golang b 代码
文件路径：/test/fixedbugs/bug510.dir/b.go
/ Copyright 2020 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.
package main
import "./a"
func main() {
_, ok := a.F().(*map[int]bool)
if !ok {
panic("bad type")
}
}