Makefile question.

[xz]

I am a rookie of C++ and got so confused with the Makefile these days.
Could anyone be so kind and give a little sample Makefile for the
following particular example?

Let's say I have the following files describing 4 classes (A, B, C1,
C2) and a test program (test.cpp) which runs a test for classes C1 and
C2.

A.h
A.cpp
B.h
B.cpp
C1.h
C1.cpp
C2.h
C2.cpp
test.cpp

The inhirentance relation among the 4 classes are as follows:

class C1: public B
class C2: public B
class B: public A

i.e. C1 and C1 are both dependent on B while B is dependent on A.

test.cpp depends on C1 and C2 and contains the main() function.

I am on a linux machine(Ubuntu 7.10) and use g++ 4.1 as the compiler.

Then how should I write the Makefile? Thanks a lot in advance!

 

[Victor Bazarov]

I am a rookie of C++ and got so confused with the Makefile these days.

Those have really nothing to do with each other. C++ language
Standard does not define 'Makefile', neither is 'Makefile' C++
specific.

Could anyone be so kind and give a little sample Makefile for the
following particular example?
[..]
I am on a linux machine(Ubuntu 7.10) and use g++ 4.1 as the compiler.

Then how should I write the Makefile? Thanks a lot in advance!

Go to 'gnu.*' or 'comp.os.linux.*' hierarchies.

V

 

[nullius.filius]

This might work (or might not). Makefiles are fiddly.

Where you see <tab> in the following lines, please
remove the characters "<tab>" and insert the actual
tab key from the keyboard. Makefiles use the tab key
for executable lines.

#%<----------------------------------
SRC= test.cpp C1.cpp C2.cpp B.cpp A.cpp
OBJ= $(SRC:.cpp=.o)
EXE= test
CC= g++
%.o: %.cpp
<tab>$(CC) -o $@ -c $<
..PHONY: all
all: $(EXE)
$(EXE): $(OBJ)
<tab>$CC $(OBJ) -o $(EXE)

 

[nullius.filius]

x-no-archive: yes
This might work (or might not). Makefiles are fiddly.

Where you see <tab> in the following lines, please
remove the characters "<tab>" and insert the actual
tab key from the keyboard. Makefiles use the tab key
for executable lines.

#%<----------------------------------
SRC= test.cpp C1.cpp C2.cpp B.cpp A.cpp
OBJ= $(SRC:.cpp=.o)
EXE= test
CC= g++
%.o: %.cpp
<tab>$(CC) -o $@ -c $<
..PHONY: all
all: $(EXE)
$(EXE): $(OBJ)
<tab>$CC $(OBJ) -o $(EXE)

 

[James Kanze]

Those have really nothing to do with each other. C++ language
Standard does not define 'Makefile', neither is 'Makefile' C++
specific.

Could anyone be so kind and give a little sample Makefile for the
following particular example?
[..]
I am on a linux machine(Ubuntu 7.10) and use g++ 4.1 as the compiler.
Then how should I write the Makefile? Thanks a lot in advance!

Go to 'gnu.*' or 'comp.os.linux.*' hierarchies.

Linux make is GNU make, and I believe that there's a special
mailing list for GNU make. Still, my advice would be:

-- If you're in a professional environment, use their standard
build tools, and don't worry about it. I've never seen a
standard environment where programmers had to write more
than a couple of lines of make, and those generally didn't
look much like a standard makefile either.

-- If you're working on your own, trying to learn C++, get an
IDE, and let it generate the makefiles for you. While the
IDE's that I've seen are pretty worthless (in fact, they're
rather counter-productive) for professional programming,
they're ideal for learning, and they allow you to
concentrate on one thing at a time: C++, for example, rather
than makefiles.

 

[Juha Nieminen]

If you are interested in making 'make' just work, without having to
know why it works, try this generic Makefile which I myself usually use
for everything:


# List source files (not headers!) and binary name:
# Use:
#SOURCES=file1.cc file2.cc file3.cc
# or:
SOURCES=$(wildcard *.cc)

BINARY=programname

# Set up compiler and compiler options:
CXX=g++
CXXFLAGS=-Wall -W -ansi -O3
LDLIBS=

# If you are compiling a C program (instead of C++), comment out
# this line:
LINK.o=$(LINK.cpp)


# --- No need to modify anything below this line ---
$(BINARY): $(SOURCES:.cc=.o)

..dep:
g++ -MM $(SOURCES) > .dep

-include .dep

 

[Juha Nieminen]

# List source files (not headers!) and binary name:
# Use:
#SOURCES=file1.cc file2.cc file3.cc
# or:
SOURCES=$(wildcard *.cc)

BINARY=programname

# Set up compiler and compiler options:
CXX=g++
CXXFLAGS=-Wall -W -ansi -O3
LDLIBS=

# If you are compiling a C program (instead of C++), comment out
# this line:
LINK.o=$(LINK.cpp)


# --- No need to modify anything below this line ---
$(BINARY): $(SOURCES:.cc=.o)

.dep:
g++ -MM $(SOURCES) > .dep

-include .dep

Forgot to tell: It can't know if your #include lines change in your
source files, so if you change them you'll have to "rm .dep" before
executing "make" so that it can update the dependencies.

 

[xz]

I understand the most simple (but kinda silly) way to write a Makefile
is to simply put all related the cpp files after the colon and compile
them all, like this:

testprogram: A.cpp B.cpp C1.cpp C2.cpp test.cpp
<Tab>g++ $? -o $@

However, the wierd thing that I came across was:
Every time I run "make testprogram" for the first time, the compiler (g
++) complaines that it cannot find the definitions of some member
functions, which I have defined in A.cpp or B.cpp

(Of course I hvae included C1.h and C2.h in test.cpp, included B.h in
C1.h, and included A.h in B.h.)

And, if I run "make testprogram" again (for the second time), then
they all compile well and the executable is just made there in good
state.

Anybody knows why that is happening?
I am using emacs and the running the compile command "make
testprogram" within emacs, I am not sure if that matters.

 

[Victor Bazarov]

I understand the most simple (but kinda silly) way to write a Makefile
is to [.. problems using 'g++' and 'make' ..]

Anybody knows why that is happening?
I am using emacs and the running the compile command "make
testprogram" within emacs, I am not sure if that matters.

Somebody knows. But this is the wrong newsgroup to ask about it.
Please try 'gnu.*' hierarchy or the newsgroup for your platform.
'make' or 'emacs' are not part of C++ _language_ and as such are
off-topic here. 'g++' has its own newsgroup.

V