How does CMake handle shared-library upgrades? - c++

Question

I have a project where I link to boost; the CMakeLists.txt looks like this:
project(test VERSION 1.0)
set(CMAKE_CXX_COMPILER /usr/bin/g++)
set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED True)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g3 -Wall -Wextra -Wfloat-equal -Wundef -Wcast-align -Wwrite-strings -Wlogical-op -Wredundant-decls -Wshadow -Woverloaded-virtual")
find_package(Boost COMPONENTS filesystem program_options log log_setup REQUIRED)
include_directories(
${Boost_INCLUDE_DIRS}
)
add_executable(test src/test.cpp)
target_link_libraries(test
LINK_PUBLIC
${Boost_LIBRARIES}
config++
)
install(TARGETS test DESTINATION /usr/bin)
Now I am stumped how the linking in CMake works under the hood. It compiles fine but after I upgraded Boost, I am getting the error
test: error while loading shared libraries: libboost_program_options.so.1.75.0: cannot open shared object file: No such file or directory
and I'd like to avoid having to recompile every time a library gets an update.
The CMake doc says that
The LINK_PUBLIC and LINK_PRIVATE modes can be used to specify both the link dependencies and the link interface in one command.
But I don't quite understand how or why CMake links to the specific version of Boost and not simply to /usr/lib/libboost_program_options.so which is just a symlink to the currently installed version.