makefile: no executable created - c++

Question

I have used openGL with glut before and SDL2 on its own before. Now I try to make an optimized project with Glew, SDL2 and OpenGL. I want it to be able to run on Linux(I mainly use Debian),OSX and Windows. So I tried to write my own makefile. This code should only create a window for me.
Im developing on osx.
I have only my main.cpp, Display.cpp and Display.h
This is what i tried:
#my compiler
CC=g++
#my program name
PRGNAME=booom
#library search directory
LIBDIR=-L/usr/lib -L/usr/local/lib
#library names
#uses libSDL.a, libGLEW.a
LIBNAME=-lSDL -lGLEW
#includes for libraries
INCLUDES=-I/usr/include -I/usr/local/include
#my compiler options
CFLAGS=-c -Wall
all: main.o Display.o
$(CC) $(CFLAGS) $(INCLUDES) $(LIBDIR) $(LIBNAME) -o $(PRGNAME) main.o Display.o
#main.cpp is the dependency of main.o
main.o: main.cpp
$(CC) $(CFLAGS) $(INCLUDES) $(LIBDIR) $(LIBNAME) main.cpp
Display.o: Display.cpp
$(CC) $(CFLAGS) $(INCLUDES) $(LIBDIR) $(LIBNAME) Display.cpp
clean:
rm -rf *o booom
I get a main.o and a Display.o file, but i don't get an executable.
When I do "make clean && make" this is my output:
macbook-mehrschwein:Booom Mehrschwein$ make clean && make
rm -rf *o booom
g++ -c -Wall -I/usr/include -I/usr/local/include -L/usr/lib -L/usr/local/lib -lSDL -lGLEW main.cpp
clang: warning: -lSDL: 'linker' input unused
clang: warning: -lGLEW: 'linker' input unused
clang: warning: argument unused during compilation: '-L/usr/lib'
clang: warning: argument unused during compilation: '-L/usr/local/lib'
g++ -c -Wall -I/usr/include -I/usr/local/include -L/usr/lib -L/usr/local/lib -lSDL -lGLEW Display.cpp
clang: warning: -lSDL: 'linker' input unused
clang: warning: -lGLEW: 'linker' input unused
clang: warning: argument unused during compilation: '-L/usr/lib'
clang: warning: argument unused during compilation: '-L/usr/local/lib'
g++ -c -Wall -I/usr/include -I/usr/local/include -L/usr/lib -L/usr/local/lib -lSDL -lGLEW -o booom main.o Display.o
clang: warning: -lSDL: 'linker' input unused
clang: warning: -lGLEW: 'linker' input unused
clang: warning: main.o: 'linker' input unused
clang: warning: Display.o: 'linker' input unused
clang: warning: argument unused during compilation: '-Wall'
clang: warning: argument unused during compilation: '-I /usr/include'
clang: warning: argument unused during compilation: '-I /usr/local/include'
clang: warning: argument unused during compilation: '-L/usr/lib'
clang: warning: argument unused during compilation: '-L/usr/local/lib'
macbook-mehrschwein:Booom Mehrschwein$

Answer 1

The problem is in -c flag that you use in all stages.
It means to compile an object file but not to link.
Remove it for your all target. Like:
all: main.o Display.o
$(CC) $(LIBDIR) $(LIBNAME) -o $(PRGNAME) main.o Display.o
This fixed the problem with linking.
Now ensure that you have libSDL in the folders you specify.

Answer 2

new version with:
all: main.o Display.o
$(CC) $(LIBDIR) $(LIBNAME) -o $(PRGNAME) main.o Display.o
main.o: main.cpp
$(CC) $(CFLAGS) $(INCLUDES) main.cpp
Display.o: Display.cpp
$(CC) $(CFLAGS) $(INCLUDES) Display.cpp
no warnings for Display.o and main.o anymore.
the error that i get now:
g++ -c -Wall -I/usr/include -I/usr/local/include main.cpp
g++ -c -Wall -I/usr/include -I/usr/local/include Display.cpp
g++ -Wall -I/usr/include -I/usr/local/include -L/usr/lib -L/usr/local/lib -o booom main.o Display.o -lSDL -lGLEW
ld: library not found for -lSDL
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [all] Error 1
EDIT: The name is libSDL2.a, not libSDL.a
but now it tells me that he can't find libGlew.a
libGLEW.a is in /usr/lib
libSDL2.a is in /usr/local/lib
do they both need to be in the same directory?
EDIT2:
Update
I changed a few things, i now build GLEW into "/usr/local", so everything is in the same dir.
my makefile:
#my compiler
CC=g++
#my program name
PRGNAME=booom
#library search directory
LIBDIR=-L/usr/local/lib
#library names
#uses libSDL2.a, libGLEW.a
LIBNAME=-lSDL2 -lGLEW
#includes for libraries
INCLUDES=-I/usr/local/include
#my compiler options
CFLAGS=-c -Wall
all: main.o Display.o
$(CC) $(LIBDIR) $(LIBNAME) -o $(PRGNAME) main.o Display.o
#main.cpp is the dependency of main.o
main.o: main.cpp
$(CC) $(CFLAGS) $(INCLUDES) main.cpp
Display.o: Display.cpp
$(CC) $(CFLAGS) $(INCLUDES) Display.cpp
clean:
rm -rf *o booom
my error now:
rm -rf *o booom
g++ -c -Wall -I/usr/local/include main.cpp
g++ -c -Wall -I/usr/local/include Display.cpp
g++ -L/usr/local/lib -lSDL2 -lGLEW -o booom main.o Display.o
Undefined symbols for architecture x86_64:
"_glClear", referenced from:
Display::Clear(float, float, float, float) in Display.o
"_glClearColor", referenced from:
Display::Clear(float, float, float, float) in Display.o
"_glCullFace", referenced from:
Display::Display(int, int, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in Display.o
"_glEnable", referenced from:
Display::Display(int, int, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) in Display.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [all] Error 1
seams like i got a 32-bit version, while i need a 64-bit version, but i have build that on my own, and don't really know what i have done wrong. normally you also have do do something like ./config before building. but there is no config for GLEW. the only solution that i found on google involves macports, but i would love to do it without macports