使无法链接它刚刚编译的内容

Question

我在一个相当小的爱好项目中，我们正在创建一个游戏，或者至少正在尝试这样做......我们面临的主要问题是我们能够在 MacOS 和 Linux 上编译该项目，但不是在 Windows 上。

我们使用 GLFW 作为 OpenGL 的接口，因此我们需要在屏幕上显示任何内容。问题是当我们告诉 Make 做它的事情时，它会编译每个单独的模块，但由于未定义的引用而无法链接它们。虽然这可能是有道理的，但奇怪的是这些未知的引用都有前缀__imp_，它在源代码中不存在。示例：我们使用了方法glfwInit，但是在尝试制作项目时，我们得到：graphicsengine/libgraphicsengine.a(graphics.cpp.obj):graphics.cpp:(.text+0xa): undefined reference to `_imp__glfwInit'

做了一些研究，我找到了This SO Question，我尝试了其中的答案。它失败了，因为编译后唯一的lib是libglfw3.a，没有任何dll或dll提示。相应地重命名这个文件没有帮助，放置预编译的二进制文件也没有帮助。删除这个文件会导致它重新编译并重新出现，所以清楚地知道它在哪里。

我们还尝试切换到 clang，因为它可能有一个更智能的链接器，但它一开始就不想编译任何东西。

我对此进行了大量研究，发现了无数 SO 答案和论坛帖子中存在类似甚至相同问题的人，每个人都有不同的解决方案，但没有一个对我们有用。

为了生成 Makefile，我们在主子目录中使用 CMake 和以下脚本（别担心，它是从上面调用的，到目前为止我们已经完成了）：

set(GLFW_BUILD_DOCS OFF CACHE BOOL "" FORCE)
set(GLFW_BUILD_TESTS OFF CACHE BOOL "" FORCE)
set(GLFW_BUILD_EXAMPLES OFF CACHE BOOL "" FORCE)
set(GLFW_INSTALL OFF CACHE BOOL "" FORCE)

add_subdirectory(graphicsengine)
add_subdirectory(fileSys)
add_subdirectory(networking)
add_subdirectory(game)

add_subdirectory(glfw-3.2.1)
include_directories(glfw-3.2.1/include)

if (UNIX AND NOT APPLE)  
   find_package(OpenGL REQUIRED)
   include_directories(${OPENGL_INCLUDE_DIR})
endif()

add_executable(${PROJECT_NAME} "${CMAKE_CURRENT_SOURCE_DIR}/main.cpp")

 target_link_libraries(${PROJECT_NAME} graphicsengine fileSys networking game)

if (APPLE)
   target_link_libraries(${PROJECT_NAME} "-framework OpenGL")
endif()
if (WIN32)
   target_link_libraries(${PROJECT_NAME} opengl32 gdi32)
endif()
if (UNIX AND NOT APPLE)  
   target_link_libraries(${PROJECT_NAME} ${OPENGL_gl_LIBRARY})
endif()

target_link_libraries(${PROJECT_NAME} glfw)

install(TARGETS ${PROJECT_NAME} DESTINATION ${INSTALL_DIR})

其余重要的 cmake 调用都在父目录中

这是自定义构建脚本调用的 cmake/make 的完整日志：

debug
release
-- The CXX compiler identification is GNU 5.3.0
-- Check for working CXX compiler: D:/MinGW/bin/g++.exe
-- Check for working CXX compiler: D:/MinGW/bin/g++.exe -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- The C compiler identification is GNU 5.3.0
-- Check for working C compiler: D:/MinGW/bin/gcc.exe
-- Check for working C compiler: D:/MinGW/bin/gcc.exe -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Looking for pthread.h
-- Looking for pthread.h - found
-- Looking for pthread_create
-- Looking for pthread_create - not found
-- Looking for pthread_create in pthreads
-- Looking for pthread_create in pthreads - not found
-- Looking for pthread_create in pthread
-- Looking for pthread_create in pthread - found
-- Found Threads: TRUE
-- Could NOT find Vulkan (missing:  VULKAN_INCLUDE_DIR)
-- Looking for dinput.h
-- Looking for dinput.h - not found
-- Looking for xinput.h
-- Looking for xinput.h - not found
-- Performing Test _GLFW_HAS_DEP
-- Performing Test _GLFW_HAS_DEP - Success
-- Performing Test _GLFW_HAS_ASLR
-- Performing Test _GLFW_HAS_ASLR - Success
-- Performing Test _GLFW_HAS_64ASLR
-- Performing Test _GLFW_HAS_64ASLR - Failed
-- Using Win32 for window creation
-- Configuring done
-- Generating done
-- Build files have been written to: D:/cpp-neon/Workspace/Supermerged
--------------MAKE STARTS HERE--------------
[ 60%] Built target glfw
[ 68%] Built target graphicsengine
[ 76%] Built target fileSys
[ 84%] Built target networking
[ 92%] Built target game
[ 96%] Linking CXX executable Submerged_PR0.exe
graphicsengine/libgraphicsengine.a(graphics.cpp.obj):graphics.cpp:(.text+0xa): undefined reference to `_imp__glfwInit'
graphicsengine/libgraphicsengine.a(graphics.cpp.obj):graphics.cpp:(.text+0x45): undefined reference to `_imp__glfwCreateWindow'
graphicsengine/libgraphicsengine.a(graphics.cpp.obj):graphics.cpp:(.text+0x55): undefined reference to `_imp__glfwTerminate'
graphicsengine/libgraphicsengine.a(graphics.cpp.obj):graphics.cpp:(.text+0x64): undefined reference to `_imp__glfwMakeContextCurrent'
graphicsengine/libgraphicsengine.a(graphics.cpp.obj):graphics.cpp:(.text+0x71): undefined reference to `_imp__glfwWindowShouldClose'
graphicsengine/libgraphicsengine.a(graphics.cpp.obj):graphics.cpp:(.text+0x98): undefined reference to `_imp__glfwSwapBuffers'
graphicsengine/libgraphicsengine.a(graphics.cpp.obj):graphics.cpp:(.text+0x9f): undefined reference to `_imp__glfwPollEvents'
graphicsengine/libgraphicsengine.a(graphics.cpp.obj):graphics.cpp:(.text+0xa8): undefined reference to `_imp__glfwTerminate'
collect2.exe: error: ld returned 1 exit status
source\CMakeFiles\Submerged_PR0.dir\build.make:101: recipe for target 'source/Submerged_PR0.exe' failed
mingw32-make[2]: *** [source/Submerged_PR0.exe] Error 1
CMakeFiles\Makefile2:102: recipe for target 'source/CMakeFiles/Submerged_PR0.dir/all' failed
mingw32-make[1]: *** [source/CMakeFiles/Submerged_PR0.dir/all] Error 2
Makefile:128: recipe for target 'all' failed
mingw32-make: *** [all] Error 2
Make Failed, Aborting Install
PS D:\cpp-neon\Workspace\Supermerged>

如果你想知道，这是我们的项目结构：

上面的 CMakeLists.txt 就是你在 /source 中看到的那个

其余模块的构建方式相同，除了 glfw，您可以在他们的网站上找到它

在这个时间点上，我们或多或少地无助和厌倦了寻找解决方案，我们只是尝试一些东西直到它有点工作，但最终导致一切本不应该存在的巨大混乱，我们都知道结果如何... （咳）这些分支中的哪一个是我做的事情让它做另一件事的地方？（咳嗽）我们希望你们中的一些人（所以) 可能比我们任何人都有更好的方法来找到解决方案。随意提出任何其他可能有助于您找到有效方法的问题！

提前致谢！

以：sDev的名义

Answer 1

我们找到了！

问题其实出在我们的graphics.hpp:

我们拨打了#define GLFW_DLL

这是错误的，因为它必须是

#define GLFW_STATIC

现在它可以工作了