Introduce the ANNOTATE_LEAKING_OBJECT_PTR annotation that can be used to mark

base/metrics/histogram.cc

 // Copyright (c) 2011 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.
 
 // Histogram is an object that aggregates statistics, and can summarize them in
 // various forms, including ASCII graphical, HTML, and numerically (as a
 // vector of numbers corresponding to each of the aggregating buckets).
 // See header file for details and examples.
 
 #include "base/metrics/histogram.h"
 
 #include <math.h>
 
 #include <algorithm>
 #include <string>
 
+#include "base/debug/leak_annotations.h"
 #include "base/logging.h"
 #include "base/pickle.h"
 #include "base/stringprintf.h"
 #include "base/synchronization/lock.h"
 
 namespace base {
 
 // Static table of checksums for all possible 8 bit bytes.
 const uint32 Histogram::kCrcTable[256] = {0x0, 0x77073096L, 0xee0e612cL,
 0x990951baL, 0x76dc419L, 0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0xedb8832L,
@@ skipping 67 matching lines @@
     Histogram* tentative_histogram =
         new Histogram(name, minimum, maximum, bucket_count);
     tentative_histogram->InitializeBucketRange();
     tentative_histogram->SetFlags(flags);
     histogram =
         StatisticsRecorder::RegisterOrDeleteDuplicate(tentative_histogram);
   }
 
   DCHECK_EQ(HISTOGRAM, histogram->histogram_type());
   DCHECK(histogram->HasConstructorArguments(minimum, maximum, bucket_count));
+  ANNOTATE_LEAKING_OBJECT_PTR(histogram);  // see crbug.com/79322

[jar (doing other things), 2011/04/15 15:53:37]

There are actually 3 distinct FactoryGet routines in this file (each handling a
slightly different set of argument lists).  Each has this same pattern, and each
should probably be annotated this way.  

I tried to find a way to factor out the common code patterns (I hate
replication), but did not see a clean and readable way... but if you see a
way... great.

[Alexander Potapenko, 2011/04/18 09:45:13]

There are actually four of them, as I can see:

Histogram::FactoryGet
BooleanHistogram::FactoryGet
LinearHistogram::FactoryGet
CustomHistogram::FactoryGet

I've annotated all of them -- is that ok?

   return histogram;
 }
 
 Histogram* Histogram::FactoryTimeGet(const std::string& name,
                                      TimeDelta minimum,
                                      TimeDelta maximum,
                                      size_t bucket_count,
                                      Flags flags) {
   return FactoryGet(name, minimum.InMilliseconds(), maximum.InMilliseconds(),
                     bucket_count, flags);
@@ skipping 1008 matching lines @@
 }
 
 // static
 StatisticsRecorder::HistogramMap* StatisticsRecorder::histograms_ = NULL;
 // static
 base::Lock* StatisticsRecorder::lock_ = NULL;
 // static
 bool StatisticsRecorder::dump_on_exit_ = false;
 
 }  // namespace base