| // run | |
| // Copyright 2016 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. | |
| // Make sure we don't start marshaling (writing to the stack) | |
| // arguments until those arguments are evaluated and known | |
| // not to unconditionally panic. If they unconditionally panic, | |
| // we write some args but never do the call. That messes up | |
| // the logic which decides how big the argout section needs to be. | |
| package main | |
| type W interface { | |
| Write([]byte) | |
| } | |
| type F func(W) | |
| func foo(f F) { | |
| defer func() { | |
| if r := recover(); r != nil { | |
| usestack(1000) | |
| } | |
| }() | |
| f(nil) | |
| } | |
| func main() { | |
| foo(func(w W) { | |
| var x []string | |
| w.Write([]byte(x[5])) | |
| }) | |
| } | |
| func usestack(n int) { | |
| if n == 0 { | |
| return | |
| } | |
| usestack(n - 1) | |
| } |