patch reflect: Zero/Len

internal/lib/reflect/unsafeheader.go

@@ -0,0 +1,37 @@
+// 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 unsafeheader contains header declarations for the Go runtime's slice
+// and string implementations.
+//
+// This package allows packages that cannot import "reflect" to use types that
+// are tested to be equivalent to reflect.SliceHeader and reflect.StringHeader.
+package reflect
+
+import (
+	"unsafe"
+)
+
+// unsafeheaderSlice is the runtime representation of a slice.
+// It cannot be used safely or portably and its representation may
+// change in a later release.
+//
+// Unlike reflect.SliceHeader, its Data field is sufficient to guarantee the
+// data it references will not be garbage collected.
+type unsafeheaderSlice struct {
+	Data unsafe.Pointer
+	Len  int
+	Cap  int
+}
+
+// unsafeheaderString is the runtime representation of a string.
+// It cannot be used safely or portably and its representation may
+// change in a later release.
+//
+// Unlike reflect.StringHeader, its Data field is sufficient to guarantee the
+// data it references will not be garbage collected.
+type unsafeheaderString struct {
+	Data unsafe.Pointer
+	Len  int
+}