1 files changed, 3 insertions, 2 deletions
diff --git a/iseq.c b/iseq.c
index 3030899d83..fd148dc1a2 100644
--- a/iseq.c
+++ b/iseq.c
@@ -1104,7 +1104,8 @@ cdhash_each(VALUE key, VALUE value, VALUE ary)
 static VALUE
 iseq_data_to_ary(rb_iseq_t *iseq)
 {
-    long i, ti;
+    long i;
+    size_t ti;
     unsigned int pos;
     unsigned int line = 0;
     VALUE *seq;
@@ -1315,7 +1316,7 @@ iseq_data_to_ary(rb_iseq_t *iseq)
 	    rb_ary_push(body, (VALUE)label);
 	}
 
-	if (iseq->line_info_table[ti].position == pos) {
+	if (iseq->line_info_size < ti && iseq->line_info_table[ti].position == pos) {
 	    line = iseq->line_info_table[ti].line_no;
 	    rb_ary_push(body, INT2FIX(line));
 	    ti++;