C++ makefile error

Question

When I build a project usng Eclipse I get the following error regarding the Makefile:µ

Type make: *** No rule to make target `hello.exe', needed by `all'.  Stop.

My Makefile is this:

all: hello

hello: main.o factorial.o hello.o
   g++ main.o factorial.o hello.o -o hello

main.o: main.cpp
   g++ -c main.cpp

factorial.o: factorial.cpp
   g++ -c factorial.cpp

hello.o: hello.cpp
   g++ -c hello.cpp

clean:
   rm -rf *o hello

Does anyone know which is my mistake? Thank you in advance.

Answer 1

1st, good luck developing with Eclipse, you need a lot of Zen for that

2nd, a quick recap about how to read a makefile:

target: requiredTarget(optional)
 how to generate the target

so, as you can see, reading the first line of your makefile is like saying: " I have a target named all and this target requires the target hello in order to be generated ".

Now the target all is a special one, it's the one that is implicit, so when you or your IDE just type make in your shell make all is implied ( of course you can specify your target with make , the special case is just applied when no building target is specified via the command line ).

The chain begins with make or an explicit make all that always leads to build the all target, the all target calls in the hello target but since you are on Windows, the suffix .exe is automatically added and your make can't find a target named hello.exe .

Basically you need to manage your OS specific building steps and you have to edit that makefile to let this work, or you can wait for someone that is more into Eclipse to see if there is a good makefile-related option to manage this platform-specific stuff.

a good introduction is http://www.cprogramming.com/tutorial/makefiles.html

consider QTcreator for C++ developing.

Answer 2

I don't have idea about Eclipse but whatever the Makefile you have will work fine in Linux. try to change target name after all like this and check out

all: hello.exe

hello.exe: main.o factorial.o hello.o

g++ main.o factorial.o hello.o -o hello.exe