mirror of
https://github.com/golang/go
synced 2024-11-18 03:34:42 -07:00
54f9c0416a
Nil check is special in that it has no use but we must keep it. Count it as a use of the auto. Fixes #27278. Change-Id: I857c3d0db2ebdca1bc342b4993c0dac5c01e067f Reviewed-on: https://go-review.googlesource.com/131955 Run-TryBot: Cherry Zhang <cherryyz@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
64 lines
865 B
Go
64 lines
865 B
Go
// run
|
|
|
|
// 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.
|
|
|
|
// Issue 27278: dead auto elim deletes an auto and its
|
|
// initialization, but it is live because of a nil check.
|
|
|
|
package main
|
|
|
|
type T struct {
|
|
_ [3]string
|
|
T2
|
|
}
|
|
|
|
func (t *T) M() []string {
|
|
return t.T2.M()
|
|
}
|
|
|
|
type T2 struct {
|
|
T3
|
|
}
|
|
|
|
func (t *T2) M() []string {
|
|
return t.T3.M()
|
|
}
|
|
|
|
type T3 struct {
|
|
a string
|
|
}
|
|
|
|
func (t *T3) M() []string {
|
|
return []string{}
|
|
}
|
|
|
|
func main() {
|
|
poison()
|
|
f()
|
|
}
|
|
|
|
//go:noinline
|
|
func f() {
|
|
(&T{}).M()
|
|
grow(10000)
|
|
}
|
|
|
|
// grow stack, triggers stack copy
|
|
func grow(n int) {
|
|
if n == 0 {
|
|
return
|
|
}
|
|
grow(n-1)
|
|
}
|
|
|
|
// put some junk on stack, which cannot be valid address
|
|
//go:noinline
|
|
func poison() {
|
|
x := [10]int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}
|
|
g = x
|
|
}
|
|
|
|
var g [10]int
|