From 338602596cab95d90137409ab1d9ca462c859156 Mon Sep 17 00:00:00 2001
From: terelius <terelius@webrtc.org>
Date: Fri, 12 May 2017 23:37:18 -0700
Subject: [PATCH] Initialize PeerConnection members in declaration order and
 destroy them in reverse order.

BUG=webrtc:7658

Review-Url: https://codereview.webrtc.org/2882803002
Cr-Commit-Position: refs/heads/master@{#18130}
---
 webrtc/pc/peerconnection.cc |  6 ++++--
 webrtc/pc/peerconnection.h  | 15 +++++++++------
 2 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/webrtc/pc/peerconnection.cc b/webrtc/pc/peerconnection.cc
index 65203fdc73..852dd39de5 100644
--- a/webrtc/pc/peerconnection.cc
+++ b/webrtc/pc/peerconnection.cc
@@ -395,10 +395,10 @@ PeerConnection::PeerConnection(PeerConnectionFactory* factory)
     : factory_(factory),
       observer_(NULL),
       uma_observer_(NULL),
+      event_log_(RtcEventLog::Create()),
       signaling_state_(kStable),
       ice_connection_state_(kIceConnectionNew),
       ice_gathering_state_(kIceGatheringNew),
-      event_log_(RtcEventLog::Create()),
       rtcp_cname_(GenerateRtcpCname()),
       local_streams_(StreamCollection::Create()),
       remote_streams_(StreamCollection::Create()) {}
@@ -1289,7 +1289,6 @@ void PeerConnection::Close() {
   stats_->UpdateStats(kStatsOutputLevelStandard);
 
   session_->Close();
-  event_log_.reset();
   network_thread()->Invoke<void>(
       RTC_FROM_HERE,
       rtc::Bind(&cricket::PortAllocator::DiscardCandidatePool,
@@ -1297,6 +1296,9 @@ void PeerConnection::Close() {
 
   factory_->worker_thread()->Invoke<void>(RTC_FROM_HERE,
                                           [this] { call_.reset(); });
+
+  // The event log must outlive call (and any other object that uses it).
+  event_log_.reset();
 }
 
 void PeerConnection::OnSessionStateChange(WebRtcSession* /*session*/,
diff --git a/webrtc/pc/peerconnection.h b/webrtc/pc/peerconnection.h
index 23e7e8e58b..1e2ca3bb95 100644
--- a/webrtc/pc/peerconnection.h
+++ b/webrtc/pc/peerconnection.h
@@ -402,14 +402,16 @@ class PeerConnection : public PeerConnectionInterface,
   rtc::scoped_refptr<PeerConnectionFactory> factory_;
   PeerConnectionObserver* observer_;
   UMAObserver* uma_observer_;
+
+  // The EventLog needs to outlive |call_| (and any other object that uses it).
+  std::unique_ptr<RtcEventLog> event_log_;
+
   SignalingState signaling_state_;
   IceConnectionState ice_connection_state_;
   IceGatheringState ice_gathering_state_;
   PeerConnectionInterface::RTCConfiguration configuration_;
 
   std::unique_ptr<cricket::PortAllocator> port_allocator_;
-  // The EventLog needs to outlive |call_|.
-  std::unique_ptr<RtcEventLog> event_log_;
 
   // One PeerConnection has only one RTCP CNAME.
   // https://tools.ietf.org/html/draft-ietf-rtcweb-rtp-usage-26#section-4.9
@@ -436,15 +438,16 @@ class PeerConnection : public PeerConnectionInterface,
 
   bool remote_peer_supports_msid_ = false;
 
+  std::unique_ptr<Call> call_;
+  std::unique_ptr<WebRtcSession> session_;
+  std::unique_ptr<StatsCollector> stats_;  // A pointer is passed to senders_
+  rtc::scoped_refptr<RTCStatsCollector> stats_collector_;
+
   std::vector<rtc::scoped_refptr<RtpSenderProxyWithInternal<RtpSenderInternal>>>
       senders_;
   std::vector<
       rtc::scoped_refptr<RtpReceiverProxyWithInternal<RtpReceiverInternal>>>
       receivers_;
-  std::unique_ptr<WebRtcSession> session_;
-  std::unique_ptr<Call> call_;
-  std::unique_ptr<StatsCollector> stats_;
-  rtc::scoped_refptr<RTCStatsCollector> stats_collector_;
 };
 
 }  // namespace webrtc