cmake_find_package_multi and version information

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I was writing a Conan recipe for ITK 5 which uses Eigen3 and requires it through the following CMake line (see the corresponding issue for more background information):

find_package(Eigen3 REQUIRED CONFIG)

Long story short, after having bypassed a recipe-specific issue, I managed to get CMake to find the right CMake config file generated with the Conan generator cmake_find_package_multi, but the configuration step eventually failed with the following error:

CMake Error at source_subfolder/Modules/ThirdParty/Eigen3/CMakeLists.txt:56 (find_package):
  Could not find a configuration file for package "Eigen3" that is compatible
  with requested version "3.3".

  The following configuration files were considered but not accepted:

    ~/.conan/data/itk/5.0.1/myteam/stable/build/a9e815bf664154117de467f08af021beb20b7cc4/Eigen3Config.cmake, version: unknown

The recipe I used was that for Eigen 3.3.7, so Conan has the version information, but it seems that this information wasn’t propagated to the files generated by cmake_find_package_multi, triggering the error above.

Would it be possible to forward the version information to the files generated by this generator so that examples like the one above work?

Conan version: 1.19.1 CMake version: 3.10.2

[SSE4]

@lasote yes, sure

[lasote]

Now I have another issue because it looks for Eigen3::Eigen but the target generated is most likely Eigen3::Eigen3. It’s another issue and I’m not sure that there is an easy workaround from the Conan side, I’ll patch my ITK CMake instead.

No, we have a new cppinfo.name but it changes both scope and name: Eigen3XXX::Eigen3XXX at the same time… We tried to create the concept of components in the cppinfo but it is a blocked feature for several different reasons: https://github.com/conan-io/conan/issues/5090