diff --git a/cmake/libraries/sdl.cmake b/cmake/libraries/sdl.cmake
index 4fa044e6..28c268af 100644
--- a/cmake/libraries/sdl.cmake
+++ b/cmake/libraries/sdl.cmake
@@ -9,6 +9,8 @@ endif()
 
 if(USE_INTERNAL_SDL AND HAVE_INTERNAL_SDL)
     set(SDL2_INCLUDE_DIRS ${INTERNAL_SDL_DIR}/include)
+    list(APPEND CLIENT_DEFINITIONS USE_INTERNAL_SDL_HEADERS)
+    list(APPEND RENDERER_DEFINITIONS USE_INTERNAL_SDL_HEADERS)
 
     if(WIN32)
         if(ARCH STREQUAL "x86_64")