diff --git a/src/debugallocation.cc b/src/debugallocation.cc
new file mode 100644
index 0000000..c170bc7
--- /dev/null
+++ b/src/debugallocation.cc
@@ -0,0 +1,1458 @@
+// -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*-
+// Copyright (c) 2000, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// ---
+// Author: Urs Holzle <opensource@google.com>
+
+#include "config.h"
+#include <errno.h>
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+#ifdef HAVE_INTTYPES_H
+#include <inttypes.h>
+#endif
+// We only need malloc.h for struct mallinfo.
+#ifdef HAVE_STRUCT_MALLINFO
+// Malloc can be in several places on older versions of OS X.
+# if defined(HAVE_MALLOC_H)
+# include <malloc.h>
+# elif defined(HAVE_MALLOC_MALLOC_H)
+# include <malloc/malloc.h>
+# elif defined(HAVE_SYS_MALLOC_H)
+# include <sys/malloc.h>
+# endif
+#endif
+#ifdef HAVE_PTHREAD
+#include <pthread.h>
+#endif
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+#ifdef HAVE_MMAP
+#include <sys/mman.h>
+#endif
+#include <sys/stat.h>
+#include <sys/types.h>
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#include <gperftools/malloc_extension.h>
+#include <gperftools/malloc_hook.h>
+#include <gperftools/stacktrace.h>
+#include "addressmap-inl.h"
+#include "base/commandlineflags.h"
+#include "base/googleinit.h"
+#include "base/logging.h"
+#include "base/spinlock.h"
+#include "malloc_hook-inl.h"
+#include "symbolize.h"
+
+// NOTE: due to #define below, tcmalloc.cc will omit tc_XXX
+// definitions. So that debug implementations can be defined
+// instead. We're going to use do_malloc, do_free and other do_XXX
+// functions that are defined in tcmalloc.cc for actual memory
+// management
+#define TCMALLOC_USING_DEBUGALLOCATION
+#include "tcmalloc.cc"
+
+// __THROW is defined in glibc systems.  It means, counter-intuitively,
+// "This function will never throw an exception."  It's an optional
+// optimization tool, but we may need to use it to match glibc prototypes.
+#ifndef __THROW    // I guess we're not on a glibc system
+# define __THROW   // __THROW is just an optimization, so ok to make it ""
+#endif
+
+// On systems (like freebsd) that don't define MAP_ANONYMOUS, use the old
+// form of the name instead.
+#ifndef MAP_ANONYMOUS
+# define MAP_ANONYMOUS MAP_ANON
+#endif
+
+// ========================================================================= //
+
+DEFINE_bool(malloctrace,
+            EnvToBool("TCMALLOC_TRACE", false),
+            "Enables memory (de)allocation tracing to /tmp/google.alloc.");
+#ifdef HAVE_MMAP
+DEFINE_bool(malloc_page_fence,
+            EnvToBool("TCMALLOC_PAGE_FENCE", false),
+            "Enables putting of memory allocations at page boundaries "
+            "with a guard page following the allocation (to catch buffer "
+            "overruns right when they happen).");
+DEFINE_bool(malloc_page_fence_never_reclaim,
+            EnvToBool("TCMALLOC_PAGE_FRANCE_NEVER_RECLAIM", false),
+            "Enables making the virtual address space inaccessible "
+            "upon a deallocation instead of returning it and reusing later.");
+#else
+DEFINE_bool(malloc_page_fence, false, "Not usable (requires mmap)");
+DEFINE_bool(malloc_page_fence_never_reclaim, false, "Not usable (required mmap)");
+#endif
+DEFINE_bool(malloc_reclaim_memory,
+            EnvToBool("TCMALLOC_RECLAIM_MEMORY", true),
+            "If set to false, we never return memory to malloc "
+            "when an object is deallocated. This ensures that all "
+            "heap object addresses are unique.");
+DEFINE_int32(max_free_queue_size,
+             EnvToInt("TCMALLOC_MAX_FREE_QUEUE_SIZE", 10*1024*1024),
+             "If greater than 0, keep freed blocks in a queue instead of "
+             "releasing them to the allocator immediately.  Release them when "
+             "the total size of all blocks in the queue would otherwise exceed "
+             "this limit.");
+
+DEFINE_bool(symbolize_stacktrace,
+            EnvToBool("TCMALLOC_SYMBOLIZE_STACKTRACE", true),
+            "Symbolize the stack trace when provided (on some error exits)");
+
+// If we are LD_PRELOAD-ed against a non-pthreads app, then
+// pthread_once won't be defined.  We declare it here, for that
+// case (with weak linkage) which will cause the non-definition to
+// resolve to NULL.  We can then check for NULL or not in Instance.
+extern "C" int pthread_once(pthread_once_t *, void (*)(void))
+    ATTRIBUTE_WEAK;
+
+// ========================================================================= //
+
+// A safe version of printf() that does not do any allocation and
+// uses very little stack space.
+static void TracePrintf(int fd, const char *fmt, ...)
+  __attribute__ ((__format__ (__printf__, 2, 3)));
+
+// Round "value" up to next "alignment" boundary.
+// Requires that "alignment" be a power of two.
+static intptr_t RoundUp(intptr_t value, intptr_t alignment) {
+  return (value + alignment - 1) & ~(alignment - 1);
+}
+
+// ========================================================================= //
+
+class MallocBlock;
+
+// A circular buffer to hold freed blocks of memory.  MallocBlock::Deallocate
+// (below) pushes blocks into this queue instead of returning them to the
+// underlying allocator immediately.  See MallocBlock::Deallocate for more
+// information.
+//
+// We can't use an STL class for this because we need to be careful not to
+// perform any heap de-allocations in any of the code in this class, since the
+// code in MallocBlock::Deallocate is not re-entrant.
+template <typename QueueEntry>
+class FreeQueue {
+ public:
+  FreeQueue() : q_front_(0), q_back_(0) {}
+
+  bool Full() {
+    return (q_front_ + 1) % kFreeQueueSize == q_back_;
+  }
+
+  void Push(const QueueEntry& block) {
+    q_[q_front_] = block;
+    q_front_ = (q_front_ + 1) % kFreeQueueSize;
+  }
+
+  QueueEntry Pop() {
+    RAW_CHECK(q_back_ != q_front_, "Queue is empty");
+    const QueueEntry& ret = q_[q_back_];
+    q_back_ = (q_back_ + 1) % kFreeQueueSize;
+    return ret;
+  }
+
+  size_t size() const {
+    return (q_front_ - q_back_ + kFreeQueueSize) % kFreeQueueSize;
+  }
+
+ private:
+  // Maximum number of blocks kept in the free queue before being freed.
+  static const int kFreeQueueSize = 1024;
+
+  QueueEntry q_[kFreeQueueSize];
+  int q_front_;
+  int q_back_;
+};
+
+struct MallocBlockQueueEntry {
+  MallocBlockQueueEntry() : block(NULL), size(0),
+                            num_deleter_pcs(0), deleter_threadid(0) {}
+  MallocBlockQueueEntry(MallocBlock* b, size_t s) : block(b), size(s) {
+    if (FLAGS_max_free_queue_size != 0 && b != NULL) {
+      // Adjust the number of frames to skip (4) if you change the
+      // location of this call.
+      num_deleter_pcs =
+          GetStackTrace(deleter_pcs,
+                        sizeof(deleter_pcs) / sizeof(deleter_pcs[0]),
+                        4);
+      deleter_threadid = pthread_self();
+    } else {
+      num_deleter_pcs = 0;
+      // Zero is an illegal pthread id by my reading of the pthread
+      // implementation:
+      deleter_threadid = 0;
+    }
+  }
+
+  MallocBlock* block;
+  size_t size;
+
+  // When deleted and put in the free queue, we (flag-controlled)
+  // record the stack so that if corruption is later found, we can
+  // print the deleter's stack.  (These three vars add 144 bytes of
+  // overhead under the LP64 data model.)
+  void* deleter_pcs[16];
+  int num_deleter_pcs;
+  pthread_t deleter_threadid;
+};
+
+class MallocBlock {
+ public:  // allocation type constants
+
+  // Different allocation types we distinguish.
+  // Note: The lower 4 bits are not random: we index kAllocName array
+  // by these values masked with kAllocTypeMask;
+  // the rest are "random" magic bits to help catch memory corruption.
+  static const int kMallocType = 0xEFCDAB90;
+  static const int kNewType = 0xFEBADC81;
+  static const int kArrayNewType = 0xBCEADF72;
+
+ private:  // constants
+
+  // A mask used on alloc types above to get to 0, 1, 2
+  static const int kAllocTypeMask = 0x3;
+  // An additional bit to set in AllocType constants
+  // to mark now deallocated regions.
+  static const int kDeallocatedTypeBit = 0x4;
+
+  // For better memory debugging, we initialize all storage to known
+  // values, and overwrite the storage when it's deallocated:
+  // Byte that fills uninitialized storage.
+  static const int kMagicUninitializedByte = 0xAB;
+  // Byte that fills deallocated storage.
+  // NOTE: tcmalloc.cc depends on the value of kMagicDeletedByte
+  //       to work around a bug in the pthread library.
+  static const int kMagicDeletedByte = 0xCD;
+  // A size_t (type of alloc_type_ below) in a deallocated storage
+  // filled with kMagicDeletedByte.
+  static const size_t kMagicDeletedSizeT =
+      0xCDCDCDCD | (((size_t)0xCDCDCDCD << 16) << 16);
+    // Initializer works for 32 and 64 bit size_ts;
+    // "<< 16 << 16" is to fool gcc from issuing a warning
+    // when size_ts are 32 bits.
+
+  // NOTE: on Linux, you can enable malloc debugging support in libc by
+  // setting the environment variable MALLOC_CHECK_ to 1 before you
+  // start the program (see man malloc).
+
+  // We use either do_malloc or mmap to make the actual allocation. In
+  // order to remember which one of the two was used for any block, we store an
+  // appropriate magic word next to the block.
+  static const int kMagicMalloc = 0xDEADBEEF;
+  static const int kMagicMMap = 0xABCDEFAB;
+
+  // This array will be filled with 0xCD, for use with memcmp.
+  static unsigned char kMagicDeletedBuffer[1024];
+  static pthread_once_t deleted_buffer_initialized_;
+  static bool deleted_buffer_initialized_no_pthreads_;
+
+ private:  // data layout
+
+                    // The four fields size1_,offset_,magic1_,alloc_type_
+                    // should together occupy a multiple of 16 bytes. (At the
+                    // moment, sizeof(size_t) == 4 or 8 depending on piii vs
+                    // k8, and 4 of those sum to 16 or 32 bytes).
+                    // This, combined with do_malloc's alignment guarantees,
+                    // ensures that SSE types can be stored into the returned
+                    // block, at &size2_.
+  size_t size1_;
+  size_t offset_;   // normally 0 unless memaligned memory
+                    // see comments in memalign() and FromRawPointer().
+  size_t magic1_;
+  size_t alloc_type_;
+  // here comes the actual data (variable length)
+  // ...
+  // then come the size2_ and magic2_, or a full page of mprotect-ed memory
+  // if the malloc_page_fence feature is enabled.
+  size_t size2_;
+  int magic2_;
+
+ private:  // static data and helpers
+
+  // Allocation map: stores the allocation type for each allocated object,
+  // or the type or'ed with kDeallocatedTypeBit
+  // for each formerly allocated object.
+  typedef AddressMap<int> AllocMap;
+  static AllocMap* alloc_map_;
+  // This protects alloc_map_ and consistent state of metadata
+  // for each still-allocated object in it.
+  // We use spin locks instead of pthread_mutex_t locks
+  // to prevent crashes via calls to pthread_mutex_(un)lock
+  // for the (de)allocations coming from pthreads initialization itself.
+  static SpinLock alloc_map_lock_;
+
+  // A queue of freed blocks.  Instead of releasing blocks to the allocator
+  // immediately, we put them in a queue, freeing them only when necessary
+  // to keep the total size of all the freed blocks below the limit set by
+  // FLAGS_max_free_queue_size.
+  static FreeQueue<MallocBlockQueueEntry>* free_queue_;
+
+  static size_t free_queue_size_;  // total size of blocks in free_queue_
+  // protects free_queue_ and free_queue_size_
+  static SpinLock free_queue_lock_;
+
+  // Names of allocation types (kMallocType, kNewType, kArrayNewType)
+  static const char* const kAllocName[];
+  // Names of corresponding deallocation types
+  static const char* const kDeallocName[];
+
+  static const char* AllocName(int type) {
+    return kAllocName[type & kAllocTypeMask];
+  }
+
+  static const char* DeallocName(int type) {
+    return kDeallocName[type & kAllocTypeMask];
+  }
+
+ private:  // helper accessors
+
+  bool IsMMapped() const { return kMagicMMap == magic1_; }
+
+  bool IsValidMagicValue(int value) const {
+    return kMagicMMap == value  ||  kMagicMalloc == value;
+  }
+
+  static size_t real_malloced_size(size_t size) {
+    return size + sizeof(MallocBlock);
+  }
+
+  /*
+   * Here we assume size of page is kMinAlign aligned,
+   * so if size is MALLOC_ALIGNMENT aligned too, then we could
+   * guarantee return address is also kMinAlign aligned, because
+   * mmap return address at nearby page boundary on Linux.
+   */
+  static size_t real_mmapped_size(size_t size) {
+    size_t tmp = size + MallocBlock::data_offset();
+    tmp = RoundUp(tmp, kMinAlign);
+    return tmp;
+  }
+
+  size_t real_size() {
+    return IsMMapped() ? real_mmapped_size(size1_) : real_malloced_size(size1_);
+  }
+
+  // NOTE: if the block is mmapped (that is, we're using the
+  // malloc_page_fence option) then there's no size2 or magic2
+  // (instead, the guard page begins where size2 would be).
+
+  size_t* size2_addr() { return (size_t*)((char*)&size2_ + size1_); }
+  const size_t* size2_addr() const {
+    return (const size_t*)((char*)&size2_ + size1_);
+  }
+
+  int* magic2_addr() { return (int*)(size2_addr() + 1); }
+  const int* magic2_addr() const { return (const int*)(size2_addr() + 1); }
+
+ private:  // other helpers
+
+  void Initialize(size_t size, int type) {
+    RAW_CHECK(IsValidMagicValue(magic1_), "");
+    // record us as allocated in the map
+    alloc_map_lock_.Lock();
+    if (!alloc_map_) {
+      void* p = do_malloc(sizeof(AllocMap));
+      alloc_map_ = new(p) AllocMap(do_malloc, do_free);
+    }
+    alloc_map_->Insert(data_addr(), type);
+    // initialize us
+    size1_ = size;
+    offset_ = 0;
+    alloc_type_ = type;
+    if (!IsMMapped()) {
+      *magic2_addr() = magic1_;
+      *size2_addr() = size;
+    }
+    alloc_map_lock_.Unlock();
+    memset(data_addr(), kMagicUninitializedByte, size);
+    if (!IsMMapped()) {
+      RAW_CHECK(size1_ == *size2_addr(), "should hold");
+      RAW_CHECK(magic1_ == *magic2_addr(), "should hold");
+    }
+  }
+
+  size_t CheckAndClear(int type) {
+    alloc_map_lock_.Lock();
+    CheckLocked(type);
+    if (!IsMMapped()) {
+      RAW_CHECK(size1_ == *size2_addr(), "should hold");
+    }
+    // record us as deallocated in the map
+    alloc_map_->Insert(data_addr(), type | kDeallocatedTypeBit);
+    alloc_map_lock_.Unlock();
+    // clear us
+    const size_t size = real_size();
+    memset(this, kMagicDeletedByte, size);
+    return size;
+  }
+
+  void CheckLocked(int type) const {
+    int map_type = 0;
+    const int* found_type =
+      alloc_map_ != NULL ? alloc_map_->Find(data_addr()) : NULL;
+    if (found_type == NULL) {
+      RAW_LOG(FATAL, "memory allocation bug: object at %p "
+                     "has never been allocated", data_addr());
+    } else {
+      map_type = *found_type;
+    }
+    if ((map_type & kDeallocatedTypeBit) != 0) {
+      RAW_LOG(FATAL, "memory allocation bug: object at %p "
+                     "has been already deallocated (it was allocated with %s)",
+                     data_addr(), AllocName(map_type & ~kDeallocatedTypeBit));
+    }
+    if (alloc_type_ == kMagicDeletedSizeT) {
+      RAW_LOG(FATAL, "memory stomping bug: a word before object at %p "
+                     "has been corrupted; or else the object has been already "
+                     "deallocated and our memory map has been corrupted",
+                     data_addr());
+    }
+    if (!IsValidMagicValue(magic1_)) {
+      RAW_LOG(FATAL, "memory stomping bug: a word before object at %p "
+                     "has been corrupted; "
+                     "or else our memory map has been corrupted and this is a "
+                     "deallocation for not (currently) heap-allocated object",
+                     data_addr());
+    }
+    if (!IsMMapped()) {
+      if (size1_ != *size2_addr()) {
+        RAW_LOG(FATAL, "memory stomping bug: a word after object at %p "
+                       "has been corrupted", data_addr());
+      }
+      if (!IsValidMagicValue(*magic2_addr())) {
+        RAW_LOG(FATAL, "memory stomping bug: a word after object at %p "
+                "has been corrupted", data_addr());
+      }
+    }
+    if (alloc_type_ != type) {
+      if ((alloc_type_ != MallocBlock::kMallocType) &&
+          (alloc_type_ != MallocBlock::kNewType)    &&
+          (alloc_type_ != MallocBlock::kArrayNewType)) {
+        RAW_LOG(FATAL, "memory stomping bug: a word before object at %p "
+                       "has been corrupted", data_addr());
+      }
+      RAW_LOG(FATAL, "memory allocation/deallocation mismatch at %p: "
+                     "allocated with %s being deallocated with %s",
+                     data_addr(), AllocName(alloc_type_), DeallocName(type));
+    }
+    if (alloc_type_ != map_type) {
+      RAW_LOG(FATAL, "memory stomping bug: our memory map has been corrupted : "
+                     "allocation at %p made with %s "
+                     "is recorded in the map to be made with %s",
+                     data_addr(), AllocName(alloc_type_),  AllocName(map_type));
+    }
+  }
+
+ public:  // public accessors
+
+  void* data_addr() { return (void*)&size2_; }
+  const void* data_addr() const { return (const void*)&size2_; }
+
+  static size_t data_offset() { return OFFSETOF_MEMBER(MallocBlock, size2_); }
+
+  size_t data_size() const { return size1_; }
+
+  void set_offset(int offset) { this->offset_ = offset; }
+
+ public:  // our main interface
+
+  static MallocBlock* Allocate(size_t size, int type) {
+    // Prevent an integer overflow / crash with large allocation sizes.
+    // TODO - Note that for a e.g. 64-bit size_t, max_size_t may not actually
+    // be the maximum value, depending on how the compiler treats ~0. The worst
+    // practical effect is that allocations are limited to 4Gb or so, even if
+    // the address space could take more.
+    static size_t max_size_t = ~0;
+    if (size > max_size_t - sizeof(MallocBlock)) {
+      RAW_LOG(ERROR, "Massive size passed to malloc: %" PRIuS "", size);
+      return NULL;
+    }
+    MallocBlock* b = NULL;
+    const bool use_malloc_page_fence = FLAGS_malloc_page_fence;
+#ifdef HAVE_MMAP
+    if (use_malloc_page_fence) {
+      // Put the block towards the end of the page and make the next page
+      // inaccessible. This will catch buffer overrun right when it happens.
+      size_t sz = real_mmapped_size(size);
+      int pagesize = getpagesize();
+      int num_pages = (sz + pagesize - 1) / pagesize + 1;
+      char* p = (char*) mmap(NULL, num_pages * pagesize, PROT_READ|PROT_WRITE,
+                             MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+      if (p == MAP_FAILED) {
+        // If the allocation fails, abort rather than returning NULL to
+        // malloc. This is because in most cases, the program will run out
+        // of memory in this mode due to tremendous amount of wastage. There
+        // is no point in propagating the error elsewhere.
+        RAW_LOG(FATAL, "Out of memory: possibly due to page fence overhead: %s",
+                strerror(errno));
+      }
+      // Mark the page after the block inaccessible
+      if (mprotect(p + (num_pages - 1) * pagesize, pagesize, PROT_NONE)) {
+        RAW_LOG(FATAL, "Guard page setup failed: %s", strerror(errno));
+      }
+      b = (MallocBlock*) (p + (num_pages - 1) * pagesize - sz);
+    } else {
+      b = (MallocBlock*) do_malloc(real_malloced_size(size));
+    }
+#else
+    b = (MallocBlock*) do_malloc(real_malloced_size(size));
+#endif
+
+    // It would be nice to output a diagnostic on allocation failure
+    // here, but logging (other than FATAL) requires allocating
+    // memory, which could trigger a nasty recursion. Instead, preserve
+    // malloc semantics and return NULL on failure.
+    if (b != NULL) {
+      b->magic1_ = use_malloc_page_fence ? kMagicMMap : kMagicMalloc;
+      b->Initialize(size, type);
+    }
+    return b;
+  }
+
+  void Deallocate(int type) {
+    if (IsMMapped()) {  // have to do this before CheckAndClear
+#ifdef HAVE_MMAP
+      int size = CheckAndClear(type);
+      int pagesize = getpagesize();
+      int num_pages = (size + pagesize - 1) / pagesize + 1;
+      char* p = (char*) this;
+      if (FLAGS_malloc_page_fence_never_reclaim  ||
+          !FLAGS_malloc_reclaim_memory) {
+        mprotect(p - (num_pages - 1) * pagesize + size,
+                 num_pages * pagesize, PROT_NONE);
+      } else {
+        munmap(p - (num_pages - 1) * pagesize + size, num_pages * pagesize);
+      }
+#endif
+    } else {
+      const size_t size = CheckAndClear(type);
+      if (FLAGS_malloc_reclaim_memory) {
+        // Instead of freeing the block immediately, push it onto a queue of
+        // recently freed blocks.  Free only enough blocks to keep from
+        // exceeding the capacity of the queue or causing the total amount of
+        // un-released memory in the queue from exceeding
+        // FLAGS_max_free_queue_size.
+        ProcessFreeQueue(this, size, FLAGS_max_free_queue_size);
+      }
+    }
+  }
+
+  static size_t FreeQueueSize() {
+    SpinLockHolder l(&free_queue_lock_);
+    return free_queue_size_;
+  }
+
+  static void ProcessFreeQueue(MallocBlock* b, size_t size,
+                               int max_free_queue_size) {
+    // MallocBlockQueueEntry are about 144 in size, so we can only
+    // use a small array of them on the stack.
+    MallocBlockQueueEntry entries[4];
+    int num_entries = 0;
+    MallocBlockQueueEntry new_entry(b, size);
+    free_queue_lock_.Lock();
+    if (free_queue_ == NULL)
+      free_queue_ = new FreeQueue<MallocBlockQueueEntry>;
+    RAW_CHECK(!free_queue_->Full(), "Free queue mustn't be full!");
+
+    if (b != NULL) {
+      free_queue_size_ += size + sizeof(MallocBlockQueueEntry);
+      free_queue_->Push(new_entry);
+    }
+
+    // Free blocks until the total size of unfreed blocks no longer exceeds
+    // max_free_queue_size, and the free queue has at least one free
+    // space in it.
+    while (free_queue_size_ > max_free_queue_size || free_queue_->Full()) {
+      RAW_CHECK(num_entries < arraysize(entries), "entries array overflow");
+      entries[num_entries] = free_queue_->Pop();
+      free_queue_size_ -=
+          entries[num_entries].size + sizeof(MallocBlockQueueEntry);
+      num_entries++;
+      if (num_entries == arraysize(entries)) {
+        // The queue will not be full at this point, so it is ok to
+        // release the lock.  The queue may still contain more than
+        // max_free_queue_size, but this is not a strict invariant.
+        free_queue_lock_.Unlock();
+        for (int i = 0; i < num_entries; i++) {
+          CheckForDanglingWrites(entries[i]);
+          do_free(entries[i].block);
+        }
+        num_entries = 0;
+        free_queue_lock_.Lock();
+      }
+    }
+    RAW_CHECK(free_queue_size_ >= 0, "Free queue size went negative!");
+    free_queue_lock_.Unlock();
+    for (int i = 0; i < num_entries; i++) {
+      CheckForDanglingWrites(entries[i]);
+      do_free(entries[i].block);
+    }
+  }
+
+  static void InitDeletedBuffer() {
+    memset(kMagicDeletedBuffer, kMagicDeletedByte, sizeof(kMagicDeletedBuffer));
+    deleted_buffer_initialized_no_pthreads_ = true;
+  }
+
+  static void CheckForDanglingWrites(const MallocBlockQueueEntry& queue_entry) {
+    // Initialize the buffer if necessary.
+    if (pthread_once)
+      pthread_once(&deleted_buffer_initialized_, &InitDeletedBuffer);
+    if (!deleted_buffer_initialized_no_pthreads_) {
+      // This will be the case on systems that don't link in pthreads,
+      // including on FreeBSD where pthread_once has a non-zero address
+      // (but doesn't do anything) even when pthreads isn't linked in.
+      InitDeletedBuffer();
+    }
+
+    const unsigned char* p =
+        reinterpret_cast<unsigned char*>(queue_entry.block);
+
+    static const size_t size_of_buffer = sizeof(kMagicDeletedBuffer);
+    const size_t size = queue_entry.size;
+    const size_t buffers = size / size_of_buffer;
+    const size_t remainder = size % size_of_buffer;
+    size_t buffer_idx;
+    for (buffer_idx = 0; buffer_idx < buffers; ++buffer_idx) {
+      CheckForCorruptedBuffer(queue_entry, buffer_idx, p, size_of_buffer);
+      p += size_of_buffer;
+    }
+    CheckForCorruptedBuffer(queue_entry, buffer_idx, p, remainder);
+  }
+
+  static void CheckForCorruptedBuffer(const MallocBlockQueueEntry& queue_entry,
+                                      size_t buffer_idx,
+                                      const unsigned char* buffer,
+                                      size_t size_of_buffer) {
+    if (memcmp(buffer, kMagicDeletedBuffer, size_of_buffer) == 0) {
+      return;
+    }
+
+    RAW_LOG(ERROR,
+            "Found a corrupted memory buffer in MallocBlock (may be offset "
+            "from user ptr): buffer index: %zd, buffer ptr: %p, size of "
+            "buffer: %zd", buffer_idx, buffer, size_of_buffer);
+
+    // The magic deleted buffer should only be 1024 bytes, but in case
+    // this changes, let's put an upper limit on the number of debug
+    // lines we'll output:
+    if (size_of_buffer <= 1024) {
+      for (int i = 0; i < size_of_buffer; ++i) {
+        if (buffer[i] != kMagicDeletedByte) {
+          RAW_LOG(ERROR, "Buffer byte %d is 0x%02x (should be 0x%02x).",
+                  i, buffer[i], kMagicDeletedByte);
+        }
+      }
+    } else {
+      RAW_LOG(ERROR, "Buffer too large to print corruption.");
+    }
+
+    const MallocBlock* b = queue_entry.block;
+    const size_t size = queue_entry.size;
+    if (queue_entry.num_deleter_pcs > 0) {
+      TracePrintf(STDERR_FILENO, "Deleted by thread %p\n",
+                  reinterpret_cast<void*>(
+                      PRINTABLE_PTHREAD(queue_entry.deleter_threadid)));
+
+      // We don't want to allocate or deallocate memory here, so we use
+      // placement-new.  It's ok that we don't destroy this, since we're
+      // just going to error-exit below anyway.  Union is for alignment.
+      union { void* alignment; char buf[sizeof(SymbolTable)]; } tablebuf;
+      SymbolTable* symbolization_table = new (tablebuf.buf) SymbolTable;
+      for (int i = 0; i < queue_entry.num_deleter_pcs; i++) {
+        // Symbolizes the previous address of pc because pc may be in the
+        // next function.  This may happen when the function ends with
+        // a call to a function annotated noreturn (e.g. CHECK).
+        char *pc = reinterpret_cast<char*>(queue_entry.deleter_pcs[i]);
+        symbolization_table->Add(pc - 1);
+      }
+      if (FLAGS_symbolize_stacktrace)
+        symbolization_table->Symbolize();
+      for (int i = 0; i < queue_entry.num_deleter_pcs; i++) {
+        char *pc = reinterpret_cast<char*>(queue_entry.deleter_pcs[i]);
+        TracePrintf(STDERR_FILENO, "    @ %p %s\n",
+                    pc, symbolization_table->GetSymbol(pc - 1));
+      }
+    } else {
+      RAW_LOG(ERROR,
+              "Skipping the printing of the deleter's stack!  Its stack was "
+              "not found; either the corruption occurred too early in "
+              "execution to obtain a stack trace or --max_free_queue_size was "
+              "set to 0.");
+    }
+
+    RAW_LOG(FATAL,
+            "Memory was written to after being freed.  MallocBlock: %p, user "
+            "ptr: %p, size: %zd.  If you can't find the source of the error, "
+            "try using ASan (http://code.google.com/p/address-sanitizer/), "
+            "Valgrind, or Purify, or study the "
+            "output of the deleter's stack printed above.",
+            b, b->data_addr(), size);
+  }
+
+  static MallocBlock* FromRawPointer(void* p) {
+    const size_t data_offset = MallocBlock::data_offset();
+    // Find the header just before client's memory.
+    MallocBlock *mb = reinterpret_cast<MallocBlock *>(
+                reinterpret_cast<char *>(p) - data_offset);
+    // If mb->alloc_type_ is kMagicDeletedSizeT, we're not an ok pointer.
+    if (mb->alloc_type_ == kMagicDeletedSizeT) {
+      RAW_LOG(FATAL, "memory allocation bug: object at %p has been already"
+                     " deallocated; or else a word before the object has been"
+                     " corrupted (memory stomping bug)", p);
+    }
+    // If mb->offset_ is zero (common case), mb is the real header.
+    // If mb->offset_ is non-zero, this block was allocated by debug
+    // memallign implementation, and mb->offset_ is the distance
+    // backwards to the real header from mb, which is a fake header.
+    if (mb->offset_ == 0) {
+      return mb;
+    }
+
+    MallocBlock *main_block = reinterpret_cast<MallocBlock *>(
+      reinterpret_cast<char *>(mb) - mb->offset_);
+
+    if (main_block->offset_ != 0) {
+      RAW_LOG(FATAL, "memory corruption bug: offset_ field is corrupted."
+              " Need 0 but got %x",
+              (unsigned)(main_block->offset_));
+    }
+    if (main_block >= p) {
+      RAW_LOG(FATAL, "memory corruption bug: offset_ field is corrupted."
+              " Detected main_block address overflow: %x",
+              (unsigned)(mb->offset_));
+    }
+    if (main_block->size2_addr() < p) {
+      RAW_LOG(FATAL, "memory corruption bug: offset_ field is corrupted."
+              " It points below it's own main_block: %x",
+              (unsigned)(mb->offset_));
+    }
+
+    return main_block;
+  }
+
+  static const MallocBlock* FromRawPointer(const void* p) {
+    // const-safe version: we just cast about
+    return FromRawPointer(const_cast<void*>(p));
+  }
+
+  void Check(int type) const {
+    alloc_map_lock_.Lock();
+    CheckLocked(type);
+    alloc_map_lock_.Unlock();
+  }
+
+  static bool CheckEverything() {
+    alloc_map_lock_.Lock();
+    if (alloc_map_ != NULL)  alloc_map_->Iterate(CheckCallback, 0);
+    alloc_map_lock_.Unlock();
+    return true;  // if we get here, we're okay
+  }
+
+  static bool MemoryStats(int* blocks, size_t* total,
+                          int histogram[kMallocHistogramSize]) {
+    memset(histogram, 0, kMallocHistogramSize * sizeof(int));
+    alloc_map_lock_.Lock();
+    stats_blocks_ = 0;
+    stats_total_ = 0;
+    stats_histogram_ = histogram;
+    if (alloc_map_ != NULL) alloc_map_->Iterate(StatsCallback, 0);
+    *blocks = stats_blocks_;
+    *total = stats_total_;
+    alloc_map_lock_.Unlock();
+    return true;
+  }
+
+ private:  // helpers for CheckEverything and MemoryStats
+
+  static void CheckCallback(const void* ptr, int* type, int dummy) {
+    if ((*type & kDeallocatedTypeBit) == 0) {
+      FromRawPointer(ptr)->CheckLocked(*type);
+    }
+  }
+
+  // Accumulation variables for StatsCallback protected by alloc_map_lock_
+  static int stats_blocks_;
+  static size_t stats_total_;
+  static int* stats_histogram_;
+
+  static void StatsCallback(const void* ptr, int* type, int dummy) {
+    if ((*type & kDeallocatedTypeBit) == 0) {
+      const MallocBlock* b = FromRawPointer(ptr);
+      b->CheckLocked(*type);
+      ++stats_blocks_;
+      size_t mysize = b->size1_;
+      int entry = 0;
+      stats_total_ += mysize;
+      while (mysize) {
+        ++entry;
+        mysize >>= 1;
+      }
+      RAW_CHECK(entry < kMallocHistogramSize,
+                "kMallocHistogramSize should be at least as large as log2 "
+                "of the maximum process memory size");
+      stats_histogram_[entry] += 1;
+    }
+  }
+};
+
+void DanglingWriteChecker() {
+  // Clear out the remaining free queue to check for dangling writes.
+  MallocBlock::ProcessFreeQueue(NULL, 0, 0);
+}
+
+// ========================================================================= //
+
+const int MallocBlock::kMagicMalloc;
+const int MallocBlock::kMagicMMap;
+
+MallocBlock::AllocMap* MallocBlock::alloc_map_ = NULL;
+SpinLock MallocBlock::alloc_map_lock_(SpinLock::LINKER_INITIALIZED);
+
+FreeQueue<MallocBlockQueueEntry>* MallocBlock::free_queue_ = NULL;
+size_t MallocBlock::free_queue_size_ = 0;
+SpinLock MallocBlock::free_queue_lock_(SpinLock::LINKER_INITIALIZED);
+
+unsigned char MallocBlock::kMagicDeletedBuffer[1024];
+pthread_once_t MallocBlock::deleted_buffer_initialized_ = PTHREAD_ONCE_INIT;
+bool MallocBlock::deleted_buffer_initialized_no_pthreads_ = false;
+
+const char* const MallocBlock::kAllocName[] = {
+  "malloc",
+  "new",
+  "new []",
+  NULL,
+};
+
+const char* const MallocBlock::kDeallocName[] = {
+  "free",
+  "delete",
+  "delete []",
+  NULL,
+};
+
+int MallocBlock::stats_blocks_;
+size_t MallocBlock::stats_total_;
+int* MallocBlock::stats_histogram_;
+
+// ========================================================================= //
+
+// The following cut-down version of printf() avoids
+// using stdio or ostreams.
+// This is to guarantee no recursive calls into
+// the allocator and to bound the stack space consumed.  (The pthread
+// manager thread in linuxthreads has a very small stack,
+// so fprintf can't be called.)
+static void TracePrintf(int fd, const char *fmt, ...) {
+  char buf[64];
+  int i = 0;
+  va_list ap;
+  va_start(ap, fmt);
+  const char *p = fmt;
+  char numbuf[25];
+  if (fd < 0) {
+    return;
+  }
+  numbuf[sizeof(numbuf)-1] = 0;
+  while (*p != '\0') {              // until end of format string
+    char *s = &numbuf[sizeof(numbuf)-1];
+    if (p[0] == '%' && p[1] != 0) {  // handle % formats
+      int64 l = 0;
+      unsigned long base = 0;
+      if (*++p == 's') {                            // %s
+        s = va_arg(ap, char *);
+      } else if (*p == 'l' && p[1] == 'd') {        // %ld
+        l = va_arg(ap, long);
+        base = 10;
+        p++;
+      } else if (*p == 'l' && p[1] == 'u') {        // %lu
+        l = va_arg(ap, unsigned long);
+        base = 10;
+        p++;
+      } else if (*p == 'z' && p[1] == 'u') {        // %zu
+        l = va_arg(ap, size_t);
+        base = 10;
+        p++;
+      } else if (*p == 'u') {                       // %u
+        l = va_arg(ap, unsigned int);
+        base = 10;
+      } else if (*p == 'd') {                       // %d
+        l = va_arg(ap, int);
+        base = 10;
+      } else if (*p == 'p') {                       // %p
+        l = va_arg(ap, intptr_t);
+        base = 16;
+      } else {
+        write(STDERR_FILENO, "Unimplemented TracePrintf format\n", 33);
+        write(STDERR_FILENO, p, 2);
+        write(STDERR_FILENO, "\n", 1);
+        abort();
+      }
+      p++;
+      if (base != 0) {
+        bool minus = (l < 0 && base == 10);
+        uint64 ul = minus? -l : l;
+        do {
+          *--s = "0123456789abcdef"[ul % base];
+          ul /= base;
+        } while (ul != 0);
+        if (base == 16) {
+          *--s = 'x';
+          *--s = '0';
+        } else if (minus) {
+          *--s = '-';
+        }
+      }
+    } else {                        // handle normal characters
+      *--s = *p++;
+    }
+    while (*s != 0) {
+      if (i == sizeof(buf)) {
+        write(fd, buf, i);
+        i = 0;
+      }
+      buf[i++] = *s++;
+    }
+  }
+  if (i != 0) {
+    write(fd, buf, i);
+  }
+  va_end(ap);
+}
+
+// Return the file descriptor we're writing a log to
+static int TraceFd() {
+  static int trace_fd = -1;
+  if (trace_fd == -1) {            // Open the trace file on the first call
+    const char *val = getenv("TCMALLOC_TRACE_FILE");
+    bool fallback_to_stderr = false;
+    if (!val) {
+      val = "/tmp/google.alloc";
+      fallback_to_stderr = true;
+    }
+    trace_fd = open(val, O_CREAT|O_TRUNC|O_WRONLY, 0666);
+    if (trace_fd == -1) {
+      if (fallback_to_stderr) {
+        trace_fd = 2;
+        TracePrintf(trace_fd, "Can't open %s.  Logging to stderr.\n", val);
+      } else {
+        TracePrintf(2, "Can't open %s.  Logging disabled.\n", val);
+      }
+    }
+    // Add a header to the log.
+    TracePrintf(trace_fd, "Trace started: %lu\n",
+                static_cast<unsigned long>(time(NULL)));
+    TracePrintf(trace_fd,
+                "func\tsize\tptr\tthread_id\tstack pcs for tools/symbolize\n");
+  }
+  return trace_fd;
+}
+
+// Print the hex stack dump on a single line.   PCs are separated by tabs.
+static void TraceStack(void) {
+  void *pcs[16];
+  int n = GetStackTrace(pcs, sizeof(pcs)/sizeof(pcs[0]), 0);
+  for (int i = 0; i != n; i++) {
+    TracePrintf(TraceFd(), "\t%p", pcs[i]);
+  }
+}
+
+// This protects MALLOC_TRACE, to make sure its info is atomically written.
+static SpinLock malloc_trace_lock(SpinLock::LINKER_INITIALIZED);
+
+#define MALLOC_TRACE(name, size, addr)                                  \
+  do {                                                                  \
+    if (FLAGS_malloctrace) {                                            \
+      SpinLockHolder l(&malloc_trace_lock);                             \
+      TracePrintf(TraceFd(), "%s\t%" PRIuS "\t%p\t%" GPRIuPTHREAD,      \
+                  name, size, addr, PRINTABLE_PTHREAD(pthread_self())); \
+      TraceStack();                                                     \
+      TracePrintf(TraceFd(), "\n");                                     \
+    }                                                                   \
+  } while (0)
+
+// ========================================================================= //
+
+// Write the characters buf[0, ..., size-1] to
+// the malloc trace buffer.
+// This function is intended for debugging,
+// and is not declared in any header file.
+// You must insert a declaration of it by hand when you need
+// to use it.
+void __malloctrace_write(const char *buf, size_t size) {
+  if (FLAGS_malloctrace) {
+    write(TraceFd(), buf, size);
+  }
+}
+
+// ========================================================================= //
+
+// General debug allocation/deallocation
+
+static inline void* DebugAllocate(size_t size, int type) {
+  MallocBlock* ptr = MallocBlock::Allocate(size, type);
+  if (ptr == NULL)  return NULL;
+  MALLOC_TRACE("malloc", size, ptr->data_addr());
+  return ptr->data_addr();
+}
+
+static inline void DebugDeallocate(void* ptr, int type) {
+  MALLOC_TRACE("free",
+               (ptr != 0 ? MallocBlock::FromRawPointer(ptr)->data_size() : 0),
+               ptr);
+  if (ptr)  MallocBlock::FromRawPointer(ptr)->Deallocate(type);
+}
+
+// ========================================================================= //
+
+// The following functions may be called via MallocExtension::instance()
+// for memory verification and statistics.
+class DebugMallocImplementation : public TCMallocImplementation {
+ public:
+  virtual bool GetNumericProperty(const char* name, size_t* value) {
+    bool result = TCMallocImplementation::GetNumericProperty(name, value);
+    if (result && (strcmp(name, "generic.current_allocated_bytes") == 0)) {
+      // Subtract bytes kept in the free queue
+      size_t qsize = MallocBlock::FreeQueueSize();
+      if (*value >= qsize) {
+        *value -= qsize;
+      }
+    }
+    return result;
+  }
+
+  virtual bool VerifyNewMemory(const void* p) {
+    if (p)  MallocBlock::FromRawPointer(p)->Check(MallocBlock::kNewType);
+    return true;
+  }
+
+  virtual bool VerifyArrayNewMemory(const void* p) {
+    if (p)  MallocBlock::FromRawPointer(p)->Check(MallocBlock::kArrayNewType);
+    return true;
+  }
+
+  virtual bool VerifyMallocMemory(const void* p) {
+    if (p)  MallocBlock::FromRawPointer(p)->Check(MallocBlock::kMallocType);
+    return true;
+  }
+
+  virtual bool VerifyAllMemory() {
+    return MallocBlock::CheckEverything();
+  }
+
+  virtual bool MallocMemoryStats(int* blocks, size_t* total,
+                                 int histogram[kMallocHistogramSize]) {
+    return MallocBlock::MemoryStats(blocks, total, histogram);
+  }
+
+  virtual size_t GetEstimatedAllocatedSize(size_t size) {
+    return size;
+  }
+
+  virtual size_t GetAllocatedSize(const void* p) {
+    if (p) {
+      RAW_CHECK(GetOwnership(p) != MallocExtension::kNotOwned,
+                "ptr not allocated by tcmalloc");
+      return MallocBlock::FromRawPointer(p)->data_size();
+    }
+    return 0;
+  }
+
+  virtual MallocExtension::Ownership GetOwnership(const void* p) {
+    if (!p) {
+      // nobody owns NULL
+      return MallocExtension::kNotOwned;
+    }
+
+    // FIXME: note that correct GetOwnership should not touch memory
+    // that is not owned by tcmalloc. Main implementation is using
+    // pagemap to discover if page in question is owned by us or
+    // not. But pagemap only has marks for first and last page of
+    // spans.  Note that if p was returned out of our memalign with
+    // big alignment, then it will point outside of marked pages. Also
+    // note that FromRawPointer call below requires touching memory
+    // before pointer in order to handle memalign-ed chunks
+    // (offset_). This leaves us with two options:
+    //
+    // * do FromRawPointer first and have possibility of crashing if
+    //   we're given not owned pointer
+    //
+    // * return incorrect ownership for those large memalign chunks
+    //
+    // I've decided to choose later, which appears to happen rarer and
+    // therefore is arguably a lesser evil
+
+    MallocExtension::Ownership rv = TCMallocImplementation::GetOwnership(p);
+    if (rv != MallocExtension::kOwned) {
+      return rv;
+    }
+
+    const MallocBlock* mb = MallocBlock::FromRawPointer(p);
+    return TCMallocImplementation::GetOwnership(mb);
+  }
+
+  virtual void GetFreeListSizes(vector<MallocExtension::FreeListInfo>* v) {
+    static const char* kDebugFreeQueue = "debug.free_queue";
+
+    TCMallocImplementation::GetFreeListSizes(v);
+
+    MallocExtension::FreeListInfo i;
+    i.type = kDebugFreeQueue;
+    i.min_object_size = 0;
+    i.max_object_size = numeric_limits<size_t>::max();
+    i.total_bytes_free = MallocBlock::FreeQueueSize();
+    v->push_back(i);
+  }
+
+ };
+
+static union {
+  char chars[sizeof(DebugMallocImplementation)];
+  void *ptr;
+} debug_malloc_implementation_space;
+
+REGISTER_MODULE_INITIALIZER(debugallocation, {
+#if (__cplusplus >= 201103L)
+    COMPILE_ASSERT(alignof(debug_malloc_implementation_space) >= alignof(DebugMallocImplementation),
+                   debug_malloc_implementation_space_is_not_properly_aligned);
+#endif
+  // Either we or valgrind will control memory management.  We
+  // register our extension if we're the winner. Otherwise let
+  // Valgrind use its own malloc (so don't register our extension).
+  if (!RunningOnValgrind()) {
+    DebugMallocImplementation *impl = new (debug_malloc_implementation_space.chars) DebugMallocImplementation();
+    MallocExtension::Register(impl);
+  }
+});
+
+REGISTER_MODULE_DESTRUCTOR(debugallocation, {
+  if (!RunningOnValgrind()) {
+    // When the program exits, check all blocks still in the free
+    // queue for corruption.
+    DanglingWriteChecker();
+  }
+});
+
+// ========================================================================= //
+
+struct debug_alloc_retry_data {
+  size_t size;
+  int new_type;
+};
+
+static void *retry_debug_allocate(void *arg) {
+  debug_alloc_retry_data *data = static_cast<debug_alloc_retry_data *>(arg);
+  return DebugAllocate(data->size, data->new_type);
+}
+
+// This is mostly the same a cpp_alloc in tcmalloc.cc.
+// TODO(csilvers): change Allocate() above to call cpp_alloc, so we
+// don't have to reproduce the logic here.  To make tc_new_mode work
+// properly, I think we'll need to separate out the logic of throwing
+// from the logic of calling the new-handler.
+inline void* debug_cpp_alloc(size_t size, int new_type, bool nothrow) {
+  void* p = DebugAllocate(size, new_type);
+  if (p != NULL) {
+    return p;
+  }
+  struct debug_alloc_retry_data data;
+  data.size = size;
+  data.new_type = new_type;
+  return handle_oom(retry_debug_allocate, &data,
+                    true, nothrow);
+}
+
+inline void* do_debug_malloc_or_debug_cpp_alloc(size_t size) {
+  void* p = DebugAllocate(size, MallocBlock::kMallocType);
+  if (p != NULL) {
+    return p;
+  }
+  struct debug_alloc_retry_data data;
+  data.size = size;
+  data.new_type = MallocBlock::kMallocType;
+  return handle_oom(retry_debug_allocate, &data,
+                    false, true);
+}
+
+// Exported routines
+
+extern "C" PERFTOOLS_DLL_DECL void* tc_malloc(size_t size) __THROW {
+  void* ptr = do_debug_malloc_or_debug_cpp_alloc(size);
+  MallocHook::InvokeNewHook(ptr, size);
+  return ptr;
+}
+
+extern "C" PERFTOOLS_DLL_DECL void tc_free(void* ptr) __THROW {
+  MallocHook::InvokeDeleteHook(ptr);
+  DebugDeallocate(ptr, MallocBlock::kMallocType);
+}
+
+extern "C" PERFTOOLS_DLL_DECL void* tc_calloc(size_t count, size_t size) __THROW {
+  // Overflow check
+  const size_t total_size = count * size;
+  if (size != 0 && total_size / size != count) return NULL;
+
+  void* block = do_debug_malloc_or_debug_cpp_alloc(total_size);
+  MallocHook::InvokeNewHook(block, total_size);
+  if (block)  memset(block, 0, total_size);
+  return block;
+}
+
+extern "C" PERFTOOLS_DLL_DECL void tc_cfree(void* ptr) __THROW {
+  MallocHook::InvokeDeleteHook(ptr);
+  DebugDeallocate(ptr, MallocBlock::kMallocType);
+}
+
+extern "C" PERFTOOLS_DLL_DECL void* tc_realloc(void* ptr, size_t size) __THROW {
+  if (ptr == NULL) {
+    ptr = do_debug_malloc_or_debug_cpp_alloc(size);
+    MallocHook::InvokeNewHook(ptr, size);
+    return ptr;
+  }
+  if (size == 0) {
+    MallocHook::InvokeDeleteHook(ptr);
+    DebugDeallocate(ptr, MallocBlock::kMallocType);
+    return NULL;
+  }
+  MallocBlock* old = MallocBlock::FromRawPointer(ptr);
+  old->Check(MallocBlock::kMallocType);
+  MallocBlock* p = MallocBlock::Allocate(size, MallocBlock::kMallocType);
+
+  // If realloc fails we are to leave the old block untouched and
+  // return null
+  if (p == NULL)  return NULL;
+
+  // if ptr was allocated via memalign, then old->data_size() is not
+  // start of user data. So we must be careful to copy only user-data
+  char *old_begin = (char *)old->data_addr();
+  char *old_end = old_begin + old->data_size();
+
+  ssize_t old_ssize = old_end - (char *)ptr;
+  CHECK_CONDITION(old_ssize >= 0);
+
+  size_t old_size = (size_t)old_ssize;
+  CHECK_CONDITION(old_size <= old->data_size());
+
+  memcpy(p->data_addr(), ptr, (old_size < size) ? old_size : size);
+  MallocHook::InvokeDeleteHook(ptr);
+  MallocHook::InvokeNewHook(p->data_addr(), size);
+  DebugDeallocate(ptr, MallocBlock::kMallocType);
+  MALLOC_TRACE("realloc", p->data_size(), p->data_addr());
+  return p->data_addr();
+}
+
+extern "C" PERFTOOLS_DLL_DECL void* tc_new(size_t size) {
+  void* ptr = debug_cpp_alloc(size, MallocBlock::kNewType, false);
+  MallocHook::InvokeNewHook(ptr, size);
+  if (ptr == NULL) {
+    RAW_LOG(FATAL, "Unable to allocate %" PRIuS " bytes: new failed.", size);
+  }
+  return ptr;
+}
+
+extern "C" PERFTOOLS_DLL_DECL void* tc_new_nothrow(size_t size, const std::nothrow_t&) __THROW {
+  void* ptr = debug_cpp_alloc(size, MallocBlock::kNewType, true);
+  MallocHook::InvokeNewHook(ptr, size);
+  return ptr;
+}
+
+extern "C" PERFTOOLS_DLL_DECL void tc_delete(void* p) __THROW {
+  MallocHook::InvokeDeleteHook(p);
+  DebugDeallocate(p, MallocBlock::kNewType);
+}
+
+// Some STL implementations explicitly invoke this.
+// It is completely equivalent to a normal delete (delete never throws).
+extern "C" PERFTOOLS_DLL_DECL void tc_delete_nothrow(void* p, const std::nothrow_t&) __THROW {
+  MallocHook::InvokeDeleteHook(p);
+  DebugDeallocate(p, MallocBlock::kNewType);
+}
+
+extern "C" PERFTOOLS_DLL_DECL void* tc_newarray(size_t size) {
+  void* ptr = debug_cpp_alloc(size, MallocBlock::kArrayNewType, false);
+  MallocHook::InvokeNewHook(ptr, size);
+  if (ptr == NULL) {
+    RAW_LOG(FATAL, "Unable to allocate %" PRIuS " bytes: new[] failed.", size);
+  }
+  return ptr;
+}
+
+extern "C" PERFTOOLS_DLL_DECL void* tc_newarray_nothrow(size_t size, const std::nothrow_t&)
+    __THROW {
+  void* ptr = debug_cpp_alloc(size, MallocBlock::kArrayNewType, true);
+  MallocHook::InvokeNewHook(ptr, size);
+  return ptr;
+}
+
+extern "C" PERFTOOLS_DLL_DECL void tc_deletearray(void* p) __THROW {
+  MallocHook::InvokeDeleteHook(p);
+  DebugDeallocate(p, MallocBlock::kArrayNewType);
+}
+
+// Some STL implementations explicitly invoke this.
+// It is completely equivalent to a normal delete (delete never throws).
+extern "C" PERFTOOLS_DLL_DECL void tc_deletearray_nothrow(void* p, const std::nothrow_t&) __THROW {
+  MallocHook::InvokeDeleteHook(p);
+  DebugDeallocate(p, MallocBlock::kArrayNewType);
+}
+
+// This is mostly the same as do_memalign in tcmalloc.cc.
+static void *do_debug_memalign(size_t alignment, size_t size) {
+  // Allocate >= size bytes aligned on "alignment" boundary
+  // "alignment" is a power of two.
+  void *p = 0;
+  RAW_CHECK((alignment & (alignment-1)) == 0, "must be power of two");
+  const size_t data_offset = MallocBlock::data_offset();
+  // Allocate "alignment-1" extra bytes to ensure alignment is possible, and
+  // a further data_offset bytes for an additional fake header.
+  size_t extra_bytes = data_offset + alignment - 1;
+  if (size + extra_bytes < size) return NULL;         // Overflow
+  p = DebugAllocate(size + extra_bytes, MallocBlock::kMallocType);
+  if (p != 0) {
+    intptr_t orig_p = reinterpret_cast<intptr_t>(p);
+    // Leave data_offset bytes for fake header, and round up to meet
+    // alignment.
+    p = reinterpret_cast<void *>(RoundUp(orig_p + data_offset, alignment));
+    // Create a fake header block with an offset_ that points back to the
+    // real header.  FromRawPointer uses this value.
+    MallocBlock *fake_hdr = reinterpret_cast<MallocBlock *>(
+                reinterpret_cast<char *>(p) - data_offset);
+    // offset_ is distance between real and fake headers.
+    // p is now end of fake header (beginning of client area),
+    // and orig_p is the end of the real header, so offset_
+    // is their difference.
+    //
+    // Note that other fields of fake_hdr are initialized with
+    // kMagicUninitializedByte
+    fake_hdr->set_offset(reinterpret_cast<intptr_t>(p) - orig_p);
+  }
+  return p;
+}
+
+struct memalign_retry_data {
+  size_t align;
+  size_t size;
+};
+
+static void *retry_debug_memalign(void *arg) {
+  memalign_retry_data *data = static_cast<memalign_retry_data *>(arg);
+  return do_debug_memalign(data->align, data->size);
+}
+
+inline void* do_debug_memalign_or_debug_cpp_memalign(size_t align,
+                                                     size_t size) {
+  void* p = do_debug_memalign(align, size);
+  if (p != NULL) {
+    return p;
+  }
+
+  struct memalign_retry_data data;
+  data.align = align;
+  data.size = size;
+  return handle_oom(retry_debug_memalign, &data,
+                    false, true);
+}
+
+extern "C" PERFTOOLS_DLL_DECL void* tc_memalign(size_t align, size_t size) __THROW {
+  void *p = do_debug_memalign_or_debug_cpp_memalign(align, size);
+  MallocHook::InvokeNewHook(p, size);
+  return p;
+}
+
+// Implementation taken from tcmalloc/tcmalloc.cc
+extern "C" PERFTOOLS_DLL_DECL int tc_posix_memalign(void** result_ptr, size_t align, size_t size)
+    __THROW {
+  if (((align % sizeof(void*)) != 0) ||
+      ((align & (align - 1)) != 0) ||
+      (align == 0)) {
+    return EINVAL;
+  }
+
+  void* result = do_debug_memalign_or_debug_cpp_memalign(align, size);
+  MallocHook::InvokeNewHook(result, size);
+  if (result == NULL) {
+    return ENOMEM;
+  } else {
+    *result_ptr = result;
+    return 0;
+  }
+}
+
+extern "C" PERFTOOLS_DLL_DECL void* tc_valloc(size_t size) __THROW {
+  // Allocate >= size bytes starting on a page boundary
+  void *p = do_debug_memalign_or_debug_cpp_memalign(getpagesize(), size);
+  MallocHook::InvokeNewHook(p, size);
+  return p;
+}
+
+extern "C" PERFTOOLS_DLL_DECL void* tc_pvalloc(size_t size) __THROW {
+  // Round size up to a multiple of pages
+  // then allocate memory on a page boundary
+  int pagesize = getpagesize();
+  size = RoundUp(size, pagesize);
+  if (size == 0) {     // pvalloc(0) should allocate one page, according to
+    size = pagesize;   // http://man.free4web.biz/man3/libmpatrol.3.html
+  }
+  void *p = do_debug_memalign_or_debug_cpp_memalign(pagesize, size);
+  MallocHook::InvokeNewHook(p, size);
+  return p;
+}
+
+// malloc_stats just falls through to the base implementation.
+extern "C" PERFTOOLS_DLL_DECL void tc_malloc_stats(void) __THROW {
+  do_malloc_stats();
+}
+
+extern "C" PERFTOOLS_DLL_DECL int tc_mallopt(int cmd, int value) __THROW {
+  return do_mallopt(cmd, value);
+}
+
+#ifdef HAVE_STRUCT_MALLINFO
+extern "C" PERFTOOLS_DLL_DECL struct mallinfo tc_mallinfo(void) __THROW {
+  return do_mallinfo();
+}
+#endif
+
+extern "C" PERFTOOLS_DLL_DECL size_t tc_malloc_size(void* ptr) __THROW {
+  return MallocExtension::instance()->GetAllocatedSize(ptr);
+}
+
+extern "C" PERFTOOLS_DLL_DECL void* tc_malloc_skip_new_handler(size_t size) __THROW {
+  void* result = DebugAllocate(size, MallocBlock::kMallocType);
+  MallocHook::InvokeNewHook(result, size);
+  return result;
+}