go issue27695c 源码

  • 2022-07-15
  • 浏览 (827)

golang issue27695c 代码

文件路径:/test/fixedbugs/issue27695c.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.

// Make sure return values aren't scanned until they
// are initialized, when calling functions and methods
// via reflect.

package main

import (
	"io"
	"reflect"
	"runtime"
	"unsafe"
)

var badPtr uintptr

var sink []byte

func init() {
	// Allocate large enough to use largeAlloc.
	b := make([]byte, 1<<16-1)
	sink = b // force heap allocation
	//  Any space between the object and the end of page is invalid to point to.
	badPtr = uintptr(unsafe.Pointer(&b[len(b)-1])) + 1
}

func f(d func(error) error) error {
	// Initialize callee args section with a bad pointer.
	g(badPtr, badPtr, badPtr, badPtr)

	// Then call a function which returns a pointer.
	// That return slot starts out holding a bad pointer.
	return d(io.EOF)
}

//go:noinline
func g(x, y, z, w uintptr) {
}

type T struct {
}

func (t *T) Foo(e error) error {
	runtime.GC()
	return e
}

func main() {
	// Functions
	d := reflect.MakeFunc(reflect.TypeOf(func(e error) error { return e }),
		func(args []reflect.Value) []reflect.Value {
			runtime.GC()
			return args
		}).Interface().(func(error) error)
	f(d)

	// Methods
	x := reflect.ValueOf(&T{}).Method(0).Interface().(func(error) error)
	f(x)
}

相关信息

go 源码目录

相关文章

go bug000 源码

go bug002 源码

go bug003 源码

go bug004 源码

go bug005 源码

go bug006 源码

go bug007 源码

go bug008 源码

go bug009 源码

go bug010 源码

0  赞