Undefined symbols for architecture x86_64:
  "_VTDecompressionSessionCreate", referenced from:
      AgoraRTC::H264VideoToolboxDecoder::ResetDecompressionSession() in AgoraRtcEngineKit(libAgoraRTCEngine.a-x86_64-master.o)
      
"_kVTDecompressionPropertyKey_RealTime", referenced from:
      AgoraRTC::H264VideoToolboxDecoder::ResetDecompressionSession() in AgoraRtcEngineKit(libAgoraRTCEngine.a-x86_64-master.o)
      AgoraRTC::H264VideoToolboxDecoder::ConfigureDecompressionSession() in AgoraRtcEngineKit(libAgoraRTCEngine.a-x86_64-master.o)
     
"_VTDecompressionSessionDecodeFrame", referenced from:
      AgoraRTC::H264VideoToolboxDecoder::Decode(AgoraRTC::EncodedImage const&, bool, AgoraRTC::RTPFragmentationHeader const*, AgoraRTC::CodecSpecificInfo const*, long long) in AgoraRtcEngineKit(libAgoraRTCEngine.a-x86_64-master.o)

我在工程中導入融雲後,出現這種錯誤.基本上都按照文檔的上要求都進行編譯了.出現這種錯誤是為什麼?