Using Host and Build Profile from CMakePresets

[ibis-hdl]

I like to start with the positive things: it works as intended, but if you have other ideas, problems rises as usually :)
Anyway, I use CMakePresets.json in that way:

{
    ...
    "configurePresets": [
        {
            "name": "conan-provider",
            "hidden": true,
            "cacheVariables": {
                "CMAKE_PROJECT_TOP_LEVEL_INCLUDES": "${sourceDir}/cmake/cmake-conan/conan_provider.cmake"
            }
        },

where I clone the git repo cmake-conan into ${sourceDir}/cmake/cmake-conan and inherits to all my presets, which works as expected.
To support macOS users with clang and libc++ on my Linux box, I have a special target clang-libc++ (since I don't own a Mac).

My intention is to use cmake-conan with this CMake preset.

The first step was to write a default profile for conan:

$ cat ~/.conan2/profiles/default 
[settings]
arch=x86_64
build_type=Release
compiler=clang
compiler.cppstd=gnu17
compiler.libcxx=libc++
compiler.version=18
os=Linux

[buildenv]
CC=clang
CXX=clang++

[conf]
tools.build:compiler_executables={ "c": "/usr/bin/clang", "cpp": "/usr/bin/clang++" }

The conan provider should take this into account for host and build profile, but doesn't.

Second try, I wrote a CMake cache file clang-libc++-cachevars.cmake:

# pre-fill
set(CONAN_HOST_PROFILE:STRING  "clang-libc++")
set(CONAN_BUILD_PROFILE:STRING "clang-libc++")

to inject this into the CMake cache as it is done with the CMakePresets.json from above, and call it:

$ cmake -C clang-libc++-cachevars.cmake --preset clang-libc++-release
loading initial cache file clang-libc++-cachevars.cmake
Preset CMake variables:

  CMAKE_BUILD_TYPE="Release"
  CMAKE_CONFIGURATION_TYPES="Debug;Release;RelWithDebInfo"
  CMAKE_CXX_COMPILER="clang++"
  CMAKE_C_COMPILER="clang"
  CMAKE_DEFAULT_BUILD_TYPE="Release"
...
-- CMake-Conan: Checking if a default profile exists
/home/vscode/.conan2/profiles/default
-- CMake-Conan: cmake_system_name=Linux
-- CMake-Conan: cmake_system_processor=x86_64
-- CMake-Conan: CMake compiler=Clang
-- CMake-Conan: CMake compiler version=18.1.3
-- CMake-Conan: [settings] compiler=clang
-- CMake-Conan: [settings] compiler.version=18
-- Performing Test _conan_is_libcxx
-- Performing Test _conan_is_libcxx - Failed
-- Performing Test _conan_is_gnu_libstdcxx
-- Performing Test _conan_is_gnu_libstdcxx - Success
...
-- CMake-Conan: Creating profile /workspaces/gh-actions-test/build/conan_host_profile
-- CMake-Conan: Profile: 
[settings]
arch=x86_64
os=Linux
compiler=clang
compiler.version=18
compiler.cppstd=20
compiler.libcxx=libstdc++11
[conf]
tools.cmake.cmaketoolchain:generator=Ninja Multi-Config
tools.build:compiler_executables={"c":"clang","cpp":"/usr/bin/clang++"}

-- CMake-Conan: Installing both Debug and Release
-- CMake-Conan: conan install /workspaces/gh-actions-test -of=/workspaces/gh-actions-test/build/conan --profile:host=default;--profile:host=/workspaces/gh-actions-test/build/conan_host_profile;--profile:build=default;-s;build_type=Release;--build=missing

======== Input profiles ========
Profile host:
[settings]
arch=x86_64
build_type=Release
compiler=clang
compiler.cppstd=20
compiler.libcxx=libstdc++11
compiler.version=18
os=Linux
[conf]
tools.build:compiler_executables={'c': 'clang', 'cpp': '/usr/bin/clang++'}
tools.cmake.cmaketoolchain:generator=Ninja Multi-Config
[buildenv]
CC=clang
CXX=clang++

Profile build:
[settings]
arch=x86_64
build_type=Release
compiler=clang
compiler.cppstd=gnu17
compiler.libcxx=libc++
compiler.version=18
os=Linux
[conf]
tools.build:compiler_executables={'c': '/usr/bin/clang', 'cpp': '/usr/bin/clang++'}
[buildenv]
CC=clang
CXX=clang++
...
$ cmake -C clang-libc++-cachevars.cmake --build --preset clang-libc++-release
...

Finally, the provider is always creating the build profile:

-- CMake-Conan: Creating profile /home/runner/work/gh-actions-test/gh-actions-test/build/conan_host_profile
-- CMake-Conan: Profile: 
[settings]
arch=x86_64
os=Linux
compiler=clang
compiler.version=18
compiler.cppstd=20
compiler.libcxx=libstdc++11
[conf]
tools.cmake.cmaketoolchain:generator=Ninja Multi-Config
tools.build:compiler_executables={"c":"clang","cpp":"/usr/bin/clang++"}

-- CMake-Conan: Installing both Debug and Release
-- CMake-Conan: conan install /home/runner/work/gh-actions-test/gh-actions-test -of=/home/runner/work/gh-actions-test/gh-actions-test/build/conan --profile:host=default;--profile:host=/home/runner/work/gh-actions-test/gh-actions-test/build/conan_host_profile;--profile:build=default;-s;build_type=Release;--build=missing

======== Input profiles ========
Profile host:
[settings]
arch=x86_64
build_type=Release
compiler=clang
compiler.cppstd=20
compiler.libcxx=libstdc++11
compiler.version=18
os=Linux
[conf]
tools.build:compiler_executables={'c': 'clang', 'cpp': '/usr/bin/clang++'}
tools.cmake.cmaketoolchain:generator=Ninja Multi-Config

Profile build:
[settings]
arch=x86_64
build_type=Release
compiler=clang
compiler.cppstd=20
compiler.libcxx=libc++
compiler.version=18
os=Linux

and the CMakeCache.txt contains always:

...
//Conan build profile
CONAN_BUILD_PROFILE:STRING=default
...

//Conan host profile
CONAN_HOST_PROFILE:STRING=default;auto-cmake

//Command line arguments for conan install
CONAN_INSTALL_ARGS:STRING=--build=missing
...

To me, it looks as the variables CONAN_BUILD_PROFILEand CONAN_HOST_PROFILEaren't honored as described in the docs, isn't it or do I use it not in the right way?

[ibis-hdl]

I found a smart solution, which finally doesn't work as expected.

$ conan profile show -pr clang-libc++
Host profile:
[settings]
arch=x86_64
build_type=Release
compiler=clang
compiler.cppstd=gnu17
compiler.libcxx=libc++
compiler.version=18
os=Linux
[conf]
tools.build:compiler_executables={'c': '/usr/bin/clang', 'cpp': '/usr/bin/clang++'}
[buildenv]
CC=clang
CXX=clang++

Build profile:
[settings]
arch=x86_64
build_type=Release
compiler=clang
compiler.cppstd=gnu17
compiler.libcxx=libc++
compiler.version=18
os=Linux
[conf]
tools.build:compiler_executables={'c': '/usr/bin/clang', 'cpp': '/usr/bin/clang++'}
[buildenv]
CC=clang
CXX=clang++

And CMakePresets.json

{
    ...
    "configurePresets": [
        {
            "name": "conan-provider",
            "hidden": true,
            "cacheVariables": {
                "CMAKE_PROJECT_TOP_LEVEL_INCLUDES": "${sourceDir}/cmake/cmake-conan/conan_provider.cmake"
            }
        },
        ...
        {
            "name": "clang-libc++",
            "inherits": [
                ...
                "conan-provider",
                ...
            ],
            "cacheVariables": {
                "CONAN_HOST_PROFILE": "clang-libc++",
                "CONAN_BUILD_PROFILE": "clang-libc++"            }
        },
        ...

With this, CMakeCache variables are set expected, but CMake build failed for some reason.

$ cmake --preset clang-libc++
Preset CMake variables:

  CMAKE_BUILD_TYPE="Release"
  CMAKE_CONFIGURATION_TYPES="Debug;Release;RelWithDebInfo"
  CMAKE_CXX_COMPILER="clang++"
  CMAKE_C_COMPILER="clang"
  CMAKE_DEFAULT_BUILD_TYPE="Release"
  ...
  CMAKE_PROJECT_TOP_LEVEL_INCLUDES="/workspaces/gh-actions-test/cmake/cmake-conan/conan_provider.cmake"
  CONAN_BUILD_PROFILE="clang-libc++"
  CONAN_HOST_PROFILE="clang-libc++"
...
-- The CXX compiler identification is Clang 18.1.3
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/clang++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- CMake-Conan: first find_package() found. Installing dependencies with Conan
-- CMake-Conan: Installing both Debug and Release
-- CMake-Conan: conan install /workspaces/gh-actions-test -of=/workspaces/gh-actions-test/build/conan --profile:host=clang-libc++;--profile:build=clang-libc++;-s;build_type=Release;--build=missing

======== Input profiles ========
Profile host:
[settings]
arch=x86_64
build_type=Release
compiler=clang
compiler.cppstd=gnu17
compiler.libcxx=libc++
compiler.version=18
os=Linux
[conf]
tools.build:compiler_executables={'c': '/usr/bin/clang', 'cpp': '/usr/bin/clang++'}
[buildenv]
CC=clang
CXX=clang++

Profile build:
[settings]
arch=x86_64
build_type=Release
compiler=clang
compiler.cppstd=gnu17
compiler.libcxx=libc++
compiler.version=18
os=Linux
[conf]
tools.build:compiler_executables={'c': '/usr/bin/clang', 'cpp': '/usr/bin/clang++'}
[buildenv]
CC=clang
CXX=clang++


======== Computing dependency graph ========
Graph root
    conanfile.py: /workspaces/gh-actions-test/conanfile.py
Requirements
    catch2/3.7.1#431d772165ed0bc5adaabaa44a9f53ca - Cache

======== Computing necessary packages ========
Requirements
    catch2/3.7.1#431d772165ed0bc5adaabaa44a9f53ca:33ee53aab1b9bfd22e13914fa502a98606b452d9#e5783f218c56ede35621a61c9e45edc5 - Cache

======== Installing packages ========
catch2/3.7.1: Already installed! (1 of 1)
WARN: deprecated: Usage of deprecated Conan 1.X features that will be removed in Conan 2.X:
WARN: deprecated:     'cpp_info.filenames' used in: catch2/3.7.1
WARN: deprecated:     'cpp_info.names' used in: catch2/3.7.1
WARN: deprecated:     'cpp_info.build_modules' used in: catch2/3.7.1

======== Finalizing install (deploy, generators) ========
conanfile.py: Calling generate()
conanfile.py: Generators folder: /workspaces/gh-actions-test/build/conan/build/Release/generators
conanfile.py: CMakeDeps necessary find_package() and targets for your CMakeLists.txt
    find_package(Catch2)
    target_link_libraries(... Catch2::Catch2WithMain)
conanfile.py: CMakeToolchain generated: conan_toolchain.cmake
conanfile.py: CMakeToolchain: Preset 'conan-release' added to CMakePresets.json.
    (cmake>=3.23) cmake --preset conan-release
    (cmake<3.23) cmake <path> -G "Unix Makefiles" -DCMAKE_TOOLCHAIN_FILE=generators/conan_toolchain.cmake  -DCMAKE_POLICY_DEFAULT_CMP0091=NEW -DCMAKE_BUILD_TYPE=Release
conanfile.py: CMakeToolchain generated: /workspaces/gh-actions-test/build/conan/build/Release/generators/CMakePresets.json
conanfile.py: CMakeToolchain generated: /workspaces/gh-actions-test/ConanCMakePresets.json
conanfile.py: Generating aggregated env files
conanfile.py: Generated aggregated env files: ['conanbuild.sh', 'conanrun.sh']
Install finished successfully
-- CMake-Conan: CONAN_GENERATORS_FOLDER=/workspaces/gh-actions-test/build/conan/build/Release/generators
-- CMake-Conan: CONANFILE=/workspaces/gh-actions-test/conanfile.py
-- CMake-Conan: conan install /workspaces/gh-actions-test -of=/workspaces/gh-actions-test/build/conan --profile:host=clang-libc++;--profile:build=clang-libc++;-s;build_type=Debug;--build=missing

======== Input profiles ========
Profile host:
[settings]
arch=x86_64
build_type=Debug
compiler=clang
compiler.cppstd=gnu17
compiler.libcxx=libc++
compiler.version=18
os=Linux
[conf]
tools.build:compiler_executables={'c': '/usr/bin/clang', 'cpp': '/usr/bin/clang++'}
[buildenv]
CC=clang
CXX=clang++

Profile build:
[settings]
arch=x86_64
build_type=Release
compiler=clang
compiler.cppstd=gnu17
compiler.libcxx=libc++
compiler.version=18
os=Linux
[conf]
tools.build:compiler_executables={'c': '/usr/bin/clang', 'cpp': '/usr/bin/clang++'}
[buildenv]
CC=clang
CXX=clang++


======== Computing dependency graph ========
Graph root
    conanfile.py: /workspaces/gh-actions-test/conanfile.py
Requirements
    catch2/3.7.1#431d772165ed0bc5adaabaa44a9f53ca - Cache

======== Computing necessary packages ========
Requirements
    catch2/3.7.1#431d772165ed0bc5adaabaa44a9f53ca:9976135ac672b25daf671f2b7a42dcb840fc7db9#6446d545cd569e43f6f07f32b7c42dc3 - Cache

======== Installing packages ========
catch2/3.7.1: Already installed! (1 of 1)
WARN: deprecated: Usage of deprecated Conan 1.X features that will be removed in Conan 2.X:
WARN: deprecated:     'cpp_info.filenames' used in: catch2/3.7.1
WARN: deprecated:     'cpp_info.names' used in: catch2/3.7.1
WARN: deprecated:     'cpp_info.build_modules' used in: catch2/3.7.1

======== Finalizing install (deploy, generators) ========
conanfile.py: Calling generate()
conanfile.py: Generators folder: /workspaces/gh-actions-test/build/conan/build/Debug/generators
conanfile.py: CMakeDeps necessary find_package() and targets for your CMakeLists.txt
    find_package(Catch2)
    target_link_libraries(... Catch2::Catch2WithMain)
conanfile.py: CMakeToolchain generated: conan_toolchain.cmake
conanfile.py: CMakeToolchain: Preset 'conan-debug' added to CMakePresets.json.
    (cmake>=3.23) cmake --preset conan-debug
    (cmake<3.23) cmake <path> -G "Unix Makefiles" -DCMAKE_TOOLCHAIN_FILE=generators/conan_toolchain.cmake  -DCMAKE_POLICY_DEFAULT_CMP0091=NEW -DCMAKE_BUILD_TYPE=Debug
conanfile.py: CMakeToolchain generated: /workspaces/gh-actions-test/build/conan/build/Debug/generators/CMakePresets.json
conanfile.py: CMakeToolchain generated: /workspaces/gh-actions-test/ConanCMakePresets.json
conanfile.py: Generating aggregated env files
conanfile.py: Generated aggregated env files: ['conanbuild.sh', 'conanrun.sh']
Install finished successfully
-- CMake-Conan: CONAN_GENERATORS_FOLDER=/workspaces/gh-actions-test/build/conan/build/Debug/generators
-- CMake-Conan: CONANFILE=/workspaces/gh-actions-test/conanfile.py
-- Conan: Component target declared 'Catch2::Catch2'
-- Conan: Component target declared 'Catch2::Catch2WithMain'
-- Configuring done (1.8s)
-- Generating done (0.6s)
-- Build files have been written to: /workspaces/gh-actions-test/build

and build:

 $ cmake --build --preset clang-libc++-release
[1/8 (0.082s)] Scanning /workspaces/gh-actions-test/testsuite/test_me.cpp for CXX dependencies
FAILED: testsuite/CMakeFiles/gh-action-test_unit_tests.dir/Release/test_me.cpp.o.ddi 
"/usr/bin/clang-scan-deps-18" -format=p1689 -- /usr/bin/clang++ -DCMAKE_INTDIR=\"Release\" -I/workspaces/gh-actions-test/src -O3 -DNDEBUG -std=c++20 -x c++ /workspaces/gh-actions-test/testsuite/test_me.cpp -c -o testsuite/CMakeFiles/gh-action-test_unit_tests.dir/Release/test_me.cpp.o -resource-dir "/usr/lib/llvm-18/lib/clang/18" -MT testsuite/CMakeFiles/gh-action-test_unit_tests.dir/Release/test_me.cpp.o.ddi -MD -MF testsuite/CMakeFiles/gh-action-test_unit_tests.dir/Release/test_me.cpp.o.ddi.d > testsuite/CMakeFiles/gh-action-test_unit_tests.dir/Release/test_me.cpp.o.ddi.tmp && mv testsuite/CMakeFiles/gh-action-test_unit_tests.dir/Release/test_me.cpp.o.ddi.tmp testsuite/CMakeFiles/gh-action-test_unit_tests.dir/Release/test_me.cpp.o.ddi
Error while scanning dependencies for /workspaces/gh-actions-test/testsuite/test_me.cpp:
/workspaces/gh-actions-test/testsuite/test_me.cpp:1:10: fatal error: 'catch2/catch_test_macros.hpp' file not found
[2/8 (0.138s)] Scanning /workspaces/gh-actions-test/source/main.cpp for CXX dependencies
ninja: build stopped: subcommand failed.

The output directory for Conan is default, the recipe isn't any special

class CompressorRecipe(ConanFile):
    settings = "os", "compiler", "build_type", "arch"

    def requirements(self):
        self.requires("catch2/3.7.1")

    def layout(self):
        cmake_layout(self)

    def generate(self):
        deps = CMakeDeps(self)
        deps.generate()
        tc = CMakeToolchain(self)
        tc.user_presets_path = "ConanCMakePresets.json"
        tc.generate()

[ibis-hdl]

During reducing the problem, it compiles now for some circumstances. I'm not sure what the problem is, but it seems to be related to selected compiler by Conan and/or the profile...
Anyway, here a striped down version of this repo.

I continued with my experiments:

> conan remove '*'
...
> rm -rf build; CMAKE_CXX_COMPILER=clang++ CXX=clang++ cmake --preset clang-libc++
...
-- The C compiler identification is GNU 13.2.0
-- The CXX compiler identification is Clang 18.1.3
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - failed
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc - broken
CMake Error at /opt/cmake/share/cmake-3.30/Modules/CMakeTestCCompiler.cmake:67 (message):
  The C compiler

    "/usr/bin/cc"

  is not able to compile a simple test program.
...
> conan list 'catch*/*:*' --format=compact
Local Cache
  catch2/3.7.1
    catch2/3.7.1#431d772165ed0bc5adaabaa44a9f53ca%1726584452.35 (2024-09-17 14:47:32 UTC)
      catch2/3.7.1#431d772165ed0bc5adaabaa44a9f53ca:33ee53aab1b9bfd22e13914fa502a98606b452d9
        settings: Linux, x86_64, Release, clang, gnu17, libc++, 18
        options(diff): 
      catch2/3.7.1#431d772165ed0bc5adaabaa44a9f53ca:9976135ac672b25daf671f2b7a42dcb840fc7db9
        settings: Linux, x86_64, Debug, clang, gnu17, libc++, 18
        options(diff): 

So Conan related settings seems to be correct to me :(

But:

> rm -rf build; CC=clang CXX=clang++ cmake --preset clang-libc++ 
...
# all fine with explicit given CC - even unused !!!!!
> cmake --build --preset clang-libc++-release
...
Error while scanning dependencies for /workspaces/conan-cmake-issue/testsuite/test_me.cpp:
/workspaces/conan-cmake-issue/testsuite/test_me.cpp:1:10: fatal error: 'catch2/catch_test_macros.hpp' file not found
[2/8] Scanning /workspaces/conan-cmake-issue/source/main.cpp for CXX dependencies
ninja: build stopped: subcommand failed.

Anyway, somewhere I've got lost ... I created a branch conan-explicit with call of conan install (without conan-cmake) and failed completely now :(