C++11 declares a type safe null pointer

content/common/gpu/media/h264_dpb.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/stl_util.h"
 #include "content/common/gpu/media/h264_dpb.h"
 
@@ skipping 54 matching lines @@
 }
 
 H264Picture* H264DPB::GetShortRefPicByPicNum(int pic_num) {
   for (size_t i = 0; i < pics_.size(); ++i) {
     H264Picture* pic = pics_[i];
     if (pic->ref && !pic->long_term && pic->pic_num == pic_num)
       return pic;
   }
 
   DVLOG(1) << "Missing short ref pic num: " << pic_num;
-  return NULL;
+  return nullptr;
 }
 
 H264Picture* H264DPB::GetLongRefPicByLongTermPicNum(int pic_num) {
   for (size_t i = 0; i < pics_.size(); ++i) {
     H264Picture* pic = pics_[i];
     if (pic->ref && pic->long_term && pic->long_term_pic_num == pic_num)
       return pic;
   }
 
   DVLOG(1) << "Missing long term pic num: " << pic_num;
-  return NULL;
+  return nullptr;
 }
 
 H264Picture* H264DPB::GetLowestFrameNumWrapShortRefPic() {
-  H264Picture* ret = NULL;
+  H264Picture* ret = nullptr;
   for (size_t i = 0; i < pics_.size(); ++i) {
     H264Picture* pic = pics_[i];
     if (pic->ref && !pic->long_term &&
         (!ret || pic->frame_num_wrap < ret->frame_num_wrap))
       ret = pic;
   }
   return ret;
 }
 
 void H264DPB::GetNotOutputtedPicsAppending(H264Picture::PtrVector& out) {
@@ skipping 14 matching lines @@
 
 void H264DPB::GetLongTermRefPicsAppending(H264Picture::PtrVector& out) {
   for (size_t i = 0; i < pics_.size(); ++i) {
     H264Picture* pic = pics_[i];
     if (pic->ref && pic->long_term)
       out.push_back(pic);
   }
 }
 
 }  // namespace content