Handle blocks in CFG that call functions marked as noreturn.

test/SemaCXX/warn-thread-safety-analysis.cpp

Index: test/SemaCXX/warn-thread-safety-analysis.cpp
diff --git a/test/SemaCXX/warn-thread-safety-analysis.cpp b/test/SemaCXX/warn-thread-safety-analysis.cpp
index 8bbaf0398fae3b9e041681d8e167ad2087ddc8c1..00ed746cd420d5a562486404e303f99fa29b7da5 100644
--- a/test/SemaCXX/warn-thread-safety-analysis.cpp
+++ b/test/SemaCXX/warn-thread-safety-analysis.cpp
@@ -2100,3 +2100,20 @@ public:
 } // end namespace SelfLockingTest
 
 
+namespace NoReturnTest {
+
+bool condition();
+void fatal() __attribute__((noreturn));
+
+Mutex mu_;
+
+void test1() {
+  MutexLock lock(&mu_);
+  if (condition()) {
+    fatal();
+    return;
+  }
+}
+
+};
+