Access thread instance in posix platform using NoBarrier_Load and NoBarrier_Store.

src/platform-posix.cc

Index: src/platform-posix.cc
diff --git a/src/platform-posix.cc b/src/platform-posix.cc
index 94aabe8d581101fc08ffb95298de55cf3625c89d..42749e75e9e2e1d433a0c7530e4867fd0b124e1e 100644
--- a/src/platform-posix.cc
+++ b/src/platform-posix.cc
@@ -615,9 +615,12 @@ static void* ThreadEntry(void* arg) {
   // This is also initialized by the first argument to pthread_create() but we
   // don't know which thread will run first (the original thread or the new
   // one) so we initialize it here too.
-  thread->data()->thread_ = pthread_self();
+  NoBarrier_Store(reinterpret_cast<AtomicWord*>(&thread->data()->thread_),
+                  pthread_self());
   SetThreadName(thread->name());
-  ASSERT(thread->data()->thread_ != kNoThread);
+  ASSERT(static_cast<pthread_t>(
+      NoBarrier_Load(reinterpret_cast<AtomicWord*>(
+          &thread->data()->thread_))) != kNoThread);
   thread->NotifyStartedAndRun();
   return NULL;
 }
@@ -646,7 +649,9 @@ void Thread::Start() {
   ASSERT_EQ(0, result);
   result = pthread_attr_destroy(&attr);
   ASSERT_EQ(0, result);
-  ASSERT(data_->thread_ != kNoThread);
+  ASSERT(static_cast<pthread_t>(
+      NoBarrier_Load(reinterpret_cast<AtomicWord*>(
+          &data_->thread_))) != kNoThread);
   USE(result);
 }