diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9be304d..8e07aa8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -58,7 +58,7 @@ ENDIF(MSVC)
 LIST(REMOVE_DUPLICATES SDL2_ALL_INCLUDE_DIRS)
 
 INCLUDE_DIRECTORIES(BEFORE ${PROJECT_SOURCE_DIR})
-INCLUDE_DIRECTORIES(${SDL2_ALL_INCLUDE_DIRS})
+INCLUDE_DIRECTORIES(SYSTEM ${SDL2_ALL_INCLUDE_DIRS})
 
 IF(SDL2PP_WITH_WERROR)
 	SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WERROR_FLAG}")