NixOS下如何配置Conan使用本地CMake而非自行编译？

问题描述 #

在NixOS上使用Conan 2.5.0安装依赖时，执行conan install conanfile.txt --build=missing遇到错误：Conan自动下载的CMake为动态链接版本，无法在NixOS环境运行。错误日志如下：

➜ conan install conanfile.txt --build=missing
======== Installing packages ========

-------- Downloading 14 packages --------
cmake/3.30.5: Retrieving package 63fead0844576fc02943e16909f08fcdddd6f44b from remote 'conancenter'
cmake/3.30.5: Downloading 44.0MB conan_package.tgz
cmake/3.30.5: Decompressing 44.0MB conan_package.tgz
cmake/3.30.5: Package installed 63fead0844576fc02943e16909f08fcdddd6f44b
cmake/3.30.5: Downloaded package revision e7bca794d221e787672baaed17ddbc3f

# ...

cmake/3.30.5: Appending PATH environment variable: /home/jorge/.conan2/p/cmake472b88369c9bf/p/bin
cmake/3.30.5: Appending PATH environment variable: /home/jorge/.conan2/p/cmake472b88369c9bf/p/bin

# ...

-------- Installing package joltphysics/3.0.1 (21 of 32) --------
joltphysics/3.0.1: Building from source
joltphysics/3.0.1: Package joltphysics/3.0.1:3f7fd406790cc7bc8b3903b7793684e958c409a3
joltphysics/3.0.1: Copying sources to build folder
joltphysics/3.0.1: Building your package in /home/jorge/.conan2/p/b/joltpc788376fa4e1a/b
joltphysics/3.0.1: Calling generate()
joltphysics/3.0.1: Generators folder: /home/jorge/.conan2/p/b/joltpc788376fa4e1a/b/build/Release/generators
joltphysics/3.0.1: CMakeToolchain generated: conan_toolchain.cmake
joltphysics/3.0.1: CMakeToolchain generated: /home/jorge/.conan2/p/b/joltpc788376fa4e1a/b/build/Release/generators/CMakePresets.json
joltphysics/3.0.1: Generating aggregated env files
joltphysics/3.0.1: Generated aggregated env files: ['conanbuild.sh', 'conanrun.sh']
joltphysics/3.0.1: Calling build()
joltphysics/3.0.1: Apply patch (conan): Fix CMakeLists: no warnings as errors, allow shared, add install target, and add profile & debug_renderer options
joltphysics/3.0.1: Running CMake.configure()
joltphysics/3.0.1: RUN: cmake -G "Unix Makefiles" -DCMAKE_TOOLCHAIN_FILE="generators/conan_toolchain.cmake" -DCMAKE_INSTALL_PREFIX="/home/jorge/.conan2/p/b/joltpc788376fa4e1a/p" -DCMAKE_POLICY_DEFAULT_CMP0091="NEW" -DCMAKE_BUILD_TYPE="Release" "/home/jorge/.conan2/p/b/joltpc788376fa4e1a/b/src/Build"
Could not start dynamically linked executable: cmake
NixOS cannot run dynamically linked executables intended for generic
linux environments out of the box. For more information, see:
https://nix.dev/permalink/stub-ld

joltphysics/3.0.1: ERROR:
Package '3f7fd406790cc7bc8b3903b7793684e958c409a3' build failed
joltphysics/3.0.1: WARN: Build folder /home/jorge/.conan2/p/b/joltpc788376fa4e1a/b/build/Release
ERROR: joltphysics/3.0.1: Error in build() method, line 141
    cmake.configure(build_script_folder=os.path.join(self.source_folder, "Build"))
    ConanException: Error 127 while executing

当前Conan profile：

➜  conan profile show
Host profile:
[settings]
arch=x86_64
build_type=Release
compiler=gcc
compiler.cppstd=gnu17
compiler.libcxx=libstdc++11
compiler.version=13
os=Linux

Build profile:
[settings]
arch=x86_64
build_type=Release
compiler=gcc
compiler.cppstd=gnu17
compiler.libcxx=libstdc++11
compiler.version=13
os=Linux

项目conanfile.txt内容：

[requires]
eastl/3.21.12
joltphysics/3.0.1
diligent-core/api.252009

[generators]
CMakeDeps

解决方案 #

1. 确认本地CMake路径 #

先获取NixOS上已安装CMake的绝对路径：

which cmake

通常输出为/run/current-system/sw/bin/cmake（系统级安装）或~/.nix-profile/bin/cmake（用户级安装）。

2. 配置Conan使用本地CMake #

有两种常用方式：

方式一：修改Conan Profile（永久生效）

编辑默认Profile文件（~/.conan2/profiles/default），在文件末尾添加以下配置，替换为你实际获取到的CMake路径：

[conf]
tools.cmake.cmaketoolchain:cmake_program=/run/current-system/sw/bin/cmake

[buildenv]
PATH=/run/current-system/sw/bin:$PATH

方式二：执行命令时临时指定（单次生效）

在conan install命令中直接通过-c参数指定CMake路径：

conan install conanfile.txt --build=missing -c tools.cmake.cmaketoolchain:cmake_program=$(which cmake)

3. 验证配置 #

重新执行conan install命令，此时Conan会跳过下载cmake包，直接使用你本地安装的3.29.2版本进行依赖构建。

内容的提问来源于stack exchange，提问作者shackra