diff --git a/lib/irrlicht/CMakeLists.txt b/lib/irrlicht/CMakeLists.txt
index 30b4b2955..2dd3d80a5 100644
--- a/lib/irrlicht/CMakeLists.txt
+++ b/lib/irrlicht/CMakeLists.txt
@@ -58,12 +58,12 @@ if(NOT SERVER_ONLY)
         endif()        
     endif()
 else()
-    include_directories("${CMAKE_CURRENT_SOURCE_DIR}/include/"
-                        "${ZLIB_INCLUDE_DIR}")
+    include_directories("${CMAKE_CURRENT_SOURCE_DIR}/include/")
     if(MSVC OR APPLE)
         include_directories("${CMAKE_CURRENT_BINARY_DIR}/../zlib/")
     else()
         find_package(ZLIB REQUIRED)
+        include_directories("${ZLIB_INCLUDE_DIR}")
     endif()
     add_definitions(-DNO_IRR_COMPILE_WITH_LIBPNG_)
     add_definitions(-DNO_IRR_COMPILE_WITH_LIBJPEG_)