diff --git a/src/table/settings/gui_settings.ini b/src/table/settings/gui_settings.ini
--- a/src/table/settings/gui_settings.ini
+++ b/src/table/settings/gui_settings.ini
@@ -15,9 +15,9 @@ static void InvalidateNewGRFChangeWindow
 static void ZoomMinMaxChanged(int32 new_value);
 static void SpriteZoomMinChanged(int32 new_value);
 
-static std::initializer_list<const char*> _autosave_interval{"off", "monthly", "quarterly", "half year", "yearly"};
-static std::initializer_list<const char*> _osk_activation{"disabled", "double", "single", "immediately"};
-static std::initializer_list<const char*> _savegame_date{"long", "short", "iso"};
+static constexpr std::initializer_list<const char*> _autosave_interval{"off", "monthly", "quarterly", "half year", "yearly"};
+static constexpr std::initializer_list<const char*> _osk_activation{"disabled", "double", "single", "immediately"};
+static constexpr std::initializer_list<const char*> _savegame_date{"long", "short", "iso"};
 
 static const SettingVariant _gui_settings_table[] = {
 [post-amble]