首页
学习
活动
专区
圈层
工具
发布
社区首页 >问答首页 >发布模式下的Dartium构建错误

发布模式下的Dartium构建错误
EN

Stack Overflow用户
提问于 2012-01-11 12:03:47
回答 1查看 167关注 0票数 1

我正在跟踪http://code.google.com/p/dart/wiki/BuildingDartium#Build,并尝试在Release模式下构建dartium,但遇到以下错误:

代码语言:javascript
复制
$ ./dartium_tools/build.py --mode=Release
.
.
.
  CXX(target) out/Release/obj.target/webrtc_video_coding/third_party/webrtc/modules/video_coding/main/source/rtt_filter.o
  CXX(target) out/Release/obj.target/webrtc_video_coding/third_party/webrtc/modules/video_coding/main/source/session_info.o
  CXX(target) out/Release/obj.target/webrtc_video_coding/third_party/webrtc/modules/video_coding/main/source/timestamp_extrapolator.o
third_party/webrtc/modules/video_coding/main/source/session_info.cc: In member function ‘int webrtc::VCMSessionInfo::PrepareForDecode(uint8_t*)’:
third_party/webrtc/modules/video_coding/main/source/session_info.cc:590:8: error: variable ‘previous_lost’ set but not used [-Werror=unused-but-set-variable]
cc1plus: all warnings being treated as errors

make: *** [out/Release/obj.target/webrtc_video_coding/third_party/webrtc/modules/video_coding/main/source/session_info.o] Error 1
make: *** Waiting for unfinished jobs....
Traceback (most recent call last):
  File "./dartium_tools/build.py", line 67, in <module>
    main()
  File "./dartium_tools/build.py", line 64, in main
    [target for (target, _) in targets])
  File "/home/sangeeth/work/g/dartium/src/dartium_tools/utils.py", line 97, in runCommand
    raise Exception('Failed to run command. return code=%s' % p.returncode)
Exception: Failed to run command. return code=2
$ 

但当我查看代码dartium/src/third_party/webrtc/modules/video_coding/main/source/session_info.cc::VCMSessionInfo::PrepareForDecode()时,我看到了以下内容:

代码语言:javascript
复制
int VCMSessionInfo::PrepareForDecode(uint8_t* frame_buffer) {
  int length = SessionLength();
  int real_data_bytes = 0;
  if (length == 0)
      return length;
  bool previous_lost = false;
  PacketIterator it = packets_.begin();
  PacketIterator prev_it = it;
  for (; it != packets_.end(); ++it) {
    bool packet_loss = ((*prev_it).sizeBytes == 0 ||
        !InSequence(it, prev_it));
    if ((*it).bits) {
      if (prev_it != it) {  // Not the first packet.
        uint8_t* ptr_first_byte =
            const_cast<uint8_t*>((*it).dataPtr);

        if (packet_loss) {
          // It is be better to throw away this packet if we are
          // missing the previous packet.
          memset(ptr_first_byte, 0, (*it).sizeBytes);
          previous_lost = true;
          ++packets_not_decodable_;
        } else if ((*it).sizeBytes > 0) {
          // Glue with previous byte.
          // Move everything from [this packet start + 1, end of buffer] one
          // byte to the left.
          uint8_t* ptr_prev_byte =
              const_cast<uint8_t*>((*prev_it).dataPtr) +
              (*prev_it).sizeBytes - 1;
          *ptr_prev_byte = (*ptr_prev_byte) | (*ptr_first_byte);
          memmove(const_cast<uint8_t*>((*it).dataPtr),
                  (*it).dataPtr + 1, (*it).sizeBytes - 1);
          ShiftSubsequentPackets(it, -1);
          (*it).sizeBytes--;
          length--;
          previous_lost = false;
          real_data_bytes += (*it).sizeBytes;
        }
      } else {

        memset(const_cast<uint8_t*>((*it).dataPtr), 0,
               (*it).sizeBytes);
        previous_lost = true;
        ++packets_not_decodable_;
      }
    } else if (packet_loss &&
      (*it).codecSpecificHeader.codec == kRTPVideoH263) {
      // Pad H.263 packet losses with 10 zeros to make it easier
      // for the decoder.
      const int kPaddingLength = 10;
      WebRtc_UWord8 padding_data[kPaddingLength] = {0};
      // Make a copy of the previous packet.
      VCMPacket padding_packet(*it);
      ++padding_packet.seqNum;
      padding_packet.dataPtr = padding_data;
      padding_packet.sizeBytes = kPaddingLength;
      length += InsertPacket(padding_packet, frame_buffer, false, 0);
      previous_lost = true;
    } else {
      real_data_bytes += (*it).sizeBytes;
      previous_lost = false;
    }
    prev_it = it;
  }
  if (real_data_bytes == 0) {
    // Drop the frame since all it contains are zeros.
    for (it = packets_.begin(); it != packets_.end(); ++it)
      (*it).sizeBytes = 0;
    length = 0;
  }
  return length;
}

在许多地方已经使用了bool变量previous_lost (设置为falsetrue)。

任何关于如何进行这项工作的有价值的意见都将是一个很大的帮助。

EN

回答 1

Stack Overflow用户

回答已采纳

发布于 2012-01-11 12:18:59

如果您稍后不读取值,那么将bool设置为truefalse是没有意义的-在您发布的代码中,previous_lost的值实际上是在几个地方设置的,但没有任何地方设置了用于执行任何操作的值(例如if (previous_lost) ... )。这就是上下文中“已使用”的含义:如果变量的值被读取,则使用该变量。

请注意,这(通常)适用于任何类型的变量:如果我将int设置为42,并且在以后的计算中不使用它,那么它也不会被“使用”。

在这些情况下,变量是完全多余的-它没有做任何有用的事情,因为它不被其他代码使用。通常,这类警告意味着可能应该使用previous_lost的代码被意外省略(或被删除),需要进行说明。或者,变量可能只是多余的,可以完全删除。

票数 1
EN
页面原文内容由Stack Overflow提供。腾讯云小微IT领域专用引擎提供翻译支持
原文链接:

https://stackoverflow.com/questions/8813986

复制
相关文章

相似问题

领券
问题归档专栏文章快讯文章归档关键词归档开发者手册归档开发者手册 Section 归档