diff --git a/src/input_common/sdl/sdl_impl.cpp b/src/input_common/sdl/sdl_impl.cpp
index c5589eb73c..3b5a4a8fcb 100644
--- a/src/input_common/sdl/sdl_impl.cpp
+++ b/src/input_common/sdl/sdl_impl.cpp
@@ -510,7 +510,7 @@ SDLState::~SDLState() {
     }
 }
 
-Common::ParamPackage SDLEventToButtonParamPackage(SDLState& state, const SDL_Event& event) {
+static Common::ParamPackage SDLEventToButtonParamPackage(SDLState& state, const SDL_Event& event) {
     Common::ParamPackage params({{"engine", "sdl"}});
 
     switch (event.type) {