文档建议反馈控制台
首页
学习
活动
专区
圈层
工具
MCP广场
文章/答案/技术大牛
发布
首页
学习
活动
专区
圈层
工具
MCP广场
返回腾讯云官网
社区首页 >问答首页 >无法在CMake中创建动态库并将其链接到另一个动态库？

问无法在CMake中创建动态库并将其链接到另一个动态库？
EN

Stack Overflow用户
提问于 2019-09-24 17:57:47
回答 1查看 1.4K关注 0票数 0

目前，我正在Windows 10下开发一个使用不同库的小型应用程序。首先，我想说，我已经做了好几年的专业开发人员了，但是我总是在不同的环境(主要是GNU/Linux和MacOS)上开发，对于我来说，它总是更像游戏操作系统而不是工作的操作系统；现在Windows 10似乎更加开放源码友好，我想试一试，看看结合WSL-2和vcpkg，我能不能有一些有用的东西。所以我觉得用快板库开发一个简单的跨平台的2D应用程序可能是个好主意。

我使用VisualStudio2019CommunityEdition创建了一个新的CMake项目，并在项目本身内设置了一个vcpkg克隆(我不觉得这是个好主意，但我有点喜欢把所有东西都放在一个地方)。使用vcpkg，我安装了我想要使用的两个库:快板和sqlite3。这两种安装都进行得很好，我实际上对vcpkg本身感到非常惊讶。

我设置了我的项目结构:由于这将是一个模块化的项目，我开始通过CMake函数在add_library(lib_name SHARED sources)中创建一堆共享库，最后我得到了一个类似于以下结构的结构：

代码语言：javascript
运行
复制
project_root/CMakeLists.txt
project_root/src/main.cpp

project_root/core
project_root/core/CMakeLists.txt
project_root/core/include/core/bunch_of_headers.hpp
project_root/core/src/bunch_of_sources.cpp

project_root/model
project_root/model/CMakeLists.txt
project_root/model/include/model/bunch_of_headers.hpp
project_root/model/src/bunch_of_sources.cpp

以此类推。

project_root中的每个文件夹都包含一个模块，所有CMakeLists文件看起来都是如下所示：

代码语言：javascript
运行
复制
add_library(model SHARED all_the_source_files.cpp)

include(DeclareNewSharedLibrary)
declare_new_shared_library(model)

find_package(sqlite3 CONFIG REQUIRED)
target_link_libraries(model sqlite3)

其中，declare_new_shared_library()在单独的cmake模块中定义为以下函数

代码语言：javascript
运行
复制
function(declare_new_shared_library lib_name)
    message(STATUS "Declaring new library ${lib_name}")
    include(GenerateExportHeader)
    generate_export_header(${lib_name})

    target_include_directories(${lib_name}
        PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/include"
        PUBLIC "${CMAKE_CURRENT_BINARY_DIR}"
    )

    set_target_properties(${lib_name} PROPERTIES
        IMPORTED_IMPLIB "${CMAKE_CURRENT_BINARY_DIR}/${lib_name}.lib"
        IMPORTED_LOCATION "${CMAKE_CURRENT_BINARY_DIR}/${lib_name}.dll"
    )
endfunction(declare_new_shared_library)

到目前为止还没什么好想的。

现在，每个模块都编译得很好，即使当我将共享库链接到通过vcpkg下载的库时也是如此(如上面的示例所示)。Windows上的ld正确地输出所需的文件(.lib和.dll)，并按预期将它们复制到${CMAKE_RUNTIME_OUTPUT_DIRECTORY}中。

我在这里遇到的问题是，有一个one库不编译。CMake文件与其他文件完全相同，只是我链接到了快板库(与其他文件一样，它是通过vcpkg安装的)。下面是用于比较的CMake文件：

代码语言：javascript
运行
复制
add_library(core SHARED all_the_sources.cpp)

include(DeclareNewSharedLibrary)
declare_new_shared_library(core)

find_package(allegro CONFIG REQUIRED)
target_link_libraries(core allegro)

当我试图编译这个目标(无论是直接编译还是通过依赖关系系统编译)时，我会得到以下错误

TL;DR：

代码语言：javascript
运行
复制
C:\Dev\ConsultantLife\msvcrtd.lib(exe_main.obj) : error LNK2019: unresolved external symbol main referenced in function "int __cdecl invoke_main(void)" (?invoke_main@@YAHXZ)
C:\Dev\ConsultantLife\bin\core.dll : fatal error LNK1120: 1 unresolved externals

下面是勇士们的长篇版本：

代码语言：javascript
运行
复制
  Cleaning... 3 files.
  [1/2] C:\PROGRA~2\MICROS~1\2019\COMMUN~1\VC\Tools\Llvm\80D306~1.0\bin\clang-cl.exe  /nologo -TP -Dcore_EXPORTS -I..\..\..\core\include -Icore -I..\..\..\vcpkg\installed\x64-windows\include -m64 -fdiagnostics-absolute-paths  /DWIN32 /D_WINDOWS /W3 /GR /EHsc /MDd /Zi /Ob0 /Od /RTC1 /showIncludes /Focore\CMakeFiles\core.dir\Game.cpp.obj /Fdcore\CMakeFiles\core.dir\ -c ..\..\..\core\Game.cpp
  [2/2] cmd.exe /C "cd . && "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Common7\IDE\CommonExtensions\Microsoft\CMake\CMake\bin\cmake.exe" -E vs_link_dll --intdir=core\CMakeFiles\core.dir --rc=C:\PROGRA~2\WI3CF2~1\10\bin\100183~1.0\x64\rc.exe --mt=C:\PROGRA~2\WI3CF2~1\10\bin\100183~1.0\x64\mt.exe --manifests  -- C:\PROGRA~2\MICROS~1\2019\COMMUN~1\VC\Tools\MSVC\1422~1.279\bin\Hostx64\x64\link.exe /nologo core\CMakeFiles\core.dir\Game.cpp.obj  /out:bin\core.dll /implib:core\core.lib /pdb:bin\core.pdb /dll /version:0.0 /machine:x64 /debug /INCREMENTAL  ..\..\..\vcpkg\installed\x64-windows\debug\lib\allegro-debug.lib kernel32.lib user32.lib gdi32.lib winspool.lib shell32.lib ole32.lib oleaut32.lib uuid.lib comdlg32.lib advapi32.lib  && cmd.exe /C "cd /D C:\Dev\ConsultantLife\out\build\x64-Debug\core && powershell -noprofile -executionpolicy Bypass -file C:/Dev/ConsultantLife/vcpkg/scripts/buildsystems/msbuild/applocal.ps1 -targetBinary C:/Dev/ConsultantLife/out/build/x64-Debug/bin/core.dll -installedDir C:/Dev/ConsultantLife/vcpkg/installed/x64-windows/debug/bin -OutVariable out""
  FAILED: bin/core.dll core/core.lib 
  cmd.exe /C "cd . && "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Common7\IDE\CommonExtensions\Microsoft\CMake\CMake\bin\cmake.exe" -E vs_link_dll --intdir=core\CMakeFiles\core.dir --rc=C:\PROGRA~2\WI3CF2~1\10\bin\100183~1.0\x64\rc.exe --mt=C:\PROGRA~2\WI3CF2~1\10\bin\100183~1.0\x64\mt.exe --manifests  -- C:\PROGRA~2\MICROS~1\2019\COMMUN~1\VC\Tools\MSVC\1422~1.279\bin\Hostx64\x64\link.exe /nologo core\CMakeFiles\core.dir\Game.cpp.obj  /out:bin\core.dll /implib:core\core.lib /pdb:bin\core.pdb /dll /version:0.0 /machine:x64 /debug /INCREMENTAL  ..\..\..\vcpkg\installed\x64-windows\debug\lib\allegro-debug.lib kernel32.lib user32.lib gdi32.lib winspool.lib shell32.lib ole32.lib oleaut32.lib uuid.lib comdlg32.lib advapi32.lib  && cmd.exe /C "cd /D C:\Dev\ConsultantLife\out\build\x64-Debug\core && powershell -noprofile -executionpolicy Bypass -file C:/Dev/ConsultantLife/vcpkg/scripts/buildsystems/msbuild/applocal.ps1 -targetBinary C:/Dev/ConsultantLife/out/build/x64-Debug/bin/core.dll -installedDir C:/Dev/ConsultantLife/vcpkg/installed/x64-windows/debug/bin -OutVariable out""
  LINK Pass 1: command "C:\PROGRA~2\MICROS~1\2019\COMMUN~1\VC\Tools\MSVC\1422~1.279\bin\Hostx64\x64\link.exe /nologo core\CMakeFiles\core.dir\Game.cpp.obj /out:bin\core.dll /implib:core\core.lib /pdb:bin\core.pdb /dll /version:0.0 /machine:x64 /debug /INCREMENTAL ..\..\..\vcpkg\installed\x64-windows\debug\lib\allegro-debug.lib kernel32.lib user32.lib gdi32.lib winspool.lib shell32.lib ole32.lib oleaut32.lib uuid.lib comdlg32.lib advapi32.lib /MANIFEST /MANIFESTFILE:core\CMakeFiles\core.dir/intermediate.manifest core\CMakeFiles\core.dir/manifest.res" failed (exit code 1120) with the following output:
     Creating library core\core.lib and object core\core.exp
C:\Dev\ConsultantLife\msvcrtd.lib(exe_main.obj) : error LNK2019: unresolved external symbol main referenced in function "int __cdecl invoke_main(void)" (?invoke_main@@YAHXZ)
C:\Dev\ConsultantLife\bin\core.dll : fatal error LNK1120: 1 unresolved externals
  ninja: build stopped: subcommand failed.

现在，据我所知，链接器正在尝试将我的库链接为可执行文件，因为它无法找到main函数(是的，这是一个库，亲爱的.)它抱怨并给出一个错误。

项目中其他库的编译具有完全相同的link.exe命令(除了系统库之外的不同库)，而且不会失败。

现在我想问一问:我是否做错了什么，allegro-5.2中是否有bug (尽管我不知道库如何查找主方法，链接器如何查找)。好吧，你明白我的意思了)还是我应该放弃一切？

这会是Allegro.cmake文件的问题吗？我不得不承认，我从未在专业项目中使用过CMake (我们是一群仍在使用GNU &Co.)的老家伙。所以我可能漏掉了什么。下面是我创建的文件(从vcpkg文件夹中找到的其他cmake文件复制/粘贴)

代码语言：javascript
运行
复制
### Allegro-config.cmake
include(${CMAKE_CURRENT_LIST_DIR}/Allegro-targets.cmake)


### Allegro-targets.cmake
# Generated by CMake

if("${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION}" LESS 2.5)
   message(FATAL_ERROR "CMake >= 2.6.0 required")
endif()
cmake_policy(PUSH)
cmake_policy(VERSION 2.6)
#----------------------------------------------------------------
# Generated CMake target import file.
#----------------------------------------------------------------

# Commands may need to know the format version.
set(CMAKE_IMPORT_FILE_VERSION 1)

# Protect against multiple inclusion, which would fail when already imported targets are added once more.
set(_targetsDefined)
set(_targetsNotDefined)
set(_expectedTargets)
foreach(_expectedTarget sqlite3)
  list(APPEND _expectedTargets ${_expectedTarget})
  if(NOT TARGET ${_expectedTarget})
    list(APPEND _targetsNotDefined ${_expectedTarget})
  endif()
  if(TARGET ${_expectedTarget})
    list(APPEND _targetsDefined ${_expectedTarget})
  endif()
endforeach()
if("${_targetsDefined}" STREQUAL "${_expectedTargets}")
  unset(_targetsDefined)
  unset(_targetsNotDefined)
  unset(_expectedTargets)
  set(CMAKE_IMPORT_FILE_VERSION)
  cmake_policy(POP)
  return()
endif()
if(NOT "${_targetsDefined}" STREQUAL "")
  message(FATAL_ERROR "Some (but not all) targets in this export set were already defined.\nTargets Defined: ${_targetsDefined}\nTargets not yet defined: ${_targetsNotDefined}\n")
endif()
unset(_targetsDefined)
unset(_targetsNotDefined)
unset(_expectedTargets)


# Compute the installation prefix relative to this file.
set(_IMPORT_PREFIX "${PROJECT_SOURCE_DIR}/vcpkg/installed/${VCPKG_TARGET_TRIPLET}")

# Create imported target allegro
add_library(allegro SHARED IMPORTED)

set_target_properties(allegro PROPERTIES
  INTERFACE_INCLUDE_DIRECTORIES "${_IMPORT_PREFIX}/include"
)

# Load information for each installed configuration.
file(GLOB CONFIG_FILES "${CMAKE_CURRENT_LIST_DIR}/Allegro-targets-*.cmake")
foreach(f ${CONFIG_FILES})
  include(${f})
endforeach()

# Cleanup temporary variables.
set(_IMPORT_PREFIX)

# Loop over all imported files and verify that they actually exist
foreach(target ${_IMPORT_CHECK_TARGETS} )
  foreach(file ${_IMPORT_CHECK_FILES_FOR_${target}} )
    if(NOT EXISTS "${file}" )
      message(FATAL_ERROR "The imported target \"${target}\" references the file
   \"${file}\"
but this file does not exist.  Possible reasons include:
* The file was deleted, renamed, or moved to another location.
* An install or uninstall procedure did not complete successfully.
* The installation package was faulty and contained
   \"${CMAKE_CURRENT_LIST_FILE}\"
but not all the files it references.
")
    endif()
  endforeach()
  unset(_IMPORT_CHECK_FILES_FOR_${target})
endforeach()
unset(_IMPORT_CHECK_TARGETS)

# This file does not depend on other imported targets which have
# been exported from the same project but in a separate export set.

# Commands beyond this point should not need to know the version.
set(CMAKE_IMPORT_FILE_VERSION)
cmake_policy(POP)



### Allegro-targets-debug.cmake
#----------------------------------------------------------------
# Generated CMake target import file for configuration "Debug".
#----------------------------------------------------------------

# Commands may need to know the format version.
set(CMAKE_IMPORT_FILE_VERSION 1)

# Import target "allegro" for configuration "Debug"
set_property(TARGET allegro APPEND PROPERTY IMPORTED_CONFIGURATIONS DEBUG)
set_target_properties(allegro PROPERTIES
    IMPORTED_IMPLIB_DEBUG "${_IMPORT_PREFIX}/debug/lib/allegro-debug.lib"
    IMPORTED_LOCATION_DEBUG "${_IMPORT_PREFIX}/debug/bin/allegro-debug-5.2.dll"
  )

list(APPEND _IMPORT_CHECK_TARGETS allegro )
list(APPEND _IMPORT_CHECK_FILES_FOR_allegro 
    "${_IMPORT_PREFIX}/debug/lib/allegro-debug.lib" 
    "${_IMPORT_PREFIX}/debug/bin/allegro-debug-5.2.dll"
)

# Commands beyond this point should not need to know the version.
set(CMAKE_IMPORT_FILE_VERSION)

由于这种行为在过去几天里一直让我抓狂，我在Linux环境中测试了相同的配置(vcpkg，cmake，.)它就像一种魅力，我把所有的东西都整理好了，它起了作用。我看到的唯一不同是，Linux上的vcpkg只使用静态库，而在Windows上使用dll。

对不起，文字墙！

谢谢你的帮助!

windows
dll
cmake
c++
EN

回答 1

Stack Overflow用户

回答已采纳

发布于 2019-09-24 19:13:46

通常情况下，我在寻求帮助几分钟后就能自己找到答案。

看起来，快板试图找到一个主要的方法，这就是为什么连接失败。

解决方案是将以下行添加到Allegro-config.cmake文件中

代码语言：javascript
运行
复制
target_compile_definitions(allegro INTERFACE ALLEGRO_NO_MAGIC_MAIN)
票数 0
EN
页面原文内容由Stack Overflow提供。腾讯云小微IT领域专用引擎提供翻译支持
原文链接：

https://stackoverflow.com/questions/58085848

复制
相关文章

相似问题

领券

腾讯云开发者

扫码关注腾讯云开发者

扫码关注腾讯云开发者

领取腾讯云代金券

热门产品

热门推荐

更多推荐

Copyright © 2013 - 2025 Tencent Cloud. All Rights Reserved. 腾讯云 版权所有 

深圳市腾讯计算机系统有限公司 ICP备案/许可证号：粤B2-20090059 深公网安备号 44030502008569

腾讯云计算（北京）有限责任公司 京ICP证150476号 |  京ICP备11018762号 | 京公网安备号11010802020287

问题归档专栏文章快讯文章归档关键词归档开发者手册归档开发者手册 Section 归档