Fixes unused function warning on Mac, and fixes compatibility with newer GCC.

test/gtest-death-test_test.cc

@@ -465,6 +465,8 @@ TEST_F(TestForDeathTest, MixedStyles) {
   EXPECT_DEATH(_exit(1), "");
 }
 
+# if GTEST_HAS_CLONE && GTEST_HAS_PTHREAD
+
 namespace {
 
 bool pthread_flag;
@@ -475,8 +477,6 @@ void SetPthreadFlag() {
 
 }  // namespace
 
-# if GTEST_HAS_CLONE && GTEST_HAS_PTHREAD
-
 TEST_F(TestForDeathTest, DoesNotExecuteAtforkHooks) {
   if (!testing::GTEST_FLAG(death_test_use_fork)) {
     testing::GTEST_FLAG(death_test_style) = "threadsafe";