cmake 找不到用 vcpkg 安装的库

Question

我想vcpkg在 Windows 的 CMake 项目中使用，因为我需要boost并且xerces都由这个包管理器处理。

我有以下几点CMakeLists.txt：

cmake_minimum_required (VERSION 3.12.0)

project (myproj)

set (CMAKE_PREFIX_PATH ${XERCES_ROOT})
set (Boost_USE_STATIC_LIBS ON)
set (Boost_USE_MULTITHREADED ON)
unset (Boost_INCLUDE_DIR CACHE)
unset (Boost_LIBRARY_DIRS CACHE)

# set (CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/../../cmake/modules)
find_package (Boost COMPONENTS filesystem regex REQUIRED)
find_package (XercesC CONFIG REQUIRED)

set (CMAKE_INCLUDE_CURRENT_DIR ON)
message (STATUS "binary dir is ${CMAKE_BINARY_DIR}")
include_directories (${CMAKE_BINARY_DIR}/${PROJECT_NAME}/)
include_directories (${CMAKE_CURRENT_SOURCE_DIR}/..)
include_directories (${Boost_INCLUDE_DIRS})
include_directories (${XercesC_INCLUDE_DIRS})

set (PROJECT_SRC
  code.cpp
  )

add_library (${PROJECT_NAME} SHARED ${PROJECT_SRC})
add_dependencies (${PROJECT_NAME} UPDATE_RESOURCES)
target_link_libraries (${PROJECT_NAME} ${Boost_LIBRARIES} XercesC::XercesC)

Boost并xerces-c安装了vcpkg. 由于我使用的是 Visual Studio Code，因此我在以下位置设置vcpkg变量settings.json：

  "cmake.configureSettings": {
    "CMAKE_TOOLCHAIN_FILE" : "some/path/vcpkg/scripts/buildsystems/vcpkg.cmake",
    "VCPKG_TARGET_TRIPLET": "x64-windows"
  }

当我运行 che CMake 时，出现以下错误：

[cmake] CMake Error at C:/Program Files/CMake/share/cmake-3.14/Modules/FindBoost.cmake:2132 (message):
[cmake]   Unable to find the requested Boost libraries.
[cmake] 
[cmake]   Unable to find the Boost header files.  Please set BOOST_ROOT to the root
[cmake]   directory containing Boost or BOOST_INCLUDEDIR to the directory containing
[cmake]   Boost's headers.
[cmake] Call Stack (most recent call first):
[cmake]   D:/projects/vcpkg/scripts/buildsystems/vcpkg.cmake:233 (_find_package)
[cmake]   src/myroject/CMakeLists.txt:24 (find_package)
[cmake] 
[cmake] 
[cmake] CMake Error at D:/Projects/vcpkg/installed/x64-windows/share/xercesc/vcpkg-cmake-wrapper.cmake:1 (_find_package):
[cmake]   Could not find a package configuration file provided by "XercesC" with any
[cmake]   of the following names:
[cmake] 
[cmake]     XercesCConfig.cmake
[cmake]     xercesc-config.cmake
[cmake] 
[cmake]   Add the installation prefix of "XercesC" to CMAKE_PREFIX_PATH or set
[cmake]   "XercesC_DIR" to a directory containing one of the above files.  If
[cmake]   "XercesC" provides a separate development package or SDK, be sure it has
[cmake]   been installed.
[cmake] Call Stack (most recent call first):
[cmake]   D:/Projects/vcpkg/scripts/buildsystems/vcpkg.cmake:189 (include)
[cmake]   src/ZLA/CMakeLists.txt:25 (find_package)
[cmake] 
[cmake] 
[cmake] Configuring incomplete, errors occurred!
[cmake] See also "D:/Projects/zla/build/vscode/CMakeFiles/CMakeOutput.log".
[cms-driver] Error during CMake configure: [cmake-server] Configuration failed.

目前我已经xerces用 vcpkg 命令安装了，虽然目前没有安装 boost，但我期待在执行 cmake 命令期间，vcpkg将下载并构建所需的构建包。

我也试过命令行：

 cmake -DCMAKE_TOOLCHAIN_FILE=D:/Projects/vcpkg/scripts/buildsystems/vcpkg.cmake -DVCPKG_TARGET_TRIPLET=x64-windows ../

但结果是一样的。

我做错了什么？如何成功使用 vcpkg？

Answer 1

理论上它很简单（假设 vcpkg 安装在C:/vcpkggithub actions 中）；

1. 安装你的“foo”包vcpkg install foo

2. 确保您的 CMakeLists.txt 找到并使用该包；

   find_package(FOO)
   # Use these instead of the package doesn't have proper cmake 
   package support.
   # find_path(FOO_INCLUDE_DIRS foo.h)
   # find_library(FOO_LIBRARYS foo)
   include_directories(${FOO_INCLUDE_DIRS})
   target_link_libraries(myprogram ${FOO_LIBRARIES})                                     
   

3. 运行 cmake

   find_package(FOO)
   # Use these instead of the package doesn't have proper cmake 
   package support.
   # find_path(FOO_INCLUDE_DIRS foo.h)
   # find_library(FOO_LIBRARYS foo)
   include_directories(${FOO_INCLUDE_DIRS})
   target_link_libraries(myprogram ${FOO_LIBRARIES})                                     
   

--triplet x64-windows但是......在我添加到命令之前，这对我不起作用vcpkg install。

设置DCMAKE_TOOLCHAIN_FILE各种CMAKE_(SYSTEM_)?(PREFIX|LIBRARY|INCLUDE|FRAMEWORK)_PATH变量以使 find_*() cmake 函数能够工作，但请注意这些路径包括 VCPKG_TARGET_TRIPLET。在我的例子中，包安装vcpkg install <foo>默认为x86-windows，但随后调用 cmake-DCMAKE_TOOLCHAIN_FILE=C:/....默认为x64-windows，因此它找不到包。

当前 vcpkg 默认为较旧的 x86 目标，但现代 Visual Studio（由 githup 操作使用）默认为 x64。修复方法是使用vcpkg -triplet x64-windows install <foo>. 我花了很长时间才发现这一点。

Answer 2

1. 您需要事先安装软件包（使用 vcpkg install ）。

（然后您可以将工具链指定为 CMake 选项：

-DCMAKE_TOOLCHAIN_FILE=C:\path\to\vcpkg\scripts\buildsystems\vcpkg.cmake

但是如果您已经指定了一个工具链，这将不起作用，例如在交叉编译时。）

2. 相反，“包括”它以避免这个问题：

在 find_package() 之前将此行添加到项目 CMakeLists.txt 中：

include(/path/to/vcpkg/scripts/buildsystems/vcpkg.cmake)

Answer 3

boost 目前尚未安装，但我预计在执行 cmake 命令期间，vcpkg 将下载并构建所需的构建包。

据我所知，情况并非如此。您需要vcpkg预先为您计划使用的三元组安装所需的软件包（即x64-windows）。然后，您需要确保在运行 CMake 时使用了正确的三元组（检查 中的VCPKG_TARGET_TRIPLET变量CMakeCache.txt）。如果不正确，您可以更改它并使用 CMake 重新配置。

此外，根据您得到的错误输出，xerces使用vcpkg. 您可以vcpkg通过运行来检查安装的内容：

vcpkg list --triplet x64-windows