From 109be507377fe7f6e8819ac94041d3fdcdf6fd2f Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 15:18:25 +0200 Subject: Adding upstream version 1.19.8. Signed-off-by: Daniel Baumann --- test/fixedbugs/issue52612.go | 49 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 test/fixedbugs/issue52612.go (limited to 'test/fixedbugs/issue52612.go') diff --git a/test/fixedbugs/issue52612.go b/test/fixedbugs/issue52612.go new file mode 100644 index 0000000..d8be049 --- /dev/null +++ b/test/fixedbugs/issue52612.go @@ -0,0 +1,49 @@ +// run + +// Copyright 2022 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 main + +import ( + "sync/atomic" + "unsafe" +) + +var one interface{} = 1 + +type eface struct { + typ unsafe.Pointer + data unsafe.Pointer +} + +func f(c chan struct{}) { + var x atomic.Value + + go func() { + x.Swap(one) // writing using the old marker + }() + for i := 0; i < 100000; i++ { + v := x.Load() // reading using the new marker + + p := (*eface)(unsafe.Pointer(&v)).typ + if uintptr(p) == ^uintptr(0) { + // We read the old marker, which the new reader + // doesn't know is a case where it should retry + // instead of returning it. + panic("bad typ field") + } + } + c <- struct{}{} +} + +func main() { + c := make(chan struct{}, 10) + for i := 0; i < 10; i++ { + go f(c) + } + for i := 0; i < 10; i++ { + <-c + } +} -- cgit v1.2.3