Down-integrate from internal branch

15 files changed, 1909 insertions, 14 deletions

diff --git a/src/google/protobuf/stubs/common.cc b/src/google/protobuf/stubs/common.cc
index 7b15be44..16d78528 100644
--- a/src/google/protobuf/stubs/common.cc
+++ b/src/google/protobuf/stubs/common.cc
@@ -320,6 +320,24 @@ void Mutex::AssertHeld() {
 #endif
 
 // ===================================================================
+// emulates google3/util/endian/endian.h
+//
+// TODO(xiaofeng): PROTOBUF_LITTLE_ENDIAN is unfortunately defined in
+// google/protobuf/io/coded_stream.h and therefore can not be used here.
+// Maybe move that macro definition here in the furture.
+uint32 ghtonl(uint32 x) {
+  union {
+    uint32 result;
+    uint8 result_array[4];
+  };
+  result_array[0] = static_cast<uint8>(x >> 24);
+  result_array[1] = static_cast<uint8>((x >> 16) & 0xFF);
+  result_array[2] = static_cast<uint8>((x >> 8) & 0xFF);
+  result_array[3] = static_cast<uint8>(x & 0xFF);
+  return result;
+}
+
+// ===================================================================
 // Shutdown support.
 
 namespace internal {
diff --git a/src/google/protobuf/stubs/common.h b/src/google/protobuf/stubs/common.h
index 7f5fd4d2..07ae5307 100644
--- a/src/google/protobuf/stubs/common.h
+++ b/src/google/protobuf/stubs/common.h
@@ -341,6 +341,12 @@ inline To down_cast(From* f) {                   // so we only accept pointers
   return static_cast<To>(f);
 }
 
+// Simplified down_cast for reference type.
+template<typename To, typename From>
+inline To down_cast(From& f) {
+  return static_cast<To>(f);
+}
+
 }  // namespace internal
 
 // We made these internal so that they would show up as such in the docs,
@@ -686,6 +692,7 @@ class LIBPROTOBUF_EXPORT LogFinisher {
 #undef GOOGLE_CHECK_LE
 #undef GOOGLE_CHECK_GT
 #undef GOOGLE_CHECK_GE
+#undef GOOGLE_CHECK_NOTNULL
 
 #undef GOOGLE_DLOG
 #undef GOOGLE_DCHECK
@@ -712,6 +719,18 @@ class LIBPROTOBUF_EXPORT LogFinisher {
 #define GOOGLE_CHECK_GT(A, B) GOOGLE_CHECK((A) >  (B))
 #define GOOGLE_CHECK_GE(A, B) GOOGLE_CHECK((A) >= (B))
 
+namespace internal {
+template<typename T>
+T* CheckNotNull(const char *file, int line, const char *name, T* val) {
+  if (val == NULL) {
+    GOOGLE_LOG(FATAL) << name;
+  }
+  return val;
+}
+}  // namespace internal
+#define GOOGLE_CHECK_NOTNULL(A) \
+  internal::CheckNotNull(__FILE__, __LINE__, "'" #A "' must not be NULL", (A))
+
 #ifdef NDEBUG
 
 #define GOOGLE_DLOG GOOGLE_LOG_IF(INFO, false)
@@ -1136,20 +1155,10 @@ using internal::WriterMutexLock;
 using internal::MutexLockMaybe;
 
 // ===================================================================
-// from google3/base/type_traits.h
+// from google3/util/utf8/public/unilib.h
 
 namespace internal {
 
-// Specified by TR1 [4.7.4] Pointer modifications.
-template<typename T> struct remove_pointer { typedef T type; };
-template<typename T> struct remove_pointer<T*> { typedef T type; };
-template<typename T> struct remove_pointer<T* const> { typedef T type; };
-template<typename T> struct remove_pointer<T* volatile> { typedef T type; };
-template<typename T> struct remove_pointer<T* const volatile> {
-  typedef T type; };
-
-// ===================================================================
-
 // Checks if the buffer contains structurally-valid UTF-8.  Implemented in
 // structurally_valid.cc.
 LIBPROTOBUF_EXPORT bool IsStructurallyValidUTF8(const char* buf, int len);
@@ -1157,6 +1166,10 @@ LIBPROTOBUF_EXPORT bool IsStructurallyValidUTF8(const char* buf, int len);
 }  // namespace internal
 
 // ===================================================================
+// from google3/util/endian/endian.h
+LIBPROTOBUF_EXPORT uint32 ghtonl(uint32 x);
+
+// ===================================================================
 // Shutdown support.
 
 // Shut down the entire protocol buffers library, deleting all static-duration
diff --git a/src/google/protobuf/stubs/hash.h b/src/google/protobuf/stubs/hash.h
index 822d6050..f7d10712 100644
--- a/src/google/protobuf/stubs/hash.h
+++ b/src/google/protobuf/stubs/hash.h
@@ -90,12 +90,16 @@ template <typename Key, typename Data,
           typename HashFcn = hash<Key>,
           typename EqualKey = int >
 class hash_map : public std::map<Key, Data, HashFcn> {
+ public:
+  hash_map(int = 0) {}
 };
 
 template <typename Key,
           typename HashFcn = hash<Key>,
           typename EqualKey = int >
 class hash_set : public std::set<Key, HashFcn> {
+ public:
+  hash_set(int = 0) {}
 };
 
 #elif defined(_MSC_VER) && !defined(_STLPORT_VERSION)
@@ -123,6 +127,8 @@ template <typename Key, typename Data,
           typename EqualKey = int >
 class hash_map : public HASH_NAMESPACE::hash_map<
     Key, Data, HashFcn> {
+ public:
+  hash_map(int = 0) {}
 };
 
 template <typename Key,
@@ -130,6 +136,8 @@ template <typename Key,
           typename EqualKey = int >
 class hash_set : public HASH_NAMESPACE::hash_set<
     Key, HashFcn> {
+ public:
+  hash_set(int = 0) {}
 };
 
 #else
@@ -163,6 +171,8 @@ template <typename Key, typename Data,
           typename EqualKey = std::equal_to<Key> >
 class hash_map : public HASH_NAMESPACE::HASH_MAP_CLASS<
     Key, Data, HashFcn, EqualKey> {
+ public:
+  hash_map(int = 0) {}
 };
 
 template <typename Key,
@@ -170,6 +180,8 @@ template <typename Key,
           typename EqualKey = std::equal_to<Key> >
 class hash_set : public HASH_NAMESPACE::HASH_SET_CLASS<
     Key, HashFcn, EqualKey> {
+ public:
+  hash_set(int = 0) {}
 };
 
 #endif
diff --git a/src/google/protobuf/stubs/map-util.h b/src/google/protobuf/stubs/map-util.h
index f5c9d6b6..775848b9 100644
--- a/src/google/protobuf/stubs/map-util.h
+++ b/src/google/protobuf/stubs/map-util.h
@@ -68,6 +68,30 @@ FindOrNull(const Collection& collection,
   return &it->second;
 }
 
+// Perform a lookup in a map or hash_map, assuming that the key exists.
+// Crash if it does not.
+//
+// This is intended as a replacement for operator[] as an rvalue (for reading)
+// when the key is guaranteed to exist.
+//
+// operator[] is discouraged for several reasons:
+//  * It has a side-effect of inserting missing keys
+//  * It is not thread-safe (even when it is not inserting, it can still
+//      choose to resize the underlying storage)
+//  * It invalidates iterators (when it chooses to resize)
+//  * It default constructs a value object even if it doesn't need to
+//
+// This version assumes the key is printable, and includes it in the fatal log
+// message.
+template <class Collection>
+const typename Collection::value_type::second_type&
+FindOrDie(const Collection& collection,
+          const typename Collection::value_type::first_type& key) {
+  typename Collection::const_iterator it = collection.find(key);
+  GOOGLE_CHECK(it != collection.end()) << "Map key not found: " << key;
+  return it->second;
+}
+
 // Perform a lookup in a map or hash_map whose values are pointers.
 // If the key is present a const pointer to the associated value is returned,
 // otherwise a NULL pointer is returned.
diff --git a/src/google/protobuf/stubs/stl_util.h b/src/google/protobuf/stubs/stl_util.h
new file mode 100644
index 00000000..9021dada
--- /dev/null
+++ b/src/google/protobuf/stubs/stl_util.h
@@ -0,0 +1,121 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// 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.
+
+// from google3/util/gtl/stl_util.h
+
+#ifndef GOOGLE_PROTOBUF_STUBS_STL_UTIL_H__
+#define GOOGLE_PROTOBUF_STUBS_STL_UTIL_H__
+
+#include <google/protobuf/stubs/common.h>
+
+namespace google {
+namespace protobuf {
+
+// STLDeleteContainerPointers()
+//  For a range within a container of pointers, calls delete
+//  (non-array version) on these pointers.
+// NOTE: for these three functions, we could just implement a DeleteObject
+// functor and then call for_each() on the range and functor, but this
+// requires us to pull in all of algorithm.h, which seems expensive.
+// For hash_[multi]set, it is important that this deletes behind the iterator
+// because the hash_set may call the hash function on the iterator when it is
+// advanced, which could result in the hash function trying to deference a
+// stale pointer.
+template <class ForwardIterator>
+void STLDeleteContainerPointers(ForwardIterator begin,
+                                ForwardIterator end) {
+  while (begin != end) {
+    ForwardIterator temp = begin;
+    ++begin;
+    delete *temp;
+  }
+}
+
+// Inside Google, this function implements a horrible, disgusting hack in which
+// we reach into the string's private implementation and resize it without
+// initializing the new bytes.  In some cases doing this can significantly
+// improve performance.  However, since it's totally non-portable it has no
+// place in open source code.  Feel free to fill this function in with your
+// own disgusting hack if you want the perf boost.
+inline void STLStringResizeUninitialized(string* s, size_t new_size) {
+  s->resize(new_size);
+}
+
+// Return a mutable char* pointing to a string's internal buffer,
+// which may not be null-terminated. Writing through this pointer will
+// modify the string.
+//
+// string_as_array(&str)[i] is valid for 0 <= i < str.size() until the
+// next call to a string method that invalidates iterators.
+//
+// As of 2006-04, there is no standard-blessed way of getting a
+// mutable reference to a string's internal buffer. However, issue 530
+// (http://www.open-std.org/JTC1/SC22/WG21/docs/lwg-active.html#530)
+// proposes this as the method. According to Matt Austern, this should
+// already work on all current implementations.
+inline char* string_as_array(string* str) {
+  // DO NOT USE const_cast<char*>(str->data())! See the unittest for why.
+  return str->empty() ? NULL : &*str->begin();
+}
+
+// STLDeleteElements() deletes all the elements in an STL container and clears
+// the container.  This function is suitable for use with a vector, set,
+// hash_set, or any other STL container which defines sensible begin(), end(),
+// and clear() methods.
+//
+// If container is NULL, this function is a no-op.
+//
+// As an alternative to calling STLDeleteElements() directly, consider
+// ElementDeleter (defined below), which ensures that your container's elements
+// are deleted when the ElementDeleter goes out of scope.
+template <class T>
+void STLDeleteElements(T *container) {
+  if (!container) return;
+  STLDeleteContainerPointers(container->begin(), container->end());
+  container->clear();
+}
+
+// Given an STL container consisting of (key, value) pairs, STLDeleteValues
+// deletes all the "value" components and clears the container.  Does nothing
+// in the case it's given a NULL pointer.
+
+template <class T>
+void STLDeleteValues(T *v) {
+  if (!v) return;
+  for (typename T::iterator i = v->begin(); i != v->end(); ++i) {
+    delete i->second;
+  }
+  v->clear();
+}
+
+}  // namespace protobuf
+}  // namespace google
+
+#endif  // GOOGLE_PROTOBUF_STUBS_STL_UTIL_H__
diff --git a/src/google/protobuf/stubs/stringprintf.cc b/src/google/protobuf/stubs/stringprintf.cc
new file mode 100644
index 00000000..d66a497a
--- /dev/null
+++ b/src/google/protobuf/stubs/stringprintf.cc
@@ -0,0 +1,170 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2012 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// 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.
+
+// from google3/base/stringprintf.cc
+
+#include <google/protobuf/stubs/stringprintf.h>
+
+#include <errno.h>
+#include <stdarg.h> // For va_list and related operations
+#include <stdio.h> // MSVC requires this for _vsnprintf
+#include <vector>
+#include <google/protobuf/stubs/common.h>
+#include <google/protobuf/testing/googletest.h>
+
+namespace google {
+namespace protobuf {
+
+#ifdef _MSC_VER
+enum { IS_COMPILER_MSVC = 1 };
+#else
+enum { IS_COMPILER_MSVC = 0 };
+#endif
+
+void StringAppendV(string* dst, const char* format, va_list ap) {
+  // First try with a small fixed size buffer
+  static const int kSpaceLength = 1024;
+  char space[kSpaceLength];
+
+  // It's possible for methods that use a va_list to invalidate
+  // the data in it upon use.  The fix is to make a copy
+  // of the structure before using it and use that copy instead.
+  va_list backup_ap;
+  va_copy(backup_ap, ap);
+  int result = vsnprintf(space, kSpaceLength, format, backup_ap);
+  va_end(backup_ap);
+
+  if (result < kSpaceLength) {
+    if (result >= 0) {
+      // Normal case -- everything fit.
+      dst->append(space, result);
+      return;
+    }
+
+    if (IS_COMPILER_MSVC) {
+      // Error or MSVC running out of space.  MSVC 8.0 and higher
+      // can be asked about space needed with the special idiom below:
+      va_copy(backup_ap, ap);
+      result = vsnprintf(NULL, 0, format, backup_ap);
+      va_end(backup_ap);
+    }
+
+    if (result < 0) {
+      // Just an error.
+      return;
+    }
+  }
+
+  // Increase the buffer size to the size requested by vsnprintf,
+  // plus one for the closing \0.
+  int length = result+1;
+  char* buf = new char[length];
+
+  // Restore the va_list before we use it again
+  va_copy(backup_ap, ap);
+  result = vsnprintf(buf, length, format, backup_ap);
+  va_end(backup_ap);
+
+  if (result >= 0 && result < length) {
+    // It fit
+    dst->append(buf, result);
+  }
+  delete[] buf;
+}
+
+
+string StringPrintf(const char* format, ...) {
+  va_list ap;
+  va_start(ap, format);
+  string result;
+  StringAppendV(&result, format, ap);
+  va_end(ap);
+  return result;
+}
+
+const string& SStringPrintf(string* dst, const char* format, ...) {
+  va_list ap;
+  va_start(ap, format);
+  dst->clear();
+  StringAppendV(dst, format, ap);
+  va_end(ap);
+  return *dst;
+}
+
+void StringAppendF(string* dst, const char* format, ...) {
+  va_list ap;
+  va_start(ap, format);
+  StringAppendV(dst, format, ap);
+  va_end(ap);
+}
+
+// Max arguments supported by StringPrintVector
+const int kStringPrintfVectorMaxArgs = 32;
+
+// An empty block of zero for filler arguments.  This is const so that if
+// printf tries to write to it (via %n) then the program gets a SIGSEGV
+// and we can fix the problem or protect against an attack.
+static const char string_printf_empty_block[256] = { '\0' };
+
+string StringPrintfVector(const char* format, const vector<string>& v) {
+  GOOGLE_CHECK_LE(v.size(), kStringPrintfVectorMaxArgs)
+      << "StringPrintfVector currently only supports up to "
+      << kStringPrintfVectorMaxArgs << " arguments. "
+      << "Feel free to add support for more if you need it.";
+
+  // Add filler arguments so that bogus format+args have a harder time
+  // crashing the program, corrupting the program (%n),
+  // or displaying random chunks of memory to users.
+
+  const char* cstr[kStringPrintfVectorMaxArgs];
+  for (int i = 0; i < v.size(); ++i) {
+    cstr[i] = v[i].c_str();
+  }
+  for (int i = v.size(); i < GOOGLE_ARRAYSIZE(cstr); ++i) {
+    cstr[i] = &string_printf_empty_block[0];
+  }
+
+  // I do not know any way to pass kStringPrintfVectorMaxArgs arguments,
+  // or any way to build a va_list by hand, or any API for printf
+  // that accepts an array of arguments.  The best I can do is stick
+  // this COMPILE_ASSERT right next to the actual statement.
+
+  GOOGLE_COMPILE_ASSERT(kStringPrintfVectorMaxArgs == 32, arg_count_mismatch);
+  return StringPrintf(format,
+                      cstr[0], cstr[1], cstr[2], cstr[3], cstr[4],
+                      cstr[5], cstr[6], cstr[7], cstr[8], cstr[9],
+                      cstr[10], cstr[11], cstr[12], cstr[13], cstr[14],
+                      cstr[15], cstr[16], cstr[17], cstr[18], cstr[19],
+                      cstr[20], cstr[21], cstr[22], cstr[23], cstr[24],
+                      cstr[25], cstr[26], cstr[27], cstr[28], cstr[29],
+                      cstr[30], cstr[31]);
+}
+}  // namespace protobuf
+}  // namespace google
diff --git a/src/google/protobuf/stubs/stringprintf.h b/src/google/protobuf/stubs/stringprintf.h
new file mode 100644
index 00000000..573f30f3
--- /dev/null
+++ b/src/google/protobuf/stubs/stringprintf.h
@@ -0,0 +1,76 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2012 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// 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.
+
+// from google3/base/stringprintf.h
+//
+// Printf variants that place their output in a C++ string.
+//
+// Usage:
+//      string result = StringPrintf("%d %s\n", 10, "hello");
+//      SStringPrintf(&result, "%d %s\n", 10, "hello");
+//      StringAppendF(&result, "%d %s\n", 20, "there");
+
+#ifndef GOOGLE_PROTOBUF_STUBS_STRINGPRINTF_H
+#define GOOGLE_PROTOBUF_STUBS_STRINGPRINTF_H
+
+#include <stdarg.h>
+#include <string>
+#include <vector>
+
+#include <google/protobuf/stubs/common.h>
+
+namespace google {
+namespace protobuf {
+
+// Return a C++ string
+extern string StringPrintf(const char* format, ...);
+
+// Store result into a supplied string and return it
+extern const string& SStringPrintf(string* dst, const char* format, ...);
+
+// Append result to a supplied string
+extern void StringAppendF(string* dst, const char* format, ...);
+
+// Lower-level routine that takes a va_list and appends to a specified
+// string.  All other routines are just convenience wrappers around it.
+extern void StringAppendV(string* dst, const char* format, va_list ap);
+
+// The max arguments supported by StringPrintfVector
+extern const int kStringPrintfVectorMaxArgs;
+
+// You can use this version when all your arguments are strings, but
+// you don't know how many arguments you'll have at compile time.
+// StringPrintfVector will LOG(FATAL) if v.size() > kStringPrintfVectorMaxArgs
+extern string StringPrintfVector(const char* format, const vector<string>& v);
+
+}  // namespace protobuf
+}  // namespace google
+
+#endif  // GOOGLE_PROTOBUF_STUBS_STRINGPRINTF_H
diff --git a/src/google/protobuf/stubs/stringprintf_unittest.cc b/src/google/protobuf/stubs/stringprintf_unittest.cc
new file mode 100644
index 00000000..5cf7fffc
--- /dev/null
+++ b/src/google/protobuf/stubs/stringprintf_unittest.cc
@@ -0,0 +1,152 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2012 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// 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.
+
+// from google3/base/stringprintf_unittest.cc
+
+#include <google/protobuf/stubs/stringprintf.h>
+
+#include <cerrno>
+#include <string>
+
+#include <google/protobuf/testing/googletest.h>
+#include <gtest/gtest.h>
+
+namespace google {
+namespace protobuf {
+namespace {
+
+TEST(StringPrintfTest, Empty) {
+#if 0
+  // gcc 2.95.3, gcc 4.1.0, and gcc 4.2.2 all warn about this:
+  // warning: zero-length printf format string.
+  // so we do not allow them in google3.
+  EXPECT_EQ("", StringPrintf(""));
+#endif
+  EXPECT_EQ("", StringPrintf("%s", string().c_str()));
+  EXPECT_EQ("", StringPrintf("%s", ""));
+}
+
+TEST(StringPrintfTest, Misc) {
+// MSVC does not support $ format specifier.
+#if !defined(COMPILER_MSVC)
+  EXPECT_EQ("123hello w", StringPrintf("%3$d%2$s %1$c", 'w', "hello", 123));
+#endif  // !COMPILER_MSVC
+}
+
+TEST(StringAppendFTest, Empty) {
+  string value("Hello");
+  const char* empty = "";
+  StringAppendF(&value, "%s", empty);
+  EXPECT_EQ("Hello", value);
+}
+
+TEST(StringAppendFTest, EmptyString) {
+  string value("Hello");
+  StringAppendF(&value, "%s", "");
+  EXPECT_EQ("Hello", value);
+}
+
+TEST(StringAppendFTest, String) {
+  string value("Hello");
+  StringAppendF(&value, " %s", "World");
+  EXPECT_EQ("Hello World", value);
+}
+
+TEST(StringAppendFTest, Int) {
+  string value("Hello");
+  StringAppendF(&value, " %d", 123);
+  EXPECT_EQ("Hello 123", value);
+}
+
+TEST(StringPrintfTest, Multibyte) {
+  // If we are in multibyte mode and feed invalid multibyte sequence,
+  // StringPrintf should return an empty string instead of running
+  // out of memory while trying to determine destination buffer size.
+  // see b/4194543.
+
+  char* old_locale = setlocale(LC_CTYPE, NULL);
+  // Push locale with multibyte mode
+  setlocale(LC_CTYPE, "en_US.utf8");
+
+  const char kInvalidCodePoint[] = "\375\067s";
+  string value = StringPrintf("%.*s", 3, kInvalidCodePoint);
+
+  // In some versions of glibc (e.g. eglibc-2.11.1, aka GRTEv2), snprintf
+  // returns error given an invalid codepoint. Other versions
+  // (e.g. eglibc-2.15, aka pre-GRTEv3) emit the codepoint verbatim.
+  // We test that the output is one of the above.
+  EXPECT_TRUE(value.empty() || value == kInvalidCodePoint);
+
+  // Repeat with longer string, to make sure that the dynamically
+  // allocated path in StringAppendV is handled correctly.
+  int n = 2048;
+  char* buf = new char[n+1];
+  memset(buf, ' ', n-3);
+  memcpy(buf + n - 3, kInvalidCodePoint, 4);
+  value =  StringPrintf("%.*s", n, buf);
+  // See GRTEv2 vs. GRTEv3 comment above.
+  EXPECT_TRUE(value.empty() || value == buf);
+  delete[] buf;
+
+  setlocale(LC_CTYPE, old_locale);
+}
+
+TEST(StringPrintfTest, NoMultibyte) {
+  // No multibyte handling, but the string contains funny chars.
+  char* old_locale = setlocale(LC_CTYPE, NULL);
+  setlocale(LC_CTYPE, "POSIX");
+  string value = StringPrintf("%.*s", 3, "\375\067s");
+  setlocale(LC_CTYPE, old_locale);
+  EXPECT_EQ("\375\067s", value);
+}
+
+TEST(StringPrintfTest, DontOverwriteErrno) {
+  // Check that errno isn't overwritten unless we're printing
+  // something significantly larger than what people are normally
+  // printing in their badly written PLOG() statements.
+  errno = ECHILD;
+  string value = StringPrintf("Hello, %s!", "World");
+  EXPECT_EQ(ECHILD, errno);
+}
+
+TEST(StringPrintfTest, LargeBuf) {
+  // Check that the large buffer is handled correctly.
+  int n = 2048;
+  char* buf = new char[n+1];
+  memset(buf, ' ', n);
+  buf[n] = 0;
+  string value = StringPrintf("%s", buf);
+  EXPECT_EQ(buf, value);
+  delete[] buf;
+}
+
+}  // anonymous namespace
+}  // namespace protobuf
+}  // namespace google
diff --git a/src/google/protobuf/stubs/strutil.cc b/src/google/protobuf/stubs/strutil.cc
index ee07ce75..917b3e9f 100644
--- a/src/google/protobuf/stubs/strutil.cc
+++ b/src/google/protobuf/stubs/strutil.cc
@@ -189,6 +189,44 @@ void SplitStringUsing(const string& full,
   SplitStringToIteratorUsing(full, delim, it);
 }
 
+// Split a string using a character delimiter. Append the components
+// to 'result'.  If there are consecutive delimiters, this function
+// will return corresponding empty strings. The string is split into
+// at most the specified number of pieces greedily. This means that the
+// last piece may possibly be split further. To split into as many pieces
+// as possible, specify 0 as the number of pieces.
+//
+// If "full" is the empty string, yields an empty string as the only value.
+//
+// If "pieces" is negative for some reason, it returns the whole string
+// ----------------------------------------------------------------------
+template <typename StringType, typename ITR>
+static inline
+void SplitStringToIteratorAllowEmpty(const StringType& full,
+                                     const char* delim,
+                                     int pieces,
+                                     ITR& result) {
+  string::size_type begin_index, end_index;
+  begin_index = 0;
+
+  for (int i = 0; (i < pieces-1) || (pieces == 0); i++) {
+    end_index = full.find_first_of(delim, begin_index);
+    if (end_index == string::npos) {
+      *result++ = full.substr(begin_index);
+      return;
+    }
+    *result++ = full.substr(begin_index, (end_index - begin_index));
+    begin_index = end_index + 1;
+  }
+  *result++ = full.substr(begin_index);
+}
+
+void SplitStringAllowEmpty(const string& full, const char* delim,
+                           vector<string>* result) {
+  back_insert_iterator<vector<string> > it(*result);
+  SplitStringToIteratorAllowEmpty(full, delim, 0, it);
+}
+
 // ----------------------------------------------------------------------
 // JoinStrings()
 //    This merges a vector of string components with delim inserted
diff --git a/src/google/protobuf/stubs/strutil.h b/src/google/protobuf/stubs/strutil.h
index 4a79c224..a401c63a 100644
--- a/src/google/protobuf/stubs/strutil.h
+++ b/src/google/protobuf/stubs/strutil.h
@@ -168,6 +168,18 @@ LIBPROTOBUF_EXPORT string StringReplace(const string& s, const string& oldsub,
 LIBPROTOBUF_EXPORT void SplitStringUsing(const string& full, const char* delim,
                                          vector<string>* res);
 
+// Split a string using one or more byte delimiters, presented
+// as a nul-terminated c string. Append the components to 'result'.
+// If there are consecutive delimiters, this function will return
+// corresponding empty strings.  If you want to drop the empty
+// strings, try SplitStringUsing().
+//
+// If "full" is the empty string, yields an empty string as the only value.
+// ----------------------------------------------------------------------
+LIBPROTOBUF_EXPORT void SplitStringAllowEmpty(const string& full,
+                                              const char* delim,
+                                              vector<string>* result);
+
 // ----------------------------------------------------------------------
 // JoinStrings()
 //    These methods concatenate a vector of strings into a C++ string, using
@@ -453,5 +465,3 @@ LIBPROTOBUF_EXPORT double NoLocaleStrtod(const char* text, char** endptr);
 }  // namespace google
 
 #endif  // GOOGLE_PROTOBUF_STUBS_STRUTIL_H__
-
-
diff --git a/src/google/protobuf/stubs/substitute.cc b/src/google/protobuf/stubs/substitute.cc
index b542aaa4..259245b3 100644
--- a/src/google/protobuf/stubs/substitute.cc
+++ b/src/google/protobuf/stubs/substitute.cc
@@ -32,7 +32,7 @@
 
 #include <google/protobuf/stubs/substitute.h>
 #include <google/protobuf/stubs/strutil.h>
-#include <google/protobuf/stubs/stl_util-inl.h>
+#include <google/protobuf/stubs/stl_util.h>
 
 namespace google {
 namespace protobuf {
diff --git a/src/google/protobuf/stubs/template_util.h b/src/google/protobuf/stubs/template_util.h
new file mode 100644
index 00000000..4f30ffa3
--- /dev/null
+++ b/src/google/protobuf/stubs/template_util.h
@@ -0,0 +1,138 @@
+// Copyright 2005 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: lar@google.com (Laramie Leavitt)
+//
+// Template metaprogramming utility functions.
+//
+// This code is compiled directly on many platforms, including client
+// platforms like Windows, Mac, and embedded systems.  Before making
+// any changes here, make sure that you're not breaking any platforms.
+//
+//
+// The names choosen here reflect those used in tr1 and the boost::mpl
+// library, there are similar operations used in the Loki library as
+// well.  I prefer the boost names for 2 reasons:
+// 1.  I think that portions of the Boost libraries are more likely to
+// be included in the c++ standard.
+// 2.  It is not impossible that some of the boost libraries will be
+// included in our own build in the future.
+// Both of these outcomes means that we may be able to directly replace
+// some of these with boost equivalents.
+//
+#ifndef GOOGLE_PROTOBUF_TEMPLATE_UTIL_H_
+#define GOOGLE_PROTOBUF_TEMPLATE_UTIL_H_
+
+namespace google {
+namespace protobuf {
+namespace internal {
+
+// Types small_ and big_ are guaranteed such that sizeof(small_) <
+// sizeof(big_)
+typedef char small_;
+
+struct big_ {
+  char dummy[2];
+};
+
+// Identity metafunction.
+template <class T>
+struct identity_ {
+  typedef T type;
+};
+
+// integral_constant, defined in tr1, is a wrapper for an integer
+// value. We don't really need this generality; we could get away
+// with hardcoding the integer type to bool. We use the fully
+// general integer_constant for compatibility with tr1.
+
+template<class T, T v>
+struct integral_constant {
+  static const T value = v;
+  typedef T value_type;
+  typedef integral_constant<T, v> type;
+};
+
+template <class T, T v> const T integral_constant<T, v>::value;
+
+
+// Abbreviations: true_type and false_type are structs that represent boolean
+// true and false values. Also define the boost::mpl versions of those names,
+// true_ and false_.
+typedef integral_constant<bool, true>  true_type;
+typedef integral_constant<bool, false> false_type;
+typedef true_type  true_;
+typedef false_type false_;
+
+// if_ is a templatized conditional statement.
+// if_<cond, A, B> is a compile time evaluation of cond.
+// if_<>::type contains A if cond is true, B otherwise.
+template<bool cond, typename A, typename B>
+struct if_{
+  typedef A type;
+};
+
+template<typename A, typename B>
+struct if_<false, A, B> {
+  typedef B type;
+};
+
+
+// type_equals_ is a template type comparator, similar to Loki IsSameType.
+// type_equals_<A, B>::value is true iff "A" is the same type as "B".
+//
+// New code should prefer base::is_same, defined in base/type_traits.h.
+// It is functionally identical, but is_same is the standard spelling.
+template<typename A, typename B>
+struct type_equals_ : public false_ {
+};
+
+template<typename A>
+struct type_equals_<A, A> : public true_ {
+};
+
+// and_ is a template && operator.
+// and_<A, B>::value evaluates "A::value && B::value".
+template<typename A, typename B>
+struct and_ : public integral_constant<bool, (A::value && B::value)> {
+};
+
+// or_ is a template || operator.
+// or_<A, B>::value evaluates "A::value || B::value".
+template<typename A, typename B>
+struct or_ : public integral_constant<bool, (A::value || B::value)> {
+};
+
+
+}  // namespace internal
+}  // namespace protobuf
+}  // namespace google
+
+#endif  // GOOGLE_PROTOBUF_TEMPLATE_UTIL_H_
diff --git a/src/google/protobuf/stubs/template_util_unittest.cc b/src/google/protobuf/stubs/template_util_unittest.cc
new file mode 100644
index 00000000..b1745e2b
--- /dev/null
+++ b/src/google/protobuf/stubs/template_util_unittest.cc
@@ -0,0 +1,130 @@
+// Copyright 2005 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: lar@google.com (Laramie Leavitt)
+//
+// These tests are really compile time tests.
+// If you try to step through this in a debugger
+// you will not see any evaluations, merely that
+// value is assigned true or false sequentially.
+
+#include <google/protobuf/stubs/template_util.h>
+
+#include <google/protobuf/testing/googletest.h>
+#include <gtest/gtest.h>
+
+namespace GOOGLE_NAMESPACE = google::protobuf::internal;
+
+namespace google {
+namespace protobuf {
+namespace internal {
+namespace {
+
+TEST(TemplateUtilTest, TestSize) {
+  EXPECT_GT(sizeof(GOOGLE_NAMESPACE::big_), sizeof(GOOGLE_NAMESPACE::small_));
+}
+
+TEST(TemplateUtilTest, TestIntegralConstants) {
+  // test the built-in types.
+  EXPECT_TRUE(true_type::value);
+  EXPECT_FALSE(false_type::value);
+
+  typedef integral_constant<int, 1> one_type;
+  EXPECT_EQ(1, one_type::value);
+}
+
+TEST(TemplateUtilTest, TestTemplateIf) {
+  typedef if_<true, true_type, false_type>::type if_true;
+  EXPECT_TRUE(if_true::value);
+
+  typedef if_<false, true_type, false_type>::type if_false;
+  EXPECT_FALSE(if_false::value);
+}
+
+TEST(TemplateUtilTest, TestTemplateTypeEquals) {
+  // Check that the TemplateTypeEquals works correctly.
+  bool value = false;
+
+  // Test the same type is true.
+  value = type_equals_<int, int>::value;
+  EXPECT_TRUE(value);
+
+  // Test different types are false.
+  value = type_equals_<float, int>::value;
+  EXPECT_FALSE(value);
+
+  // Test type aliasing.
+  typedef const int foo;
+  value = type_equals_<const foo, const int>::value;
+  EXPECT_TRUE(value);
+}
+
+TEST(TemplateUtilTest, TestTemplateAndOr) {
+  // Check that the TemplateTypeEquals works correctly.
+  bool value = false;
+
+  // Yes && Yes == true.
+  value = and_<true_, true_>::value;
+  EXPECT_TRUE(value);
+  // Yes && No == false.
+  value = and_<true_, false_>::value;
+  EXPECT_FALSE(value);
+  // No && Yes == false.
+  value = and_<false_, true_>::value;
+  EXPECT_FALSE(value);
+  // No && No == false.
+  value = and_<false_, false_>::value;
+  EXPECT_FALSE(value);
+
+  // Yes || Yes == true.
+  value = or_<true_, true_>::value;
+  EXPECT_TRUE(value);
+  // Yes || No == true.
+  value = or_<true_, false_>::value;
+  EXPECT_TRUE(value);
+  // No || Yes == true.
+  value = or_<false_, true_>::value;
+  EXPECT_TRUE(value);
+  // No || No == false.
+  value = or_<false_, false_>::value;
+  EXPECT_FALSE(value);
+}
+
+TEST(TemplateUtilTest, TestIdentity) {
+  EXPECT_TRUE(
+      (type_equals_<GOOGLE_NAMESPACE::identity_<int>::type, int>::value));
+  EXPECT_TRUE(
+      (type_equals_<GOOGLE_NAMESPACE::identity_<void>::type, void>::value));
+}
+
+}  // anonymous namespace
+}  // namespace internal
+}  // namespace protobuf
+}  // namespace google
diff --git a/src/google/protobuf/stubs/type_traits.h b/src/google/protobuf/stubs/type_traits.h
new file mode 100644
index 00000000..997f35d4
--- /dev/null
+++ b/src/google/protobuf/stubs/type_traits.h
@@ -0,0 +1,346 @@
+// Copyright (c) 2006, 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: Matt Austern
+//
+// This code is compiled directly on many platforms, including client
+// platforms like Windows, Mac, and embedded systems.  Before making
+// any changes here, make sure that you're not breaking any platforms.
+//
+// Define a small subset of tr1 type traits. The traits we define are:
+//   is_integral
+//   is_floating_point
+//   is_pointer
+//   is_enum
+//   is_reference
+//   is_pod
+//   has_trivial_constructor
+//   has_trivial_copy
+//   has_trivial_assign
+//   has_trivial_destructor
+//   remove_const
+//   remove_volatile
+//   remove_cv
+//   remove_reference
+//   add_reference
+//   remove_pointer
+//   is_same
+//   is_convertible
+// We can add more type traits as required.
+
+#ifndef GOOGLE_PROTOBUF_TYPE_TRAITS_H_
+#define GOOGLE_PROTOBUF_TYPE_TRAITS_H_
+
+#include <utility>                  // For pair
+
+#include <google/protobuf/stubs/template_util.h>  // For true_type and false_type
+
+namespace google {
+namespace protobuf {
+namespace internal {
+
+template <class T> struct is_integral;
+template <class T> struct is_floating_point;
+template <class T> struct is_pointer;
+// MSVC can't compile this correctly, and neither can gcc 3.3.5 (at least)
+#if !defined(_MSC_VER) && !(defined(__GNUC__) && __GNUC__ <= 3)
+// is_enum uses is_convertible, which is not available on MSVC.
+template <class T> struct is_enum;
+#endif
+template <class T> struct is_reference;
+template <class T> struct is_pod;
+template <class T> struct has_trivial_constructor;
+template <class T> struct has_trivial_copy;
+template <class T> struct has_trivial_assign;
+template <class T> struct has_trivial_destructor;
+template <class T> struct remove_const;
+template <class T> struct remove_volatile;
+template <class T> struct remove_cv;
+template <class T> struct remove_reference;
+template <class T> struct add_reference;
+template <class T> struct remove_pointer;
+template <class T, class U> struct is_same;
+#if !defined(_MSC_VER) && !(defined(__GNUC__) && __GNUC__ <= 3)
+template <class From, class To> struct is_convertible;
+#endif
+
+// is_integral is false except for the built-in integer types. A
+// cv-qualified type is integral if and only if the underlying type is.
+template <class T> struct is_integral : false_type { };
+template<> struct is_integral<bool> : true_type { };
+template<> struct is_integral<char> : true_type { };
+template<> struct is_integral<unsigned char> : true_type { };
+template<> struct is_integral<signed char> : true_type { };
+#if defined(_MSC_VER)
+// wchar_t is not by default a distinct type from unsigned short in
+// Microsoft C.
+// See http://msdn2.microsoft.com/en-us/library/dh8che7s(VS.80).aspx
+template<> struct is_integral<__wchar_t> : true_type { };
+#else
+template<> struct is_integral<wchar_t> : true_type { };
+#endif
+template<> struct is_integral<short> : true_type { };
+template<> struct is_integral<unsigned short> : true_type { };
+template<> struct is_integral<int> : true_type { };
+template<> struct is_integral<unsigned int> : true_type { };
+template<> struct is_integral<long> : true_type { };
+template<> struct is_integral<unsigned long> : true_type { };
+#ifdef HAVE_LONG_LONG
+template<> struct is_integral<long long> : true_type { };
+template<> struct is_integral<unsigned long long> : true_type { };
+#endif
+template <class T> struct is_integral<const T> : is_integral<T> { };
+template <class T> struct is_integral<volatile T> : is_integral<T> { };
+template <class T> struct is_integral<const volatile T> : is_integral<T> { };
+
+// is_floating_point is false except for the built-in floating-point types.
+// A cv-qualified type is integral if and only if the underlying type is.
+template <class T> struct is_floating_point : false_type { };
+template<> struct is_floating_point<float> : true_type { };
+template<> struct is_floating_point<double> : true_type { };
+template<> struct is_floating_point<long double> : true_type { };
+template <class T> struct is_floating_point<const T>
+    : is_floating_point<T> { };
+template <class T> struct is_floating_point<volatile T>
+    : is_floating_point<T> { };
+template <class T> struct is_floating_point<const volatile T>
+    : is_floating_point<T> { };
+
+// is_pointer is false except for pointer types. A cv-qualified type (e.g.
+// "int* const", as opposed to "int const*") is cv-qualified if and only if
+// the underlying type is.
+template <class T> struct is_pointer : false_type { };
+template <class T> struct is_pointer<T*> : true_type { };
+template <class T> struct is_pointer<const T> : is_pointer<T> { };
+template <class T> struct is_pointer<volatile T> : is_pointer<T> { };
+template <class T> struct is_pointer<const volatile T> : is_pointer<T> { };
+
+#if !defined(_MSC_VER) && !(defined(__GNUC__) && __GNUC__ <= 3)
+
+namespace internal {
+
+template <class T> struct is_class_or_union {
+  template <class U> static small_ tester(void (U::*)());
+  template <class U> static big_ tester(...);
+  static const bool value = sizeof(tester<T>(0)) == sizeof(small_);
+};
+
+// is_convertible chokes if the first argument is an array. That's why
+// we use add_reference here.
+template <bool NotUnum, class T> struct is_enum_impl
+    : is_convertible<typename add_reference<T>::type, int> { };
+
+template <class T> struct is_enum_impl<true, T> : false_type { };
+
+}  // namespace internal
+
+// Specified by TR1 [4.5.1] primary type categories.
+
+// Implementation note:
+//
+// Each type is either void, integral, floating point, array, pointer,
+// reference, member object pointer, member function pointer, enum,
+// union or class. Out of these, only integral, floating point, reference,
+// class and enum types are potentially convertible to int. Therefore,
+// if a type is not a reference, integral, floating point or class and
+// is convertible to int, it's a enum. Adding cv-qualification to a type
+// does not change whether it's an enum.
+//
+// Is-convertible-to-int check is done only if all other checks pass,
+// because it can't be used with some types (e.g. void or classes with
+// inaccessible conversion operators).
+template <class T> struct is_enum
+    : internal::is_enum_impl<
+          is_same<T, void>::value ||
+              is_integral<T>::value ||
+              is_floating_point<T>::value ||
+              is_reference<T>::value ||
+              internal::is_class_or_union<T>::value,
+          T> { };
+
+template <class T> struct is_enum<const T> : is_enum<T> { };
+template <class T> struct is_enum<volatile T> : is_enum<T> { };
+template <class T> struct is_enum<const volatile T> : is_enum<T> { };
+
+#endif
+
+// is_reference is false except for reference types.
+template<typename T> struct is_reference : false_type {};
+template<typename T> struct is_reference<T&> : true_type {};
+
+
+// We can't get is_pod right without compiler help, so fail conservatively.
+// We will assume it's false except for arithmetic types, enumerations,
+// pointers and cv-qualified versions thereof. Note that std::pair<T,U>
+// is not a POD even if T and U are PODs.
+template <class T> struct is_pod
+ : integral_constant<bool, (is_integral<T>::value ||
+                            is_floating_point<T>::value ||
+#if !defined(_MSC_VER) && !(defined(__GNUC__) && __GNUC__ <= 3)
+                            // is_enum is not available on MSVC.
+                            is_enum<T>::value ||
+#endif
+                            is_pointer<T>::value)> { };
+template <class T> struct is_pod<const T> : is_pod<T> { };
+template <class T> struct is_pod<volatile T> : is_pod<T> { };
+template <class T> struct is_pod<const volatile T> : is_pod<T> { };
+
+
+// We can't get has_trivial_constructor right without compiler help, so
+// fail conservatively. We will assume it's false except for: (1) types
+// for which is_pod is true. (2) std::pair of types with trivial
+// constructors. (3) array of a type with a trivial constructor.
+// (4) const versions thereof.
+template <class T> struct has_trivial_constructor : is_pod<T> { };
+template <class T, class U> struct has_trivial_constructor<std::pair<T, U> >
+  : integral_constant<bool,
+                      (has_trivial_constructor<T>::value &&
+                       has_trivial_constructor<U>::value)> { };
+template <class A, int N> struct has_trivial_constructor<A[N]>
+  : has_trivial_constructor<A> { };
+template <class T> struct has_trivial_constructor<const T>
+  : has_trivial_constructor<T> { };
+
+// We can't get has_trivial_copy right without compiler help, so fail
+// conservatively. We will assume it's false except for: (1) types
+// for which is_pod is true. (2) std::pair of types with trivial copy
+// constructors. (3) array of a type with a trivial copy constructor.
+// (4) const versions thereof.
+template <class T> struct has_trivial_copy : is_pod<T> { };
+template <class T, class U> struct has_trivial_copy<std::pair<T, U> >
+  : integral_constant<bool,
+                      (has_trivial_copy<T>::value &&
+                       has_trivial_copy<U>::value)> { };
+template <class A, int N> struct has_trivial_copy<A[N]>
+  : has_trivial_copy<A> { };
+template <class T> struct has_trivial_copy<const T> : has_trivial_copy<T> { };
+
+// We can't get has_trivial_assign right without compiler help, so fail
+// conservatively. We will assume it's false except for: (1) types
+// for which is_pod is true. (2) std::pair of types with trivial copy
+// constructors. (3) array of a type with a trivial assign constructor.
+template <class T> struct has_trivial_assign : is_pod<T> { };
+template <class T, class U> struct has_trivial_assign<std::pair<T, U> >
+  : integral_constant<bool,
+                      (has_trivial_assign<T>::value &&
+                       has_trivial_assign<U>::value)> { };
+template <class A, int N> struct has_trivial_assign<A[N]>
+  : has_trivial_assign<A> { };
+
+// We can't get has_trivial_destructor right without compiler help, so
+// fail conservatively. We will assume it's false except for: (1) types
+// for which is_pod is true. (2) std::pair of types with trivial
+// destructors. (3) array of a type with a trivial destructor.
+// (4) const versions thereof.
+template <class T> struct has_trivial_destructor : is_pod<T> { };
+template <class T, class U> struct has_trivial_destructor<std::pair<T, U> >
+  : integral_constant<bool,
+                      (has_trivial_destructor<T>::value &&
+                       has_trivial_destructor<U>::value)> { };
+template <class A, int N> struct has_trivial_destructor<A[N]>
+  : has_trivial_destructor<A> { };
+template <class T> struct has_trivial_destructor<const T>
+  : has_trivial_destructor<T> { };
+
+// Specified by TR1 [4.7.1]
+template<typename T> struct remove_const { typedef T type; };
+template<typename T> struct remove_const<T const> { typedef T type; };
+template<typename T> struct remove_volatile { typedef T type; };
+template<typename T> struct remove_volatile<T volatile> { typedef T type; };
+template<typename T> struct remove_cv {
+  typedef typename remove_const<typename remove_volatile<T>::type>::type type;
+};
+
+
+// Specified by TR1 [4.7.2] Reference modifications.
+template<typename T> struct remove_reference { typedef T type; };
+template<typename T> struct remove_reference<T&> { typedef T type; };
+
+template <typename T> struct add_reference { typedef T& type; };
+template <typename T> struct add_reference<T&> { typedef T& type; };
+
+// Specified by TR1 [4.7.4] Pointer modifications.
+template<typename T> struct remove_pointer { typedef T type; };
+template<typename T> struct remove_pointer<T*> { typedef T type; };
+template<typename T> struct remove_pointer<T* const> { typedef T type; };
+template<typename T> struct remove_pointer<T* volatile> { typedef T type; };
+template<typename T> struct remove_pointer<T* const volatile> {
+  typedef T type; };
+
+// Specified by TR1 [4.6] Relationships between types
+template<typename T, typename U> struct is_same : public false_type { };
+template<typename T> struct is_same<T, T> : public true_type { };
+
+// Specified by TR1 [4.6] Relationships between types
+#if !defined(_MSC_VER) && !(defined(__GNUC__) && __GNUC__ <= 3)
+namespace internal {
+
+// This class is an implementation detail for is_convertible, and you
+// don't need to know how it works to use is_convertible. For those
+// who care: we declare two different functions, one whose argument is
+// of type To and one with a variadic argument list. We give them
+// return types of different size, so we can use sizeof to trick the
+// compiler into telling us which function it would have chosen if we
+// had called it with an argument of type From.  See Alexandrescu's
+// _Modern C++ Design_ for more details on this sort of trick.
+
+template <typename From, typename To>
+struct ConvertHelper {
+  static small_ Test(To);
+  static big_ Test(...);
+  static From Create();
+};
+}  // namespace internal
+
+// Inherits from true_type if From is convertible to To, false_type otherwise.
+template <typename From, typename To>
+struct is_convertible
+    : integral_constant<bool,
+                        sizeof(internal::ConvertHelper<From, To>::Test(
+                                  internal::ConvertHelper<From, To>::Create()))
+                        == sizeof(small_)> {
+};
+#endif
+
+}  // namespace internal
+}  // namespace protobuf
+}  // namespace google
+
+// Right now these macros are no-ops, and mostly just document the fact
+// these types are PODs, for human use.  They may be made more contentful
+// later.  The typedef is just to make it legal to put a semicolon after
+// these macros.
+#define DECLARE_POD(TypeName) typedef int Dummy_Type_For_DECLARE_POD
+#define DECLARE_NESTED_POD(TypeName) DECLARE_POD(TypeName)
+#define PROPAGATE_POD_FROM_TEMPLATE_ARGUMENT(TemplateName)             \
+    typedef int Dummy_Type_For_PROPAGATE_POD_FROM_TEMPLATE_ARGUMENT
+#define ENFORCE_POD(TypeName) typedef int Dummy_Type_For_ENFORCE_POD
+
+#endif  // GOOGLE_PROTOBUF_TYPE_TRAITS_H_
diff --git a/src/google/protobuf/stubs/type_traits_unittest.cc b/src/google/protobuf/stubs/type_traits_unittest.cc
new file mode 100644
index 00000000..00e5a476
--- /dev/null
+++ b/src/google/protobuf/stubs/type_traits_unittest.cc
@@ -0,0 +1,647 @@
+// Copyright (c) 2006, 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: Matt Austern
+
+#include <google/protobuf/stubs/type_traits.h>
+
+#include <stdlib.h>   // for exit()
+#include <stdio.h>
+#include <string>
+#include <vector>
+
+#include <google/protobuf/testing/googletest.h>
+#include <gtest/gtest.h>
+
+typedef int int32;
+typedef long int64;
+
+using std::string;
+using std::vector;
+using std::pair;
+
+using google::protobuf::internal::add_reference;
+using google::protobuf::internal::has_trivial_assign;
+using google::protobuf::internal::has_trivial_constructor;
+using google::protobuf::internal::has_trivial_copy;
+using google::protobuf::internal::has_trivial_destructor;
+#if !defined(_MSC_VER) && !(defined(__GNUC__) && __GNUC__ <= 3)
+using google::protobuf::internal::is_convertible;
+using google::protobuf::internal::is_enum;
+#endif
+using google::protobuf::internal::is_floating_point;
+using google::protobuf::internal::is_integral;
+using google::protobuf::internal::is_pointer;
+using google::protobuf::internal::is_pod;
+using google::protobuf::internal::is_reference;
+using google::protobuf::internal::is_same;
+using google::protobuf::internal::remove_const;
+using google::protobuf::internal::remove_cv;
+using google::protobuf::internal::remove_pointer;
+using google::protobuf::internal::remove_reference;
+using google::protobuf::internal::remove_volatile;
+
+
+// This assertion produces errors like "error: invalid use of
+// incomplete type 'struct <unnamed>::AssertTypesEq<const int, int>'"
+// when it fails.
+template<typename T, typename U> struct AssertTypesEq;
+template<typename T> struct AssertTypesEq<T, T> {};
+#define COMPILE_ASSERT_TYPES_EQ(T, U) static_cast<void>(AssertTypesEq<T, U>())
+
+// A user-defined POD type.
+struct A {
+  int n_;
+};
+
+// A user-defined non-POD type with a trivial copy constructor.
+class B {
+ public:
+  explicit B(int n) : n_(n) { }
+ private:
+  int n_;
+};
+
+// Another user-defined non-POD type with a trivial copy constructor.
+// We will explicitly declare C to have a trivial copy constructor
+// by specializing has_trivial_copy.
+class C {
+ public:
+  explicit C(int n) : n_(n) { }
+ private:
+  int n_;
+};
+
+namespace google {
+namespace protobuf {
+namespace internal {
+template<> struct has_trivial_copy<C> : true_type { };
+}  // namespace internal
+}  // namespace protobuf
+}  // namespace google
+
+// Another user-defined non-POD type with a trivial assignment operator.
+// We will explicitly declare C to have a trivial assignment operator
+// by specializing has_trivial_assign.
+class D {
+ public:
+  explicit D(int n) : n_(n) { }
+ private:
+  int n_;
+};
+
+namespace google {
+namespace protobuf {
+namespace internal {
+template<> struct has_trivial_assign<D> : true_type { };
+}  // namespace internal
+}  // namespace protobuf
+}  // namespace google
+
+// Another user-defined non-POD type with a trivial constructor.
+// We will explicitly declare E to have a trivial constructor
+// by specializing has_trivial_constructor.
+class E {
+ public:
+  int n_;
+};
+
+namespace google {
+namespace protobuf {
+namespace internal {
+template<> struct has_trivial_constructor<E> : true_type { };
+}  // namespace internal
+}  // namespace protobuf
+}  // namespace google
+
+// Another user-defined non-POD type with a trivial destructor.
+// We will explicitly declare E to have a trivial destructor
+// by specializing has_trivial_destructor.
+class F {
+ public:
+  explicit F(int n) : n_(n) { }
+ private:
+  int n_;
+};
+
+namespace google {
+namespace protobuf {
+namespace internal {
+template<> struct has_trivial_destructor<F> : true_type { };
+}  // namespace internal
+}  // namespace protobuf
+}  // namespace google
+
+enum G {};
+
+union H {};
+
+class I {
+ public:
+  operator int() const;
+};
+
+class J {
+ private:
+  operator int() const;
+};
+
+namespace google {
+namespace protobuf {
+namespace {
+
+// A base class and a derived class that inherits from it, used for
+// testing conversion type traits.
+class Base {
+ public:
+  virtual ~Base() { }
+};
+
+class Derived : public Base {
+};
+
+TEST(TypeTraitsTest, TestIsInteger) {
+  // Verify that is_integral is true for all integer types.
+  EXPECT_TRUE(is_integral<bool>::value);
+  EXPECT_TRUE(is_integral<char>::value);
+  EXPECT_TRUE(is_integral<unsigned char>::value);
+  EXPECT_TRUE(is_integral<signed char>::value);
+  EXPECT_TRUE(is_integral<wchar_t>::value);
+  EXPECT_TRUE(is_integral<int>::value);
+  EXPECT_TRUE(is_integral<unsigned int>::value);
+  EXPECT_TRUE(is_integral<short>::value);
+  EXPECT_TRUE(is_integral<unsigned short>::value);
+  EXPECT_TRUE(is_integral<long>::value);
+  EXPECT_TRUE(is_integral<unsigned long>::value);
+
+  // Verify that is_integral is false for a few non-integer types.
+  EXPECT_FALSE(is_integral<void>::value);
+  EXPECT_FALSE(is_integral<float>::value);
+  EXPECT_FALSE(is_integral<string>::value);
+  EXPECT_FALSE(is_integral<int*>::value);
+  EXPECT_FALSE(is_integral<A>::value);
+  EXPECT_FALSE((is_integral<pair<int, int> >::value));
+
+  // Verify that cv-qualified integral types are still integral, and
+  // cv-qualified non-integral types are still non-integral.
+  EXPECT_TRUE(is_integral<const char>::value);
+  EXPECT_TRUE(is_integral<volatile bool>::value);
+  EXPECT_TRUE(is_integral<const volatile unsigned int>::value);
+  EXPECT_FALSE(is_integral<const float>::value);
+  EXPECT_FALSE(is_integral<int* volatile>::value);
+  EXPECT_FALSE(is_integral<const volatile string>::value);
+}
+
+TEST(TypeTraitsTest, TestIsFloating) {
+  // Verify that is_floating_point is true for all floating-point types.
+  EXPECT_TRUE(is_floating_point<float>::value);
+  EXPECT_TRUE(is_floating_point<double>::value);
+  EXPECT_TRUE(is_floating_point<long double>::value);
+
+  // Verify that is_floating_point is false for a few non-float types.
+  EXPECT_FALSE(is_floating_point<void>::value);
+  EXPECT_FALSE(is_floating_point<long>::value);
+  EXPECT_FALSE(is_floating_point<string>::value);
+  EXPECT_FALSE(is_floating_point<float*>::value);
+  EXPECT_FALSE(is_floating_point<A>::value);
+  EXPECT_FALSE((is_floating_point<pair<int, int> >::value));
+
+  // Verify that cv-qualified floating point types are still floating, and
+  // cv-qualified non-floating types are still non-floating.
+  EXPECT_TRUE(is_floating_point<const float>::value);
+  EXPECT_TRUE(is_floating_point<volatile double>::value);
+  EXPECT_TRUE(is_floating_point<const volatile long double>::value);
+  EXPECT_FALSE(is_floating_point<const int>::value);
+  EXPECT_FALSE(is_floating_point<volatile string>::value);
+  EXPECT_FALSE(is_floating_point<const volatile char>::value);
+}
+
+TEST(TypeTraitsTest, TestIsPointer) {
+  // Verify that is_pointer is true for some pointer types.
+  EXPECT_TRUE(is_pointer<int*>::value);
+  EXPECT_TRUE(is_pointer<void*>::value);
+  EXPECT_TRUE(is_pointer<string*>::value);
+  EXPECT_TRUE(is_pointer<const void*>::value);
+  EXPECT_TRUE(is_pointer<volatile float* const*>::value);
+
+  // Verify that is_pointer is false for some non-pointer types.
+  EXPECT_FALSE(is_pointer<void>::value);
+  EXPECT_FALSE(is_pointer<float&>::value);
+  EXPECT_FALSE(is_pointer<long>::value);
+  EXPECT_FALSE(is_pointer<vector<int*> >::value);
+  EXPECT_FALSE(is_pointer<int[5]>::value);
+
+  // A function pointer is a pointer, but a function type, or a function
+  // reference type, is not.
+  EXPECT_TRUE(is_pointer<int (*)(int x)>::value);
+  EXPECT_FALSE(is_pointer<void(char x)>::value);
+  EXPECT_FALSE(is_pointer<double (&)(string x)>::value);
+
+  // Verify that is_pointer<T> is true for some cv-qualified pointer types,
+  // and false for some cv-qualified non-pointer types.
+  EXPECT_TRUE(is_pointer<int* const>::value);
+  EXPECT_TRUE(is_pointer<const void* volatile>::value);
+  EXPECT_TRUE(is_pointer<char** const volatile>::value);
+  EXPECT_FALSE(is_pointer<const int>::value);
+  EXPECT_FALSE(is_pointer<volatile vector<int*> >::value);
+  EXPECT_FALSE(is_pointer<const volatile double>::value);
+}
+
+TEST(TypeTraitsTest, TestIsEnum) {
+// is_enum isn't supported on MSVC or gcc 3.x
+#if !defined(_MSC_VER) && !(defined(__GNUC__) && __GNUC__ <= 3)
+  // Verify that is_enum is true for enum types.
+  EXPECT_TRUE(is_enum<G>::value);
+  EXPECT_TRUE(is_enum<const G>::value);
+  EXPECT_TRUE(is_enum<volatile G>::value);
+  EXPECT_TRUE(is_enum<const volatile G>::value);
+
+  // Verify that is_enum is false for a few non-enum types.
+  EXPECT_FALSE(is_enum<void>::value);
+  EXPECT_FALSE(is_enum<G&>::value);
+  EXPECT_FALSE(is_enum<G[1]>::value);
+  EXPECT_FALSE(is_enum<const G[1]>::value);
+  EXPECT_FALSE(is_enum<G[]>::value);
+  EXPECT_FALSE(is_enum<int>::value);
+  EXPECT_FALSE(is_enum<float>::value);
+  EXPECT_FALSE(is_enum<A>::value);
+  EXPECT_FALSE(is_enum<A*>::value);
+  EXPECT_FALSE(is_enum<const A>::value);
+  EXPECT_FALSE(is_enum<H>::value);
+  EXPECT_FALSE(is_enum<I>::value);
+  EXPECT_FALSE(is_enum<J>::value);
+  EXPECT_FALSE(is_enum<void()>::value);
+  EXPECT_FALSE(is_enum<void(*)()>::value);
+  EXPECT_FALSE(is_enum<int A::*>::value);
+  EXPECT_FALSE(is_enum<void (A::*)()>::value);
+#endif
+}
+
+TEST(TypeTraitsTest, TestIsReference) {
+  // Verifies that is_reference is true for all reference types.
+  typedef float& RefFloat;
+  EXPECT_TRUE(is_reference<float&>::value);
+  EXPECT_TRUE(is_reference<const int&>::value);
+  EXPECT_TRUE(is_reference<const int*&>::value);
+  EXPECT_TRUE(is_reference<int (&)(bool)>::value);
+  EXPECT_TRUE(is_reference<RefFloat>::value);
+  EXPECT_TRUE(is_reference<const RefFloat>::value);
+  EXPECT_TRUE(is_reference<volatile RefFloat>::value);
+  EXPECT_TRUE(is_reference<const volatile RefFloat>::value);
+
+
+  // Verifies that is_reference is false for all non-reference types.
+  EXPECT_FALSE(is_reference<float>::value);
+  EXPECT_FALSE(is_reference<const float>::value);
+  EXPECT_FALSE(is_reference<volatile float>::value);
+  EXPECT_FALSE(is_reference<const volatile float>::value);
+  EXPECT_FALSE(is_reference<const int*>::value);
+  EXPECT_FALSE(is_reference<int()>::value);
+  EXPECT_FALSE(is_reference<void(*)(const char&)>::value);
+}
+
+TEST(TypeTraitsTest, TestAddReference) {
+  COMPILE_ASSERT_TYPES_EQ(int&, add_reference<int>::type);
+  COMPILE_ASSERT_TYPES_EQ(const int&, add_reference<const int>::type);
+  COMPILE_ASSERT_TYPES_EQ(volatile int&,
+                          add_reference<volatile int>::type);
+  COMPILE_ASSERT_TYPES_EQ(const volatile int&,
+                          add_reference<const volatile int>::type);
+  COMPILE_ASSERT_TYPES_EQ(int&, add_reference<int&>::type);
+  COMPILE_ASSERT_TYPES_EQ(const int&, add_reference<const int&>::type);
+  COMPILE_ASSERT_TYPES_EQ(volatile int&,
+                          add_reference<volatile int&>::type);
+  COMPILE_ASSERT_TYPES_EQ(const volatile int&,
+                          add_reference<const volatile int&>::type);
+}
+
+TEST(TypeTraitsTest, TestIsPod) {
+  // Verify that arithmetic types and pointers are marked as PODs.
+  EXPECT_TRUE(is_pod<bool>::value);
+  EXPECT_TRUE(is_pod<char>::value);
+  EXPECT_TRUE(is_pod<unsigned char>::value);
+  EXPECT_TRUE(is_pod<signed char>::value);
+  EXPECT_TRUE(is_pod<wchar_t>::value);
+  EXPECT_TRUE(is_pod<int>::value);
+  EXPECT_TRUE(is_pod<unsigned int>::value);
+  EXPECT_TRUE(is_pod<short>::value);
+  EXPECT_TRUE(is_pod<unsigned short>::value);
+  EXPECT_TRUE(is_pod<long>::value);
+  EXPECT_TRUE(is_pod<unsigned long>::value);
+  EXPECT_TRUE(is_pod<float>::value);
+  EXPECT_TRUE(is_pod<double>::value);
+  EXPECT_TRUE(is_pod<long double>::value);
+  EXPECT_TRUE(is_pod<string*>::value);
+  EXPECT_TRUE(is_pod<A*>::value);
+  EXPECT_TRUE(is_pod<const B*>::value);
+  EXPECT_TRUE(is_pod<C**>::value);
+  EXPECT_TRUE(is_pod<const int>::value);
+  EXPECT_TRUE(is_pod<char* volatile>::value);
+  EXPECT_TRUE(is_pod<const volatile double>::value);
+#if !defined(_MSC_VER) && !(defined(__GNUC__) && __GNUC__ <= 3)
+  EXPECT_TRUE(is_pod<G>::value);
+  EXPECT_TRUE(is_pod<const G>::value);
+  EXPECT_TRUE(is_pod<volatile G>::value);
+  EXPECT_TRUE(is_pod<const volatile G>::value);
+#endif
+
+  // Verify that some non-POD types are not marked as PODs.
+  EXPECT_FALSE(is_pod<void>::value);
+  EXPECT_FALSE(is_pod<string>::value);
+  EXPECT_FALSE((is_pod<pair<int, int> >::value));
+  EXPECT_FALSE(is_pod<A>::value);
+  EXPECT_FALSE(is_pod<B>::value);
+  EXPECT_FALSE(is_pod<C>::value);
+  EXPECT_FALSE(is_pod<const string>::value);
+  EXPECT_FALSE(is_pod<volatile A>::value);
+  EXPECT_FALSE(is_pod<const volatile B>::value);
+}
+
+TEST(TypeTraitsTest, TestHasTrivialConstructor) {
+  // Verify that arithmetic types and pointers have trivial constructors.
+  EXPECT_TRUE(has_trivial_constructor<bool>::value);
+  EXPECT_TRUE(has_trivial_constructor<char>::value);
+  EXPECT_TRUE(has_trivial_constructor<unsigned char>::value);
+  EXPECT_TRUE(has_trivial_constructor<signed char>::value);
+  EXPECT_TRUE(has_trivial_constructor<wchar_t>::value);
+  EXPECT_TRUE(has_trivial_constructor<int>::value);
+  EXPECT_TRUE(has_trivial_constructor<unsigned int>::value);
+  EXPECT_TRUE(has_trivial_constructor<short>::value);
+  EXPECT_TRUE(has_trivial_constructor<unsigned short>::value);
+  EXPECT_TRUE(has_trivial_constructor<long>::value);
+  EXPECT_TRUE(has_trivial_constructor<unsigned long>::value);
+  EXPECT_TRUE(has_trivial_constructor<float>::value);
+  EXPECT_TRUE(has_trivial_constructor<double>::value);
+  EXPECT_TRUE(has_trivial_constructor<long double>::value);
+  EXPECT_TRUE(has_trivial_constructor<string*>::value);
+  EXPECT_TRUE(has_trivial_constructor<A*>::value);
+  EXPECT_TRUE(has_trivial_constructor<const B*>::value);
+  EXPECT_TRUE(has_trivial_constructor<C**>::value);
+
+  // Verify that pairs and arrays of such types have trivial
+  // constructors.
+  typedef int int10[10];
+  EXPECT_TRUE((has_trivial_constructor<pair<int, char*> >::value));
+  EXPECT_TRUE(has_trivial_constructor<int10>::value);
+
+  // Verify that pairs of types without trivial constructors
+  // are not marked as trivial.
+  EXPECT_FALSE((has_trivial_constructor<pair<int, string> >::value));
+  EXPECT_FALSE((has_trivial_constructor<pair<string, int> >::value));
+
+  // Verify that types without trivial constructors are
+  // correctly marked as such.
+  EXPECT_FALSE(has_trivial_constructor<string>::value);
+  EXPECT_FALSE(has_trivial_constructor<vector<int> >::value);
+
+  // Verify that E, which we have declared to have a trivial
+  // constructor, is correctly marked as such.
+  EXPECT_TRUE(has_trivial_constructor<E>::value);
+}
+
+TEST(TypeTraitsTest, TestHasTrivialCopy) {
+  // Verify that arithmetic types and pointers have trivial copy
+  // constructors.
+  EXPECT_TRUE(has_trivial_copy<bool>::value);
+  EXPECT_TRUE(has_trivial_copy<char>::value);
+  EXPECT_TRUE(has_trivial_copy<unsigned char>::value);
+  EXPECT_TRUE(has_trivial_copy<signed char>::value);
+  EXPECT_TRUE(has_trivial_copy<wchar_t>::value);
+  EXPECT_TRUE(has_trivial_copy<int>::value);
+  EXPECT_TRUE(has_trivial_copy<unsigned int>::value);
+  EXPECT_TRUE(has_trivial_copy<short>::value);
+  EXPECT_TRUE(has_trivial_copy<unsigned short>::value);
+  EXPECT_TRUE(has_trivial_copy<long>::value);
+  EXPECT_TRUE(has_trivial_copy<unsigned long>::value);
+  EXPECT_TRUE(has_trivial_copy<float>::value);
+  EXPECT_TRUE(has_trivial_copy<double>::value);
+  EXPECT_TRUE(has_trivial_copy<long double>::value);
+  EXPECT_TRUE(has_trivial_copy<string*>::value);
+  EXPECT_TRUE(has_trivial_copy<A*>::value);
+  EXPECT_TRUE(has_trivial_copy<const B*>::value);
+  EXPECT_TRUE(has_trivial_copy<C**>::value);
+
+  // Verify that pairs and arrays of such types have trivial
+  // copy constructors.
+  typedef int int10[10];
+  EXPECT_TRUE((has_trivial_copy<pair<int, char*> >::value));
+  EXPECT_TRUE(has_trivial_copy<int10>::value);
+
+  // Verify that pairs of types without trivial copy constructors
+  // are not marked as trivial.
+  EXPECT_FALSE((has_trivial_copy<pair<int, string> >::value));
+  EXPECT_FALSE((has_trivial_copy<pair<string, int> >::value));
+
+  // Verify that types without trivial copy constructors are
+  // correctly marked as such.
+  EXPECT_FALSE(has_trivial_copy<string>::value);
+  EXPECT_FALSE(has_trivial_copy<vector<int> >::value);
+
+  // Verify that C, which we have declared to have a trivial
+  // copy constructor, is correctly marked as such.
+  EXPECT_TRUE(has_trivial_copy<C>::value);
+}
+
+TEST(TypeTraitsTest, TestHasTrivialAssign) {
+  // Verify that arithmetic types and pointers have trivial assignment
+  // operators.
+  EXPECT_TRUE(has_trivial_assign<bool>::value);
+  EXPECT_TRUE(has_trivial_assign<char>::value);
+  EXPECT_TRUE(has_trivial_assign<unsigned char>::value);
+  EXPECT_TRUE(has_trivial_assign<signed char>::value);
+  EXPECT_TRUE(has_trivial_assign<wchar_t>::value);
+  EXPECT_TRUE(has_trivial_assign<int>::value);
+  EXPECT_TRUE(has_trivial_assign<unsigned int>::value);
+  EXPECT_TRUE(has_trivial_assign<short>::value);
+  EXPECT_TRUE(has_trivial_assign<unsigned short>::value);
+  EXPECT_TRUE(has_trivial_assign<long>::value);
+  EXPECT_TRUE(has_trivial_assign<unsigned long>::value);
+  EXPECT_TRUE(has_trivial_assign<float>::value);
+  EXPECT_TRUE(has_trivial_assign<double>::value);
+  EXPECT_TRUE(has_trivial_assign<long double>::value);
+  EXPECT_TRUE(has_trivial_assign<string*>::value);
+  EXPECT_TRUE(has_trivial_assign<A*>::value);
+  EXPECT_TRUE(has_trivial_assign<const B*>::value);
+  EXPECT_TRUE(has_trivial_assign<C**>::value);
+
+  // Verify that pairs and arrays of such types have trivial
+  // assignment operators.
+  typedef int int10[10];
+  EXPECT_TRUE((has_trivial_assign<pair<int, char*> >::value));
+  EXPECT_TRUE(has_trivial_assign<int10>::value);
+
+  // Verify that pairs of types without trivial assignment operators
+  // are not marked as trivial.
+  EXPECT_FALSE((has_trivial_assign<pair<int, string> >::value));
+  EXPECT_FALSE((has_trivial_assign<pair<string, int> >::value));
+
+  // Verify that types without trivial assignment operators are
+  // correctly marked as such.
+  EXPECT_FALSE(has_trivial_assign<string>::value);
+  EXPECT_FALSE(has_trivial_assign<vector<int> >::value);
+
+  // Verify that D, which we have declared to have a trivial
+  // assignment operator, is correctly marked as such.
+  EXPECT_TRUE(has_trivial_assign<D>::value);
+}
+
+TEST(TypeTraitsTest, TestHasTrivialDestructor) {
+  // Verify that arithmetic types and pointers have trivial destructors.
+  EXPECT_TRUE(has_trivial_destructor<bool>::value);
+  EXPECT_TRUE(has_trivial_destructor<char>::value);
+  EXPECT_TRUE(has_trivial_destructor<unsigned char>::value);
+  EXPECT_TRUE(has_trivial_destructor<signed char>::value);
+  EXPECT_TRUE(has_trivial_destructor<wchar_t>::value);
+  EXPECT_TRUE(has_trivial_destructor<int>::value);
+  EXPECT_TRUE(has_trivial_destructor<unsigned int>::value);
+  EXPECT_TRUE(has_trivial_destructor<short>::value);
+  EXPECT_TRUE(has_trivial_destructor<unsigned short>::value);
+  EXPECT_TRUE(has_trivial_destructor<long>::value);
+  EXPECT_TRUE(has_trivial_destructor<unsigned long>::value);
+  EXPECT_TRUE(has_trivial_destructor<float>::value);
+  EXPECT_TRUE(has_trivial_destructor<double>::value);
+  EXPECT_TRUE(has_trivial_destructor<long double>::value);
+  EXPECT_TRUE(has_trivial_destructor<string*>::value);
+  EXPECT_TRUE(has_trivial_destructor<A*>::value);
+  EXPECT_TRUE(has_trivial_destructor<const B*>::value);
+  EXPECT_TRUE(has_trivial_destructor<C**>::value);
+
+  // Verify that pairs and arrays of such types have trivial
+  // destructors.
+  typedef int int10[10];
+  EXPECT_TRUE((has_trivial_destructor<pair<int, char*> >::value));
+  EXPECT_TRUE(has_trivial_destructor<int10>::value);
+
+  // Verify that pairs of types without trivial destructors
+  // are not marked as trivial.
+  EXPECT_FALSE((has_trivial_destructor<pair<int, string> >::value));
+  EXPECT_FALSE((has_trivial_destructor<pair<string, int> >::value));
+
+  // Verify that types without trivial destructors are
+  // correctly marked as such.
+  EXPECT_FALSE(has_trivial_destructor<string>::value);
+  EXPECT_FALSE(has_trivial_destructor<vector<int> >::value);
+
+  // Verify that F, which we have declared to have a trivial
+  // destructor, is correctly marked as such.
+  EXPECT_TRUE(has_trivial_destructor<F>::value);
+}
+
+// Tests remove_pointer.
+TEST(TypeTraitsTest, TestRemovePointer) {
+  COMPILE_ASSERT_TYPES_EQ(int, remove_pointer<int>::type);
+  COMPILE_ASSERT_TYPES_EQ(int, remove_pointer<int*>::type);
+  COMPILE_ASSERT_TYPES_EQ(const int, remove_pointer<const int*>::type);
+  COMPILE_ASSERT_TYPES_EQ(int, remove_pointer<int* const>::type);
+  COMPILE_ASSERT_TYPES_EQ(int, remove_pointer<int* volatile>::type);
+}
+
+TEST(TypeTraitsTest, TestRemoveConst) {
+  COMPILE_ASSERT_TYPES_EQ(int, remove_const<int>::type);
+  COMPILE_ASSERT_TYPES_EQ(int, remove_const<const int>::type);
+  COMPILE_ASSERT_TYPES_EQ(int *, remove_const<int * const>::type);
+  // TR1 examples.
+  COMPILE_ASSERT_TYPES_EQ(const int *, remove_const<const int *>::type);
+  COMPILE_ASSERT_TYPES_EQ(volatile int,
+                          remove_const<const volatile int>::type);
+}
+
+TEST(TypeTraitsTest, TestRemoveVolatile) {
+  COMPILE_ASSERT_TYPES_EQ(int, remove_volatile<int>::type);
+  COMPILE_ASSERT_TYPES_EQ(int, remove_volatile<volatile int>::type);
+  COMPILE_ASSERT_TYPES_EQ(int *, remove_volatile<int * volatile>::type);
+  // TR1 examples.
+  COMPILE_ASSERT_TYPES_EQ(volatile int *,
+                          remove_volatile<volatile int *>::type);
+  COMPILE_ASSERT_TYPES_EQ(const int,
+                          remove_volatile<const volatile int>::type);
+}
+
+TEST(TypeTraitsTest, TestRemoveCV) {
+  COMPILE_ASSERT_TYPES_EQ(int, remove_cv<int>::type);
+  COMPILE_ASSERT_TYPES_EQ(int, remove_cv<volatile int>::type);
+  COMPILE_ASSERT_TYPES_EQ(int, remove_cv<const int>::type);
+  COMPILE_ASSERT_TYPES_EQ(int *, remove_cv<int * const volatile>::type);
+  // TR1 examples.
+  COMPILE_ASSERT_TYPES_EQ(const volatile int *,
+                          remove_cv<const volatile int *>::type);
+  COMPILE_ASSERT_TYPES_EQ(int,
+                          remove_cv<const volatile int>::type);
+}
+
+TEST(TypeTraitsTest, TestRemoveReference) {
+  COMPILE_ASSERT_TYPES_EQ(int, remove_reference<int>::type);
+  COMPILE_ASSERT_TYPES_EQ(int, remove_reference<int&>::type);
+  COMPILE_ASSERT_TYPES_EQ(const int, remove_reference<const int&>::type);
+  COMPILE_ASSERT_TYPES_EQ(int*, remove_reference<int * &>::type);
+}
+
+TEST(TypeTraitsTest, TestIsSame) {
+  EXPECT_TRUE((is_same<int32, int32>::value));
+  EXPECT_FALSE((is_same<int32, int64>::value));
+  EXPECT_FALSE((is_same<int64, int32>::value));
+  EXPECT_FALSE((is_same<int, const int>::value));
+
+  EXPECT_TRUE((is_same<void, void>::value));
+  EXPECT_FALSE((is_same<void, int>::value));
+  EXPECT_FALSE((is_same<int, void>::value));
+
+  EXPECT_TRUE((is_same<int*, int*>::value));
+  EXPECT_TRUE((is_same<void*, void*>::value));
+  EXPECT_FALSE((is_same<int*, void*>::value));
+  EXPECT_FALSE((is_same<void*, int*>::value));
+  EXPECT_FALSE((is_same<void*, const void*>::value));
+  EXPECT_FALSE((is_same<void*, void* const>::value));
+
+  EXPECT_TRUE((is_same<Base*, Base*>::value));
+  EXPECT_TRUE((is_same<Derived*, Derived*>::value));
+  EXPECT_FALSE((is_same<Base*, Derived*>::value));
+  EXPECT_FALSE((is_same<Derived*, Base*>::value));
+}
+
+TEST(TypeTraitsTest, TestConvertible) {
+#if !defined(_MSC_VER) && !(defined(__GNUC__) && __GNUC__ <= 3)
+  EXPECT_TRUE((is_convertible<int, int>::value));
+  EXPECT_TRUE((is_convertible<int, long>::value));
+  EXPECT_TRUE((is_convertible<long, int>::value));
+
+  EXPECT_TRUE((is_convertible<int*, void*>::value));
+  EXPECT_FALSE((is_convertible<void*, int*>::value));
+
+  EXPECT_TRUE((is_convertible<Derived*, Base*>::value));
+  EXPECT_FALSE((is_convertible<Base*, Derived*>::value));
+  EXPECT_TRUE((is_convertible<Derived*, const Base*>::value));
+  EXPECT_FALSE((is_convertible<const Derived*, Base*>::value));
+#endif
+}
+
+}  // anonymous namespace
+}  // namespace protobuf
+}  // namespace google