.c
es/x.o from x.c
The relevant documentation is found in 10.5.1 Introduction to Pattern Rules of the GNU make manual:
Pattern rules may have more than one target. Unlike normal rules, this does not act as many different rules with the same prerequisites and recipe. If a pattern rule has multiple targets, make knows that the rule’s recipe is responsible for making all of the targets. The recipe is executed only once to make all the targets. When searching for a pattern rule to match a target, the target patterns of a rule other than the one that matches the target in need of a rule are incidental: make worries only about giving a recipe and prerequisites to the file presently in question. However, when this file’s recipe is run, the other targets are marked as having been updated themselves.