diff --git a/lib/Sema/SemaCast.cpp b/lib/Sema/SemaCast.cpp
index 7207d04158a9854c50891d94fd340e71c7c22c05..4a7699b22e22314f0135c2e3d7f8357a51190798 100644
--- a/lib/Sema/SemaCast.cpp
+++ b/lib/Sema/SemaCast.cpp
@@ -1402,8 +1402,10 @@ TryStaticMemberPointerUpcast(Sema &Self, ExprResult &SrcExpr, QualType SrcType,
 
   // Lock down the inheritance model right now in MS ABI, whether or not the
   // pointee types are the same.
-  if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft())
+  if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
     (void)Self.isCompleteType(OpRange.getBegin(), SrcType);
+    (void)Self.isCompleteType(OpRange.getBegin(), DestType);
+  }
 
   // T == T, modulo cv
   if (!Self.Context.hasSameUnqualifiedType(SrcMemPtr->getPointeeType(),
diff --git a/test/CodeGenCXX/pr27030.cpp b/test/CodeGenCXX/pr27030.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..7a582d242ee8182eeb3982504ea8db12200a52b3
--- /dev/null
+++ b/test/CodeGenCXX/pr27030.cpp
@@ -0,0 +1,17 @@
+// RUN: %clang_cc1 -emit-llvm -triple=i386-pc-win32 %s -o - | FileCheck %s
+struct A {};
+struct B : A {};
+extern "C" {
+extern int B::*a;
+void test1() { (int A::*)(a); }
+}
+// CHECK-LABEL: define void @test1(
+// CHECK: %[[load:.*]]       = load i32, i32* @a
+// CHECK: %[[memptr_cmp:.*]] = icmp ne i32 %[[load]], -1
+// CHECK: br i1 %[[memptr_cmp]]
+
+// CHECK: %[[adj:.*]] = sub nsw i32 %[[load]], 0
+// CHECK: %[[nv_adj:.*]] = select i1 true, i32 %[[adj]], i32 0
+// CHECK: br label %memptr.converted
+
+// CHECK: %[[memptr_converted:.*]] = phi i32 [ -1, {{.*}} ], [ %[[nv_adj]], {{.*}} ]