Multiple directories in Makefile target path, $# only contains top directory - makefile

I have this target in my Makefile, BUILD and SOURCE are directory paths.
$(BUILD)/%.o: $(SOURCE)/%.c
#echo "In target: "'(BUILD)/%.o: (SOURCE)/%.c'
#echo "(BUILD) = $(BUILD)"
#echo " # = $#"
#echo " (#D) = $(#D)"
#echo " (#F) = $(#F)"
gcc -o $# $< $(CFLAGS)
I added these echo commands to make it clear where my confusion is - now here's the output when I try to run this:
In target: (BUILD)/%.o: (SOURCE)/%.c
(BUILD) = build/debug
# = build/main.o
(#D) = build
(#F) = main.o
gcc -o build/main.o source/main.c -c -Iinclude -g
So, why aren't $#, $(#D), or $(#F) acting as I would expect them to? Shouldn't $# be build/debug/main.o since that's the actual target?

There is only one possible way this can happen, assuming the example above is accurate.
When you defined the rule, the value of the BUILD variable must have been build. Then sometime after the rule was defined, you changed the value of the BUILD variable to build/debug. Maybe you did this directly, or maybe you did it through a target-specific variable. But that's the only way you can get the results you've shown us given that rule.

Related

Wildcard Pattern Matching in Make

Here is my project structure.
| - src
| - boot
| - table.s
| - boot.s
| - machine
| - revb
| - memmap
| - vars.s
| - os
| - utils
| - ...lots here
I am grouping features by folder, and have a special folder for machine specific code, link scripts, anything.
The problem I am having with make is that I can't seem to get the Pattern match to work.
The below runs and builds the .o files.
#This gets repetative as every file needs to have a recipe by itself.
$(TARGET_DIR)/hash.o : $(SRC_DIR)/utils/hash.s machine
#echo "compiling $<"
$(CC) $(CFLAGS) $< -o $#
#echo "assembly dump $#"
$(DUMP) -D $# > $#.list
The below does NOT work. It doesn't run any of the commands.
#if this works that would be perfect every folder/file will be a recipe!
$(TARGET_DIR)/%.o : $(SRC_DIR)/%.s machine
#echo "compiling $<"
$(CC) $(CFLAGS) $< -o $#
#echo "assembly dump $#"
$(DUMP) -D $# > $#.list
Nothing runs at all, For some reason no files seem to match that pattern.
I have also tried this.
# if this works, it would be a bit annoying as this is per feature recipe/target.
$(TARGET_DIR)/%.o : $(SRC_DIR)/boot/%.s machine
#echo "compiling $<"
$(CC) $(CFLAGS) $< -o $#
#echo "assembly dump $#"
$(DUMP) -D $# > $#.list
Edit
full makefile for reference
CFLAGS = -march=rv32i -mabi=ilp32
CC = riscv32-unknown-linux-gnu-as
LINKER = riscv32-unknown-linux-gnu-ld
DUMP = riscv32-unknown-linux-gnu-objdump
COPY = riscv32-unknown-linux-gnu-objcopy
SRC_DIR = src
TARGET_DIR = target
MACHINE_FILES_DIR = machine
TARGET_MACHINE = revb
# vizoros : $(TARGET_DIR)/%.o
# $(LINKER) $(TARGET_DIR)/boot.o $(TARGET_DIR)/table.o $(TARGET_DIR)/os.o $(TARGET_DIR)/hash.o -T $(TARGET_DIR)/memmap -o $(TARGET_DIR)/$#.elf
# $(DUMP) -D $(TARGET_DIR)/$#.elf > $(TARGET_DIR)/$#.list
$(TARGET_DIR)/%.o : $(SRC_DIR)/boot/%.s machine
#echo "compiling $<"
$(CC) $(CFLAGS) $< -o $#
#echo "assembly dump $#"
$(DUMP) -D $# > $#.list
machine: folders
cp -r $(SRC_DIR)/$(MACHINE_FILES_DIR)/$(TARGET_MACHINE)/. $(TARGET_DIR)
folders:
mkdir -p $(TARGET_DIR)
.phony: clean
clean:
rm -rf $(TARGET_DIR)
As with your other question, you are expecting too much fancy capability from make. Make is a very simple tool. It will not go looking around your directories for files that could be built. It will build only exactly what you ask it to build. It will not infer matching files based on heuristics: it will match only exact strings.
Make always works backwards: it starts with the final target you ask it to build and finds a rule that can build that. Then it looks at each of the prerequisites of that final target and finds a rule that can build each one of those. Then it looks at any prerequisites of each of the prerequisites of those, etc. Once it has built (or found source files for) all the prerequisites of a target, it builds that target, then walks back up until finally it builds the final target you asked for.
In your makefile above you've commented out the "final target" you want built (vizoros), so of course make will not build it.
I'm just going to give you a makefile that solves your problem... if you want to understand what it does please consult the GNU make manual. Note I haven't actually tried this, I just wrote it here. Also note I omitted the whole machine thing because I don't understand what it's supposed to do and you didn't really define it.
CFLAGS = -march=rv32i -mabi=ilp32
CC = riscv32-unknown-linux-gnu-as
LINKER = riscv32-unknown-linux-gnu-ld
DUMP = riscv32-unknown-linux-gnu-objdump
COPY = riscv32-unknown-linux-gnu-objcopy
SRC_DIR = src
TARGET_DIR = target
MACHINE_FILES_DIR = machine
TARGET_MACHINE = revb
# Find all .s files under SRC_DIR
SRCS := $(shell find $(SRC_DIR) -name \*.s)
# Use VPATH with a list of directories to be searched for
VPATH := $(sort $(dir $(SRCS)))
# Convert all .s files into .o files directly under TARGET_DIR
# First strip off the directory, then convert
OBJS := $(patsubst %.s,$(TARGET_DIR)/%.o,$(notdir $(SRCS)))
# Define the final target and provide all the object files as prerequisites
$(TARGET_DIR)/vizoros.elf : $(OBJS)
mkdir -p $(#D)
$(LINKER) $^ -T $(TARGET_DIR)/memmap -o $#
$(DUMP) -D $# > $(#:.elf=.list)
# Define a pattern rule to build an object file in TARGET_DIR
# The source file will be searched for via VPATH
$(TARGET_DIR)/%.o : %.s
mkdir -p $(#D)
#echo "compiling $<"
$(CC) $(CFLAGS) -c $< -o $#
#echo "assembly dump $#"
$(DUMP) -D $# > $#.list
# It must be .PHONY, not .phony: make, like all POSIX tools, is
# case-sensitive
.PHONY: clean
clean:
rm -rf $(TARGET_DIR)
References:
GNU make manual
= vs := variables
shell function
dir and notdir functions
sort and patsubst functions
VPATH
Substitution references
Automatic variables
Phony targets
Also note you had an error in your compile command; you were missing the -c option which tells the compiler to generate an object file rather than a final executable file.

Multiple Targets Not Being Executed By Makefile

I'm updating the title and content here to make it clear that this particular question was asking something that I didn't see answered plainly elsewhere. The key notion is understanding that something that looks like a single target doing multiple things in a Makefile is actually multiple targets doing one thing each.
I will also remove some extraneous material since that ended up not being relevant.
Original Content
My problem is that I have a Makefile that is (apparently) not calling one of my sub-directory Makefiles correctly. I have a project structure like this:
quendor
src
cheap
cheap_init.c
Makefile
zmachine
main.c
Makefile
Makefile
The Makefile in the project root will refer to the Makefiles in the individual directories. Here is that core Makefile:
CC ?= gcc
CFLAGS += -Wall -std=c99
CFLAGS += -D_POSIX_C_SOURCE=200809L
CFLAGS += -O2 -fomit-frame-pointer
RANLIB ?= $(shell which ranlib)
AR ?= $(shell which ar)
export CC
export AR
export CFLAGS
export RANLIB
SRC_DIR = src
ZMACHINE_DIR = $(SRC_DIR)/zmachine
ZMACHINE_LIB = $(ZMACHINE_DIR)/quendor_zmachine.a
CHEAP_DIR = $(SRC_DIR)/cheap
CHEAP_LIB = $(CHEAP_DIR)/quendor_cheap.a
SUB_DIRS = $(ZMACHINE_DIR) $(CHEAP_DIR)
SUB_CLEAN = $(SUB_DIRS:%=%-clean)
$(SUB_DIRS):
#echo $(SUB_DIRS) # src/zmachine src/cheap
#echo "DIR:"
#echo $# # src/zmachine
$(MAKE) -C $#
$(SUB_CLEAN):
-$(MAKE) -C $(#:%-clean=%) clean
clean: $(SUB_CLEAN)
help:
#echo "Quendor"
.PHONY: $(SUB_DIRS) $(SUB_CLEAN) clean help
A key problem for me is this bit from the above:
$(SUB_DIRS):
#echo $(SUB_DIRS) # src/zmachine src/cheap
#echo "DIR:"
#echo $# # src/zmachine
$(MAKE) -C $#
I put the echo statements in just to show what's happening. Notice the $SUB_DIRS is correctly showing both directories, but when the Makefile runs it only shows src/zmachine. (The comments there indicate what I see during runtime.) The Makefile (apparently) doesn't process src/cheap.
The full output of the Makefile running is this (the first three lines there being my echo statements):
src/zmachine src/cheap
DIR:
src/zmachine
/Applications/Xcode.app/Contents/Developer/usr/bin/make -C src/zmachine
cc -Wall -std=c99 -D_POSIX_C_SOURCE=200809L -O2 -fomit-frame-pointer -fPIC -fpic -o main.o -c main.c
ar rc quendor_zmachine.a main.o
/usr/bin/ranlib quendor_zmachine.a
** Done with Quendor Z-Machine.
The only thing I could think of initially was that perhaps after running the sub-makefile in src/zmachine, the Make process was either erroring out or thinking it was done. But the $(SUB_DIRS) part should have iterated through both directories, I would have thought.
So I'm a bit stuck as to how to proceed.
Extra Note: The "I would have thought" part of what I said was where I was incorrect. $(SUB_DIRS) was not being executed as I thought it was; the accepted answer has clarified this.
The way make works is, if you don't provide an argument, it will start by scanning the Makefile looking for the "default goal". The default goal is simply the first target it encounters (notice it's the first target, not targets).
In your case, the rule:
$(SUB_DIRS):
$(MAKE) -C $#
Is equivalent to:
src/zmachine src/cheap:
$(MAKE) -C $#
Which is equivalent to:
src/zmachine:
$(MAKE) -C $#
src/cheap:
$(MAKE) -C $#
So the first target make encounters is src/zmachine, and that's its default goal and the one that gets processed. The way to fix this is, as user657267 said in the comments, to add one target that you know will be processed first that would have the other targets (that you really want to build) as its prerequisites.

make: *** No rule to make target - gfortran

I am trying to compile a code -
this code uses a few libraries and for starters I am trying to create a makefile to get one library
I am having difficulties.
this is the makefile
HOME = $(shell pwd)
LIBNA = libbv.a
LIBZP = $(HOME)/$(LIBNA)
# FFLAGC = -Mextend -Msave -g -C -Mchkfpstk -Mchkptr -fpic -Ktrap=fp
FC = gfortran
ifeq ($(OSTYPE),linux)
FC = pgf95 -Msave -fpic
endif
# per il gfortran
FFLAGC = -g -Wall-ffixed-line-length-0 -Mextend -Msave -g -C -Mchkfpstk -Mchkptr -fpic -Ktrap=fp
# FC = gfortran
#
SOURCE = \
filename1.f\
filename2.f\
...
filenamen.f
.SUFFIXES: .f
OBJ = $(SRCS:.f=.o)
.f.o:
$(FC) $(FFLAG) -c $< $#
$(LIBZP): $(LIBZP)($(OBJ))
ar -r $(LIBZP) $?
rm -f $?
this is the makefile I am using.
I get the error
make: *** No rule to make target absolutepath/libbv.a()', needed by
absolute_path/libbv.a'. Stop.
I was wondering if any of you can help
Well, your error message shows this:
absolutepath/libbv.a()
with nothing inside the parentheses. But your makefile has this:
$(LIBZP): $(LIBZP)($(OBJ))
with $(OBJ) in the parentheses. So clearly, $(OBJ) is expanding to the empty string. Why is that?
Well, OBJ is set here:
OBJ = $(SRCS:.f=.o)
based on SRCS. Well, what does that variable contain?
Aha. Nothing, because it's never set. You set this though:
SOURCE = \
...
SOURCE != SRCS, so you're modifying an empty variable and OBJ is the empty string.
I'm not sure why you're prefixing the target with the current directory... that's where it will go by default if you don't specify any directory. In any event, you can use $(CURDIR) rather than running $(shell pwd).
If you're going to use GNU make anyway, I recommend you use pattern rules rather than suffix rules: they're much simpler to read/understand:
%.o : %.f
$(FC) $(FFLAG) -c $< $#
Also don't you need a -o here before $#? I don't use Fortran compilers but I would imagine they work more or less the same as C/C++ compilers.

Makefile is skipping certain dependencies

So I am writing a makefile that will take some files (*.in) as input to my C++ program and compare their output (results.out) to given correct output (*.out).
Specifically I have files t01.in, t02.in, t03.in, t04.in, and t05.in.
I have verified that $TESTIN = t01.in t02.in t03.in t04.in t05.in.
The problem is that it seems to run the %.in: %.out block only for three of these files, 1,3, and 4. Why is it doing this?
OUTPUT = chart
COMPILER = g++
SOURCES = chart.cpp
HEADERS =
OBJS = $(SOURCES:.cpp=.o)
TESTIN = tests/*.in
all: $(OUTPUT)
$(OUTPUT): $(OBJS)
$(COMPILER) *.o -o $(OUTPUT)
%.o: %.cpp
clear
$(COMPILER) -c $< -o $#
test: $(TESTIN)
%.in: %.out
./$(OUTPUT) < $# > tests/results.out
printf "\n"
ifeq ($(diff $< tests/results.out), )
printf "\tTest of "$#" succeeded for stdout.\n"
else
printf "\tTest of "$#" FAILED for stdout!\n"
endif
Additionally, if there is a better way of accomplishing what I am trying to do, or any other improvements I could make to this makefile (as I am rather new at this), suggestions would be greatly appreciated.
EDIT: If I add a second dependency to the block (%.in: %.out %.err), it runs the block for all five files. Still no idea why it works this way but not the way before.
First, I don't see how TESTIN can be correct. This line:
TESTIN = tests/*.in
is not a valid wildcard statement in Make; it should give the variable TESTIN the value tests/*.in. But let's suppose it has the value t01.in t02.in t03.in t04.in t05.in or tests/t01.in tests/t02.in tests/t03.in tests/t04.in tests/t05.in, or wherever these files actually are.
Second, as #OliCharlesworth points out, this rule:
%.in: %.out
...
is a rule for building *.in files, which is not what you intend. As for why it runs some tests and not others, here is my theory:
The timestamp of t01.out is later than that of t01.in, so Make decides that it must "rebuild" t01.in; likewise t03.in and t04.in. But the timestamp of t02.out is earlier than that of t02.in, so Make does not attempt to "rebuild" t02.in; likewise t05.in. The timestamps of t02.err and t05.err are later than those of t02.in and t05.in, respectively, so when you add the %.err prerequisite, Make runs all tests. You can test this theory by checking the timestamps and experimenting with touch.
Anyway, let's rewrite it. We need a new target for a new rule:
TESTS := $(patsubst %.in,test_%,$(TESTIN)) # test_t01 test_t02 ...
.PHONY: $(TESTS) # because there will be no files called test_t01, test_t02,...
$(TESTS): test_%: %.in %.out
./$(OUTPUT) < $< > tests/results.out
Now for the conditional. Your attempted conditional is in Make syntax; Make will evaluate it before executing any rule, so tests/result.out will not yet exist, and variables like $< will not yet be defined. We must put the conditional inside the command, in shell syntax:
$(TESTS): test_%: %.in %.out
./$(OUTPUT) < $< > tests/results.out
if diff $*.out tests/results.out >/dev/null; then \
echo Test of $* succeeded for stdout.; \
else echo Test of $* FAILED for stdout!; \
fi
(Note that only the first line of the conditional must begin with a TAB.)

Change Makefile variable value inside the target body

Is there a way to reassign Makefile variable value inside of the target body?
What I am trying to do is to add some extra flags for debug compilation:
%.erl: %.beam
$(ERLC) $(ERLFLAGS) -o ebin $<
test: clean debug_compile_flag compile compile_test
debug_compile:
$(ERLCFLAGS) += -DTEST
So if I invoke test target I would like to clean up my environment, add some new flags (like -DTEST to the existing ones), compile the whole code once again (first sources, then test modules).
I do not want to copy/paste the code for compiling with some new flags set since there is a lot of logic put here and there.
Is there some easy way to redefine the variable value so I can reuse the existing code?
Yes, there is an easy way to do it, and without rerunning Make. Use a target-specific variable value:
test: clean debug_compile
debug_compile: ERLCFLAGS += -DTEST
debug_compile: compile compile_test;
Another answer is here: Define make variable at rule execution time.
For the lazy, you can have rules like the following (FLAG and DEBUG are my variables):
.DBG:
$(eval FLAG += $(DEBUG))
Here is the solution I use:
PASSWORD = abc123
main: sub
#echo "in main" $(PASSWORD)
sub:
#echo "in sub" $(PASSWORD)
$(eval PASSWORD=qwerty)
#echo "in sub" $(PASSWORD)
If you run make main then the output is:
in sub abc123
in sub qwerty
in main qwerty
You can see that the original value "abc123" is overwritten in the sub and the new value "qwerty" is visible at the main level.
To override on the command line try something like:
make prefix=<path to new dir> install
This won't change Makefile, but will alter the variable.
I wanted to add a target in a makefile to run tests, which implied recompiling the source code with some debug flags. Ian's answer: https://stackoverflow.com/a/15561911/ was the only solution that worked.
Here's the Makefile I came up with, which guaranties the order of execution when running make tests:
TARGET = a.out
CC = g++
GENERIC_F = -Wall -Wextra -I. -Idoctest/doctest/
CFLAGS = -O0 -std=c++11 $(GENERIC_F)
DEBUG_MODE = -DDEBUG
LINKER = g++
LFLAGS = $(GENERIC_F) -lm
SRCDIR = src
OBJDIR = build
BINDIR = bin
SOURCES = $(wildcard $(SRCDIR)/*.cc)
INCLUDES = $(wildcard $(SRCDIR)/*.h)
OBJECTS = $(SOURCES:$(SRCDIR)/%.cc=$(OBJDIR)/%.o)
rm = rm -f
.PHONY: clear_screen tests extend_cflags
$(BINDIR)/$(TARGET): $(OBJECTS) $(INCLUDES)
$(LINKER) $(OBJECTS) $(LFLAGS) -o $#
#echo -e "Linking complete!\n"
$(OBJECTS): $(OBJDIR)/%.o : $(SRCDIR)/%.cc $(INCLUDES)
#mkdir -p $(OBJDIR) $(BINDIR)
$(CC) $(CFLAGS) -c $< -o $#
#echo -e "Compiled "$<" successfully!\n"
.PHONY: clean
clean:
#$(rm) $(OBJECTS)
#echo "Cleanup complete!"
.PHONY: remove
remove: clean
#$(rm) $(BINDIR)/$(TARGET)
#echo "Executable removed!"
clear_screen:
#clear
extend_cflags:
$(eval CFLAGS += $(DEBUG_MODE))
tests: | remove extend_cflags $(BINDIR)/$(TARGET) clear_screen
#$(BINDIR)/$(TARGET)
Edit: As explained by Beta in the other answer, it is possible.
No. There is no way to do this in the Makefile. You can however change the value of a variable on the make command line. If you rewrite your Makefile as follows:
ERLCFLAGS += $(ERLCFLAGSADDED)
%.erl: %.beam
$(ERLC) $(ERLCFLAGS) -o ebin $<
test: clean compile compile_test
Then, you can invoke make to perform your tests using:
make ERLCFLAGSADDED=-DTEST test

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