diff --git a/include/battle_util.h b/include/battle_util.h
index 1eacdaa03d5b..dba6299dee6d 100644
--- a/include/battle_util.h
+++ b/include/battle_util.h
@@ -152,6 +152,7 @@ struct DamageCalculationData
     u32 updateFlags:1;
     u32 padding:2;
 };
+STATIC_ASSERT(sizeof(struct DamageCalculationData) <= 4, StructExceedsFourBytes);
 
 void HandleAction_ThrowBall(void);
 bool32 IsAffectedByFollowMe(u32 battlerAtk, u32 defSide, u32 move);