I'm getting some unexpected results calling one makefile from another. I have two makefiles, one called /path/to/project/makefile
and one called /path/to/project/gtest-1.4.0/make/Makefile
. I'm attempting to have the former call the latter. In /path/to/project/makefile, I have
dev: $(OBJ_FILES)
$(CPPC) $(LIBS) $(FLAGS_DEV) $(OBJ_FILES) -o $(BIN_DIR)/$(PROJECT)
$(MAKE) -f ./gtest-1.4.0/make/Makefile
clean:
rm -f ./*~ ./gmon.out ./core $(SRC_DIR)/*~ $(OBJ_DIR)/*.o
rm -f ../svn-commit.tmp~
rm -f $(BIN_DIR)/$(PROJECT)
make -f gtest-1.4.0/make/Makefile clean
And in /path/to/project/gtest-1.4.0/make/Makefile
I have
all: $(TESTS)
clean:
rm -f $(TESTS) gtest.a gtest_main.a *.o
Issuing the following:
cd /path/to/project
make
Outputs:
make -f ./gtest-1.4.0/make/Makefile
make[1]: Entering directory `/path/to/project'
make[1]: Nothing to be done for `all'.
make[1]: Leaving directory `/path/to/project'
However, when I issue these commands:
cd /path/to/project
make clean
I see:
make -f gtest-1.4.0/make/Makefile clean
make[1]: Entering directory `/path/to/project'
rm -f gtest.a gtest_main.a *.o
make[1]: Leaving directory `/path/to/project'
I don't understand: In both cases, /path/to/project/makefile
is telling me it's entering the current working directory. In the first case, it doesn't think it has work to do (when it does) and in the second case, it's able to find the appropriate directive (when the output is telling me it's looking in the wrong directory) yet it tries to run the rm
command in /path/to/project
, instead of /path/to/makefile/gtest-1.4.0/make/
.
Am I missing something fundamental to calling makefiles from one another? Have I made an egregious conceptual mistake, or hit a common pitfall? How do I effectively change directories and call a second makefile from within the first? My understanding was that simply calling make -f <name>
would be enough.
This is make/gmake 3.81 in bash.
make -f gtest-1.4.0/make/Makefile clean
you better say $(MAKE) -C gtest-1.4.0/make clean
. Why you haven't defined phony targets?
I'm not really too clear what you are asking, but using the -f
command line option just specifies a file - it doesn't tell make to change directories. If you want to do the work in another directory, you need to cd
to the directory:
clean:
cd gtest-1.4.0 && $(MAKE) clean
Note that each line in Makefile
runs in a separate shell, so there is no need to change the directory back.
Instead of the -f
of make
you might want to use the -C <path>
option. This first changes the to the path '<path>
', and then calles make
there.
Example:
clean:
rm -f ./*~ ./gmon.out ./core $(SRC_DIR)/*~ $(OBJ_DIR)/*.o
rm -f ../svn-commit.tmp~
rm -f $(BIN_DIR)/$(PROJECT)
$(MAKE) -C gtest-1.4.0/make clean
cd
cause the terminal to get into a infinite loop.
http://www.gnu.org/software/make/manual/make.html#Recursion
subsystem:
cd subdir && $(MAKE)
or, equivalently, this :
subsystem:
$(MAKE) -C subdir
.PHONY: db db: $(MAKE) -C db/ build start
It seems clear that $(TESTS)
is empty so your 1.4.0 makefile is effectively
all:
clean:
rm -f gtest.a gtest_main.a *.o
Indeed, all has nothing to do. and clean does exactly what it says rm -f gtest.a ...
wildcard
and a patsubst
, however these are returning empty from the main makefile, because the directory is not being effectively changed. Good eye.
Success story sharing
cd
'ing to thegtest-1.4.0
dir, you should use the-C
option ofmake
.&&
between the cd and make command. Otherwise if the cd fails it will still runmake clean
... in the wrong directory!! Also you should always ONLY use$(MAKE)
, never the barewordmake
, when recursing. So something like:cd gtest-1.4.0 && $(MAKE) clean
-C
is not in the spec-C
is in the spec: gnu.org/software/make/manual/make.html#Recursion