CMake error on INSTALL(EXPORT ...) when adding a package

[lproj]

Hi,

With regard to the boost example in the CPM.cmake repository, I am trying to add a package right after the CPMAddPackage(NAME Boost ...) line:

set(MQTT_BUILD_EXAMPLES OFF CACHE BOOL "build mqtt_cpp examples" FORCE)
set(MQTT_BUILD_TESTS OFF CACHE BOOL "build mqtt_cpp tests" FORCE)
cpmaddpackage("gh:redboltz/mqtt_cpp#master")

However, I get this error when trying to build the project with cmake (from Ubuntu 22.04):

-- Configuring done
CMake Error: install(EXPORT "mqtt_cpp_ifaceTargets" ...) includes target "mqtt_cpp_iface" which requires target "boost_system" that is not in any export set.
CMake Error: install(EXPORT "mqtt_cpp_ifaceTargets" ...) includes target "mqtt_cpp_iface" which requires target "boost_date_time" that is not in any export set.

Do you know why this happens? It seems to me that the Boost targets do not get exported for some reasons.

Thanks in advance.

[ClausKlein]

see https://discourse.cmake.org/t/install-runtime-dependency-set-appdeps-does-nothing-install/9741/11
and #448

one possible solution, but only with pain: https://github.com/cpm-cmake/CPM.cmake/blob/456c593eb9c24e6a2a96a775bec3feab448a22ce/examples/boost/CMakeLists.txt