| /* |
| * Copyright (c) 2017 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_RTC_BASE_ANNOTATIONS_H_ |
| #define WEBRTC_RTC_BASE_ANNOTATIONS_H_ |
| |
| // Annotate a function indicating the caller must examine the return value. |
| // Use like: |
| // int foo() RTC_WARN_UNUSED_RESULT; |
| // To explicitly ignore a result, cast to void. |
| // TODO(kwiberg): Remove when we can use [[nodiscard]] from C++17. |
| #if defined(__clang__) |
| #define RTC_WARN_UNUSED_RESULT __attribute__((__warn_unused_result__)) |
| #elif defined(__GNUC__) |
| // gcc has a __warn_unused_result__ attribute, but you can't quiet it by |
| // casting to void, so we don't use it. |
| #define RTC_WARN_UNUSED_RESULT |
| #else |
| #define RTC_WARN_UNUSED_RESULT |
| #endif |
| |
| // Macro to be used for switch-case fallthrough (required for enabling |
| // -Wimplicit-fallthrough warning on Clang). |
| #if defined(__clang__) |
| #define RTC_FALLTHROUGH() [[clang::fallthrough]] |
| #else |
| #define RTC_FALLTHROUGH() do { } while (0) |
| #endif |
| |
| // Prevent the compiler from warning about an unused variable. For example: |
| // int result = DoSomething(); |
| // assert(result == 17); |
| // RTC_UNUSED(result); |
| // Note: In most cases it is better to remove the unused variable rather than |
| // suppressing the compiler warning. |
| #define RTC_UNUSED(x) static_cast<void>(x) |
| |
| #endif // WEBRTC_RTC_BASE_ANNOTATIONS_H_ |