diff --git a/src/script/condition/trait_condition.h b/src/script/condition/trait_condition.h
index ff4bb1208..64cd919bf 100644
--- a/src/script/condition/trait_condition.h
+++ b/src/script/condition/trait_condition.h
@@ -41,6 +41,7 @@ class trait_condition final : public condition
 
 	virtual bool check(const CPlayer *player, const read_only_context &ctx, const bool ignore_units) const override
 	{
+		Q_UNUSED(player)
 		Q_UNUSED(ctx)
 		Q_UNUSED(ignore_units)