target_link_libraries using absolute path

[XgDuan]

I am working on a c++ extension that using a third-party c++ dynamic library (assume its name as libthirdparty.so), and my project folder looks like:

|- api
|  |- include
|  |   |- thirdparty.h
|  |- lib
|  |   |- libthirdparty.so
|- build
|- pybind11
|- src
|  |- main.src
|- CMakeList.txt
|- setup.py

As I am using CMake to build my project, link a third-party library would be like:

add_library(thirdparty SHARED IMPORTED) 
set_target_properties(thirtparty PROPERTIES
  IMPORTED_LOCATION "/absolute_path_to_my_project/api/lib/libthirdparty.so"
)
target_link_libraries(my_proj PRIVATE thirdparty)

However, CMake(pybind11) may use relative path (relative to the build location) when link the third-party library. Then after setuptools copies the generated my_proj.cpythonxxxx.so to python's site-packages, I would encounter the following error when I try to import the lib (python -c "import my_proj"):

ImportError: ../../../api/lib/libthirdparty.so: cannot open shared object file: No such file or directory

For that CMake build the project under some folder like build/tmp.xxx/my_proj, then the path is resolved as ../../../api.... Even worse, when setuptool copies my_proj.cpythonxxxx.so to site-packages, the relative path becomes even ridiculous.

I am not familiar with CMake and have tried several CMake commands (from Google) and all of them fail. So, maybe someone here could help me, and I do think there should be a very simple solution.