diff --git a/extern/zlib/CMakeLists.txt b/extern/zlib/CMakeLists.txt
index 3487d8c..54f5300 100644
--- a/extern/zlib/CMakeLists.txt
+++ b/extern/zlib/CMakeLists.txt
@@ -37,6 +37,6 @@ else ()
   else ()
     target_compile_options(z PRIVATE -Wno-implicit-fallthrough)
   endif ()
+  target_include_directories(z INTERFACE ${CMAKE_CURRENT_SOURCE_DIR})
   set(ZLIB_LIBRARIES z CACHE STRING "zlib libraries" FORCE)
-  set(ZLIB_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR} CACHE PATH "zlib include directory" FORCE)
 endif ()