// 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 }