unreachable.hpp

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//    OpenVPN -- An application to securely tunnel IP networks
//               over a single port, with support for SSL/TLS-based
//               session authentication and key exchange,
//               packet encryption, packet authentication, and
//               packet compression.
//
//    Copyright (C) 2024- OpenVPN Inc.
//
//    SPDX-License-Identifier: MPL-2.0 OR AGPL-3.0-only WITH openvpn3-openssl-exception
//
 
 
#pragma once
 
namespace openvpn {
 
// Replace std::unreachable, only available in C++23
// Based on https://en.cppreference.com/w/cpp/utility/unreachable
[[noreturn]] inline void unreachable()
{
    // Uses compiler specific extensions if possible.
    // Even if no extension is used, undefined behavior is still raised by
    // an empty function body and the noreturn attribute.
#if defined(__GNUC__)
    __builtin_unreachable();
#elif defined(_MSC_VER)
    __assume(false);
#endif
}
 
} // namespace openvpn