Enable UBSan float-cast-overflow warnings and fix existing ones

webrtc/media/base/rtpdataengine.cc

 /*
  *  Copyright (c) 2012 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.
  */
 
 #include "webrtc/media/base/rtpdataengine.h"
 
 #include "webrtc/media/base/codec.h"
 #include "webrtc/media/base/mediaconstants.h"
 #include "webrtc/media/base/rtputils.h"
 #include "webrtc/media/base/streamparams.h"
 #include "webrtc/rtc_base/copyonwritebuffer.h"
 #include "webrtc/rtc_base/helpers.h"
 #include "webrtc/rtc_base/logging.h"
 #include "webrtc/rtc_base/ratelimiter.h"
+#include "webrtc/rtc_base/sanitizer.h"
 #include "webrtc/rtc_base/stringutils.h"
 
 namespace cricket {
 
 // We want to avoid IP fragmentation.
 static const size_t kDataMaxRtpPacketLen = 1200U;
 // We reserve space after the RTP header for future wiggle room.
 static const unsigned char kReservedSpace[] = {
   0x00, 0x00, 0x00, 0x00
 };
@@ skipping 36 matching lines @@
 
 RtpDataMediaChannel::~RtpDataMediaChannel() {
   std::map<uint32_t, RtpClock*>::const_iterator iter;
   for (iter = rtp_clock_by_send_ssrc_.begin();
        iter != rtp_clock_by_send_ssrc_.end();
        ++iter) {
     delete iter->second;
   }
 }
 
-void RtpClock::Tick(double now, int* seq_num, uint32_t* timestamp) {
+void RTC_NO_SANITIZE("float-cast-overflow")  // bugs.webrtc.org/8204
+RtpClock::Tick(double now, int* seq_num, uint32_t* timestamp) {
   *seq_num = ++last_seq_num_;
   *timestamp = timestamp_offset_ + static_cast<uint32_t>(now * clockrate_);
+  // UBSan: 5.92374e+10 is outside the range of representable values of type
+  // 'unsigned int'
 }
 
 const DataCodec* FindUnknownCodec(const std::vector<DataCodec>& codecs) {
   DataCodec data_codec(kGoogleRtpDataCodecPlType, kGoogleRtpDataCodecName);
   std::vector<DataCodec>::const_iterator iter;
   for (iter = codecs.begin(); iter != codecs.end(); ++iter) {
     if (!iter->Matches(data_codec)) {
       return &(*iter);
     }
   }
@@ skipping 247 matching lines @@
     *result = SDR_SUCCESS;
   }
   return true;
 }
 
 rtc::DiffServCodePoint RtpDataMediaChannel::PreferredDscp() const {
   return rtc::DSCP_AF41;
 }
 
 }  // namespace cricket