diff --git a/asm/src/main/kotlin/org/openrs2/asm/packclass/ConstantPool.kt b/asm/src/main/kotlin/org/openrs2/asm/packclass/ConstantPool.kt
index 91f0469810..d1e0b5f043 100644
--- a/asm/src/main/kotlin/org/openrs2/asm/packclass/ConstantPool.kt
+++ b/asm/src/main/kotlin/org/openrs2/asm/packclass/ConstantPool.kt
@@ -160,6 +160,8 @@ public class ConstantPool private constructor(
                 }
             }
 
+            check(!it.hasNext())
+
             return ConstantPool(
                 stringArray,
                 fieldNamesAndTypes.toTypedArray(),