base/deprecation.h

/*
 *  Copyright (c) 2015 The WebRTC 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 in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#ifndef WEBRTC_BASE_DEPRECATION_H_
#define WEBRTC_BASE_DEPRECATION_H_

// Annotate the declarations of deprecated functions with this to cause a
// compiler warning when they're used. Like so:
//
//   RTC_DEPRECATED std::pony PonyPlz(const std::pony_spec& ps);
//
// NOTE 1: The annotation goes on the declaration in the .h file, not the
// definition in the .cc file!
//
// NOTE 2: In order to keep unit testing the deprecated function without
// getting warnings, do something like this:
//
//   std::pony DEPRECATED_PonyPlz(const std::pony_spec& ps);
//   RTC_DEPRECATED inline std::pony PonyPlz(const std::pony_spec& ps) {
//     return DEPRECATED_PonyPlz(ps);
//   }
//
// In other words, rename the existing function, and provide an inline wrapper
// using the original name that calls it. That way, callers who are willing to
// call it using the DEPRECATED_-prefixed name don't get the warning.
//
// TODO(kwiberg): Remove this when we can use [[deprecated]] from C++14.
#if defined(_MSC_VER)
// Note: Deprecation warnings seem to fail to trigger on Windows
// (https://bugs.chromium.org/p/webrtc/issues/detail?id=5368).
#define RTC_DEPRECATED __declspec(deprecated)
#elif defined(__GNUC__)
#define RTC_DEPRECATED __attribute__ ((__deprecated__))
#else
#define RTC_DEPRECATED
#endif

#endif  // WEBRTC_BASE_DEPRECATION_H_