diff --git a/string.c b/string.c
index 6a89343bef..55a304334b 100644
--- a/string.c
+++ b/string.c
@@ -9361,7 +9361,6 @@ rb_str_ord(VALUE s)
 static VALUE
 rb_str_sum(int argc, VALUE *argv, VALUE str)
 {
-    VALUE vbits;
     int bits = 16;
     char *ptr, *p, *pend;
     long len;