golang issue4252 代码
文件路径：/test/fixedbugs/issue4252.go
/ rundir
/ Copyright 2012 The Go Authors. All rights reserved.
/ Use of this source code is governed by a BSD-style
/ license that can be found in the LICENSE file.
/ Issue 4252: tests that fixing the issue still allow
/ builtins to be redeclared and are not corrupted
/ in export data.
package ignored