diff --git a/compile.c b/compile.c
index fd0af93c76..5ba4af476a 100644
--- a/compile.c
+++ b/compile.c
@@ -8062,7 +8062,7 @@ iseq_ibf_dump(const rb_iseq_t *iseq, VALUE opt)
 
     if (RTEST(opt)) {
 	VALUE opt_str = rb_check_string_type(opt);
-	header.extra_size = (unsigned int)RSTRING_LEN(opt_str) + 1;
+	header.extra_size = RSTRING_LENINT(opt_str) + 1;
 	ibf_dump_write(&dump, RSTRING_PTR(opt_str), header.extra_size);
     }
     else {
diff --git a/vm_core.h b/vm_core.h
index 8c6456abda..89a242acc6 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -410,18 +410,18 @@ struct rb_iseq_struct {
 
 #if USE_LAZY_LOAD
 const rb_iseq_t *rb_iseq_complete(const rb_iseq_t *iseq);
+#endif
 
 static inline const rb_iseq_t *
 rb_iseq_check(const rb_iseq_t *iseq)
 {
+#if USE_LAZY_LOAD
     if (iseq->body == NULL) {
 	rb_iseq_complete((rb_iseq_t *)iseq);
     }
+#endif
     return iseq;
 }
-#else
-#define rb_iseq_check(iseq) iseq
-#endif
 
 enum ruby_special_exceptions {
     ruby_error_reenter,