__cxa_atexit does not throw.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@127977 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGDeclCXX.cpp b/lib/CodeGen/CGDeclCXX.cpp
index ed25b6d..cb1c8ed 100644
--- a/lib/CodeGen/CGDeclCXX.cpp
+++ b/lib/CodeGen/CGDeclCXX.cpp
@@ -138,6 +138,8 @@
 
   llvm::Constant *AtExitFn = CGM.CreateRuntimeFunction(AtExitFnTy,
                                                        "__cxa_atexit");
+  if (llvm::Function *Fn = dyn_cast<llvm::Function>(AtExitFn))
+    Fn->setDoesNotThrow();
 
   llvm::Constant *Handle = CGM.CreateRuntimeVariable(Int8PtrTy,
                                                      "__dso_handle");