diff --git a/CMakeLists.txt b/CMakeLists.txt
index 597a7de..38bd7f4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2,6 +2,10 @@ project(dbusmenu-qt)
 cmake_minimum_required(VERSION 2.8.11)
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake/modules")
 
+if (POLICY CMP0021)
+  cmake_policy(SET CMP0021 WARN)
+endif (POLICY CMP0021)
+
 # Build options
 option(WITH_DOC "Build documentation (requires Doxygen)" ON)