go/test/fixedbugs/issue19168.go
Matthew Dempsky fe79c75268 [release-branch.go1.8] cmd/compile: add missing WBs for reflect.{Slice,String}Header.Data
Fixes #19168.

(*state).insertWBstore needed to be tweaked for backporting so that
store reflect.{Slice,String}Header.Data stores still fallthrough and
end the SSA block. This wasn't necessary at master because of CL
36834.

Change-Id: I3f4fcc0b189c53819ac29ef8de86fdad76a17488
Reviewed-on: https://go-review.googlesource.com/39615
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Austin Clements <austin@google.com>
2017-04-05 19:28:00 +00:00

59 lines
1.3 KiB
Go

// errorcheck -0 -l -d=wb
// Copyright 2017 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.
package p
import (
"reflect"
"unsafe"
reflect2 "reflect"
)
func sink(e interface{})
func a(hdr *reflect.SliceHeader, p *byte) {
hdr.Data = uintptr(unsafe.Pointer(p)) // ERROR "write barrier"
}
func b(hdr *reflect.StringHeader, p *byte) {
hdr.Data = uintptr(unsafe.Pointer(p)) // ERROR "write barrier"
}
func c(hdrs *[1]reflect.SliceHeader, p *byte) {
hdrs[0].Data = uintptr(unsafe.Pointer(p)) // ERROR "write barrier"
}
func d(hdr *struct{ s reflect.StringHeader }, p *byte) {
hdr.s.Data = uintptr(unsafe.Pointer(p)) // ERROR "write barrier"
}
func e(p *byte) (resHeap, resStack string) {
sink(&resHeap)
hdr := (*reflect.StringHeader)(unsafe.Pointer(&resHeap))
hdr.Data = uintptr(unsafe.Pointer(p)) // ERROR "write barrier"
// No write barrier for non-escaping stack vars.
hdr = (*reflect.StringHeader)(unsafe.Pointer(&resStack))
hdr.Data = uintptr(unsafe.Pointer(p))
return
}
func f(hdr *reflect2.SliceHeader, p *byte) {
hdr.Data = uintptr(unsafe.Pointer(p)) // ERROR "write barrier"
}
type SliceHeader struct {
Data uintptr
}
func g(hdr *SliceHeader, p *byte) {
// No write barrier for lookalike SliceHeader.
hdr.Data = uintptr(unsafe.Pointer(p))
}