| // Copyright 2021 the V8 project authors. All rights reserved. | |
| // Use of this source code is governed by a BSD-style license that can be | |
| // found in the LICENSE file. | |
| namespace cppgc { | |
| namespace internal { | |
| // Special tag type used to denote some sentinel member. The semantics of the | |
| // sentinel is defined by the embedder. | |
| struct SentinelPointer { | |
| static constexpr intptr_t kSentinelValue = 0b10; | |
| template <typename T> | |
| operator T*() const { | |
| return reinterpret_cast<T*>(kSentinelValue); | |
| } | |
| // Hidden friends. | |
| friend bool operator==(SentinelPointer, SentinelPointer) { return true; } | |
| friend bool operator!=(SentinelPointer, SentinelPointer) { return false; } | |
| }; | |
| } // namespace internal | |
| constexpr internal::SentinelPointer kSentinelPointer; | |
| } // namespace cppgc | |