Add test case for PR5868, and improve location information slightly for implicit "this" expressions

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@92141 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/SemaTemplate/anonymous-union.cpp b/test/SemaTemplate/anonymous-union.cpp
new file mode 100644
index 0000000..59d1f25
--- /dev/null
+++ b/test/SemaTemplate/anonymous-union.cpp
@@ -0,0 +1,19 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+// PR5868
+struct T0 {
+  int x;
+  union {
+    void *m0;
+  };
+};
+template <typename T>
+struct T1 : public T0, public T { 
+  void f0() { 
+    m0 = 0; // expected-error{{ambiguous conversion}}
+  } 
+};
+
+struct A : public T0 { };
+
+void f1(T1<A> *S) { S->f0(); } // expected-note{{instantiation of member function}}