diff --git a/extlib/benz/include/picrin/irep.h b/extlib/benz/include/picrin/irep.h
index bba4e2f3..213d0456 100644
--- a/extlib/benz/include/picrin/irep.h
+++ b/extlib/benz/include/picrin/irep.h
@@ -80,6 +80,8 @@ struct pic_irep {
 pic_value pic_analyze(pic_state *, pic_value);
 struct pic_irep *pic_codegen(pic_state *, pic_value);
 
+#if DEBUG
+
 PIC_INLINE void
 pic_dump_code(pic_code c)
 {
@@ -213,6 +215,8 @@ pic_dump_irep(struct pic_irep *irep)
   }
 }
 
+#endif
+
 #if defined(__cplusplus)
 }
 #endif