I need to look at which commands are being used by make, but running command make --dry-run does not show the commands used by an internal make -C /foo.
Is there any way to make this work recursively?
To allow -n to work recursively, invoke make recursively with $(MAKE) instead of just make.
foo:
$(MAKE) -C /foo
Related
I have
$(foreach ___project___, $(UNIT_TEST_STUBS),$(MAKE) -C ../../$(___project___) $(UT_CMD) || exit 1;)
I want make to be parallel INSIDE each submake but I don't want the submakes to be executed in parallel.
How do I do this?
As #Michael Livshin points out, you already seem to have answered your own question.
Might be neater to rely on make rather than shell syntax to tie a load of commands together though.
Basically you want make to see something like this:
.PHONY: all
all:
${MAKE} -C ../../foo/ -j9 ut-cmd
${MAKE} -C ../../bar/ -j9 ut-cmd
${MAKE} -C ../../bum/ -j9 ut-cmd
Auto generation from a list is fairly straight-forward.
submakes := foo bar bum
define generate-submake
${MAKE} -C ../../$1/ ut-cmd
endef
.PHONY: all
all: ; $(foreach _,${submakes},$(call generate-submake,$1))
Note the blank line in the definition of generate-submake. It's important.
Run this with make -j9.
If you really want everything in this makefile to run serially (but the sub-makes to be parallel), then just introduce a .NOTPARALLEL target.
.NOTPARALLEL:
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)
In this project, a top level rule looks like this:
all:
for l in $(LIBDIRS); do $(MAKE) -C $$l all; done
If I run make -jx, the files in each directory are compiled in parallel, but because of this bash loop, make doesn't move onto files in the next library until everything is done in the current one. What's the best way to change the loop so that it call truly be done in parallel? I only use gnumake, so gnu extensions are fine.
* Edit * as an aside, I was trying something like this
ALL_DEPENDENCY = $(foreach l, $(LIBDIRS), $(l).PHONY_LIB_RULE)
.PHONY: $(ALL_DEPENDENCY)
%.PHONY_LIB_RULE:
$(MAKE) --no-print-directory -C $(patsubst %.PHONY_LIB_RULE,%,$#) all
all: $(ALL_DEPENDENCY)
but these rules aren't tripped.
You can check this answer for an example of how to do this more correctly: makefile: foreach "make -C" call
I wonder why this won't delete/clean *.o files generated when running make?
# UNIX Makefile
CXX = g++
LD = g++
CXXFLAGS = -g
testlfunction: lfunction.o lfunctionlist.o lprocessor.o testlfunction.o
$(LD) -o $# $^
clean:
rm *.o testlfunction
before it use to be
$(RM) *.o testlfunction
but it didn't work also ;(
Why is this?
To check what really happens, run "make clean" and examine the output of that command.
Is it nothing? Then there might be a file called "clean" in the current directory. Remove it and try again.
Does it start with "rm ..."? Then it seems to be normal.
In all other cases, tell us the exact output you get.
To check whether the commands are really run, insert some "echo" commands before and after the "rm" command. Are they executed?
And finally, did you distinguish between tab characters and spaces? In Makefiles the difference is important. Commands must be indented using tabs.
One way that make clean can 'fail' to execute anything is if there is a file called clean in your directory, possibly the result of running make -t clean. This would create a file, so when you next ran make clean, it would appear up to date - it has no dependencies, so there is no reason to run the action.
If you use GNU Make, ensure that you have the line:
.PHONY: clean
That will stop make -t from creating clean and will ensure that the actions are run.
I need to work on a system that uses automake tools and makes recursively.
'make -n' only traces the top level of make.
Is there a way to cause make to execute a make -n whenever he encounters a make command?
Use $(MAKE) to call your submakefiles, instead of using make. That should work. Check out How the MAKE variable works in the manual. Here's a quick example:
Makefile:
all:
#$(MAKE) -f Makefile2
Makefile2:
all:
#echo Makefile2
Command line:
$ make
Makefile2
$ make -n
make -f Makefile2
echo Makefile2
$
Does your recursive makefile look like this:
foo:
make -C src1
make -C src2
Or like this:
foo:
${MAKE} -C src1
${MAKE} -C src2
I think you need to use the second style if you want flags passed to child make processes. Could be your problem.
Setting the environment variable "MAKEFLAGS" to "n" may do what you need.
There are some more advanced tricks for tracing make commands here:
http://www.cmcrossroads.com/ask-mr-make/6535-tracing-rule-execution-in-gnu-make
The simplest of these tricks comes down to adding SHELL="sh -x" to your make command (running without "-n" in that case).