diff --git a/CMakeLists.txt b/CMakeLists.txt
index c55827a..8b23c20 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -13,9 +13,9 @@ set(_CMAKE_MAP_IMPORTED_CONFIG_MINSIZEREL ${CMAKE_MAP_IMPORTED_CONFIG_MINSIZEREL
 set(_CMAKE_MAP_IMPORTED_CONFIG_RELWITHDEBINFO ${CMAKE_MAP_IMPORTED_CONFIG_RELWITHDEBINFO})
 set(_CMAKE_MAP_IMPORTED_CONFIG_RELEASE ${CMAKE_MAP_IMPORTED_CONFIG_RELEASE})
 
-set(CMAKE_MAP_IMPORTED_CONFIG_MINSIZEREL "")
-set(CMAKE_MAP_IMPORTED_CONFIG_RELWITHDEBINFO "")
-set(CMAKE_MAP_IMPORTED_CONFIG_RELEASE "")
+unset(CMAKE_MAP_IMPORTED_CONFIG_MINSIZEREL)
+unset(CMAKE_MAP_IMPORTED_CONFIG_RELWITHDEBINFO)
+unset(CMAKE_MAP_IMPORTED_CONFIG_RELEASE)
 
 # find Python before include mo2-cmake, otherwise this will trigger a bunch of CMP0111
 # due to the imported configuration mapping variables defined in mo2.cmake