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// run
// Copyright 2020 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 (
"unsafe"
)
//go:notinheap
type S struct{ x int }
func main() {
var i int
p := (*S)(unsafe.Pointer(uintptr(unsafe.Pointer(&i))))
v := uintptr(unsafe.Pointer(p))
// p is a pointer to a go:notinheap type. Like some C libraries,
// we stored an integer in that pointer. That integer just happens
// to be the address of i.
// v is also the address of i.
// p has a base type which is marked go:notinheap, so it
// should not be adjusted when the stack is copied.
recurse(100, p, v)
}
func recurse(n int, p *S, v uintptr) {
if n > 0 {
recurse(n-1, p, v)
}
if uintptr(unsafe.Pointer(p)) != v {
panic("adjusted notinheap pointer")
}
}
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