mirror of
https://github.com/golang/go
synced 2024-11-23 13:20:09 -07:00
53fd522c0d
Follows suit with https://go-review.googlesource.com/#/c/20111. Generated by running $ grep -R 'Go Authors. All' * | cut -d":" -f1 | while read F;do perl -pi -e 's/Go Authors. All/Go Authors. All/g' $F;done The code in cmd/internal/unvendor wasn't changed. Fixes #15213 Change-Id: I4f235cee0a62ec435f9e8540a1ec08ae03b1a75f Reviewed-on: https://go-review.googlesource.com/21819 Reviewed-by: Ian Lance Taylor <iant@golang.org> Run-TryBot: Ian Lance Taylor <iant@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>
108 lines
2.0 KiB
Go
108 lines
2.0 KiB
Go
// run
|
|
|
|
// Copyright 2014 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 8048. Incorrect handling of liveness when walking stack
|
|
// containing faulting frame.
|
|
|
|
package main
|
|
|
|
import "runtime"
|
|
|
|
func main() {
|
|
test1()
|
|
test2()
|
|
test3()
|
|
}
|
|
|
|
func test1() {
|
|
// test1f will panic without its own defer.
|
|
// The runtime.GC checks that we can walk the stack
|
|
// at that point and not get confused.
|
|
// The recover lets test1 exit normally.
|
|
defer func() {
|
|
runtime.GC()
|
|
recover()
|
|
}()
|
|
test1f()
|
|
}
|
|
|
|
func test1f() {
|
|
// Because b == false, the if does not execute,
|
|
// so x == nil, so the println(*x) faults reading
|
|
// from nil. The compiler will lay out the code
|
|
// so that the if body occurs above the *x,
|
|
// so if the liveness info at the *x is used, it will
|
|
// find the liveness at the call to runtime.GC.
|
|
// It will think y is live, but y is uninitialized,
|
|
// and the runtime will crash detecting a bad slice.
|
|
// The runtime should see that there are no defers
|
|
// corresponding to this panicked frame and ignore
|
|
// the frame entirely.
|
|
var x *int
|
|
var b bool
|
|
if b {
|
|
y := make([]int, 1)
|
|
runtime.GC()
|
|
x = &y[0]
|
|
}
|
|
println(*x)
|
|
}
|
|
|
|
func test2() {
|
|
// Same as test1, but the fault happens in the function with the defer.
|
|
// The runtime should see the defer and garbage collect the frame
|
|
// as if the PC were immediately after the defer statement.
|
|
defer func() {
|
|
runtime.GC()
|
|
recover()
|
|
}()
|
|
var x *int
|
|
var b bool
|
|
if b {
|
|
y := make([]int, 1)
|
|
runtime.GC()
|
|
x = &y[0]
|
|
}
|
|
println(*x)
|
|
}
|
|
|
|
func test3() {
|
|
// Like test1 but avoid array index, which does not
|
|
// move to end of function on ARM.
|
|
defer func() {
|
|
runtime.GC()
|
|
recover()
|
|
}()
|
|
test3setup()
|
|
test3f()
|
|
}
|
|
|
|
func test3setup() {
|
|
var x uintptr
|
|
var b bool
|
|
b = true
|
|
if b {
|
|
y := uintptr(123)
|
|
runtime.GC()
|
|
x = y
|
|
}
|
|
runtime.GC()
|
|
globl = x
|
|
}
|
|
|
|
var globl uintptr
|
|
|
|
func test3f() {
|
|
var x *int
|
|
var b bool
|
|
if b {
|
|
y := new(int)
|
|
runtime.GC()
|
|
x = y
|
|
}
|
|
println(*x)
|
|
}
|