Revert 126715 - Update the tcmalloc vendor branch to r144 (gperftools 2.0).

third_party/tcmalloc/vendor/src/malloc_hook.cc

Index: third_party/tcmalloc/vendor/src/malloc_hook.cc
===================================================================
--- third_party/tcmalloc/vendor/src/malloc_hook.cc	(revision 126727)
+++ third_party/tcmalloc/vendor/src/malloc_hook.cc	(working copy)
@@ -46,11 +46,12 @@
 #include <stdint.h>
 #endif
 #include <algorithm>
+#include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/spinlock.h"
 #include "maybe_threads.h"
 #include "malloc_hook-inl.h"
-#include <gperftools/malloc_hook.h>
+#include <google/malloc_hook.h>
 
 // This #ifdef should almost never be set.  Set NO_TCMALLOC_SAMPLES if
 // you're porting to a system where you really can't get a stacktrace.
@@ -58,7 +59,7 @@
   // We use #define so code compiles even if you #include stacktrace.h somehow.
 # define GetStackTrace(stack, depth, skip)  (0)
 #else
-# include <gperftools/stacktrace.h>
+# include <google/stacktrace.h>
 #endif
 
 // __THROW is defined in glibc systems.  It means, counter-intuitively,
@@ -203,8 +204,14 @@
 
 template <typename T>
 bool HookList<T>::Add(T value_as_t) {
-  AtomicWord value = bit_cast<AtomicWord>(value_as_t);
+  // Note: we need to check this _before_ reinterpret_cast, since
+  // reinterpret_cast may include random junk from memory.
+  if (value_as_t == 0) {
+    return false;
+  }
+  AtomicWord value = reinterpret_cast<const AtomicWord&>(value_as_t);
   if (value == 0) {
+    // This should not actually happen, but just to be sure...
     return false;
   }
   SpinLockHolder l(&hooklist_spinlock);
@@ -233,7 +240,8 @@
   SpinLockHolder l(&hooklist_spinlock);
   AtomicWord hooks_end = base::subtle::Acquire_Load(&priv_end);
   int index = 0;
-  while (index < hooks_end && value_as_t != bit_cast<T>(
+  // Note: we need to cast back to T since T may be smaller than AtomicWord.
+  while (index < hooks_end && value_as_t != reinterpret_cast<T>(
              base::subtle::Acquire_Load(&priv_data[index]))) {
     ++index;
   }
@@ -260,7 +268,7 @@
   for (int i = 0; i < hooks_end && n > 0; ++i) {
     AtomicWord data = base::subtle::Acquire_Load(&priv_data[i]);
     if (data != 0) {
-      *output_array++ = bit_cast<T>(data);
+      *output_array++ = reinterpret_cast<const T&>(data);
       ++actual_hooks_end;
       --n;
     }
@@ -697,7 +705,9 @@
 #if defined(__linux)
 # include "malloc_hook_mmap_linux.h"
 
-#elif defined(__FreeBSD__)
+// This code doesn't even compile on my freebsd 8.1 (x86_64) system,
+// so comment it out for now.  TODO(csilvers): fix this!
+#elif 0 && defined(__FreeBSD__)
 # include "malloc_hook_mmap_freebsd.h"
 
 #else