diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 8e14fcdd6b29..36ab6ed44bdb 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -711,10 +711,13 @@ static bool IsDependentIdExpression(Sema &SemaRef, const CXXScopeSpec &SS) {
 static bool IsProvablyNotDerivedFrom(Sema &SemaRef,
                                      CXXRecordDecl *Record,
                             const llvm::SmallPtrSet<CXXRecordDecl*, 4> &Bases) {
-  Record = Record->getCanonicalDecl();
-  if (Bases.count(Record))
+  if (Bases.count(Record->getCanonicalDecl()))
     return false;
 
+  RecordDecl *RD = Record->getDefinition(SemaRef.Context);
+  if (!RD) return false;
+  Record = cast<CXXRecordDecl>(RD);
+
   for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(),
          E = Record->bases_end(); I != E; ++I) {
     CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType());
@@ -722,9 +725,6 @@ static bool IsProvablyNotDerivedFrom(Sema &SemaRef,
     if (!BaseRT) return false;
 
     CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl());
-    if (!BaseRecord->isDefinition())
-      return false;
-
     if (!IsProvablyNotDerivedFrom(SemaRef, BaseRecord, Bases))
       return false;
   }
diff --git a/clang/test/SemaCXX/member-expr.cpp b/clang/test/SemaCXX/member-expr.cpp
index cd13bcc3670e..9cd6855ccd55 100644
--- a/clang/test/SemaCXX/member-expr.cpp
+++ b/clang/test/SemaCXX/member-expr.cpp
@@ -41,3 +41,18 @@ void test2(X *xp) {
   xp->::i = 7; // expected-error{{qualified member access refers to a member in the global namespace}}
   xp->C::i = 7; // expected-error{{qualified member access refers to a member in namespace 'C'}}
 }
+
+
+namespace test3 {
+  struct NamespaceDecl;
+
+  struct NamedDecl {
+    void *getIdentifier() const;
+  };
+
+  struct NamespaceDecl : NamedDecl {
+    bool isAnonymousNamespace() const {
+      return !getIdentifier();
+    }
+  };
+}