Fix template instantiation for __builtin_offfsetof expressions that refer to members of anonymous structs/unions

llvm-svn: 102551
diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h
index 17f6553..4e32897 100644
--- a/clang/lib/Sema/TreeTransform.h
+++ b/clang/lib/Sema/TreeTransform.h
@@ -4219,6 +4219,9 @@
     case Node::Identifier:
       Comp.isBrackets = false;
       Comp.U.IdentInfo = ON.getFieldName();
+      if (!Comp.U.IdentInfo)
+        continue;
+        
       break;
     }
     
diff --git a/clang/test/SemaTemplate/instantiate-expr-5.cpp b/clang/test/SemaTemplate/instantiate-expr-5.cpp
index 916c4f9..6cdedda 100644
--- a/clang/test/SemaTemplate/instantiate-expr-5.cpp
+++ b/clang/test/SemaTemplate/instantiate-expr-5.cpp
@@ -19,4 +19,20 @@
   struct B { ArrayOfHasM a; };
   A<B> x;
   A<HasM> x2; // expected-note{{in instantiation of}}
+
+  template<typename T>
+  struct AnonymousUnion {
+    union {
+      int i;
+      float f;
+    };
+  };
+
+  template<typename T>
+  void test_anon_union() {
+    int array1[__builtin_offsetof(AnonymousUnion<T>, f) == 0? 1 : -1];
+    int array2[__builtin_offsetof(AnonymousUnion<int>, f) == 0? 1 : -1];
+  }
+
+  template void test_anon_union<int>();
 }