diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 895f930..da1fe3d 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -605,6 +605,7 @@
       MemberType = Context.getQualifiedType(MemberType, NewQuals);
 
     MarkDeclarationReferenced(Loc, *FI);
+    PerformObjectMemberConversion(Result, *FI);
     // FIXME: Might this end up being a qualified name?
     Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI,
                                       OpLoc, MemberType);
@@ -2397,7 +2398,8 @@
   if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) {
     // We may have found a field within an anonymous union or struct
     // (C++ [class.union]).
-    if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion())
+    if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion() &&
+        !BaseType->getAs<RecordType>()->getDecl()->isAnonymousStructOrUnion())
       return BuildAnonymousStructUnionMemberReference(MemberLoc, FD,
                                                       BaseExpr, OpLoc);
 
@@ -6397,6 +6399,7 @@
         Res = BuildAnonymousStructUnionMemberReference(
             OC.LocEnd, MemberDecl, Res, OC.LocEnd).takeAs<Expr>();
       } else {
+        PerformObjectMemberConversion(Res, MemberDecl);
         // MemberDecl->getType() doesn't get the right qualifiers, but it
         // doesn't matter here.
         Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd,
diff --git a/test/SemaCXX/member-expr-anonymous-union.cpp b/test/SemaCXX/member-expr-anonymous-union.cpp
new file mode 100644
index 0000000..9566df4
--- /dev/null
+++ b/test/SemaCXX/member-expr-anonymous-union.cpp
@@ -0,0 +1,9 @@
+// RUN: clang-cc %s -fsyntax-only -verify
+// PR5543
+
+struct A { int x; union { int* y; float& z; }; }; struct B : A {int a;};
+int* a(B* x) { return x->y; }
+
+struct x { union { int y; }; }; x y; template <int X> int f() { return X+y.y; }
+int g() { return f<2>(); }
+
diff --git a/test/SemaCXX/offsetof.cpp b/test/SemaCXX/offsetof.cpp
index f0290e8..e18987f 100644
--- a/test/SemaCXX/offsetof.cpp
+++ b/test/SemaCXX/offsetof.cpp
@@ -13,3 +13,6 @@
   int i = __builtin_offsetof(P, fieldThatPointsToANonPODType.m); // expected-warning{{offset of on non-POD type 'struct P'}}
 }
 
+struct Base { int x; };
+struct Derived : Base { int y; };
+int o = __builtin_offsetof(Derived, x); // expected-warning{{offset of on non-POD type}}