golang/test/fixedbugs/issue67255.go

34 lines
922 B
Go

// run
// Copyright 2024 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
var zero int
var sink any
func main() {
var objs [][]*byte
for i := 10; i < 200; i++ {
// The objects we're allocating here are pointer-ful. Some will
// max out their size class, which are the ones we want.
// We also allocate from small to large, so that the object which
// maxes out its size class is the last one allocated in that class.
// This allocation pattern leaves the next object in the class
// unallocated, which we need to reproduce the bug.
objs = append(objs, make([]*byte, i))
}
sink = objs // force heap allocation
// Bug will happen as soon as the write barrier turns on.
for range 10000 {
sink = make([]*byte, 1024)
for _, s := range objs {
s = append(s, make([]*byte, zero)...)
}
}
}