之前我曾使用过多的openGL和之前的SDL2。现在我尝试使用Glew，SDL2和OpenGL进行优化项目。我希望它能够在Linux（我主要使用Debian），OSX和Windows上运行。所以我试着编写自己的makefile。这段代码应该只为我创建一个窗口。 我正在开发osx。
我只有main.cpp，Display.cpp和Display.h
这是我试过的：
#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) $(LIBNAME) Display.cpp
clean:
rm -rf *o booom
我得到一个main.o和一个Display.o文件，但我没有得到可执行文件。
当我做“make clean＆amp;＆amp; make”时，这是我的输出：
macbook-mehrschwein:Booom Mehrschwein$ 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$
答案 0 :(得分：0)
问题在于-c标志，您在所有阶段都使用。
它意味着编译目标文件但不链接。
删除all目标。像：
all: main.o Display.o
$(CC) $(LIBDIR) $(LIBNAME) -o $(PRGNAME) main.o Display.o
这解决了链接问题。 现在确保您在指定的文件夹中有libSDL。
答案 1 :(得分：0)
新版本：
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
不再对Display.o和main.o发出警告。
我现在得到的错误：
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
编辑：名称是libSDL2.a，而不是libSDL.a
但现在它告诉我他找不到libGlew.a
libGLEW.a位于/ usr / lib
libSDL2.a位于/ usr / local / lib
他们俩都需要在同一个目录中吗？
EDIT2：
我改变了一些东西，我现在将GLEW构建到＆＃34; / usr / local＆＃34;，所以一切都在同一个目录中。
我的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
我现在的错误：
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