diff --git a/include/gtest/gtest.h b/include/gtest/gtest.h
index ebd3123b..dfa338b2 100644
--- a/include/gtest/gtest.h
+++ b/include/gtest/gtest.h
@@ -1242,6 +1242,52 @@ AssertionResult DoubleLE(const char* expr1, const char* expr2,
   ::testing::internal::ScopedTrace GTEST_CONCAT_TOKEN_(gtest_trace_, __LINE__)(\
     __FILE__, __LINE__, ::testing::Message() << (message))
 
+namespace internal {
+
+// This template is declared, but intentionally undefined.
+template <typename T1, typename T2>
+struct StaticAssertTypeEqHelper;
+
+template <typename T>
+struct StaticAssertTypeEqHelper<T, T> {};
+
+}  // namespace internal
+
+// Compile-time assertion for type equality.
+// StaticAssertTypeEq<type1, type2>() compiles iff type1 and type2 are
+// the same type.  The value it returns is not interesting.
+//
+// Instead of making StaticAssertTypeEq a class template, we make it a
+// function template that invokes a helper class template.  This
+// prevents a user from misusing StaticAssertTypeEq<T1, T2> by
+// defining objects of that type.
+//
+// CAVEAT:
+//
+// When used inside a method of a class template,
+// StaticAssertTypeEq<T1, T2>() is effective ONLY IF the method is
+// instantiated.  For example, given:
+//
+//   template <typename T> class Foo {
+//    public:
+//     void Bar() { testing::StaticAssertTypeEq<int, T>(); }
+//   };
+//
+// the code:
+//
+//   void Test1() { Foo<bool> foo; }
+//
+// will NOT generate a compiler error, as Foo<bool>::Bar() is never
+// actually instantiated.  Instead, you need:
+//
+//   void Test2() { Foo<bool> foo; foo.Bar(); }
+//
+// to cause a compiler error.
+template <typename T1, typename T2>
+bool StaticAssertTypeEq() {
+  internal::StaticAssertTypeEqHelper<T1, T2>();
+  return true;
+}
 
 // Defines a test.
 //
diff --git a/include/gtest/internal/gtest-death-test-internal.h b/include/gtest/internal/gtest-death-test-internal.h
index 0769fcaa..3b90c495 100644
--- a/include/gtest/internal/gtest-death-test-internal.h
+++ b/include/gtest/internal/gtest-death-test-internal.h
@@ -46,6 +46,7 @@ GTEST_DECLARE_string_(internal_run_death_test);
 
 // Names of the flags (needed for parsing Google Test flags).
 const char kDeathTestStyleFlag[] = "death_test_style";
+const char kDeathTestUseFork[] = "death_test_use_fork";
 const char kInternalRunDeathTestFlag[] = "internal_run_death_test";
 
 #ifdef GTEST_HAS_DEATH_TEST
diff --git a/include/gtest/internal/gtest-filepath.h b/include/gtest/internal/gtest-filepath.h
index 9a0682af..07fb86ae 100644
--- a/include/gtest/internal/gtest-filepath.h
+++ b/include/gtest/internal/gtest-filepath.h
@@ -34,7 +34,7 @@
 // This header file declares classes and functions used internally by
 // Google Test.  They are subject to change without notice.
 //
-// This file is #included in testing/base/internal/gtest-internal.h
+// This file is #included in <gtest/internal/gtest-internal.h>.
 // Do not include this header file separately!
 
 #ifndef GTEST_INCLUDE_GTEST_INTERNAL_GTEST_FILEPATH_H_
diff --git a/include/gtest/internal/gtest-string.h b/include/gtest/internal/gtest-string.h
index 178f14e1..566a6b57 100644
--- a/include/gtest/internal/gtest-string.h
+++ b/include/gtest/internal/gtest-string.h
@@ -35,7 +35,7 @@
 // Google Test.  They are subject to change without notice. They should not used
 // by code external to Google Test.
 //
-// This header file is #included by testing/base/internal/gtest-internal.h.
+// This header file is #included by <gtest/internal/gtest-internal.h>.
 // It should not be #included by other files.
 
 #ifndef GTEST_INCLUDE_GTEST_INTERNAL_GTEST_STRING_H_
diff --git a/src/gtest-death-test.cc b/src/gtest-death-test.cc
index b667682f..6499842c 100644
--- a/src/gtest-death-test.cc
+++ b/src/gtest-death-test.cc
@@ -68,6 +68,17 @@ GTEST_DEFINE_string_(
     "\"fast\" (child process runs the death test immediately "
     "after forking).");
 
+GTEST_DEFINE_bool_(
+    death_test_use_fork,
+    internal::BoolFromGTestEnv("death_test_use_fork", false),
+    "Instructs to use fork()/_exit() instead of clone() in death tests. "
+    "Useful when running under valgrind or similar tools if those "
+    "do not support clone(). Valgrind 3.3.1 will just fail if "
+    "it sees an unsupported combination of clone() flags. "
+    "It is not recommended to use this flag w/o valgrind though it will "
+    "work in 99% of the cases. Once valgrind is fixed, this flag will "
+    "most likely be removed.");
+
 namespace internal {
 GTEST_DEFINE_string_(
     internal_run_death_test, "",
@@ -603,8 +614,18 @@ static pid_t ExecDeathTestFork(char* const* argv, int close_fd) {
   void* const stack_top =
       static_cast<char*>(stack) + (stack_grows_down ? stack_size : 0);
   ExecDeathTestArgs args = { argv, close_fd };
-  const pid_t child_pid = clone(&ExecDeathTestChildMain, stack_top,
-                                SIGCHLD, &args);
+  pid_t child_pid;
+  if (GTEST_FLAG(death_test_use_fork)) {
+    // Valgrind-friendly version. As of valgrind 3.3.1 the clone() call below
+    // is not supported (valgrind will fail with an error message).
+    if ((child_pid = fork()) == 0) {
+      ExecDeathTestChildMain(&args);
+      _exit(0);
+    }
+  } else {
+    child_pid = clone(&ExecDeathTestChildMain, stack_top,
+                      SIGCHLD, &args);
+  }
   GTEST_DEATH_TEST_CHECK_(child_pid != -1);
   GTEST_DEATH_TEST_CHECK_(munmap(stack, stack_size) != -1);
   return child_pid;
diff --git a/src/gtest-internal-inl.h b/src/gtest-internal-inl.h
index b8f67c18..353c40a6 100644
--- a/src/gtest-internal-inl.h
+++ b/src/gtest-internal-inl.h
@@ -66,6 +66,7 @@ namespace testing {
 GTEST_DECLARE_bool_(break_on_failure);
 GTEST_DECLARE_bool_(catch_exceptions);
 GTEST_DECLARE_string_(color);
+GTEST_DECLARE_bool_(death_test_use_fork);
 GTEST_DECLARE_string_(filter);
 GTEST_DECLARE_bool_(list_tests);
 GTEST_DECLARE_string_(output);
@@ -100,6 +101,7 @@ class GTestFlagSaver {
     catch_exceptions_ = GTEST_FLAG(catch_exceptions);
     color_ = GTEST_FLAG(color);
     death_test_style_ = GTEST_FLAG(death_test_style);
+    death_test_use_fork_ = GTEST_FLAG(death_test_use_fork);
     filter_ = GTEST_FLAG(filter);
     internal_run_death_test_ = GTEST_FLAG(internal_run_death_test);
     list_tests_ = GTEST_FLAG(list_tests);
@@ -114,6 +116,7 @@ class GTestFlagSaver {
     GTEST_FLAG(catch_exceptions) = catch_exceptions_;
     GTEST_FLAG(color) = color_;
     GTEST_FLAG(death_test_style) = death_test_style_;
+    GTEST_FLAG(death_test_use_fork) = death_test_use_fork_;
     GTEST_FLAG(filter) = filter_;
     GTEST_FLAG(internal_run_death_test) = internal_run_death_test_;
     GTEST_FLAG(list_tests) = list_tests_;
@@ -127,6 +130,7 @@ class GTestFlagSaver {
   bool catch_exceptions_;
   String color_;
   String death_test_style_;
+  bool death_test_use_fork_;
   String filter_;
   String internal_run_death_test_;
   bool list_tests_;
diff --git a/src/gtest.cc b/src/gtest.cc
index a9ca334a..ae20d874 100644
--- a/src/gtest.cc
+++ b/src/gtest.cc
@@ -3867,6 +3867,8 @@ void ParseGoogleTestFlagsOnlyImpl(int* argc, CharType** argv) {
         ParseStringFlag(arg, kColorFlag, &GTEST_FLAG(color)) ||
         ParseStringFlag(arg, kDeathTestStyleFlag,
                         &GTEST_FLAG(death_test_style)) ||
+        ParseBoolFlag(arg, kDeathTestUseFork,
+                      &GTEST_FLAG(death_test_use_fork)) ||
         ParseStringFlag(arg, kFilterFlag, &GTEST_FLAG(filter)) ||
         ParseStringFlag(arg, kInternalRunDeathTestFlag,
                         &GTEST_FLAG(internal_run_death_test)) ||
diff --git a/test/gtest-death-test_test.cc b/test/gtest-death-test_test.cc
index 07268d00..204ec413 100644
--- a/test/gtest-death-test_test.cc
+++ b/test/gtest-death-test_test.cc
@@ -347,11 +347,13 @@ void SetPthreadFlag() {
 }  // namespace
 
 TEST_F(TestForDeathTest, DoesNotExecuteAtforkHooks) {
-  testing::GTEST_FLAG(death_test_style) = "threadsafe";
-  pthread_flag = false;
-  ASSERT_EQ(0, pthread_atfork(&SetPthreadFlag, NULL, NULL));
-  ASSERT_DEATH(_exit(1), "");
-  ASSERT_FALSE(pthread_flag);
+  if (!testing::GTEST_FLAG(death_test_use_fork)) {
+    testing::GTEST_FLAG(death_test_style) = "threadsafe";
+    pthread_flag = false;
+    ASSERT_EQ(0, pthread_atfork(&SetPthreadFlag, NULL, NULL));
+    ASSERT_DEATH(_exit(1), "");
+    ASSERT_FALSE(pthread_flag);
+  }
 }
 
 // Tests that a method of another class can be used in a death test.
@@ -561,7 +563,7 @@ TEST_F(TestForDeathTest, AssertDebugDeathAborts) {
 #endif  // _NDEBUG
 
 // Tests the *_EXIT family of macros, using a variety of predicates.
-TEST_F(TestForDeathTest, ExitMacros) {
+static void TestExitMacros() {
   EXPECT_EXIT(_exit(1),  testing::ExitedWithCode(1),  "");
   ASSERT_EXIT(_exit(42), testing::ExitedWithCode(42), "");
   EXPECT_EXIT(raise(SIGKILL), testing::KilledBySignal(SIGKILL), "") << "foo";
@@ -578,6 +580,15 @@ TEST_F(TestForDeathTest, ExitMacros) {
   }, "This failure is expected, too.");
 }
 
+TEST_F(TestForDeathTest, ExitMacros) {
+  TestExitMacros();
+}
+
+TEST_F(TestForDeathTest, ExitMacrosUsingFork) {
+  testing::GTEST_FLAG(death_test_use_fork) = true;
+  TestExitMacros();
+}
+
 TEST_F(TestForDeathTest, InvalidStyle) {
   testing::GTEST_FLAG(death_test_style) = "rococo";
   EXPECT_NONFATAL_FAILURE({  // NOLINT
diff --git a/test/gtest_env_var_test.py b/test/gtest_env_var_test.py
index 1b86b5a9..67a22493 100755
--- a/test/gtest_env_var_test.py
+++ b/test/gtest_env_var_test.py
@@ -109,6 +109,7 @@ def TestEnvVarAffectsFlag(command):
   if IS_LINUX:
     TestFlag(command, 'stack_trace_depth', '0', '100')
     TestFlag(command, 'death_test_style', 'thread-safe', 'fast')
+    TestFlag(command, 'death_test_use_fork', '1', '0')
 
 
 if IS_WINDOWS:
diff --git a/test/gtest_env_var_test_.cc b/test/gtest_env_var_test_.cc
index 16b31103..bbccd462 100644
--- a/test/gtest_env_var_test_.cc
+++ b/test/gtest_env_var_test_.cc
@@ -71,6 +71,11 @@ void PrintFlag(const char* flag) {
     return;
   }
 
+  if (strcmp(flag, "death_test_use_fork") == 0) {
+    cout << GTEST_FLAG(death_test_use_fork);
+    return;
+  }
+
   if (strcmp(flag, "filter") == 0) {
     cout << GTEST_FLAG(filter);
     return;
diff --git a/test/gtest_nc.cc b/test/gtest_nc.cc
index 5cbaeefa..73b5db6d 100644
--- a/test/gtest_nc.cc
+++ b/test/gtest_nc.cc
@@ -181,6 +181,47 @@ INSTANTIATE_TYPED_TEST_CASE_P(My, FooTest, testing::Types<int>);
 // Wrong name prefix: "My" has been used.
 INSTANTIATE_TYPED_TEST_CASE_P(My, FooTest, testing::Types<double>);
 
+#elif defined(TEST_STATIC_ASSERT_TYPE_EQ_IS_NOT_A_TYPE)
+
+#include <gtest/gtest.h>
+
+// Tests that StaticAssertTypeEq<T1, T2> cannot be used as a type.
+testing::StaticAssertTypeEq<int, int> dummy;
+
+#elif defined(TEST_STATIC_ASSERT_TYPE_EQ_WORKS_IN_NAMESPACE)
+
+#include <gtest/gtest.h>
+
+// Tests that StaticAssertTypeEq<T1, T2> works in a namespace scope.
+static bool dummy = testing::StaticAssertTypeEq<int, const int>();
+
+#elif defined(TEST_STATIC_ASSERT_TYPE_EQ_WORKS_IN_CLASS)
+
+#include <gtest/gtest.h>
+
+template <typename T>
+class Helper {
+ public:
+  // Tests that StaticAssertTypeEq<T1, T2> works in a class.
+  Helper() { testing::StaticAssertTypeEq<int, T>(); }
+
+  void DoSomething() {}
+};
+
+void Test() {
+  Helper<bool> h;
+  h.DoSomething();  // To avoid the "unused variable" warning.
+}
+
+#elif defined(TEST_STATIC_ASSERT_TYPE_EQ_WORKS_IN_FUNCTION)
+
+#include <gtest/gtest.h>
+
+void Test() {
+  // Tests that StaticAssertTypeEq<T1, T2> works inside a function.
+  testing::StaticAssertTypeEq<const int, int>();
+}
+
 #else
 // A sanity test.  This should compile.
 
diff --git a/test/gtest_nc_test.py b/test/gtest_nc_test.py
index 683bd370..6e77d708 100755
--- a/test/gtest_nc_test.py
+++ b/test/gtest_nc_test.py
@@ -78,6 +78,18 @@ class GTestNCTest(unittest.TestCase):
       ('CATCHES_INSTANTIATE_TYPED_TESET_CASE_P_WITH_SAME_NAME_PREFIX',
        [r'redefinition of.*My.*FooTest']),
 
+      ('STATIC_ASSERT_TYPE_EQ_IS_NOT_A_TYPE',
+       [r'StaticAssertTypeEq.* does not name a type']),
+
+      ('STATIC_ASSERT_TYPE_EQ_WORKS_IN_NAMESPACE',
+       [r'StaticAssertTypeEq.*int.*const int']),
+
+      ('STATIC_ASSERT_TYPE_EQ_WORKS_IN_CLASS',
+       [r'StaticAssertTypeEq.*int.*bool']),
+
+      ('STATIC_ASSERT_TYPE_EQ_WORKS_IN_FUNCTION',
+       [r'StaticAssertTypeEq.*const int.*int']),
+
       ('SANITY',
        None)
       ]
diff --git a/test/gtest_unittest.cc b/test/gtest_unittest.cc
index 1cbb27f6..2794f7ec 100644
--- a/test/gtest_unittest.cc
+++ b/test/gtest_unittest.cc
@@ -86,6 +86,7 @@ using testing::DoubleLE;
 using testing::FloatLE;
 using testing::GTEST_FLAG(break_on_failure);
 using testing::GTEST_FLAG(catch_exceptions);
+using testing::GTEST_FLAG(death_test_use_fork);
 using testing::GTEST_FLAG(color);
 using testing::GTEST_FLAG(filter);
 using testing::GTEST_FLAG(list_tests);
@@ -98,6 +99,7 @@ using testing::IsNotSubstring;
 using testing::IsSubstring;
 using testing::Message;
 using testing::ScopedFakeTestPartResultReporter;
+using testing::StaticAssertTypeEq;
 using testing::Test;
 using testing::TestPartResult;
 using testing::TestPartResultArray;
@@ -1128,6 +1130,7 @@ class GTestFlagSaverTest : public Test {
 
     GTEST_FLAG(break_on_failure) = false;
     GTEST_FLAG(catch_exceptions) = false;
+    GTEST_FLAG(death_test_use_fork) = false;
     GTEST_FLAG(color) = "auto";
     GTEST_FLAG(filter) = "";
     GTEST_FLAG(list_tests) = false;
@@ -1149,6 +1152,7 @@ class GTestFlagSaverTest : public Test {
     EXPECT_FALSE(GTEST_FLAG(break_on_failure));
     EXPECT_FALSE(GTEST_FLAG(catch_exceptions));
     EXPECT_STREQ("auto", GTEST_FLAG(color).c_str());
+    EXPECT_FALSE(GTEST_FLAG(death_test_use_fork));
     EXPECT_STREQ("", GTEST_FLAG(filter).c_str());
     EXPECT_FALSE(GTEST_FLAG(list_tests));
     EXPECT_STREQ("", GTEST_FLAG(output).c_str());
@@ -1158,6 +1162,7 @@ class GTestFlagSaverTest : public Test {
     GTEST_FLAG(break_on_failure) = true;
     GTEST_FLAG(catch_exceptions) = true;
     GTEST_FLAG(color) = "no";
+    GTEST_FLAG(death_test_use_fork) = true;
     GTEST_FLAG(filter) = "abc";
     GTEST_FLAG(list_tests) = true;
     GTEST_FLAG(output) = "xml:foo.xml";
@@ -4064,6 +4069,7 @@ struct Flags {
   // Constructs a Flags struct where each flag has its default value.
   Flags() : break_on_failure(false),
             catch_exceptions(false),
+            death_test_use_fork(false),
             filter(""),
             list_tests(false),
             output(""),
@@ -4088,6 +4094,14 @@ struct Flags {
     return flags;
   }
 
+  // Creates a Flags struct where the gtest_death_test_use_fork flag has
+  // the given value.
+  static Flags DeathTestUseFork(bool death_test_use_fork) {
+    Flags flags;
+    flags.death_test_use_fork = death_test_use_fork;
+    return flags;
+  }
+
   // Creates a Flags struct where the gtest_filter flag has the given
   // value.
   static Flags Filter(const char* filter) {
@@ -4131,6 +4145,7 @@ struct Flags {
   // These fields store the flag values.
   bool break_on_failure;
   bool catch_exceptions;
+  bool death_test_use_fork;
   const char* filter;
   bool list_tests;
   const char* output;
@@ -4145,6 +4160,7 @@ class InitGoogleTestTest : public Test {
   virtual void SetUp() {
     GTEST_FLAG(break_on_failure) = false;
     GTEST_FLAG(catch_exceptions) = false;
+    GTEST_FLAG(death_test_use_fork) = false;
     GTEST_FLAG(filter) = "";
     GTEST_FLAG(list_tests) = false;
     GTEST_FLAG(output) = "";
@@ -4167,6 +4183,7 @@ class InitGoogleTestTest : public Test {
   static void CheckFlags(const Flags& expected) {
     EXPECT_EQ(expected.break_on_failure, GTEST_FLAG(break_on_failure));
     EXPECT_EQ(expected.catch_exceptions, GTEST_FLAG(catch_exceptions));
+    EXPECT_EQ(expected.death_test_use_fork, GTEST_FLAG(death_test_use_fork));
     EXPECT_STREQ(expected.filter, GTEST_FLAG(filter).c_str());
     EXPECT_EQ(expected.list_tests, GTEST_FLAG(list_tests));
     EXPECT_STREQ(expected.output, GTEST_FLAG(output).c_str());
@@ -4373,6 +4390,22 @@ TEST_F(InitGoogleTestTest, CatchExceptions) {
   TEST_PARSING_FLAGS(argv, argv2, Flags::CatchExceptions(true));
 }
 
+// Tests parsing --gtest_death_test_use_fork.
+TEST_F(InitGoogleTestTest, DeathTestUseFork) {
+  const char* argv[] = {
+    "foo.exe",
+    "--gtest_death_test_use_fork",
+    NULL
+  };
+
+  const char* argv2[] = {
+    "foo.exe",
+    NULL
+  };
+
+  TEST_PARSING_FLAGS(argv, argv2, Flags::DeathTestUseFork(true));
+}
+
 // Tests having the same flag twice with different values.  The
 // expected behavior is that the one coming last takes precedence.
 TEST_F(InitGoogleTestTest, DuplicatedFlags) {
@@ -5000,6 +5033,32 @@ TEST(ColoredOutputTest, UsesColorsWhenTermSupportsColors) {
 #endif  // GTEST_OS_WINDOWS
 }
 
+// Verifies that StaticAssertTypeEq works in a namespace scope.
+
+static bool dummy1 = StaticAssertTypeEq<bool, bool>();
+static bool dummy2 = StaticAssertTypeEq<const int, const int>();
+
+// Verifies that StaticAssertTypeEq works in a class.
+
+template <typename T>
+class StaticAssertTypeEqTestHelper {
+ public:
+  StaticAssertTypeEqTestHelper() { StaticAssertTypeEq<bool, T>(); }
+};
+
+TEST(StaticAssertTypeEqTest, WorksInClass) {
+  StaticAssertTypeEqTestHelper<bool>();
+}
+
+// Verifies that StaticAssertTypeEq works inside a function.
+
+typedef int IntAlias;
+
+TEST(StaticAssertTypeEqTest, CompilesForEqualTypes) {
+  StaticAssertTypeEq<int, IntAlias>();
+  StaticAssertTypeEq<int*, IntAlias*>();
+}
+
 TEST(ThreadLocalTest, DefaultConstructor) {
   ThreadLocal<int> t1;
   EXPECT_EQ(0, t1.get());