meaning of "all-before" and "all-after" in makefiles - makefile

.PHONY: all all-before all-after clean clean-custom
all: all-before ../Flock.exe all-after
Since it's in .PHONY, it must be a Makefile keyword, but I don't know what it means or even does.

They are not keywords, they are referring to rules that are named all-before and all-after such that the former is invoked before building the executable and the latter is invoked right after. They are mentioned in the .PHONY because these are not filenames.
Bad example:
all: all-before binary all-after
binary:
gcc input.c -o binary
all-before:
-mkdir bin
all-after:
-cp binary bin

I don't think that's a makefile keyword. It's probably the name of another target defined somewhere else in the makefile (but I can't be sure without more context of the file).

They are just pre-inserted targets to get customization done.
See the code added to makefile and use that modified makefile.win
Processing makefile...
Makefile Processor: C:\Program Files (x86)\Dev-Cpp\MinGW32\bin\mingw32-make.exe
Command: mingw32-make.exe -f "MakefileMy.win"
----> added lines below
.PHONY: all all-before all-after clean clean-custom
all-before:
#echo " all before"
all-after:
#echo "all after done"
all: all-before $(BIN) all-after
--> partial compile.log file from DevC on Windows 10 machine:
all
" all before"
"all after done"
Compilation results...
Errors: 0
Warnings: 0

Related

How to make a recursive make evaluate sub-directory pre-requisites?

Appreciating that the title is not quite on "target", how can I make it so that when I call make at the top level, it will recursively call the makefiles in the sub-directories?
Having been intrigued by the Kconfig pattern, to learn it, I've applied it to a mark down to pdf generator.
The recursive Makefile resides in ./scripts/Makefile.boilerplate and is defined:
HEADER=$(wildcard section-header.md)
.PHONY:all clean $(md-sub-y)
all clean: $(md-sub-y)
all: $(TARGET)
clean:
# $(RM) $(TARGET)
$(TARGET): $(HEADER) $(md-y) | $(md-sub-y)
# cat /dev/null $^ > $#
$(md-sub-y):
# $(MAKE) -C $(#D) TOPDIR=$(TOPDIR) $(MAKECMDGOALS)
I'm likely using the order-only prerequisite for the $(TARGET) target inappropriately, but it solved a minor problem.
In each directory there is a unique KConfig file (not shown), which lists CONFIG_{OPTION} macros that evaluate to either y or n. Then each directory contains a Makefile that has the form:
include Kconfig
md-$(CONFIG_INTRODUCTION)+= Introduction.md
md-$(CONFIG_FW_UPDATE)+= FW-update.md
md-sub-$(CONFIG_CHAPTERS)+= Chapters/Chapters.md
md-$(CONFIG_CHAPTERS)+= Chapters/Chapters.md
md-$(CONFIG_EXAMPLES)+= Examples.md
md-$(CONFIG_APPENDIX_I)+= Appendix-I.md
md-$(CONFIG_APPENDIX_II)+= Appendix-II.md
md-$(CONFIG_APPENDIX_III)+= Appendix-III.md
include ${TOPDIR}/scripts/Makefile.boilerplate
And finally, the very top level makefile is (abbreviated):
.PHONY: all clean pdf embedded_html
all clean test: JsonAPI/JsonAPI.md
all: pdf embedded_html
pdf: $(MARKDOWN_FILES:.md=.pdf)
embedded_html: $(MARKDOWN_FILES:.md=.html)
MAKEFLAGS += --no-print-directory
clean:
# $(RM) *.pdf *.html
JsonAPI/JsonAPI.md:
# $(MAKE) -C $(#D) TOPDIR=${CURDIR} $(MAKECMDGOALS)
%.html:%.md
# pandoc -s --toc -c /var/www/css/bootstrap.css $< -f markdown -t html -s -o $#
%.pdf:%.md
# pandoc --read=markdown --table-of-contents --toc-depth=3 --preserve-tabs --standalone --template=template.latex $(PANDOC_ENGINE)=pdflatex --listings -V geometry:margin=1in --highlight-style=pygments -H listing-setup.tex -r markdown+simple_tables+table_captions+yaml_metadata_block $< -o $#
If I call make on an unbuilt directory tree, it works fine. But there are a few problems I'm not sure how to address:
How can I ensure that if an updated .md deeply nested in the directory tree will cause the top level PDF file to be updated? Or, How can I force the makefile's in the sub-directories to be called?
The clean target at the top level is problematic, in that it doesn't recurse through the sub-directories. What do I need to do to remedy that?
Is there a better way to include the Makefile.boilerplate makefile, without having to define the TOPDIR on the $(MAKE) command line as I've done?
For 1, and 2, I'm guessing that an empty target dependency (FORCE:) will be required. And for 3, I've tried using $(CURDIR) but it was always evaluating to the directory the Makefile resided in, not the parent directory where the original make command was invoked.
Changing the md-sub-$(CONFIG_EEEE) macro definition to be just the directory was the key, and to make those targets have an empty rule.
Essentially, the per directory Makefile from above becomes:
include Kconfig
md-$(CONFIG_INTRODUCTION)+= Introduction.md
md-$(CONFIG_FW_UPDATE)+= FW-update.md
md-sub-$(CONFIG_CHAPTERS)+= Chapters/Chapters.md
md-$(CONFIG_CHAPTERS)+= Chapters
md-$(CONFIG_EXAMPLES)+= Examples.md
md-$(CONFIG_APPENDIX_I)+= Appendix-I.md
md-$(CONFIG_APPENDIX_II)+= Appendix-II.md
md-$(CONFIG_APPENDIX_III)+= Appendix-III.md
include ${TOPDIR}/scripts/Makefile.boilerplate
and the default Makefile.boilerplate changes the $(md-sub-y) target too:
$(md-sub-y): FORCE
# $(MAKE) -C $# TOPDIR=$(TOPDIR) $(MAKECMDGOALS)
FORCE:
And the top level makefile no longer needs $(#D) on the command line for the JsonAPI recipe, just $#.

Makefile does not recognize pattern rule

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.

GNU Make Skipping Straight to Linking

I have a makefile that for various reasons relies on a supporting python script to run every time and grab files from several external locations, copy into working directory, and run through a separate preprocessor before compiling.
This makefile must be able to be run in parallel (-j8) so the order of processing cannot be guaranteed.
In trying to explicitly specify prerequisites, I have created a situation where make skips all object files, goes straight to linking, and fails because the necessary objects do not exist. On a second run, all the objects already exist (the preprocess step skips the files that already exist) and all the files are compiled and linked properly.
When run without -j# everything works fine, but the moment I add -j2, the skipping begins.
Following is an example make file:
GEN_FILES := file1.cpp file2.cpp file3.cpp
CXX_FILES := bin_main.cpp $(GEN_FILES)
OBJ_FILES := $(patsubst %.cpp,%.o,$(CXX_FILES))
.PHONY : all clean prepare
all : bin_file
prepare :
# Copy and preprocess all source files
[ -f file1.cpp ] || cp d1/file1.cpp .
[ -f file2.cpp ] || cp d2/file2.cpp .
[ -f file3.cpp ] || cp d3/file3.cpp .
$(OBJ_FILES) : prepare
bin_file : $(OBJ_FILES)
[ -f file1.o ] && [ -f file2.o ] && [ -f file3.o ] && touch bin_file
%.o : %.cpp
#echo "Compiling $<..."
[ -f $< ] && touch $#
clean :
$(RM) *.o
$(RM) file*
$(RM) bin_file
How can I get this to build in one go, first running prepare to collect all files and then compiling and linking as necessary?
As code_fodder mentions the issue is the creation of the source files.
Basically what happens is, you have not told make how to create these source files, so as far as make knows they don't exist and there's no way to create them. So when make wants to build, for example, file1.o it looks at your pattern rule and finds it could build file1.o from file1.cpp. So then it looks for how to build file1.cpp. No file1.cpp exists, and there is no rule that make knows of that will build it, so make ignores that pattern rule as not matching.
Then make sees the target:
$(OBJ_FILES) : prepare
so it thinks there's no recipe needed to create the object files, and just runs the link line. The next time through, make sees the prepared source files (from the previous build) and then it can use your pattern rule.
If you change your pattern rule to a static pattern rule, where you explicitly tell make exactly what rule to use instead of providing it with a possible rule to use that it can ignore if it doesn't match (which is what a pattern rule is), you'll see the error:
$(OBJ_FILES): %.o : %.cpp
#echo "Compiling $<..."
sleep 1
[ -f $< ] && touch $#
will tell you:
make: *** No rule to make target 'file1.cpp', needed by 'file1.o'. Stop.
Remember, make is looking for a matching pattern rule BEFORE it actually builds anything: it doesn't want to build every possible prerequisite of every possible matching pattern rule, to decide whether or not at the end of it the rule can be used. The rule is matched based on the current state of the filesystem plus rules you have given make about changes it could make. Make has no idea that if it were to invoke the prepare target the source files it was looking for would magically come into existence.
Your basic problem is that this statement is the wrong dependency relationship:
$(OBJ_FILES) : prepare
It's not really true that the object files depend on prepare; what's true is that the PREPARED SOURCE FILES depend on prepare. The object files depend only the "prepared" source files, as your pattern rules shows. This rule should be written, instead:
$(GEN_FILES): prepare
If you do this with -j everything will wait as you want.
Yeah, this gets messy / difficult. The problem you have is that you can specify prerequisite lists - that can work in order, but as soon as you start to use -j then make can start processing prerequisites in any old order. So bin_file requires $(OBJ_FILES) which require prepare. Then %.o requires the same named %.cpp file - which it can do for main.o, but not the filex.o since they don't exist yet - but it tries anyway and fails - in the mean time make (in parallel) is potentially starting to generate the .cpp files, but by this time its too late...etc...
My Prerequisites Build Pattern
I use a very specific prerequisites pattern of my own design - some might frown upon - but I have carefully considered this over the years and found it to be optimal for me.
I create a rule called build or something - which requires build_prerequisites target and then calls make to do the actual build once this is complete:
.PHONY: build
build: build_prerequisites
build:
#echo "start_build"
#$(MAKE) bin_file
This means that build_prerequisites is always run first before the recipe runs. You cant seem to achieve the same forcing of order (at least not easily) using just dependencies. I.e. a list of dependencies can be run in any order with -j, but the rule recipe is always run last.
Now we have this pattern we can fill in the rest. First the build_prerequisites target which does your file generation - I am using echo in my example because I don't have your python script:
.PHONY: build_prerequisites
build_prerequisites:
#echo "build_prerequisites"
echo "create file1" > file1.cpp
echo "create file2" > file2.cpp
echo "create file3" > file3.cpp
Finally add in the c++ compile and link stages - these will be run with the single recursive make call from build - i.e. $(MAKE) bin_file (again I am using echo to create the files in my example):
%.o : %.cpp
#echo "compiling: $<"
##echo "$(CXX) $(SRC_INCLUDES) $(LIB_INCLUDES) $(CXXFLAGS) -c $< -o $#"
#echo "touch" > $#
bin_file : $(OBJ_FILES)
#echo "linking: $<"
#echo $(CXX) $(SRC_INCLUDES) $^ $(LIB_INCLUDES) $(LDFLAGS) -o $#
#echo "touch" > $#
Output
Here is the output from my test program (using echo) and main.cpp already exists usingn -j10:
make -j10
build_prerequisites
echo "create file1" > file1.cpp
echo "create file2" > file2.cpp
echo "create file3" > file3.cpp
start_build
make[1]: Entering directory '/mnt/d/software/ubuntu/make'
compile: bin_main.cpp
compile: file1.cpp
compile: file2.cpp
compile: file3.cpp
link: bin_main.o
g++ bin_main.o file1.o file2.o file3.o -o bin_file
make[1]: Leaving directory '/mnt/d/software/ubuntu/make'
Note: if I put a sleep 1 in the "compile" rule - this still takes only 1 second for all 4 files to compile.
Put it all together
GEN_FILES := file1.cpp file2.cpp file3.cpp
CXX_FILES := bin_main.cpp $(GEN_FILES)
OBJ_FILES := $(patsubst %.cpp,%.o,$(CXX_FILES))
###### STAGE 1
.PHONY: build
build: build_prerequisites
build:
#echo "start_build"
#$(MAKE) bin_file
.PHONY: build_prerequisites
build_prerequisites:
#echo "build_prerequisites"
copy_and_pp_files.py $(CXX_FILES) $(SEARCH_DIRS) .
copy_and_pp_files.py $(CFG_FILES) $(SEARCH_DIRS) .
###### STAGE 2
%.o : %.cpp
#echo "compiling: $<"
#$(CXX) $(SRC_INCLUDES) $(LIB_INCLUDES) $(CXXFLAGS) -c $< -o $#
bin_file : $(OBJ_FILES)
#echo "linking: $<"
#$(CXX) $(SRC_INCLUDES) $^ $(LIB_INCLUDES) $(LDFLAGS) -o $#
###### OTHER RULES
.PHONY: clean
clean :
#$(RM) *.o
#$(RM) file*
I have attempted to use your actual code, but I have no way to test this so there may be a bug in there. I split it up into 2 "stages" for clarity. Stage 1 is done in your makeor make build call, then state 2 is done in the recursive make call in the build recipe.

Makefile stops running at the middle [duplicate]

Hopefully this is a very simple question. I have a makefile pattern rule that looks like this:
%.so : %.f %.pyf
f2py -c -L${LAPACK_DIR} ${GRASPLIBS} -m $* $^ ${SOURCES} --opt='-02' --f77flags='-fcray-pointer' >> silent.txt
I want the makefile to build a number of .so files, so I tried to get it to build two files (radgrd_py.so and lodiso_py.so) by doing this:
radgrd_py.so lodiso_py.so:
%.so : %.f %.pyf
f2py -c -L${LAPACK_DIR} ${GRASPLIBS} -m $* $^ ${SOURCES} --opt='-02' --f77flags='-fcray-pointer' >> silent.txt
and then tried this:
radgrd_py.so:
lodiso_py.so:
%.so : %.f %.pyf
f2py -c -L${LAPACK_DIR} ${GRASPLIBS} -m $* $^ ${SOURCES} --opt='-02' --f77flags='-fcray-pointer' >> silent.txt
But in each case, it only builds the first target that I specify. If I run 'make radgrd_py.so' it works fine, I'm just not sure how to specify a list of files that need to be built so I can just run 'make'.
The usual trick is to add a 'dummy' target as the first that depends on all targets you want to build when running a plain make:
all: radgrd_py.so lodiso_py.so
It is a convention to call this target 'all' or 'default'. For extra correctness, let make know that this is not a real file by adding this line to your Makefile:
.PHONY: all
Best way is to add:
.PHONY: all
.DEFAULT: all
all: radgrd_py.so lodiso_py.so
Explanations:
make uses the first target appearing when no .DEFAULT is specified.
.PHONY informs make that the targets (a coma-separated list, in fact) don't create any file or folder.
all: as proposed by schot

Calling other makefile from make

I have seen this question and am somehow still unable to get make to properly call another Makefile. Here is my Makefile:
base:
cd Base && $(MAKE)
Base is a sub-directory of my current directory where there is a different Makefile used to compile the files in said folder. However, when I call make, I simply get nothing to be done for base, whereas when I do cd Base && make from the command-line, I get expected behavior (i.e., compilation occurs). In case it is something wrong with the Makefile in Base, here is a copy of that as well:
CC=g++
CFLAGS=-O3 -Wall -pedantic -Werror -c
LINK=g++
LFLAGS=-O3
SRC=main.cpp
OBJ=..\lib\main.o
EXE=..\bin\test.exe
all: $(EXE)
$(EXE): $(OBJ) $(SRC)
$(LINK) $(LFLAGS) $(OBJ) -o $(EXE)
..\lib\main.o: main.cpp
$(CC) $(CFLAGS) $< -o $#
I'm not sure what $(MAKE) amounts to (I'm assuming just 'make'), but I have my makefiles setup in a cascading manner where one calls another in order to cover all subdirectories.
Each makefile has some common targets like 'all' and 'clean'.
Then my makefiles which are just delegating to subdirs look something like this:
.PHONY : all
all:
cd SubDir1 && make $#
cd SubDir2 && make $#
...
.PHONY : clean
clean:
cd SubDir1 && make $#
cd SubDir2 && make $#
...
$# is an automatic variable which will be substituted for the target ('all' or 'clean' in the example above).
This allows you to run 'make', 'make clean', 'make all', or even 'make clean all' from the top-level dir and it will recurse through the subdirs specified in the makefiles for the appropriate target. So if you run 'make clean' at the top, all directories in the makefile's list will be called with 'make clean'.
You can still use this technique even if you don't have common targets. Simply change the automatic variable $# with the appropriate target for each directory's makefile.

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