go/test/fixedbugs/issue19743.go

32 строки
669 B
Go

// errorcheck -0 -m -l
// 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 foo
// Escape analysis needs to treat the uintptr-typed reflect.*Header fields as pointers.
import (
"reflect"
"unsafe"
)
type immutableBytes []byte
// Bug was failure to leak param b.
func toString(b immutableBytes) string { // ERROR "leaking param: b$"
var s string
if len(b) == 0 {
return s
}
strHeader := (*reflect.StringHeader)(unsafe.Pointer(&s))
strHeader.Data = (*reflect.SliceHeader)(unsafe.Pointer(&b)).Data
l := len(b)
strHeader.Len = l
return s
}