go/test/fixedbugs/issue25516.go
Keith Randall db9341a024 cmd/compile: update WBLoads during deadcode
When we deadcode-remove a block which is a write barrier test,
remove that block from the list of write barrier test blocks.

Fixes #25516

Change-Id: I1efe732d5476003eab4ad6bf67d0340d7874ff0c
Reviewed-on: https://go-review.googlesource.com/115037
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-05-29 17:45:36 +00:00

27 lines
558 B
Go

// compile
// Copyright 2018 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 dead write barriers are handled correctly.
package main
func f(p **int) {
// The trick here is to eliminate the block containing the write barrier,
// but only after the write barrier branches are inserted.
// This requires some delicate code.
i := 0
var b []bool
var s string
for true {
if b[i] {
var a []string
s = a[len(s)]
i = 0
}
*p = nil
}
}