|  | // run | 
|  |  | 
|  | // Copyright 2013 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 "runtime" | 
|  |  | 
|  | type Closer interface { | 
|  | Close() | 
|  | } | 
|  |  | 
|  | func nilInterfaceDeferCall() { | 
|  | defer func() { | 
|  | // make sure a traceback happens with jmpdefer on the stack | 
|  | runtime.GC() | 
|  | }() | 
|  | var x Closer | 
|  | defer x.Close() | 
|  | } | 
|  |  | 
|  | func shouldPanic(f func()) { | 
|  | defer func() { | 
|  | if recover() == nil { | 
|  | panic("did not panic") | 
|  | } | 
|  | }() | 
|  | f() | 
|  | } | 
|  |  | 
|  | func main() { | 
|  | shouldPanic(nilInterfaceDeferCall) | 
|  | } |