VSCode+CMake环境下如何识别MSYS2安装的Eigen3Config.cmake

在VSCode中配置CMake项目时，添加Eigen3到CMakeLists.txt后重建项目，出现以下错误：

[cmake] CMake Error at CMakeLists.txt:4 (find_package):
[cmake] Could not find a package configuration file provided by "Eigen3" (requested
[cmake] version 3.3) with any of the following names:
[cmake]
[cmake] Eigen3Config.cmake
[cmake] eigen3-config.cmake
[cmake]
[cmake] Add the installation prefix of "Eigen3" to CMAKE_PREFIX_PATH or set
[cmake] "Eigen3_DIR" to a directory containing one of the above files. If "Eigen3"
[cmake] provides a separate development package or SDK, be sure it has been
[cmake] installed.
[cmake]
[cmake] -- Configuring incomplete, errors occurred!

我已尝试：

• 将Eigen3_DIR设置为"/mingw64/share/eigen3/cmake"（该目录下确实存在Eigen3Config.cmake等文件）
• 将CMAKE_PREFIX_PATH设为上述相同路径
• 尝试将路径指向Eigen的include目录
  但问题依旧。

VSCode执行的CMake命令如下：

[main] Building folder: GraphicsEngine 
[proc] Executing command: "C:\Program Files\CMake\bin\cmake.EXE" --version
[proc] Executing command: "C:\Program Files\CMake\bin\cmake.EXE" -E capabilities
[proc] Executing command: C:\msys64\ucrt64\bin\gcc.exe -v
[main] Configuring project: GraphicsEngine 
[proc] Executing command: "C:\Program Files\CMake\bin\cmake.EXE" --no-warn-unused-cli -DCMAKE_BUILD_TYPE:STRING=Debug -DCMAKE_EXPORT_COMPILE_COMMANDS:BOOL=TRUE -DCMAKE_C_COMPILER:FILEPATH=C:\msys64\ucrt64\bin\gcc.exe -DCMAKE_CXX_COMPILER:FILEPATH=C:\msys64\ucrt64\bin\g++.exe -SG:/Documents/Projects/GraphicsEngine -Bg:/Documents/Projects/GraphicsEngine/build -G "MinGW Makefiles"

我的CMakeLists.txt内容：

cmake_minimum_required (VERSION 3.0)
project (graphics_engine)

find_package (Eigen3 3.3 REQUIRED NO_MODULE)
add_executable (example Raytracer.cpp)
target_link_libraries (example Eigen3::Eigen) 

我通过MSYS2安装了mingw-w64-x86_64-eigen3包，请问哪里操作有误或遗漏了什么？

1. 路径匹配问题：你使用的是类Unix格式路径/mingw64/share/eigen3/cmake，但Windows环境下CMake需要Windows格式的绝对路径；同时你当前用的是ucrt64编译器环境，安装的Eigen3实际位于C:/msys64/ucrt64/share/eigen3/cmake，而非mingw64目录，两者环境不匹配导致路径无效。

2. 修正路径配置：

   • 打开文件资源管理器，确认C:\msys64\ucrt64\share\eigen3\cmake目录下存在Eigen3Config.cmake文件
   • 在VSCode的CMake配置中，将Eigen3_DIR设置为这个Windows格式的绝对路径

3. 直接在CMake命令中传递参数：如果插件配置不生效，可直接修改CMake命令，添加路径参数：

"C:\Program Files\CMake\bin\cmake.EXE" --no-warn-unused-cli -DCMAKE_BUILD_TYPE:STRING=Debug -DCMAKE_EXPORT_COMPILE_COMMANDS:BOOL=TRUE -DCMAKE_C_COMPILER:FILEPATH=C:\msys64\ucrt64\bin\gcc.exe -DCMAKE_CXX_COMPILER:FILEPATH=C:\msys64\ucrt64\bin\g++.exe -DEigen3_DIR=C:/msys64/ucrt64/share/eigen3/cmake -SG:/Documents/Projects/GraphicsEngine -Bg:/Documents/Projects/GraphicsEngine/build -G "MinGW Makefiles"

4. 升级最低CMake版本：当前指定的CMake最低版本3.0对现代包配置支持有限，建议修改为3.15+：

cmake_minimum_required (VERSION 3.15)

内容的提问来源于stack exchange，提问作者Carlos