blob: b137071e4fdb85b12c8d12656b6522b123216545 [file] [log] [blame]
// run
// Copyright 2021 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.
// This tickles a stack-allocation bug when the register ABI is enabled.
// The original report was from cue, internal/core/adt/equality.go,
// function equalVertex.
// In the failing case, something bad gets passed to equalTerminal.
package main
import "fmt"
type Kind uint16
type Flag uint16
const (
allKinds Kind = 1
TopKind Kind = (allKinds - 1)
)
type Value interface {
Kind() Kind
}
type Vertex struct {
BaseValue Value
name string
}
func (v *Vertex) Kind() Kind {
return TopKind
}
func main() {
vA := &Vertex{name:"vA",}
vB := &Vertex{name:"vB",}
vX := &Vertex{name:"vX",}
vA.BaseValue = vX
vB.BaseValue = vX
_ = equalVertex(vA, vB, Flag(1))
}
var foo string
//go:noinline
func (v *Vertex) IsClosedStruct() bool {
return true
}
func equalVertex(x *Vertex, v Value, flags Flag) bool {
y, ok := v.(*Vertex)
if !ok {
return false
}
v, ok1 := x.BaseValue.(Value)
w, ok2 := y.BaseValue.(Value)
if !ok1 && !ok2 {
return true // both are struct or list.
}
return equalTerminal(v, w, flags)
}
//go:noinline
func equalTerminal(x Value, y Value, flags Flag) bool {
foo = fmt.Sprintf("EQclosed %s %s %d\n", x.(*Vertex).name, y.(*Vertex).name, flags)
return true
}