我目前正在尝试在Windows上使用CMake来构建一个包含2个库GLEW和SDL2的C ++项目,但是这样做后,我得到了一个未定义的参考错误,看起来像是:-
PS D:\Projects\C++Projects\game_engine\build>> cmg ..
-- The C compiler identification is GNU 7.1.0
-- The CXX compiler identification is GNU 7.1.0
-- Check for working C compiler: C:/Program Files/MinGW-w64/mingw64/bin/gcc.exe
-- Check for working C compiler: C:/Program Files/MinGW-w64/mingw64/bin/gcc.exe -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: C:/Program Files/MinGW-w64/mingw64/bin/g++.exe
-- Check for working CXX compiler: C:/Program Files/MinGW-w64/mingw64/bin/g++.exe -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: D:/Projects/C++Projects/game_engine/build
Scanning dependencies of target game_engine
[ 25%] Building CXX object CMakeFiles/game_engine.dir/src/MainGame.cpp.obj
[ 50%] Building CXX object CMakeFiles/game_engine.dir/src/Sprite.cpp.obj
[ 75%] Building CXX object CMakeFiles/game_engine.dir/src/main.cpp.obj
[100%] Linking CXX executable game_engine.exe
CMakeFiles\game_engine.dir/objects.a(MainGame.cpp.obj):MainGame.cpp:(.text+0x4b): undefined reference to `SDL_Quit'
CMakeFiles\game_engine.dir/objects.a(MainGame.cpp.obj):MainGame.cpp:(.text+0x141): undefined reference to `SDL_Init'
CMakeFiles\game_engine.dir/objects.a(MainGame.cpp.obj):MainGame.cpp:(.text+0x175): undefined reference to `SDL_CreateWindow'
CMakeFiles\game_engine.dir/objects.a(MainGame.cpp.obj):MainGame.cpp:(.text+0x1e4): undefined reference to `SDL_GL_CreateContext'
CMakeFiles\game_engine.dir/objects.a(MainGame.cpp.obj):MainGame.cpp:(.text+0x240): undefined reference to `__imp_glewInit'
CMakeFiles\game_engine.dir/objects.a(MainGame.cpp.obj):MainGame.cpp:(.text+0x2a4): undefined reference to `SDL_GL_SetAttribute'
CMakeFiles\game_engine.dir/objects.a(MainGame.cpp.obj):MainGame.cpp:(.text+0x2c1): undefined reference to `glClearColor'
CMakeFiles\game_engine.dir/objects.a(MainGame.cpp.obj):MainGame.cpp:(.text+0x39e): undefined reference to `SDL_PollEvent'
CMakeFiles\game_engine.dir/objects.a(MainGame.cpp.obj):MainGame.cpp:(.text+0x438): undefined reference to `glClearDepth'
CMakeFiles\game_engine.dir/objects.a(MainGame.cpp.obj):MainGame.cpp:(.text+0x442): undefined reference to `glClear'
CMakeFiles\game_engine.dir/objects.a(MainGame.cpp.obj):MainGame.cpp:(.text+0x461): undefined reference to `SDL_GL_SwapWindow'
CMakeFiles\game_engine.dir/objects.a(Sprite.cpp.obj):Sprite.cpp:(.text+0x30): undefined reference to `__imp___glewDeleteBuffers'
CMakeFiles\game_engine.dir/objects.a(Sprite.cpp.obj):Sprite.cpp:(.text+0xae): undefined reference to `__imp___glewGenBuffers'
CMakeFiles\game_engine.dir/objects.a(Sprite.cpp.obj):Sprite.cpp:(.text+0x15d): undefined reference to `__imp___glewBindBuffer'
CMakeFiles\game_engine.dir/objects.a(Sprite.cpp.obj):Sprite.cpp:(.text+0x175): undefined reference to `__imp___glewBufferData'
CMakeFiles\game_engine.dir/objects.a(Sprite.cpp.obj):Sprite.cpp:(.text+0x198): undefined reference to `__imp___glewBindBuffer'
CMakeFiles\game_engine.dir/objects.a(Sprite.cpp.obj):Sprite.cpp:(.text+0x1c1): undefined reference to `__imp___glewBindBuffer'
CMakeFiles\game_engine.dir/objects.a(Sprite.cpp.obj):Sprite.cpp:(.text+0x1d9): undefined reference to `__imp___glewEnableVertexAttribArray' CMakeFiles\game_engine.dir/objects.a(Sprite.cpp.obj):Sprite.cpp:(.text+0x1ea): undefined reference to `__imp___glewVertexAttribPointer'
CMakeFiles\game_engine.dir/objects.a(Sprite.cpp.obj):Sprite.cpp:(.text+0x22b): undefined reference to `glDrawArrays'
CMakeFiles\game_engine.dir/objects.a(Sprite.cpp.obj):Sprite.cpp:(.text+0x232): undefined reference to `__imp___glewDisableVertexAttribArray'
CMakeFiles\game_engine.dir/objects.a(Sprite.cpp.obj):Sprite.cpp:(.text+0x243): undefined reference to `__imp___glewBindBuffer'
C:/PROGRA~1/MINGW-~1/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.1.0/../../../../x86_64-w64-mingw32/lib/../lib/libmingw32.a(lib64_libmingw32_a-crt0_c.o):crt0_c.c:(.text.startup+0x2e): undefined reference to `WinMain'
collect2.exe: error: ld returned 1 exit status
make[2]: *** [CMakeFiles\game_engine.dir\build.make:118: game_engine.exe] Error 1
make[1]: *** [CMakeFiles\Makefile2:67: CMakeFiles/game_engine.dir/all] Error 2
make: *** [Makefile:83: all] Error 2
项目树为:-
Root
|-build
|-include
|-GL
|-SDL2
|-MainGame.h
\-Sprite.h
|-lib
|-glew32.lib
|-glew32s.lib
|-SDL2.lib
|-SDL2main.lib
\-SDL2test.lib
\-src
|-main.cpp
|-MainGame.cpp
\-Sprite.cpp
我的CMakeLists.txt文件如下:-
cmake_minimum_required(VERSION 3.11.4)
project (game_engine)
# Bring header files into scope
include_directories(include)
include_directories(include/SDL2)
include_directories(include/GL)
# Retrieve all source files
file(GLOB SOURCES "src/*.cpp")
add_executable(game_engine ${SOURCES})
target_link_libraries(game_engine -L./lib)
目前,我认为未定义的引用是编译器未在SDL和GLEW库中找到对应的.cpp文件的结果。
这使我相信CMakeLists.txt文件的最后一行无法成功链接两个库的.lib文件。
任何帮助都将不胜感激,如果以上错误是由于项目结构不佳而引起的,我怀疑这是这里的主要问题,我将很乐意对其进行更改。
谢谢。
编辑(1):
我希望添加一些我刚刚注意到的东西,即cmake实际上会生成一个makefile,但是之后立即运行make会产生未定义的引用错误。检查makefile,我发现根本没有链接库,这再次确认target_link_libraries()无法链接SDL和GLEW。
这是更新的CMakeLists.txt文件:
cmake_minimum_required(VERSION 3.11.4)
# Project Name
project (game_engine)
# Retrieve all source files
set(SOURCES
${CMAKE_SOURCE_DIR}/src/main.cpp
${CMAKE_SOURCE_DIR}/src/MainGame.cpp
${CMAKE_SOURCE_DIR}/src/Sprite.cpp)
add_executable(game_engine ${SOURCES})
target_include_directories(game_engine PUBLIC
include
include/SDL2
include/GL)
target_link_libraries(game_engine
${CMAKE_SOURCE_DIR}/lib/glew32.lib
${CMAKE_SOURCE_DIR}/lib/glew32s.lib
${CMAKE_SOURCE_DIR}/lib/SDL2.lib
${CMAKE_SOURCE_DIR}/lib/SDL2main.lib
${CMAKE_SOURCE_DIR}/lib/SDL2test.lib)
以及生成的makefile:
# CMAKE generated file: DO NOT EDIT!
# Generated by "MinGW Makefiles" Generator, CMake Version 3.11
# Default target executed when no arguments are given to make.
default_target: all
.PHONY : default_target
# Allow only one "make -f Makefile2" at a time, but pass parallelism.
.NOTPARALLEL:
#=============================================================================
# Special targets provided by cmake.
# Disable implicit rules so canonical targets will work.
.SUFFIXES:
# Remove some rules from gmake that .SUFFIXES does not remove.
SUFFIXES =
.SUFFIXES: .hpux_make_needs_suffix_list
# Suppress display of executed commands.
$(VERBOSE).SILENT:
# A target that is always out of date.
cmake_force:
.PHONY : cmake_force
#=============================================================================
# Set environment variables for the build.
SHELL = cmd.exe
# The CMake executable.
CMAKE_COMMAND = D:\CMake\bin\cmake.exe
# The command to remove a file.
RM = D:\CMake\bin\cmake.exe -E remove -f
# Escaping for special characters.
EQUALS = =
# The top-level source directory on which CMake was run.
CMAKE_SOURCE_DIR = D:\Projects\C++Projects\game_engine
# The top-level build directory on which CMake was run.
CMAKE_BINARY_DIR = D:\Projects\C++Projects\game_engine\build
#=============================================================================
# Targets provided globally by CMake.
# Special rule for the target edit_cache
edit_cache:
@$(CMAKE_COMMAND) -E cmake_echo_color --switch=$(COLOR) --cyan "Running CMake cache editor..."
D:\CMake\bin\cmake-gui.exe -H$(CMAKE_SOURCE_DIR) -B$(CMAKE_BINARY_DIR)
.PHONY : edit_cache
# Special rule for the target edit_cache
edit_cache/fast: edit_cache
.PHONY : edit_cache/fast
# Special rule for the target rebuild_cache
rebuild_cache:
@$(CMAKE_COMMAND) -E cmake_echo_color --switch=$(COLOR) --cyan "Running CMake to regenerate build system..."
D:\CMake\bin\cmake.exe -H$(CMAKE_SOURCE_DIR) -B$(CMAKE_BINARY_DIR)
.PHONY : rebuild_cache
# Special rule for the target rebuild_cache
rebuild_cache/fast: rebuild_cache
.PHONY : rebuild_cache/fast
# The main all target
all: cmake_check_build_system
$(CMAKE_COMMAND) -E cmake_progress_start D:\Projects\C++Projects\game_engine\build\CMakeFiles D:\Projects\C++Projects\game_engine\build\CMakeFiles\progress.marks
$(MAKE) -f CMakeFiles\Makefile2 all
$(CMAKE_COMMAND) -E cmake_progress_start D:\Projects\C++Projects\game_engine\build\CMakeFiles 0
.PHONY : all
# The main clean target
clean:
$(MAKE) -f CMakeFiles\Makefile2 clean
.PHONY : clean
# The main clean target
clean/fast: clean
.PHONY : clean/fast
# Prepare targets for installation.
preinstall: all
$(MAKE) -f CMakeFiles\Makefile2 preinstall
.PHONY : preinstall
# Prepare targets for installation.
preinstall/fast:
$(MAKE) -f CMakeFiles\Makefile2 preinstall
.PHONY : preinstall/fast
# clear depends
depend:
$(CMAKE_COMMAND) -H$(CMAKE_SOURCE_DIR) -B$(CMAKE_BINARY_DIR) --check-build-system CMakeFiles\Makefile.cmake 1
.PHONY : depend
#=============================================================================
# Target rules for targets named game_engine
# Build rule for target.
game_engine: cmake_check_build_system
$(MAKE) -f CMakeFiles\Makefile2 game_engine
.PHONY : game_engine
# fast build rule for target.
game_engine/fast:
$(MAKE) -f CMakeFiles\game_engine.dir\build.make CMakeFiles/game_engine.dir/build
.PHONY : game_engine/fast
src/MainGame.obj: src/MainGame.cpp.obj
.PHONY : src/MainGame.obj
# target to build an object file
src/MainGame.cpp.obj:
$(MAKE) -f CMakeFiles\game_engine.dir\build.make CMakeFiles/game_engine.dir/src/MainGame.cpp.obj
.PHONY : src/MainGame.cpp.obj
src/MainGame.i: src/MainGame.cpp.i
.PHONY : src/MainGame.i
# target to preprocess a source file
src/MainGame.cpp.i:
$(MAKE) -f CMakeFiles\game_engine.dir\build.make CMakeFiles/game_engine.dir/src/MainGame.cpp.i
.PHONY : src/MainGame.cpp.i
src/MainGame.s: src/MainGame.cpp.s
.PHONY : src/MainGame.s
# target to generate assembly for a file
src/MainGame.cpp.s:
$(MAKE) -f CMakeFiles\game_engine.dir\build.make CMakeFiles/game_engine.dir/src/MainGame.cpp.s
.PHONY : src/MainGame.cpp.s
src/Sprite.obj: src/Sprite.cpp.obj
.PHONY : src/Sprite.obj
# target to build an object file
src/Sprite.cpp.obj:
$(MAKE) -f CMakeFiles\game_engine.dir\build.make CMakeFiles/game_engine.dir/src/Sprite.cpp.obj
.PHONY : src/Sprite.cpp.obj
src/Sprite.i: src/Sprite.cpp.i
.PHONY : src/Sprite.i
# target to preprocess a source file
src/Sprite.cpp.i:
$(MAKE) -f CMakeFiles\game_engine.dir\build.make CMakeFiles/game_engine.dir/src/Sprite.cpp.i
.PHONY : src/Sprite.cpp.i
src/Sprite.s: src/Sprite.cpp.s
.PHONY : src/Sprite.s
# target to generate assembly for a file
src/Sprite.cpp.s:
$(MAKE) -f CMakeFiles\game_engine.dir\build.make CMakeFiles/game_engine.dir/src/Sprite.cpp.s
.PHONY : src/Sprite.cpp.s
src/main.obj: src/main.cpp.obj
.PHONY : src/main.obj
# target to build an object file
src/main.cpp.obj:
$(MAKE) -f CMakeFiles\game_engine.dir\build.make CMakeFiles/game_engine.dir/src/main.cpp.obj
.PHONY : src/main.cpp.obj
src/main.i: src/main.cpp.i
.PHONY : src/main.i
# target to preprocess a source file
src/main.cpp.i:
$(MAKE) -f CMakeFiles\game_engine.dir\build.make CMakeFiles/game_engine.dir/src/main.cpp.i .PHONY : src/main.cpp.i
src/main.s: src/main.cpp.s
.PHONY : src/main.s
# target to generate assembly for a file
src/main.cpp.s:
$(MAKE) -f CMakeFiles\game_engine.dir\build.make CMakeFiles/game_engine.dir/src/main.cpp.s .PHONY : src/main.cpp.s
# Help Target
help:
@echo The following are some of the valid targets for this Makefile:
@echo ... all (the default if no target is provided)
@echo ... clean
@echo ... depend
@echo ... game_engine
@echo ... edit_cache
@echo ... rebuild_cache
@echo ... src/MainGame.obj
@echo ... src/MainGame.i
@echo ... src/MainGame.s
@echo ... src/Sprite.obj
@echo ... src/Sprite.i
@echo ... src/Sprite.s
@echo ... src/main.obj
@echo ... src/main.i
@echo ... src/main.s
.PHONY : help
#=============================================================================
# Special targets to cleanup operation of make.
# Special rule to run CMake to check the build system integrity.
# No rule that depends on this can have commands that come from listfiles
# because they might be regenerated.
cmake_check_build_system:
$(CMAKE_COMMAND) -H$(CMAKE_SOURCE_DIR) -B$(CMAKE_BINARY_DIR) --check-build-system CMakeFiles\Makefile.cmake 0
.PHONY : cmake_check_build_system
编辑(2):已解决
在确定.lib文件未正确链接之后,我决定通过它们的源包重新下载GLEW和SDL2库。它们都带有cmake作为构建选项,因此,我能够访问静态库(.a)+导入库(.dll.a)。
我用这些库替换了lib的内容,并更新了我的CMakeLists.txt文件以包括它们以及OpenGL库:
cmake_minimum_required(VERSION 3.11.4)
# Project Name
project (game_engine)
# Retrieve all source files
set(SOURCES
"${CMAKE_SOURCE_DIR}/src/main.cpp"
"${CMAKE_SOURCE_DIR}/src/MainGame.cpp"
"${CMAKE_SOURCE_DIR}/src/Sprite.cpp")
add_executable(game_engine ${SOURCES})
find_package(OpenGL REQUIRED)
target_include_directories(game_engine PUBLIC
include
include/SDL2
include/GL
${OPENGL_INCLUDE_DIRS})
target_link_libraries(game_engine
"${CMAKE_SOURCE_DIR}/lib/glew32.dll"
"${CMAKE_SOURCE_DIR}/lib/libglew32.a"
"${CMAKE_SOURCE_DIR}/lib/libglew32.dll.a"
"${CMAKE_SOURCE_DIR}/lib/libSDL2.dll"
"${CMAKE_SOURCE_DIR}/lib/libSDL2.dll.a"
"${CMAKE_SOURCE_DIR}/lib/libSDL2main.a"
"${CMAKE_SOURCE_DIR}/lib/libSDL2-static.a"
"${OPENGL_LIBRARIES}")
add_custom_command(TARGET game_engine POST_BUILD
COMMAND ${CMAKE_COMMAND} -E copy_if_different
"${CMAKE_SOURCE_DIR}/lib/glew32.dll"
"${CMAKE_BINARY_DIR}")
add_custom_command(TARGET game_engine POST_BUILD
COMMAND ${CMAKE_COMMAND} -E copy_if_different
"${CMAKE_SOURCE_DIR}/lib/libSDL2.dll"
"${CMAKE_BINARY_DIR}")
这解决了使用未定义引用的主要问题,但是还剩下一个,它是对WinMain的未定义引用。要解决此问题,我在包含“ SDL.h”之前将#define SDL_MAIN_HANDLED
添加到了main.cpp文件中。
答案 0 :(得分:1)
target_link_libraries需要CMake目标或库的路径。
尝试更改
target_link_libraries(game_engine -L./lib)
与
target_link_libraries(game_engine
${CMAKE_SOURCE_DIR}/lib/libglew32.lib
${CMAKE_SOURCE_DIR}/lib/glew32s.lib
${CMAKE_SOURCE_DIR}/lib/SDL2.lib
${CMAKE_SOURCE_DIR}/lib/SDL2main.lib
${CMAKE_SOURCE_DIR}/lib/SDL2test.lib
)
其他建议:
GLOB
。有关合理性,请参见file(GLOB...)文档include_directories
更喜欢使用target_include_directories GLEW_LIBRARIES
之类的变量)会更健壮。答案 1 :(得分:0)
您可以尝试添加
link_directories($ {CMAKE_SOURCE_DIR} / lib)
之前
add_executable(game_engine $ {SOURCES})吗?