fix overriding by setup.py such that install now works again

CMakeLists.txt

@@ -10,7 +10,7 @@ add_subdirectory(resources/pybind11)
 configure_file(${CMAKE_CURRENT_SOURCE_DIR}/src/config.h.in ${CMAKE_CURRENT_BINARY_DIR}/src/generated/config.h) 
 
 
-set(STORMPY_LIB_DIR "${CMAKE_SOURCE_DIR}/lib/stormpy")
+set(STORMPY_LIB_DIR "${CMAKE_SOURCE_DIR}/lib/stormpy" CACHE STRING "Sets the storm library dir")
 
 function(stormpy_module NAME)
     # second, optional argument is LIBRARY_OUTPUT_DIRECTORY,

setup.py

@@ -44,7 +44,8 @@ class CMakeBuild(build_ext):
 
     def build_extension(self, ext):
         extdir = os.path.abspath(os.path.dirname(self.get_ext_fullpath(ext.name)))
-        cmake_args = ['-DCMAKE_LIBRARY_OUTPUT_DIRECTORY=' + os.path.join(extdir, ext.subdir),
+        print(extdir)
+        cmake_args = ['-DSTORMPY_LIB_DIR=' + extdir,
                       '-DPYTHON_EXECUTABLE=' + sys.executable]
             
         cfg = 'Release'  # if self.debug else 'Release'