Index: cfe/trunk/lib/CodeGen/CodeGenModule.cpp
===================================================================
--- cfe/trunk/lib/CodeGen/CodeGenModule.cpp
+++ cfe/trunk/lib/CodeGen/CodeGenModule.cpp
@@ -3000,9 +3000,13 @@
     if (F->empty()) {
       F->setCallingConv(getRuntimeCC());
 
-      if (!Local && getTriple().isOSBinFormatCOFF() &&
-          !getCodeGenOpts().LTOVisibilityPublicStd &&
-          !getTriple().isWindowsGNUEnvironment()) {
+      // In Windows Itanium environments, try to mark runtime functions
+      // dllimport. For Mingw and MSVC, don't. We don't really know if the user
+      // will link their standard library statically or dynamically. Marking
+      // functions imported when they are not imported can cause linker errors
+      // and warnings.
+      if (!Local && getTriple().isWindowsItaniumEnvironment() &&
+          !getCodeGenOpts().LTOVisibilityPublicStd) {
         const FunctionDecl *FD = GetRuntimeFunctionDecl(Context, Name);
         if (!FD || FD->hasAttr<DLLImportAttr>()) {
           F->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
Index: cfe/trunk/test/CodeGen/ms-symbol-linkage.cpp
===================================================================
--- cfe/trunk/test/CodeGen/ms-symbol-linkage.cpp
+++ cfe/trunk/test/CodeGen/ms-symbol-linkage.cpp
@@ -0,0 +1,20 @@
+// RUN: %clangxx -target aarch64-windows \
+// RUN: -fcxx-exceptions -c -o - %s \
+// RUN: | llvm-objdump -syms - 2>&1 | FileCheck %s
+
+void foo1() { throw 1; }
+// CHECK-LABEL: foo1
+// CHECK-NOT: __imp__CxxThrowException
+
+void bar();
+void foo2() noexcept(true) { bar(); }
+// CHECK-LABEL: foo2
+// CHECK-NOT: __imp___std_terminate
+
+struct A {};
+struct B { virtual void f(); };
+struct C : A, virtual B {};
+struct T {};
+T *foo3() { return dynamic_cast<T *>((C *)0); }
+// CHECK-LABEL: foo3
+// CHECK-NOT: __imp___RTDynamicCast
Index: cfe/trunk/test/CodeGenCXX/runtime-dllstorage.cpp
===================================================================
--- cfe/trunk/test/CodeGenCXX/runtime-dllstorage.cpp
+++ cfe/trunk/test/CodeGenCXX/runtime-dllstorage.cpp
@@ -108,7 +108,7 @@
 // CHECK-MS-DAG: @_Init_thread_epoch = external thread_local global i32
 // CHECK-MS-DAG: declare dso_local i32 @__tlregdtor(void ()*)
 // CHECK-MS-DAG: declare dso_local i32 @atexit(void ()*)
-// CHECK-MS-DYNAMIC-DAG: declare dllimport {{.*}} void @_CxxThrowException
+// CHECK-MS-DYNAMIC-DAG: declare {{.*}} void @_CxxThrowException
 // CHECK-MS-STATIC-DAG: declare {{.*}} void @_CxxThrowException
 // CHECK-MS-DAG: declare dso_local noalias i8* @"??2@YAPAXI@Z"
 // CHECK-MS-DAG: declare dso_local void @_Init_thread_header(i32*)
Index: cfe/trunk/test/CodeGenObjC/gnu-init.m
===================================================================
--- cfe/trunk/test/CodeGenObjC/gnu-init.m
+++ cfe/trunk/test/CodeGenObjC/gnu-init.m
@@ -100,6 +100,6 @@
 // Check our load function is in a comdat.
 // CHECK-WIN: define linkonce_odr hidden void @.objcv2_load_function() comdat {
 
-// Make sure we have dllimport on the load function
-// CHECK-WIN: declare dllimport void @__objc_load
+// Make sure we do not have dllimport on the load function
+// CHECK-WIN: declare dso_local void @__objc_load
 
Index: cfe/trunk/test/CodeGenObjCXX/msabi-stret.mm
===================================================================
--- cfe/trunk/test/CodeGenObjCXX/msabi-stret.mm
+++ cfe/trunk/test/CodeGenObjCXX/msabi-stret.mm
@@ -13,6 +13,5 @@
   return [I m:S()];
 }
 
-// CHECK: declare dllimport void @objc_msgSend_stret(i8*, i8*, ...)
+// CHECK: declare dso_local void @objc_msgSend_stret(i8*, i8*, ...)
 // CHECK-NOT: declare dllimport void @objc_msgSend(i8*, i8*, ...)
-