diff --git a/clang/test/SemaCXX/nested-name-spec.cpp b/clang/test/SemaCXX/nested-name-spec.cpp
index fef7093..8ba02fe 100644
--- a/clang/test/SemaCXX/nested-name-spec.cpp
+++ b/clang/test/SemaCXX/nested-name-spec.cpp
@@ -266,3 +266,22 @@
 
 namespace alias = A;
 double *dp = (alias::C*)0; // expected-error{{cannot initialize a variable of type 'double *' with an rvalue of type 'alias::C *'}}
+
+// http://llvm.org/PR10109
+namespace PR10109 {
+template<typename T>
+struct A {
+protected:
+  struct B;
+  struct B::C; // expected-error {{requires a template parameter list}} \
+               // expected-error {{no struct named 'C'}}
+};
+
+template<typename T>
+struct A2 {
+protected:
+  struct B;
+};
+template <typename T>
+struct A2<T>::B::C; // expected-error {{no struct named 'C'}}
+}