* enum.c (enum_first): should check negative length.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@23623 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,7 @@
+Wed Jun  3 09:03:23 2009  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* enum.c (enum_first): should check negative length.
+
 Tue Jun  2 17:32:40 2009  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* enum.c (first_i): Enumerator#first should consume only what is

enum.c

@@ -654,6 +654,9 @@ enum_first(int argc, VALUE *argv, VALUE obj)
 	rb_scan_args(argc, argv, "01", &n);
 	len = NUM2LONG(n);
 	if (len == 0) return rb_ary_new2(0);
+	if (len < 0) {
+	    rb_raise(rb_eArgError, "negative length");
+	}
 	ary[0] = len;
 	ary[1] = rb_ary_new2(len);
     }