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cmake_find_package_multi

Warning

This is an experimental feature subject to breaking changes in future releases.

This is the reference page for cmake_find_package_multi generator. Go to Integrations/CMake<cmake> if you want to learn how to integrate your project or recipes with CMake.

Generated files

For each conan package in your graph, it will generate 2 files and 1 more per different build_type. Being <PKG-NAME> the package name used in the reference (by default) or the one declared in cpp_info.name or in cpp_info.names["cmake_find_package_multi"] if specified:

NAME CONTENTS
<PKG-NAME>Config.cmake It includes the <PKG-NAME>Targets.cmake and call find_dependency for each dep
<PKG-NAME>ConfigVersion.cmake Package version file for each dep
<PKG-NAME>Targets.cmake It includes the files <PKG-NAME>Targets-<BUILD-TYPE>.cmake
<PKG-NAME>Targets-debug.cmake Specific information for the Debug configuration
<PKG-NAME>Targets-release.cmake Specific information for the Release configuration
<PKG-NAME>Targets-relwithdebinfo.cmake Specific information for the RelWithDebInfo configuration
<PKG-NAME>Targets-minsizerel.cmake Specific information for the MinSizeRel configuration

Targets

A target named <PKG-NAME>::<PKG-NAME> target is generated with the following properties adjusted:

  • INTERFACE_INCLUDE_DIRECTORIES: Containing all the include directories of the package.
  • INTERFACE_LINK_LIBRARIES: Library paths to link.
  • INTERFACE_COMPILE_DEFINITIONS: Definitions of the library.
  • INTERFACE_COMPILE_OPTIONS: Compile options of the library.

The targets contains multi-configuration properties, for example, the compile options property is declared like this:

set_property(TARGET <PKG-NAME>::<PKG-NAME>
         PROPERTY INTERFACE_COMPILE_OPTIONS
             $<$<CONFIG:Release>:${{<PKG-NAME>_COMPILE_OPTIONS_RELEASE_LIST}}>
             $<$<CONFIG:RelWithDebInfo>:${{<PKG-NAME>_COMPILE_OPTIONS_RELWITHDEBINFO_LIST}}>
             $<$<CONFIG:MinSizeRel>:${{<PKG-NAME>_COMPILE_OPTIONS_MINSIZEREL_LIST}}>
             $<$<CONFIG:Debug>:${{<PKG-NAME>_COMPILE_OPTIONS_DEBUG_LIST}}>)

The targets are also transitive. So, if your project depends on a packages A and B, and at the same time A depends on C, the A target will contain automatically the properties of the C dependency, so in your CMakeLists.txt file you only need to find_package(A CONFIG) and find_package(B CONFIG).

Important

Add the CONFIG option to find_package so that module mode is explicitly skipped by CMake. This helps to solve issues when there is for example a Find<PKG-NAME>.cmake file in CMake's default modules directory that could be loaded instead of the <PKG-NAME>Config.cmake generated by Conan.

You also need to adjust CMAKE_PREFIX_PATH and CMAKE_MODULE_PATH so CMake can locate all the <PKG-NAME>Config.cmake files: The CMAKE_PREFIX_PATH is used by the find_package and the CMAKE_MODULE_PATH is used by the find_dependency calls that locates the transitive dependencies.

The <PKG-NAME>Targets-.cmake files use <PKG-NAME>_BUILD_MODULES_<BUILD-TYPE> values to include the files using the include(...) CMake directive. This makes functions or utilities exported by the package available for consumers just by setting find_package(<PKG-NAME>) in the CMakeLists.txt.

Moreover, this also adjusts CMAKE_MODULE_PATH and CMAKE_PREFIX_PATH to the values declared by the package in cpp_info.buildirs, so modules in those directories can be found.

Components

If a recipe uses components <package_information_components>, the targets generated will be <PKG-NAME>::<COMP-NAME> with the following properties adjusted. Being <COMP-NAME> the dictionary key used to declare the component or the one declared in cpp_info.name or the alternative name declared in cpp_info.components["comp_name"].names["cmake_find_package_multi"] if specified:

  • INTERFACE_INCLUDE_DIRECTORIES: Containing all the include directories of the component.
  • INTERFACE_LINK_LIBRARIES: Containing the targets to link the component to (includes component's libraries and dependencies).
  • INTERFACE_COMPILE_DEFINITIONS: Containing the definitions of the component.
  • INTERFACE_COMPILE_OPTIONS: Containing the compile options of the component.

Moreover, a global target <PKG-NAME>::<PKG-NAME> will be declared with the following properties adjusted:

  • INTERFACE_LINK_LIBRARIES: Containing the list of targets for all the components in the package.

Important

If there is a global target shared by different packages, then the global target will be linked to all the components targets across the different packages. This means that the global target will include different components targets across different packages.